Patent Publication Number: US-11662673-B2

Title: Toner container having nozzle and projection at bottom of container and image forming system using container

Description:
TECHNICAL FIELD 
     The present invention relates to a toner container which can be mounted to an image forming apparatus and relates to an image forming system. 
     BACKGROUND OF THE INVENTION 
     A structure using a dismountable toner container for an image forming apparatus is known in order to supply toner for the electrophotographic image forming apparatus to the image forming apparatus (WO2020100699A2). 
     SUMMARY OF THE INVENTION 
     Problems to be Solved 
     Recently, there are various types of usage of image forming apparatus demanded by users. It is an object of the present invention to provide a new form of a toner container which can be mounted to an image forming apparatus. 
     Means for Solving Problem 
     The first aspect of the present invention is a toner container comprising an accommodating portion configured to accommodate toner; a discharge portion configured to be provided with an opening for discharging the toner in the accommodating portion to an outside; a rotatable member rotatable about a central axis as a rotational axis relative to the discharge portion in a first rotational direction and a second rotational direction opposite to the first rotational direction; and a projection provided below the opening of the discharge portion and having an inner peripheral surface facing inward in a radial direction of an imaginary circle centered on the central axis, when the toner container is oriented in a predetermined direction in which the central axis extends in a direction of gravity and at least a part of the discharge portion is below the accommodating portion, wherein the opening of the discharge portion faces in the radial direction, wherein when the toner container is oriented in the predetermined direction, the projection has a first downward surface and a second downward surface which face downward, and an upward surface which faces upward, outside the inner peripheral surface and inside the opening of the discharge portion in the radial direction, the first downward surface and the second downward surface extend so as to go up as goes in the first rotational direction, and at least a part of the first downward surface is provided at a position which is closer to the central axis in the radial direction than the second downward surface is and which is different from a position at which the second downward surface is provided in a circumferential direction of the imaginary circle, and at least a part of the upward surface is above at least a part of the second downward surface. 
     The Effect of the Invention 
     According to the present invention, it is possible to provide a new form of a toner container which can be mounted to an image forming apparatus. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         FIG.  1    is views of an image forming system according to Embodiment 1. 
         FIG.  2    is a perspective view of an image forming apparatus according to Embodiment 1. 
         FIG.  3    is exploded perspective views of a mounting portion in Embodiment 1. 
         FIG.  4    is external perspective views of the mounting portion in Embodiment 1. 
         FIG.  5    is top views of the mounting portion in Embodiment 1 as viewed from above. 
         FIG.  6    is a view of the mounting portion in Embodiment 1 as viewed from below. 
         FIG.  7    is perspective views of an apparatus-side shutter in Embodiment 1. 
         FIG.  8    is a perspective view of a cover in Embodiment 1. 
         FIG.  9    is cross-sectional views of the mounting portion in Embodiment 1 (when the shutter rotation on the apparatus-side is restricted). 
         FIG.  10    is sectional views of the mounting portion in Embodiment 1 (when the restriction of the apparatus-side shutter rotation is released). 
         FIG.  11    is perspective views of a restriction member in Embodiment 1. 
         FIG.  12    is perspective views of the releasing member used in Embodiment 1. 
         FIG.  13    is a perspective view and a front view of a unit in which the restriction member and the releasing member are assembled in Embodiment 1. 
         FIG.  14    is sectional views of the mounting portion in Embodiment 1. 
         FIG.  15    is sectional views of the mounting portion in Embodiment 1. 
         FIG.  16    is front views of a toner pack according to Embodiment 1. 
         FIG.  17    is an exploded perspective view of the toner pack according to Embodiment 1. 
         FIG.  18    is a perspective view and a bottom view of a neighborhood of a nozzle in Embodiment 1 (when the shutter on the pack side is closed). 
         FIG.  19    is a perspective view and a bottom view of the neighborhood of the nozzle according to Embodiment 1 (when the shutter on the pack side is opened). 
         FIG.  20    is a rear perspective view of the neighborhood of the nozzle in Embodiment 1. 
         FIG.  21    is a front view of the neighborhood of the nozzle in Embodiment 1. 
         FIG.  22    is a cross-section of a projecting portion of the nozzle in Embodiment 1. 
         FIG.  23    is perspective views of the mounting portion and the toner pack in a state during mounting operation in Embodiment 1. 
         FIG.  24    is a sectional view of the mounting portion and the toner pack in a state during mounting in Embodiment 1. 
         FIG.  25    is cross-sectional views of the mounting portion and the toner pack in a state during mounting in Embodiment 1. 
         FIG.  26    is an illustration of a process in which the rotation restriction of the shutter on the apparatus-side by the rotation restriction mechanism of the mounting portion is released by mounting the toner pack in Embodiment 1. 
         FIG.  27    is sectional views of the mounting portion and the toner pack at the time when the mounting portion of the toner pack according to Embodiment 1 is completed. 
         FIG.  28    is perspective views of the toner pack mounted on the mounting portion when an operating lever is in a closed position and an open position, as viewed from above. 
         FIG.  29    is sectional views illustrating a toner movement path when the apparatus-side shutter and the pack-side shutter are closed and opened. 
         FIG.  30    is perspective views of a neighborhood of the nozzle in Modified Example 1 of Embodiment 1. 
         FIG.  31    is perspective views of a neighborhood of the nozzle depending on Modified Example 2 of Embodiment 1. 
         FIG.  32    is a perspective view of the neighborhood of the nozzle in Modified Example 3 of Embodiment 1. 
         FIG.  33    is a perspective view and a front view of a neighborhood of the nozzle in Modified Example 4 of Embodiment 1. 
         FIG.  34    is front views of the toner pack in Modified Example 5 of Embodiment 1. 
         FIG.  35    is perspective views of a neighborhood of the nozzle in Modified Example 6 of Embodiment 1. 
         FIG.  36    is perspective views of a neighborhood of the nozzle in Modified Example 7 of Embodiment 1. 
         FIG.  37    is perspective views of a neighborhood of the nozzle in Modified Example 8 of Embodiment 1. 
         FIG.  38    is perspective views of the neighborhood of the nozzle and an attachment according to Modified Example 9 of Embodiment 1. 
         FIG.  39    is enlarged views of a second slope of the restriction releasing portion in Embodiment 1 and Modified Examples 1-9 of Embodiment 1. 
         FIG.  40    is exploded perspective views of the mounting portion in Embodiment 2. 
         FIG.  41    is external perspective views of the mounting portion in Embodiment 2. 
         FIG.  42    is views of the mounting portion in Embodiment 2 as viewed from above. 
         FIG.  43    is a view of the mounting portion in Embodiment 2 as viewed from below. 
         FIG.  44    is perspective views of an apparatus-side shutter in Embodiment 2. 
         FIG.  45    is perspective views of a cover in Embodiment 2. 
         FIG.  46    is perspective views of the restriction member in Embodiment 2. 
         FIG.  47    is perspective views of a releasing member in Embodiment 2. 
         FIG.  48    is perspective views of a unit in which a restriction member and a releasing member are assembled in Embodiment 2. 
         FIG.  49    is a sectional view of a mounting portion in Embodiment 2 (when the shutter rotation on the apparatus-side is restricted). 
         FIG.  50    is cross-sectional views illustrating a position of the releasing member relative to the restriction member in Embodiment 2. 
         FIG.  51    is sectional views of the mounting portion in Embodiment 2 (when the apparatus-side shutter rotation restriction is released). 
         FIG.  52    is sectional views illustrating a position of the releasing member relative to the restriction member in Embodiment 2. 
         FIG.  53    is sectional views illustrating a position of the releasing member relative to the restriction member in Embodiment 2. 
         FIG.  54    is cross-sectional views illustrating a position of the releasing member relative to the restriction member in Embodiment 2. 
         FIG.  55    is a front view, a rear view, and a side view of a toner pack according to Embodiment 2. 
         FIG.  56    is an exploded perspective view of the toner pack according to Embodiment 2. 
         FIG.  57    is a perspective view and a bottom view of the neighborhood of a nozzle in Embodiment 2 (when the shutter on the pack side is closed). 
         FIG.  58    is a perspective view, a bottom view, and a front view of the neighborhood of the nozzle in Embodiment 2 (when the shutter on the pack side is opened). 
         FIG.  59    is a rear perspective view of the neighborhood of the nozzle, an enlarged perspective view, and a front view of a projection in according to Embodiment 2. 
         FIG.  60    is a perspective view and a bottom view of the projecting portion in Embodiment 2. 
         FIG.  61    is a front view and a rear view of a neighborhood of the nozzle in Embodiment 2. 
         FIG.  62    is a cross-sectional view of a projecting portion of the nozzle and a bottom view of the nozzle in Embodiment 2. 
         FIG.  63    is perspective views of the toner pack and the mounting portion immediately before and at the time of completion of mounting of the toner pack according to Embodiment 2. 
         FIG.  64    is cross-sectional views of the mounting portion and the toner pack during mounting of the toner pack according to Embodiment 2. 
         FIG.  65    is an illustration showing a process in which the rotation restriction of the shutter on the apparatus-side by the rotation restriction mechanism of the mounting portion is released by mounting the toner pack in Embodiment 2. 
         FIG.  66    is an illustration showing a process of releasing the rotation restriction of the shutter on the apparatus-side by the rotation restriction mechanism of the mounting portion, by mounting the toner pack, in Embodiment 2. 
         FIG.  67    is enlarged perspective views of the mounting portion showing how a releasing claw of the releasing member is exposed through the central hole of the cover of the mounting portion in Embodiment 2. 
         FIG.  68    is sectional views of the mounting portion and the toner pack at the time of completing the mounting of the toner pack in Embodiment 2. 
         FIG.  69    the perspective views of the toner pack mounted to the mounting portion when the operating lever is in the closed position and the open position, as viewed from above. 
         FIG.  70    is sectional views illustrating a toner movement path when the apparatus-side shutter and the pack-side shutter are closed and opened. 
         FIG.  71    is a perspective view and a bottom view illustrating a structure of a modified example of the inner peripheral surface of the projecting portion of the nozzle. 
         FIG.  72    is a perspective view and a side view of an attachment according to the Modified Example 1 of Embodiment 2. 
         FIG.  73    is a top view and a cross-sectional view illustrating only the portions related with mounting of the attachment to the main assembly of the apparatus in Modified Example 1 of Embodiment 2. 
         FIG.  74    is sectional views illustrating a process of mounting the attachment to the apparatus main assembly according to Modified Example 1 of Embodiment 2. 
         FIG.  75    is sectional views illustrating a process of mounting the attachment to the apparatus main assembly according to Modified Example 1 of Embodiment 2. 
         FIG.  76    is a perspective view of the toner pack according to Modified Example 1 of Embodiment 2. 
         FIG.  77    is a side view and a sectional view of the toner pack mounted to the main assembly of the apparatus in Modified Example 1 of Embodiment 2. 
         FIG.  78    is a perspective view of an attachment including different shapes according to Modified Example 1 of Embodiment 2. 
         FIG.  79    is a perspective view and a side view of the attachment unit according to Modified Example 2 of Embodiment 2. 
         FIG.  80    is a perspective view of a shutter in Modified Example 2 of Embodiment 2. 
         FIG.  81    is a perspective view of a projecting member in Modified Example 2 of Embodiment 2. 
         FIG.  82    is an exploded perspective view of the attachment unit according to Modified Example 2 of Embodiment 2. 
         FIG.  83    is a cross-sectional view of a projecting member and a shutter when they are located at the first positions in Modified Example 2 of Embodiment 2. 
         FIG.  84    is a side view of the neighborhood of the projecting member in the state in which the operating lever is between the closed position and the open position in Modified Example 2 of Embodiment 2. 
         FIG.  85    is a cross-sectional view of the neighborhood of the projecting member in the state in which the operating lever is between the closed position and the open position in Modified Example 2 of Embodiment 2. 
         FIG.  86    is a perspective view of the toner pack mounted to the main assembly of the apparatus, according to Modified Example 2 of embodiment 2. 
         FIG.  87    is a perspective view of the attachment unit with the lid member mounted according to Modified Example 2 of Embodiment 2. 
         FIG.  88    is an illustration showing the detailed shapes of a first restriction releasing portion and the second restriction releasing portion in Modified Example 3 of Embodiment 2. 
         FIG.  89    is an illustration showing a process in which the releasing member is rotated by the first slope of the first restriction releasing portion in Modified Example 3 of Embodiment 2. 
         FIG.  90    is an illustration showing a process in which the releasing member is rotated by a second slope of a first restriction releasing portion in Modified Example 3 of Embodiment 2. 
         FIG.  91    is illustrations showing the detailed shapes of the first restriction releasing portion and the second restriction releasing portion in another form in Modified Example 3 of Embodiment 2. 
         FIG.  92    is illustrations showing a process in which the releasing member is rotated by the first restriction releasing portion and the second restriction releasing portion of another form of Modified Example 3 of Embodiment 2. 
         FIG.  93    is an external perspective view of a discharge unit according to Modified Example 4 of Embodiment 2. 
         FIG.  94    is an exploded perspective view of the discharge unit according to Modified Example 4 of Embodiment 2. 
         FIG.  95    is a perspective view of the toner pack equipped with the discharge unit according to Modified Example 4 of Embodiment 2. 
         FIG.  96    is a perspective view of the toner pack according to Modified Example 5 of Embodiment 2. 
         FIG.  97    is a perspective view and a sectional view of the nozzle in Modified Example 5 of Embodiment 2. 
         FIG.  98    is a perspective view and a cross-sectional view of the nozzle in Modified Example 5 of Embodiment 2 in a state in which the discharge opening faces downward. 
         FIG.  99    is a perspective view and a sectional view of the nozzle in Modified Example 5 of Embodiment 2 in a state in which the discharge opening faces a radially outer side. 
         FIG.  100    is illustrations showing a detailed shape of the first restriction releasing portion and the second restriction releasing portion according to Modified Example 6 of Embodiment 2. 
         FIG.  101    is a perspective view, a front view, a side view, and a rear view of the toner pack according to a Modified Example 7 of Embodiment 2. 
         FIG.  102    is a perspective view of a toner pack and a mounting portion, and a perspective view of a rod used for opening a shutter on the apparatus-side, according to Modified Example 7 of Embodiment 2. 
         FIG.  103    is an illustration showing an entire toner pack according to Embodiment 3. 
         FIG.  104    is an exploded perspective view of a nozzle and the portions assembled to the nozzle in Embodiment 3. 
         FIG.  105    is an exploded perspective view of the nozzle and the portions assembled to the nozzle in Embodiment 3. 
         FIG.  106    is an illustration showing a detailed shape of the restriction releasing member in Embodiment 3. 
         FIG.  107    is a sectional view of the toner pack according to Embodiment 3. 
         FIG.  108    is an illustration showing a process of operating the toner pack in Embodiment 3. 
         FIG.  109    is a sectional view of the toner pack according to Embodiment 3. 
         FIG.  110    is illustrations showing a process in which the rotation restriction of the shutter on the apparatus-side by the rotation restriction mechanism of the mounting portion is released by mounting the toner pack according to Embodiment 3. 
         FIG.  111    is an illustration showing a process in which the rotation restriction of the shutter on the apparatus-side by the rotation restriction mechanism of the mounting portion is released by mounting the toner pack in Embodiment 3. 
         FIG.  112    is an illustration showing a detailed shape of the restriction releasing member according to Modified Example 1 of Embodiment 3. 
         FIG.  113    is an illustration showing a detailed shape of the restriction releasing member in Modified Example 2 of Embodiment 3. 
         FIG.  114    is an illustration showing an entire toner pack according to Embodiment 4. 
         FIG.  115    is an exploded perspective view of a nozzle and the portions assembled to the nozzle in Embodiment 4. 
         FIG.  116    is a perspective view of the nozzle in Embodiment 4. 
         FIG.  117    is a perspective view of a movement path in Embodiment 4. 
         FIG.  118    is a perspective view of a cam member, an operating member, and a shaft member in Embodiment 4. 
         FIG.  119    is an illustration showing the assembly of the movement path and the tension spring to the nozzle in Embodiment 4. 
         FIG.  120    is an illustration showing a process of assembling the operation mechanism to the nozzle in Embodiment 4. 
         FIG.  121    is perspective views in a state in which portions are assembled to the nozzle, in Embodiment 4. 
         FIG.  122    is an illustration showing a state in which the pack-side shutter is in an open position and a closed position in a second position of the movement path in Embodiment 4. 
         FIG.  123    is an illustration showing the operation of the movement path by operating the operating member in Embodiment 4. 
         FIG.  124    is an illustration showing a process of inserting the toner pack into the mounting portion and operating the operation lever and the operating member according to Embodiment 4. 
         FIG.  125    is sectional views in which the toner pack is mounted to an attachment portion and the operation lever is in the open position, in Embodiment 4. 
         FIG.  126    is sectional views when the operating member is operated to move the movement path to the first position in Embodiment 4. 
         FIG.  127    is a perspective view of a toner pack according to Embodiment 5. 
         FIG.  128    is an exploded perspective view of the toner pack according to Embodiment 5. 
         FIG.  129    is a partially exploded perspective view of the toner pack according to Embodiment 5. 
         FIG.  130    is a partially exploded perspective view of the toner pack according to Embodiment 5. 
         FIG.  131    is a perspective view of a nozzle in Embodiment 5. 
         FIG.  132    is a sectional view and a side view of the nozzle in Embodiment 5. 
         FIG.  133    is a schematic perspective view illustrating the first operation of the user in Embodiment 5. 
         FIG.  134    is side views illustrating the second operation of the user in Embodiment 5. 
         FIG.  135    is a side view illustrating a third operation of the user according to Embodiment 5. 
         FIG.  136    is sectional views illustrating a third operation of the user in Embodiment 5. 
         FIG.  137    is a perspective view illustrating states before and after a toner seal is broken in Embodiment 5. 
         FIG.  138    is an external view of a toner pack having a structure in which the toner seal is pulled out, according to Embodiment 5. 
         FIG.  139    is an exploded perspective view illustrating an attachment of a toner seal of the toner pack in Embodiment 5. 
         FIG.  140    is a partially exploded perspective view illustrating the mounting of the toner seal of the toner pack according to Embodiment 5. 
         FIG.  141    is a sectional view of the toner pack according to Embodiment 5, which is structured to pull out the toner seal to the outside. 
         FIG.  142    is an illustration showing an entire toner pack according to Embodiment 6. 
         FIG.  143    is an exploded perspective view of the restriction releasing mechanism according to Embodiment 6. 
         FIG.  144    is an illustration showing a detailed shape of the restriction releasing mechanism and a process of an assembling method in Embodiment 6. 
         FIG.  145    is a sectional view of a toner pack according to Embodiment 6. 
         FIG.  146    is an illustration showing operation of a restriction releasing mechanism in Embodiment 6. 
         FIG.  147    is an enlarged perspective view of the neighborhood of a projecting portion of the toner pack according to Embodiment 6. 
         FIG.  148    is an illustration showing an entire toner pack according to Embodiment 7. 
         FIG.  149    is an exploded perspective view of a restriction releasing mechanism according to Embodiment 7. 
         FIG.  150    is a detailed view of a first restriction releasing member and a second restriction releasing member in Embodiment 7. 
         FIG.  151    is a sectional view of the toner pack according to Embodiment 7. 
         FIG.  152    is an illustration showing operation of the restriction releasing mechanism in Embodiment 7. 
         FIG.  153    is an illustration showing a process of releasing rotation restriction of a shutter on the apparatus-side by a rotation restriction mechanism of the mounting portion by mounting the toner pack, in Embodiment 7. 
         FIG.  154    is a detailed view of a first restriction releasing member and a second restriction releasing member in Modified Example 1 of Embodiment 7. 
         FIG.  155    is an illustration showing a process in which rotation restriction of a shutter on the apparatus-side by the rotation restriction mechanism of the mounting portion is released by mounting the toner pack in Modified Example 1 of Embodiment 7. 
         FIG.  156    is an exploded perspective view of a restriction releasing mechanism according to Modified Example 2 of Embodiment 7. 
         FIG.  157    is an illustration showing operation of the restriction releasing mechanism according to Modified Example 2 of Embodiment 7. 
         FIG.  158    is an illustration showing a process in which rotation restriction of the shutter on the apparatus-side by the rotation restriction mechanism of the mounting portion is released by mounting the toner pack in Modified Example 2 of Embodiment 7. 
         FIG.  159    is an exploded perspective view of the restriction releasing mechanism in Modified Example 3 of Embodiment 7. 
         FIG.  160    is an illustration showing a process in which the rotation restriction of the shutter on the apparatus-side by the rotation restriction mechanism of the mounting portion is released by mounting the toner pack in Modified Example 3 of Embodiment 7. 
         FIG.  161    is an illustration showing a position of a pin provided on a straight portion when the toner pack is mounted on the mounting portion in Modified Example 3 of Embodiment 7. 
         FIG.  162    is an illustration showing an entire toner pack according to Embodiment 8. 
         FIG.  163    is an exploded perspective view before a restriction releasing member and a shaft ring are assembled to the nozzle in Embodiment 8. 
         FIG.  164    is a detailed view of the restriction releasing member in Embodiment 8. 
         FIG.  165    is sectional views of the restriction releasing member in Embodiment 8. 
         FIG.  166    is a sectional view of the toner pack according to Embodiment 8. 
         FIG.  167    is an illustration showing a process of releasing rotation restriction of a shutter on the apparatus-side by the rotation restriction mechanism of the mounting portion by mounting the toner pack, according to Embodiment 8. 
         FIG.  168    is an illustration showing a process in which rotation restriction of the shutter on the apparatus-side by the rotation restriction mechanism of the mounting portion is released by mounting the toner pack, in Embodiment 8. 
         FIG.  169    is an illustration showing a process in which rotation restriction of the shutter on the apparatus-side by the rotation restriction mechanism of the mounting portion is released by mounting the toner pack, in Embodiment 8. 
         FIG.  170    is an illustration showing a process of releasing rotation restriction of the shutter on the apparatus-side by a rotation restriction mechanism of the mounting portion by mounting the toner pack, according to Embodiment 8. 
         FIG.  171    is an illustration showing a process in which rotation restriction of the shutter on the apparatus-side by the rotation restriction mechanism of the mounting portion is released by mounting the toner pack, in Embodiment 8. 
         FIG.  172    is an illustration showing a process in which rotation restriction of the shutter on the apparatus-side by the rotation restriction mechanism of the mounting portion is released by mounting the toner pack, in Embodiment 8. 
         FIG.  173    is a perspective view of a restriction releasing member in Modified Example 1 of Embodiment 8. 
         FIG.  174    is a detailed view of the restriction releasing member in Modified Example 2 of Embodiment 8. 
         FIG.  175    is a detailed view of a restriction releasing member according to Modified Example 3 of Embodiment 8. 
         FIG.  176    is a perspective view of a toner pack according to Embodiment 9. 
         FIG.  177    is an exploded perspective view of the toner pack according to Embodiment 9. 
         FIG.  178    is an exploded perspective view of a nozzle according to Embodiment 9. 
         FIG.  179    is exploded perspective views of a pack-side shutter according to Embodiment 9. 
         FIG.  180    is top views and side views illustrating a state in which the toner pack is mounted on the mounting portion in Embodiment 9. 
         FIG.  181    is sectional views in a state in which the toner pack is mounted to the mounting portion in Embodiment 9. 
         FIG.  182    is sectional views of the state in which the toner pack is mounted on the mounting portion according to Embodiment 9. 
         FIG.  183    is a perspective view of the toner pack according to Embodiment 10. 
         FIG.  184    is an exploded perspective view of the toner pack according to Embodiment 10. 
         FIG.  185    is an exploded view of a nozzle in Embodiment 10. 
         FIG.  186    is exploded perspective views of a pack-side shutter according to Embodiment 10. 
         FIG.  187    is a side view and a sectional view of the toner pack according to Embodiment 10. 
         FIG.  188    is a top view, a side view, and a sectional view illustrating a state in which the toner pack is mounted to the mounting portion in Embodiment 10. 
         FIG.  189    is cross-sectional views illustrating a state in which the toner pack is mounted to the mounting portion in Embodiment 10. 
         FIG.  190    is a top view, a side view, and a cross-sectional view illustrating a state in which toner in the toner pack is supplied into a toner accommodating chamber of a developer container in Embodiment 10. 
         FIG.  191    is a cross-sectional view illustrating a state in which the toner of the toner pack is supplied into the toner accommodating chamber of the developer container in Embodiment 10. 
         FIG.  192    is a perspective view of a state in which a free end member of the toner pack is in a first attitude in Embodiment 11. 
         FIG.  193    is a partially exploded perspective view of a toner pack according to Embodiment 11. 
         FIG.  194    is an exploded perspective view of a projecting member in Embodiment 11. 
         FIG.  195    is a side view and a sectional view illustrating a user operation of the projecting member in Embodiment 11. 
         FIG.  196    is an illustration showing a structure in which only one restriction releasing portion of the projecting portion in Embodiment 2 and a structure in which the second restriction releasing portion has a shape of 190-degree rotational symmetry of the first restriction releasing portion. 
     
    
    
     EMBODIMENTS OF THE INVENTION 
     Hereinafter, exemplary embodiments for implementing the present invention will be described with reference to the accompanying drawings. 
     Embodiment 1 
     Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 
     (Image Forming Apparatus System) 
     Part (a) of  FIG.  1    is a schematic cross-sectional view illustrating a structure of an image forming system  1000  according to Embodiment 1. Part (b) of  FIG.  1    is a perspective view of the image forming system  1000 . 
     The image forming system  1000  includes an image forming apparatus  1  and a toner pack  100  (toner container, toner cartridge) which can be mounted to the image forming apparatus  1 .  FIG.  2    is a perspective view of the image forming apparatus  1  to which the toner pack  100  is not mounted. 
     The toner pack  100  is mountable to the mounting portion  106  of the image forming apparatus  1  shown in  FIG.  2    and contains toner to be supplied to the image forming apparatus  1 . The detailed structure of the toner pack  100  will be described hereinafter. The toner pack  100  is mounted by moving it in the mounting direction M shown in  FIG.  2   . In this embodiment, the mounting direction M of the toner pack  100  is the direction of gravity, but the direction M may be inclined relative to the direction of gravity. 
     (Image Forming Apparatus) 
     The image forming apparatus  1  is a monochromatic printer which forms an image on the recording material P based on the image information inputted from an external device. The recording material P may be various sheet materials such as papers such as plain paper and thick paper, plastic films such as sheets for overhead projectors, sheets having a special shape such as envelopes and index papers, or various sheet materials made of different materials such as cloth. 
     As shown in part (a) of  FIG.  1    and part (b) of  FIG.  1   , the image forming apparatus  1  has the following structure. It comprises an image forming portion  10  that forms a toner image on the recording material P, a pickup roller  65  that feeds the recording material P to the image forming portion  10 , a fixing portion  70  that fixes the toner image formed by the image forming portion  10 , on the recording material P, and the discharging roller pair  80 . 
     The image forming portion  10  includes a scanner unit  11 , an electrophotographic process unit  20   a  transfer roller  12  that transfers a toner image as a developer image formed on a photosensitive drum  21  of the process unit  20  to the recording material P. The process unit  20  includes a photosensitive drum  21 , a charging roller  22 , a pre-exposure portion  23 , and a developing device  30  (developing unit, developing portion) including a developing roller  31 . 
     The photosensitive drum  21  (image bearing member) is a photosensitive member molded into a cylindrical shape. The photosensitive drum  21  of this embodiment has a photosensitive layer formed of a negatively charged organic photosensitive member on a drum-shaped substrate made of aluminum. Further, the photosensitive drum  21  is rotationally driven by a motor in a predetermined rotational direction (clockwise direction in the Figure) at a predetermined process speed. 
     The charging roller  22  contacts the photosensitive drum  21  with a predetermined pressure contact force to form a charging portion. Further, by applying a desired charging voltage by a charging high voltage power source, the surface of the photosensitive drum  21  is uniformly charged to a predetermined potential. In this embodiment, the photosensitive drum  21  is charged by the charging roller  22  to the negative polarity. The pre-exposure portion  23  removes static electricity from the surface potential of the photosensitive drum  21  before reaching the charging portion in order to generate a stable discharge in the charging portion. 
     The scanner unit  11  as an exposure means scans and exposes a surface of the photosensitive drum  21  by irradiating the photosensitive drum  21  with a laser beam corresponding to image information inputted from an external device, using a polygonal mirror. By this exposure, an electrostatic latent image corresponding to the image information is formed on the surface of the photosensitive drum  21 . The scanner unit  11  is not limited to the laser scanner device, and, for example, an LED exposure device including an LED array in which a plurality of LEDs are arranged along the longitudinal direction of the photosensitive drum  21  may be employed. 
     The developing device  30  includes a developing roller  31  for supplying the developer to the developing roller  31  as a developer carrying member for carrying the developer, a developer container  32  (developing frame) which is the frame of the developing device  30 , and a supply roller  33  capable of supplying the developer to the developing roller  31 . The developing roller  31  and the supply roller  33  are rotatably supported by the developer container  32 . In addition, the developing roller  31  is arranged in the opening of the developer container  32  so as to face the photosensitive drum  21 . The supply roller  33  is rotatably in contact with the developing roller  31 , and the toner as a developer contained in the developer container  32  is supplied to the surface of the developing roller  31  by the supply roller  33 . The supply roller  33  is not always required, if the toner can be sufficiently supplied to the developing roller  31 . 
     The developing device  30  of this embodiment uses a contact developing method as a developing method. That is, a toner layer carried on the developing roller  31  is in contact with the photosensitive drum  21  in a developing portion (developing region) where the photosensitive drum  21  and the developing roller  31  face each other. A developing voltage is applied to the developing roller  31  by a developing high voltage power source. Under the developing voltage, the toner carried on the developing roller  31  is transferred from the developing roller  31  to the drum surface in accordance with the potential distribution on the surface of the photosensitive drum  21 , so that the electrostatic latent image is developed into a toner image. In this embodiment, a reverse development method is employed. That is, the surface of the photosensitive drum is charged in the charging step and then a charge amount is attenuated by the exposure in the exposure step, and the toner adheres to the surface region of the photosensitive drum  21  having the attenuated charge amount, so that a toner image is formed. 
     Further, in this embodiment, a toner having a particle size of 6 μm and a negative regular charge polarity is used. As an example, the toner of this embodiment employs a polymerized toner produced by a polymerization method. In addition, the toner of this embodiment does not contain a magnetic component, and is a so-called non-magnetic one-component developer in which the toner is supported on the developing roller  31  mainly by an intermolecular force or an electrostatic force (mirror image force). However, a one-component developer containing a magnetic component may be used. In addition to the toner particles, the one-component developer may contain additives (for example, wax or silica fine particles) for adjusting the fluidity and charging performance of the toner. Furthermore, as the developer, a two-component developer comprising a non-magnetic toner and a magnetic carrier may be used. When a magnetic developer is used, for example, a cylindrical developing sleeve in which a magnet is arranged inside is used as the developer carrier. 
     The developer container  32  includes a toner accommodating chamber  36  (second accommodating portion, main assembly accommodating portion) for accommodating toner. A stirring member  34  (toner transporting member) is provided inside the toner accommodating chamber  36 . The stirring member  34  is driven by a motor (not shown) to stir the toner in the developer container  32 , and at the same time, feed the toner toward the developing roller  31  and the supply roller  33 . In addition, the stirring member  34  functions to circulate the toner not used for development but stripped off the developing roller  31  in the developer container, thus making uniform the toner in the developer container. The stirring member  34  is not limited to the rotating type. For example, a stirring member including a swinging shape may be employed instead. 
     Further, a developing blade  35  that restricts the amount of toner carried on the developing roller  31  is arranged in the opening of the developer container  32  in which the developing roller  31  is arranged. The toner supplied to the surface of the developing roller  31  passes through the portion facing the developing blade  35  with the rotation of the developing roller  31 , so that the toner is uniformly formed into a thin layer and is charged to the negative polarity by triboelectric charging. 
     Next, the image forming operation of the image forming apparatus  1  will be described. When a command for image formation is inputted to the image forming apparatus  1 , the image forming process by the image forming portion  10  is started based on the image information inputted from an external computer connected to the image forming apparatus  1 . The scanner unit  11  irradiates the photosensitive drum  21  with a laser beam based on the inputted image information. At this time, the photosensitive drum  21  is precharged by the charging roller  22 , and the electrostatic latent image is formed on the photosensitive drum  21  by being irradiated with the laser beam. Thereafter, the electrostatic latent image is developed by the developing roller  31 , and a toner image is formed on the photosensitive drum  21 . 
     In parallel with the image forming process described above, the recording material P is fed out by the pickup roller  65  and is fed toward the transfer nip formed by the transfer roller  12  and the photosensitive drum  21 . 
     The transfer roller  12  is supplied with a transfer voltage from a transfer high-voltage power source, so that the toner image carried on the photosensitive drum  21  is transferred onto the recording material P. When the recording material P now carrying the toner image passes through the fixing portion  70 , the toner image is heated and pressed. By this, the toner particles are melted and then fixed, so that the toner image is fixed on the recording material P. The recording material P which has passed through the fixing portion  70  is discharged to the outside (outside the machine) of the image forming apparatus  1  by the discharging roller pair  80  as the discharging means, on the discharge tray  81  as a stacking portion provided at an upper portion of the image forming apparatus  1 . 
     A top cover  82  as a stacking tray is provided at the upper portion of the image forming apparatus  1 , and the discharge tray  81  as a stacking surface is formed at the upper surface of the top cover  82 . As shown in part (b) of  FIG.  1    and  FIG.  2   , the top cover  82  is provided with an opening/closing member  83  which is supported so as to be openable/closable around a rotation shaft  83   a  extending in the front-rear direction. The discharge tray  81  of the top cover  82  is provided with an opening  82   a  which opens upward. As shown in  FIG.  2   , the mounting portion  106  for mounting the toner pack  100  is exposed through the opening  82   a.    
     The opening/closing member  83  is movable between a closed position for covering the mounting portion  106  in which the toner pack  100  cannot be mounted to the image forming apparatus  1 , and an open position in which the mounting portion  106  is exposed so that the toner pack  100  can be mounted to the image forming apparatus  1 . The opening/closing member  83  functions as a part of the discharge tray  81  in the closed position. The opening/closing member  83  and the opening  82   a  are formed on the left side of the discharge tray  81  as viewed from the front of the image forming apparatus  1 . The front side of the image forming apparatus  1  described here is the upstream side of the image forming apparatus  1  in the direction in which the recording material P is fed out by the pickup roller  65 . In addition, the opening/closing member  83  is opened to the left by hooking a finger in the groove portion  82   b  provided in the top cover  82 . 
     The opening  82   a  of the discharge tray  81  is opened so that the mounting portion  106  formed on the upper portion of the image forming apparatus  1  is exposed, and by opening the opening/closing member  83 , the user can access the mounting portion  106 . In this embodiment, the direct supply method in which the user supplies the toner from the toner pack  100  mounted on the mounting portion  106  to the developing device  30  while the developing device  30  is mounted in the image forming apparatus  1  is employed. At least a part of the toner pack  100  is exposed to the outside of the image forming apparatus  1  in a state of being mounted to the mounting portion  106  of the image forming apparatus  1 . 
     When the remaining amount of toner in the process unit  20  is low, it is not necessary to take out the process unit  20  from the image forming apparatus  1  and replace it with a new process unit, so that usability can be improved. Further, the toner can be replenished to the developer container  32  at a lower cost than replacing the entire process unit  20 . In the direct supply method, it is not necessary to replace various rollers, gears, and so on, and therefore, the cost can be reduced, as compared with the case where only the developing device  30  of the process unit  20  is replaced, as well. 
     (Toner Pack Mounting Portion) 
     First, referring to  FIGS.  3  to  8   , the structure of the mounting portion  106  will be described. In this embodiment, the mounting portion  106  is a unit for mounting the toner pack  100 . 
     Part (a) of  FIG.  3    is an exploded perspective view of the mounting portion  106 . Part (b) of  FIG.  3    is an exploded perspective view of the mounting portion  106  as viewed in a direction different from that of part (a) of  FIG.  3   . Part (a) of  FIG.  4    and part (a) of  FIG.  5    are a perspective view illustrating the appearance of the mounting portion  106  when the operating lever  108  is in the closed position, and a view of the mounting portion  106  as viewed in the mounting direction M, respectively. Part (b) of  FIG.  4    and part (b) of  FIG.  5    are a perspective view illustrating the appearance of the mounting portion  106  when the operating lever  108  is in an open position, and a view of the mounting portion  106  as viewed in the mounting direction M, respectively.  FIG.  6    is a perspective view of the mounting portion  106  as viewed from the downstream side in the mounting direction M. 
     Part (a) of  FIG.  7    is a perspective view of the apparatus-side shutter  109  as viewed from the upstream side in the mounting direction M. Part (b) of  FIG.  7    is a perspective view of the apparatus-side shutter  109  as viewed from a point different from that of part (a) of  FIG.  7   . Part (a) of  FIG.  8    is a perspective view of a cover  110  as viewed from the downstream side of the cover  110  in the mounting direction M. Part (b) of  FIG.  8    is a perspective view of the cover  110  as viewed from the upstream side in the mounting direction M. 
     The mounting portion  106  shown in  FIGS.  3  and  4    is provided with a base frame  2  including a first frame  107 , a second frame  117 , and the cover  110 . The cover  110  and the second frame  117  are fixed to the first frame  107 . As shown in  FIG.  8   , the cover  110  includes an engaged portion  110   h  which engages with the engaging portion  107   b  (part (a) of  FIG.  3    of the first frame  107  so as not to rotate about the rotational axis B relative to the first frame  107 . The first frame  107 , the cover  110 , and the second frame  117  may be integrally structured instead of being separate members. As shown in  FIGS.  3  and  6   , the second frame  117  is provided with an apparatus-side opening  117   a  (frame opening, receiving opening), and the apparatus-side opening  117   a  is in fluid communication with a toner accommodating chamber  36  of the developing device  30  (see part (a) of  FIG.  1   ). 
     The operating lever  108  and the apparatus-side shutter  109  (second shutter) are mounted to the base frame  2  so as to be rotatable about the rotational axis B (central axis). 
     The first frame  107  is provided with a positioning portion  107   a . The positioning portion  107   a  projects inward from the inner peripheral surface of the first frame  107  centered on the rotational axis B in the radial direction r of an imaginary circle VC centered on the rotational axis B. Further, the operating lever  108  is provided with a drive transmission portion  108   a  (lever projection) and an operating portion  108   b . As shown in part (a) of  FIG.  3   , the drive transmission portion  108   a  of the operating lever  108  a projection portion which projects inward beyond an inner peripheral surface centered on the rotational axis B of the operating lever  108  in the radial direction r of the imaginary circle VC centered on the rotational axis B. 
     The apparatus-side shutter  109  is a cylindrical member having an open upper portion, and as shown in  FIG.  7   , it is provided with a receiving opening  109   a  (second shutter opening, apparatus-side shutter opening) in a lateral side surface, extending in the rotational axis B direction, of the apparatus side shutter, and it has a bottom surface  109   b  provided with a restricted rib  109   c  (rotation restricted portion). The apparatus-side shutter  109  further includes a center boss  109   d  (positioning shaft, shaft portion), a driven transmission portion  109   e  (pushed portion, apparatus-side shutter projection), a pack contact surface  109   g  (mounting direction positioning), and an inner peripheral surface  109   h  (positioning in the radial direction). The apparatus-side shutter  109  is structured to be rotatable about the rotational axis B relative to the base frame  2 . 
     The restricted rib  109   c  projects upward from the bottom surface  109   b  in the direction of the rotational axis B. As shown in part (a) of  FIG.  7   , the driven transmission portion  109   e  is a projection projecting inward in the radial direction r of the imaginary circle VC centered on the rotational axis B. An apparatus-side seal  111  is mounted around the receiving opening  109   a  (see part (b) of  FIG.  4   . 
     Here, the apparatus-side shutter  109  is structured so as to be rotatable relative to the base frame  2  between a closed position in which the receiving opening  109   a  is covered by the apparatus-side seal  111  and the cover  110 , and an open position in which it is open, not covered by the cover  110  and is opened. The closed position is the position shown in part (a) of  FIG.  4    and part (a) of  FIG.  5   , and is a position (non-communication position) in which the receiving opening  109   a  of the apparatus-side shutter  109  is not in fluid communication with the apparatus-side opening  117   a  of the second frame  117 . The open position is the position shown in part (b) of  FIG.  4    and part (b) of  FIG.  5   , and is a position (communication position) in which the receiving opening  109   a  of the apparatus-side shutter  109  is in fluid communication with the apparatus-side opening  117   a  of the second frame  117 . By moving the apparatus-side shutter  109  to the open position, the toner can be supplied (supplied) from the toner pack  100  into the toner accommodating chamber  36  of the developing device  30  through the receiving opening  109   a.    
     The drive of the operating lever  108  and the apparatus-side shutter  109  is not connected for drive transmission, and therefore, the apparatus-side shutter  109  does not rotate even if the operating lever  108  is operated without the toner pack  100  mounted. 
     (Apparatus-Side Shutter Rotation Restriction Mechanism) 
     As shown in  FIG.  3   , the mounting portion  106  of the image forming apparatus  1  further comprises a rotation restricting mechanism  112  including a restricting member  113  (rotation restriction member), a releasing member  114 , a restriction spring  115 , and a release spring  116 . 
     Referring to  FIGS.  9  to  15   , the rotation restricting mechanism  112  will be described. In  FIGS.  9 ,  10  and  14   , the cut surfaces of the cover  110 , the restricting member  113 , and the releasing member  114  are shaded for better illustration. 
     It may happen that in a state where the toner pack  100  is not mounted on the mounting portion  106 , the apparatus-side shutter  109  is unintentionally moved from the closed position to the open position due to an impact during transportation of the image forming apparatus  1  or due to an erroneous operation by the user with the consequence that it is rotated beyond a predetermined degree. In such a case, it may be difficult for the user to mount the toner pack  100  on the mounting portion  106  when using the image forming apparatus  1 . Details on this point will be described hereinafter. Therefore, the image forming apparatus  1  of this embodiment is provided with a rotation restricting mechanism  112  in order to prevent the shutter  109  on the apparatus side from rotating from the closed position to the open position. 
       FIGS.  9  and  10    are sectional views of the mounting portion  106 . Part (a) of  FIG.  9    is a sectional view taken along a line parallel to the rotational axis B in a state in which the rotation of the apparatus-side shutter  109  from the closed position to the open position is restricted by the rotation restricting mechanism  112 . Part (b) of  FIG.  9    is a cross-sectional view taken along the line X 1 -X 1  in part (a) of  FIG.  9   . Part (a) of  FIG.  10    is a sectional view taken along a line parallel to the rotational axis B in a state in which the rotation restriction of the apparatus-side shutter  109  by the rotation restricting mechanism  112  is released. Part (b) of  FIG.  10    is a cross-sectional view taken along the line X 2 -X 2  of part (a) of  FIG.  10   .  FIG.  10    shows, for convenience of the explanation, the state of the mounting portion  106  in which the rotation restriction of the apparatus-side shutter  109  is released in the state in the toner pack  100  is not mounted. 
     Further, part (a) of  FIG.  11    is a perspective view of the restricting member  113  as viewed from the upstream side in the mounting direction M. Part (b) of  FIG.  11    is a perspective view of the restricting member  113  as viewed from the downstream side in the mounting direction. Part (a) of  FIG.  12    is a perspective view of the releasing member  114  as viewed from the upstream side in the mounting direction M. Part (b) of  FIG.  12    is a perspective view of the releasing member  114  as viewed from the downstream side in the mounting direction M. Part (a) of  FIG.  13    is a perspective view of a unit in which the restricting member  113  and the releasing member  114  are assembled. Part (b) of  FIG.  13    is a sectional view, taken along a line parallel to the rotational axis B, of a unit in which the restricting member  113  and the releasing member  114  are assembled. 
     As shown in part (a) of  FIG.  9   , a restricting member  113 , a releasing member  114 , a restriction spring  115 , and a release spring  116  are provided inside the apparatus-side shutter  109 . 
     As shown in  FIG.  11   , the restricting member  113  is an annular member provided with a central hole  113   i  centered on the rotational axis B. The restricting member  113  includes a lower surface  113   a , a pair of first contact surfaces  113   b , a second contact surface  113   h , a second restricting surface  113   c  (rotation restriction portion), contacted surfaces  113   e , and a pair of locked surfaces  113   f , and a spring engagement portion  113   g . The first contact surface  113   b  and second contact surface  113   h  constituting a pair are downstream end surfaces in the rotational direction D of the apparatus-side shutter  109 . The second restricting surface  113   c  is an end surface on the downstream side in the rotational direction E of the apparatus-side shutter  109 . The locked surface  113   f  is an end surface (upper surface) on the upstream side in the mounting direction M. The lower surface  113   a  is an end surface on the downstream side in the mounting direction M. The spring engagement portion  113   g  is a projection projecting in the rotational direction E. 
     As shown in  FIG.  12   , the releasing member  114  (guided member) is provided with a pair of releasing claws  114   e  (engagement claws) extending upward, and is provided with a central hole  114   i  centered on the rotational axis B is provided. The releasing member  114  includes a pair of contact surfaces  114   a , a contact surface  114   b , a pair of rise restricted surfaces  114   c , a pair of locking surfaces  114   d , and a pair of releasing claws  114   e  (engaged portions), a pair of contact surfaces  114   f  and a spring engagement portion  114   g . The pair of contact surfaces  114   a  are end surfaces on the downstream side in the rotational direction E of the apparatus-side shutter  109 . The contact surface  114   b  is an end surface (upper surface) on the upstream side in the mounting direction M. The contact surface  114   f  is an end surface on the downstream side in the rotational direction E with respect to the contact surface  114   a . The rise restricted surface  114   c  is a surface connecting the contact surface  114   a  and the contact surface  114   f , and is an end (end surface facing upward) surface on the upstream side in the mounting direction M. The locking surface  114   d  is a surface (a surface facing downward) which projects from the outer peripheral surface of the releasing member  114  and faces in the mounting direction M. 
     As shown in  FIG.  13   , when the restricting member  113  and the releasing member  114  are assembled, the locked surface  113   f  of the restricting member  113  is directly below the locking surface  114   d  of the releasing member  114 , and faces the locking surface  114   d . In addition, the releasing claw  114   e  projects upward from the central hole centered on the rotational axis B of the restricting member  113  beyond the upper surface of the restricting member  113 . 
     As shown in part (a) of  FIG.  9    and part (b) of  FIG.  9   , the restricting member  113  and the releasing member  114  are rotatably supported by the large diameter portion  109   d   1  of the center boss  109   d  of the apparatus-side shutter  109 . Further, the rotation restricting mechanism  112  is covered by the upper surface  110   i  of the cover  110 . The center boss  109   d  is provided coaxially with the rotational axis B of the apparatus-side shutter  109 . The restricting member  113  is urged in the direction of arrow C of the direction of the rotational axis B by the urging force F 1  of the restricting spring  115  (second elastic member, second urging member), and the lower surface  113   a  thereof contacts the bottom surface  109   b  of the apparatus-side shutter  109 . The position of the restriction member at this time is a restriction position. The arrow C direction is the mounting direction M of the toner pack  100 . Further, as shown in part (b) of  FIG.  9   , a release spring  116  (first elastic member, first urging member) is provided between the restricting member  113  and the releasing member  114  in the rotational direction of the apparatus-side shutter  109 . One end and the other end of the release spring  116  are engaged with the spring engagement portion  113   g  of the restricting member  113  and the spring engagement portion  114   g  of the releasing member  114 , respectively. By the urging force F 2  of the release spring  116 , the restricting member  113  receives moment M 1  in the rotational direction D, So that at least one of the pair of first contact surfaces  113   b  contacts the corresponding first contact surface  110   a  of the cover  110 . The second contact surface  113   h  of the restricting member  113  contacts the contacted surface  110   j  (see  FIG.  8   ) of the cover  110 , so that the rotation in the rotational direction D is restricted. On the other hand, the releasing member  114  receives moment M 2  in the rotational direction E by the urging force F 3  of the release spring  116 , so that at least one of the pair of contact surfaces  114   a  contacts the corresponding second contacted surface  110   b  of the cover  110 . 
     Here, the cover  110  is integrally fixed to the first frame  107 . Therefore, as shown in part (b) of  FIG.  9   , the restricted rib  109   c  of the apparatus-side shutter  109  is between the first restriction surface  110   c  of the cover  110  and the second restricting surface  113   c  of the restricting member  113 . Therefore, the rotation of the apparatus-side shutter  109  in the rotational direction D (direction from the closed position to the open position) is restricted by the second restricting surface  113   c  of the restricting member  113 . The rotation of the apparatus-side shutter  109  in the rotational direction E (direction from the open position to the closed position) is restricted by the first restriction surface  110   c  of the cover  110 . 
     (Rotation Restriction Releasing Method) 
     A method of releasing the rotation restriction of the apparatus-side shutter  109  by the rotation restricting mechanism  112  will be described. The first step of rotating the releasing member  114  in the rotational direction D against the moment M 2  by the release spring  116  from the state of part (b) of  FIG.  9    is carried out, and then, the second step of moving the releasing member  114  is in an arrow G direction shown in part (a) of  FIG.  9    is carried out. The first step and the second step are performed by mounting the toner pack  100  onto the mounting portion  106 , which will be described after the structure of the toner pack  100  is described. Here, the description will be made using only the structure of the mounting portion  106 . 
     In the second step, the contact surface  114   b  of the releasing member  114  is brought into abutment to the contacted surface  113   e  of the restricting member  113 , and the releasing member  114  and the restricting member  113  are integrally moved in the direction of arrow G against the urging force F 1  of the restriction spring  115 . By executing the second step, the rotation restriction is released as shown in  FIG.  10   . The arrow G direction is the direction opposite to the mounting direction M of the toner pack  100 . 
     In the state where the rotation restriction is released, as shown in part (b) of  FIG.  10   , the second restricting surface  113   c  of the restricting member  113  retracts from the movement locus (rotation locus) of the restricted rib  109   c  of the apparatus-side shutter  109 . The position of the restricting member  113  at this time is a restriction release position (release position). Then, the restricted rib  109   c  becomes movable between the first restriction surface  110   c  and the third restriction surface  110   d  of the cover  110 . The distance between the first restriction surface  110   c  and the third restriction surface  110   d  is such that the apparatus-side shutter  109  can rotate and move between the closed position and the open position, and therefore, the rotation restriction of the apparatus-side shutter  109  is released. The apparatus-side shutter  109  becomes rotatable from the closed position to the open position in the rotational direction D about the rotational axis B. On the other hand, the rotation of the shutter  109  on the apparatus-side from the closed position in the direction opposite to the rotational direction D is restricted by the first restriction surface  110   c  of the cover  110 . The amount of movement of the releasing member  114  in the arrow G direction (upward direction) suffices if it is not less than such an amount that the second restricting surface  113   c  of the restricting member  113  in during moving with the releasing member  114  does not overlap with the restricted rib  109   c  of the apparatus-side shutter  109 , in the direction of the rotational axis B. 
     Here, the description will be made as to the structure of the rotation restricting mechanism  112  by which the rotation restriction of the apparatus-side shutter  109  is not released when the rotation restricting mechanism  112  is carried out from the second step without carrying out the first step. 
     Part (a) of  FIG.  14    is a sectional view taken along a line X 3 -X 3  in part (b) of  FIG.  9   . Part (b) of  FIG.  14    is a sectional view taken along the line X 3 -X 3  when the restricting member  113  is moved in the direction of arrow G without rotating the releasing member  114  in the rotational direction D from the state of part (a) of  FIG.  14   . 
     As shown in part (a) of  FIG.  14    and part (a) of  FIG.  8   , the cover  110  is provided with a rise restricting surface  110   e  (rising restricting section). As shown in part (a) of  FIG.  14    and part (a) of  FIG.  12   , the releasing member  114  is provided with an rise restricted surface  114   c  (rising restricted portion). When the restricting member  113  moves in the direction of arrow G in a state in which the second contact surface  110   b  and the contact surface  114   a  are in contact with each other as shown in part (b) of  FIG.  9   , the locked surface  113   f  of the restricting member  113  is brought into abutment to the locking surface  114   d  of the releasing member  114 . The same structure is provided on the opposite side with respect to the rotational axis B as the center, and therefore, the restricting member  113  and the releasing member  114  are integrally moved in the direction of arrow G (upward). As a result, as shown in part (b) of  FIG.  14   , the rise restricted surface  114   c  of the releasing member  114  abuts on the rise restricting surface  110   e  of the cover  110  so that the movement thereof in the G direction is restricted, by which the movement, in the arrow G direction, of the restricting member  113  integrally moving with the releasing member  114  is restricted. At this time, the restricted rib  109   c  of the apparatus-side shutter  109  is maintained in a rotation restricted state by the first restriction surface  110   c  and the second restricting surface  113   c  as shown in part (b) of  FIG.  9   . The position (region), in the rotational direction about the rotational axis B, of the releasing member  114  at this time is the rise restriction position (rise restriction region). That is, the rise restricting position is the position (region) of the releasing member  114  at the time when the rise restricted surface  114   c  of the releasing member  114  overlaps with the rise restricting surface  110   e  of the cover  110  as viewed in the direction of the rotational axis B. 
     The first step is a step of rotating the releasing member  114  in the rotational direction D against the urging force of the release spring  116  to the rise restriction release position (rise restriction release region) in which the rise restricted surface  114   c  of the releasing member  114  does not abut to the rise restricting surface  110   e  of the cover  110 . 
     Part (a) of  FIG.  15    is a cross-section taken along a line X 22 -X 22  of part (a) of  FIG.  10   . Part (a) of  FIG.  15    is an illustration showing a state in which the second step is performed after the first step. The second step of this embodiment includes the operation in which the releasing member  114  is rotated in the rotational direction E until at least one of the pair of contact surfaces  114   f  of the releasing member  114  abuts to the corresponding one of the pair of second contacted surfaces  110   b  of the cover  110 . Part (b) of  FIG.  15    is a cross-section taken along a line X 111 -X 111  of part (a) of  FIG.  15   . 
     As shown in part (a) of  FIG.  15   , as viewed in the direction of the rotational axis B, the rise restricted surface  114   c  of the releasing member  114  and the rise restricting surface  110   e  of the cover  110  do not overlap with each other. Therefore, as shown in part (b) of  FIG.  15   , the restricting member  113  can move integrally with the releasing member  114  in the direction of arrow G, the position of the releasing member  114  in the rotational direction about the rotational axis B is the rise restriction release position. That is, as viewed in the direction of the rotational axis B, the rise restriction release position is the position of the releasing member  114  when the rise restricted surface  114   c  of the releasing member  114  does not overlap with the rise restricting surface  110   e  of the cover  110 . The amount of rotation of the releasing member  114  in the rotational direction D in the first step suffices if the rise restricted surface  114   c  of the releasing member  114  does not overlap with the rise restricting surface  110   e  of the cover  110  as viewed in the direction of the rotational axis B. 
     The method of releasing the rotation restriction of the shutter  109  on the apparatus-side is a first step and a second step after the first step. The first step is a step of rotating the releasing member  114  from the rise restriction position to the rise restriction release position in the rotational direction D. The second step is a step of moving the releasing member upward together with the restricting member  113  so that the restricting member  113  moves from the restriction position to the restriction release position while the releasing member  114  is in the rise restriction release position. The second step may or may not include an operation of rotating the releasing member  114  in the rotational direction E until the contact surface  114   f  of the releasing member  114  abuts to the second contacted surface  110   b  of the cover  110 . 
     (Toner Pack) 
     Referring to  FIGS.  16  and  17   , the basic structure of the toner pack  100  will be described. Part (a) of  FIG.  16    is a front view of the toner pack  100  when the pack side shutter  103  is in the closed position. Part (b) of  FIG.  16    is a front view of the toner pack  100  when the pack side shutter  103  is in the open position.  FIG.  17    is an exploded perspective view of the toner pack  100 . 
     The toner pack  100  includes an accommodating portion  101  (first accommodating portion) for accommodating toner, a nozzle  102  (nozzle portion, pipe, tube, valve, discharging portion), and a pack-side shutter  103  (container shutter, rotatable member). As shown in  FIG.  16   , the accommodating portion  101  is provided on the side of the first end portion in the first direction D 1 , and the nozzle  102  and the pack side shutter  103  are provided on the side of the second end portion opposite from the first end portion in the first direction. The accommodating portion  101  is a pouch formed by pouch processing from a flexible polypropylene sheet. The accommodating portion  101  is not limited to the pouch, and may be a resin bottle or a container made of paper or vinyl resin material. 
     On the side surface  102   c  (first outer surface) of the nozzle  102  extending along the first direction D 1 , there is provided a discharge opening  102   a  (nozzle opening, first opening) structured to be in fluid communication with an inside of the accommodating portion  101 . The toner stored in the accommodating portion  101  is discharged to the outside of the toner pack  100  through the discharge opening  102   a . The nozzle  102  may be integrally structured with the accommodating portion  101 . In addition, a seal may be provided between the accommodating portion  101  and the discharge opening  102   a  of the nozzle  102 , so that the accommodating portion  101  and the discharge opening  102   a  may be brought into fluid communication with each other when the seal is removed. 
     A pack-side shutter  103  (rotatable member) is provided on the outside of the side surface  102   c  of the nozzle  102 . The pack-side shutter  103  is mounted so as to be rotatable around a rotational axis A (first rotational axis) extending in a direction along the first direction D 1 , and as shown in  FIG.  17   , it is provided with an opening  103   a  (rotatable member opening, first shutter). The pack-side shutter  103  is provided outside the side surface  102   c  in the radial direction r of the imaginary circle VC centered on the rotational axis A. The side surface  102   c  of the nozzle  102  is a curved surface which is convex toward the outside in the radial direction r of the imaginary circle VC centered on the rotational axis A. The inner surface of the pack-side shutter  103  (the surface facing the side surface  102   c ) is a curved surface along the side surface  102   c  of the nozzle  102 , and a substantially rectangular pack-side seal  105  is mounted thereto. The side surface  102   c  of the nozzle  102  is also a surface extending along the rotational axis A. 
     As shown in  FIG.  16   , the pack-side shutter  103  is structured to be rotatable around a rotational axis A between a closed position in which the pack-side seal  105  closes the discharge opening  102   a  of the nozzle  102  and an open position in which the discharge opening  102   a  is opened. When the pack-side shutter  103  is in the open position, the discharge opening  102   a  of the nozzle  102  is exposed through the opening  103   a.    
     Part (a) of  FIG.  16    and part (b) of  FIG.  16    show a state in which the pack-side shutter  103  is in the closed position and the open position, respectively. As shown in part (a) of  FIG.  16   , when the pack-side shutter  103  in the closed position is rotated in an arrow K direction (first rotational direction) about the rotational axis A, the pack side shutter  103  becomes in the open position shown in part (b) of  FIG.  16   . Conversely, when the pack-side shutter  103  is rotated from the open position in an arrow L direction (second rotational direction), it becomes in the closed position. In the rotational operation of the pack-side shutter  103 , the pack-side shutter  103  rubs against the side surface  102   c  of the nozzle  102  by way of the pack-side seal  105 . 
     Referring to  FIGS.  18  to  21   , the detailed structure of the nozzle  102  and the pack-side shutter  103  will be described. An arrow N indicates the direction from the accommodating portion  101  toward the nozzle  102 , and an arrow U direction is opposite thereto. The arrow N direction and the arrow U direction are parallel to the rotational axis A. 
     Part (a) of  FIG.  18    is an enlarged view of the neighborhood of the nozzle  102  when the pack-side shutter  103  is in the closed position. Part (b) of  FIG.  18    is a view of the toner pack  100  as viewed in the direction of arrow U in part (a) of  FIG.  18   . Part (a) of  FIG.  19    is an enlarged view of the neighborhood of the nozzle  102  when the pack-side shutter  103  is in the open position. Part (b) of  FIG.  19    is a side view of the toner pack  100  as viewed in the direction of arrow U in part (a) of  FIG.  19   .  FIG.  20    is a view of the neighborhood of the nozzle  102  as viewed from the side opposite to the side from which  FIG.  18    views.  FIG.  21    is a view of the neighborhood of the nozzle  102  as viewed in a direction parallel to the surfaces  102   d   1  and  102   d   2  of the nozzle  102  (direction perpendicular to the rotational axis A). 
     As shown in part (a) of  FIG.  18    and part (b) of  FIG.  18   , the nozzles  102  is provided with a positioned portion  102   d  having a surface  102   d   1  (first nozzle surface, first facing surface) and a surface  102   d   2  (second nozzle surface, second facing surface) which are arranged in an arrow R direction (second direction D 2 ) so as to face each other with a space therebetween and which extend in a direction perpendicular to the R direction. As shown in part (b) of  FIG.  18   , the surfaces  102   d   1  and  102   d   2  in this embodiment extend in a direction perpendicular to the arrow R direction and are parallel to each other. That is, the arrow R direction is a normal direction to the surfaces  102   d   1  and  102   d   2 . The positioned portion  102   d  engages with the positioning portion  107   a  (part (a) of  FIG.  3    of the first frame  107  when the toner pack  100  is mounted on the mounting portion  106 . By this, the position of the nozzle  102  in the direction of the arrow R relative to the first frame  107  (base frame  2 ) is determined. By this, the position of the nozzle  102  in the rotational direction about the rotational axis A relative to the first frame  107  is also determined. In part (b) of  FIG.  18   , a straight line CL 1  (first imaginary straight line) which passes through the center of the surface  102   d   1  and the surface  102   d   2  in the R direction and which extends in the direction perpendicular to the arrow R direction is in a phase rotated by about 90° relative to CL 2  (second imaginary straight line) which passes through the center of the rotational axis A and the discharge opening  102   a . That is, the straight line CL 1  and the straight line CL 2  are perpendicular to each other. 
     Further, as shown in  FIGS.  18  and  21   , the direction of the rotational axis A, the surface  102   d   1  and the surface  102   d   2  are provided with surfaces  102   e   1  and  102   e   2  on downstream sides in a N direction, respectively. As shown in part (b) of  FIG.  18   , the surfaces  102   e   1  and  102   e   2  extend in the radial direction r of the imaginary circle VC centered on the rotational axis A. 
     In  FIG.  21   , a side surface  102   e   3  (second outer surface) is provided between the surfaces  102   d   1  and  102   d   2  and between the surfaces  102   e   1  and  102   e   2  in the direction of arrow R. The side surface  102   e   3  is recessed inward in the radial direction r with respect to the side surface  102   c . The surface  102   d   1 , the surface  102   d   2 , the side surface  102   e   3 , the surface  102   e   1 , the surface  102   e   2  and the side surface  102   e   3  form a recess  102   e  (nozzle recess). 
     The surface  102   d   1  and the surface  102   d   2  do not necessarily have to be parallel as in this embodiment. The surface  102   d   1  and the surface  102   d   2  may extend in the radial direction r of the imaginary circle VC centered on the rotational axis A. 
     Further, as shown in  FIG.  18   , when viewed in a direction perpendicular to the direction of the rotational axis A (first direction D 1 ), the side surface  103   d  (the outer surface of the first rotation member) of the pack side shutter  103  is provided with an opening  103   a  (rotatable member opening). In part (a) of  FIG.  18   , when the pack-side shutter  103  is in the closed position, at least a part of the recess  102   e  of the nozzle  102  is exposed through the opening  103   a . By doing so, when the toner pack  100  is mounted on the mounting portion  106  with the pack-side shutter  103  closed, the recesses  102   e  (surfaces  102   d   1  and  102   d   2 ) are engaged with the positioning portion  107   a.    
     Further, as shown in part (b) of  FIG.  18   , as viewed in the direction of the rotational axis A (first direction D), when the pack side shutter  103  is in the closed position a driven transmission portion  103   e  (rotatable member recess) is provided on the opposite side across the rotational axis A from the recess  102   e  of the nozzle  102  (opening  103   a  of the pack-side shutter  103 ). Both the surface  103   b   1  and the surface  103   b   2  of the driven transmission portion  103   e  extend in a direction perpendicular to the arrow R direction.  FIG.  20    is an enlarged perspective view of the neighborhood of the pack-side shutter  103  as viewed from the side where the driven transmission portion  103   e  is provided. Between the surfaces  103   b   1  and  103   b   2 , there is a side surface  103   b   3  (outer surface of the second rotatable member) recessed inward in the radial direction r beyond the side surface  103   d . The driven transmission portion  103   e  comprises the surface  103   b   1 , the surface  103   b   2 , and the side surface  103   b   3 . 
     When the pack-side shutter  103  is rotated in the arrow K direction from the closed position shown in  FIG.  18   , the pack-side shutter  103  takes an open position, and the discharge opening  102   a  of the nozzle  102  is exposed through the opening  103   a  of the pack-side shutter  103  as shown in  FIG.  19   . 
     Further, as shown in  FIGS.  18  and  20   , the pack-side shutter  103  is provided with a radial positioning portion  103   f  projecting outward in the radial direction r beyond the side surface  103   d . The radial positioning portion  103   f  is provided on the upstream side of the pack side shutter  103  in the N direction of the direction of the rotational axis A. The radial positioning portion  103   f  is provided at each of three locations at intervals in the rotational direction of the pack-side shutter  103  (circumferential direction of the imaginary circle VC). The structure is such that when the toner pack  100  is mounted on the mounting portion  106 , the radial positioning portion  103   f  of the pack-side shutter  10  abuts on the inner peripheral surface  109   h  of the apparatus-side shutter  109  so that the position of the toner pack  100  in the radial direction r is determined. 
     The nozzle  102  in this embodiment is a component provided with a passage through which the toner passes and a discharge opening  102   a  for discharging the toner through the nozzle  102 . A cross-sectional area of the passage of the nozzle  102  through which the toner passes may be smaller, larger, or even as goes toward the discharge opening  102   a . The cross-sectional area and length of the passage of the nozzle  102  may be appropriately changed depending on the toner discharging property and the like, and therefore, they are not limited. In addition, the discharge opening  102   a  of the nozzle  102  does not have to be the most downstream opening from which the toner is discharged from the toner pack  100 . The toner discharged from the discharge opening  102   a  of the nozzle  102  may be discharged to the outside of the toner pack  100  after passing through a passage of a member different from the nozzle  102 . 
     The pack-side shutter  103  may be a rotatable member including a driven transmission portion  103   e  and always opening the discharge opening  102   a  of the nozzle  102  regardless of the rotation position. In such a case, the structure may be such that the discharge opening  102   a  of the nozzle  102  is closed by a seal when the toner pack  100  is not mounted to the mounting portion  106 , and the seal is removed by the mounting operation to the mounting portion  106  or after the mounting of the toner pack  100 . Furthermore, the toner pack  100  may not be provided with a pack side shutter  103 . 
     (Restriction Releasing Portion of Toner Pack) 
     Referring to  FIGS.  16  to  21   , the restriction releasing portion  104  will be described. As shown in  FIG.  16   , the toner pack  100  is oriented so that the side of the second end portion (the side of the nozzle  102 ) of the toner pack  100  is below the side of the first end portion (the side of the toner accommodating portion). Or, the toner pack  100  is oriented so that at least a part of the nozzle  102  is below the accommodating portion  101  and the rotational axis A is in the vertical direction. This attitude is an attitude for mounting on the mounting portion  106  of the image forming apparatus  1 . At this time, in part (a) of  FIG.  18    and part (a) of  FIG.  19   , the arrow N direction is downward and the arrow U direction is upward. 
     The nozzle  102  is provided with a projecting portion  102   b  (projecting portion, engaging portion) which projects (projects) in the arrow N direction (downward) beyond the end surface  103   c  of the pack side shutter  103  in the arrow N direction. As shown in part (a) of  FIG.  18   , the projecting portion  102   b  is a cylindrical portion (a portion including a cylindrical shape) centered on the rotational axis A. The projecting portion  102   b  has a projecting portion end surface  102   b   2  which is a lower end surface. The projecting portion end surface  102   b   2  is provided with a hole defined by an inner peripheral surface  102   b   1  (inner peripheral guide surface) centered on the rotational axis A. The projecting portion  102   b  projects downward beyond the end surface  103   c  of the pack-side shutter  103  provided below the discharge opening  102   a . Further, as shown in  FIG.  17   , the projecting portion  102   b  projects downward beyond a lower end surface  102   j  of the nozzle  102 . In this embodiment, the end surface  103   c  of the pack-side shutter  103  and the end surface  102   j  of the nozzle  102  are end surfaces perpendicular to the rotational axis A, but are not limited to such a structure. These surfaces may be any surface extending in a direction crossing the rotational axis A as viewed in a direction perpendicular to the rotational axis A. 
     The outer peripheral surface  102   b   3  of the projecting portion  102   b  is provided with a restriction releasing portion  104  including a first restriction releasing portion  104   a  (first projection) and a second restriction releasing portion  104   b  (second projection). The first restriction releasing portion  104   a  and the second restriction releasing portion  104   b  have a symmetric shape with respect to the rotational axis A. That is, as shown in  FIG.  20   , the second restriction releasing portion  104   b  is on the opposite side of the first restriction releasing portion  104   a  with respect to the rotational axis A in the direction perpendicular to the rotational axis A. In other words, the second restriction releasing portion  104   b  has a shape which is rotationally 180-degree symmetric with respect to the rotational axis A of the first restriction releasing portion  104   a.    
     The first restriction releasing portion  104   a  includes a first slope  104   a   1  (first engaging surface, downward surface, downward guide surface, downward force applying surface, downward push surface) and a second slope  104   a   2  (second engaging surface upward surface, upward guide surface). The first slope  104   a   1  is below the second slope  104   a   2  and overlaps with the second slope  104   a   2  as viewed in the direction of the rotational axis A. As shown in part (a) of  FIG.  18   , the first slope  104   a   1  is a surface which extends so as to go in the arrow U direction (upward) as goes in the rotational direction K (predetermined rotational direction, first rotational direction, first circumferential direction of the imaginary circle VC) about the rotational axis A and which faces in the arrow N direction (downward). 
     On the other hand, the second slope  104   a   2  is a surface extending so as to go in the arrow N direction (downward) as goes in the rotational direction K about the rotational axis A, and is a surface facing the arrow U direction (upward). In other words, the second slope  104   a   2  is a surface extending so as to go in the arrow U direction as goes in the rotational direction L (second rotational direction, the second circumferential direction of the imaginary circle VC) about the rotational axis A and facing in the arrow U direction. A cavity  104   a   3  is provided above (directly above) the second slope  104   a   2 . 
     The downstream end of the first slope  104   a   1  and the downstream end of the second slope  104   a   2  in the rotational direction K are continuous with each other. That is, the downstream end of the first slope  104   a   1  and the downstream end of the second slope  104   a   2  in the rotational direction K are at the same position in the rotational direction D. In other words, the downstream end of the first slope  104   a   1  and the downstream end of the second slope  104   a   2  are in overlapping positions as viewed in the direction of the rotational axis A. 
     In other words, there is a connecting portion which connects the downstream end of the first slope  104   a   1  in the rotational direction K and an upstream end of the second slope  104   a   2  in the rotational direction L. 
     As shown in  FIG.  21   , as viewed in a direction perpendicular to the rotational axis A (first direction D 1 ), the first slope  104   a   1  extends so as to go up (arrow U direction) as goes in an arrow J direction (predetermined direction) perpendicular to the rotational axis A. The second slope  104   a   2  extends so as to go down (arrow N direction) as goes in the direction of arrow J (predetermined direction) perpendicular to the axis of rotation A. 
     The ridge line  104   a   5  of the first slope  104   a   1  also extends such that it goes in the direction of the arrow U as goes in the direction of the arrow J perpendicular to the rotational axis A. The ridge line  104   a   4  of the second slope  104   a   2  also extends such that it goes in the direction of the arrow N as goes in the direction of the arrow J perpendicular to the rotational axis A. The ridge line described here is a boundary line between surfaces. The ridge line  104   a   5  is a boundary line between the first slope  104   a   1  and the outer peripheral surface of the first restriction releasing portion  104   a . The ridge line  104   a   4  is a boundary line between the second slope  104   a   2  and the outer peripheral surface of the first restriction releasing portion  104   a.    
     As shown in  FIG.  20   , the second restriction releasing portion  104   b  has a first slope  104   b   1  (downward surface) and a second slope  104   b   2  (upward surface). A cavity  104   b   3  is provided above the second slope  104   b   2 . The first slope  104   b   1 , the second slope  104   b   2 , and the cavity  104   b   3  have the same structures as the first slope  104   a   1 , the second slope  104   a   2 , and the cavity  104   a   3  of the first restriction releasing portion  104   a , respectively, and therefore, the description thereof will be omitted. 
       FIG.  22    is a cross-sectional view of the projecting portion  102   b  taken along a line X 33 -X 33  in  FIG.  21   .  FIG.  22    shows the second slope  104   a   2  of the first restriction releasing portion  104   a  and the second slope  104   b   2  of the second restriction releasing portion  104   b  as viewed from above. In  FIG.  22   , it is understood that both the second slope  104   a   2  and the second slope  104   b   2  extend along the rotational direction of the pack-side shutter  103  (the circumferential direction of the imaginary circle VC centered on the rotational axis A). 
     Further, as shown in  FIG.  21   , the arrow J direction is parallel to the arrow R direction (second direction) which is the normal direction of the surface  102   d   1  and the surface  102   d   2 . And, in part (b) of  FIG.  18   , a straight line Q passing through the first restriction releasing portion  104   a  and the second restriction releasing portion  104   b  extends in the direction crossing the arrow R direction. 
     As shown in  FIG.  21   , in the direction of arrow R, the positions of the first restriction releasing portion  104   a  and the second restriction releasing portion  104   b  are between the position of the surface  102   d   1  and the position of the surface  102   d   2  of the positioned portion  102   d . That is, as viewed in the direction perpendicular to the rotational axis A (arrow R direction), the positions of the first slope  104   a   1  and the second slope  104   a   2  are both between the position of the surface  102   d   1  and the position of the surface  102   d   2  in the direction of the arrow R. Viewed in the direction perpendicular to the rotational axis A (arrow R direction), the positions of the first restriction releasing portion  104   a  and the second restriction releasing portion  104   b  overlap with the positions of the recess  102   e  in the arrow R direction. 
     It is desirable that the inclination angles of the first slope  104   a   1  and the second slope  104   a   2  with respect to the rotational axis A are in the range of 45° 15°. In addition, in this embodiment, a length of the first slope  104   a   1  in the direction of the rotational axis A is about 2 mm, a length of the second slope  104   a   2  is about 3 mm, and a length of the second slope  104   a   2  is larger than that of the first slope  104   a   1 . 
     The first slope  104   a   1 , the second slope  104   a   2 , and the cavity  104   a   3  are exposed to the outside of the toner pack  100  so that the rotation restricting mechanism  112  of the mounting portion  106  can be accessed. Further, the projecting portion  102   b  does not necessarily have to be provided on the nozzle  102 . 
     (Mounting Toner Pack to Mounting Portion) 
     Referring to  FIGS.  23  to  29   , a mechanism for releasing the rotation restriction of the apparatus-side shutter  109  by the rotation restricting mechanism  112  described in the foregoing by mounting the toner pack  100  on the mounting portion  106  will be described. 
     Part (a) of  FIG.  23    is a perspective view of the toner pack  100  and the mounting portion  106  while the toner pack  100  is being mounted on the mounting portion  106 . Part (b) of  FIG.  23    is a perspective view of the toner pack  100  and the mounting portion  106  as viewed from a point different from that in part (a) of  FIG.  23   .  FIG.  24    is a sectional view taken along a line parallel to the rotational axis A (rotational axis B) in a state in which the toner pack  100  is further moved from the state of  FIG.  23    in the mounting direction. Part (a) of  FIG.  25    is a cross-sectional view taken along a line X 4 -X 4  in  FIG.  24   . Part (b) of  FIG.  25    is a cross-sectional view taken along a line X 5 -X 5  in  FIG.  24   . Part (a) of  FIG.  26    is a sectional view taken along a line X 6 -X 6  in  FIG.  24   . Part (a) of  FIGS.  26  to  26    ( d ) are sectional views illustrating a process of mounting the toner pack  100  on the mounting portion  106 . Part (a) of  FIG.  27    is a sectional view taken along a line X 7 -X 7  in part (d) of  FIG.  26   . Part (b) of  FIG.  27    is a cross-sectional view taken along a line X 8 -X 8  in part (a) of  FIG.  27   . 
     In  FIG.  24   ,  FIG.  25   , and part (b) of  FIG.  27   , the cut surfaces of the pack-side shutter  103  and the cover  110  are shaded for better illustration. Further, in  FIG.  26   , the pack side shutter  103 , the restricting member  113 , and the releasing member  114  are shown in side views, and the members other than them are shown in sectional views. Further, in  FIG.  27   , the cut surfaces of the cover  110 , the restricting member  113 , and the releasing member  114  are shaded for better illustration. 
     As shown in  FIG.  23   , the toner pack  100  with the pack-side shutter  103  in the closed position is moved in the mounting direction M relative to the mounting portion  106  with the apparatus-side shutter  109  in the closed position. At this time, as viewed in the mounting direction M the pack-side shutter  103  is positioned in the rotational direction, to effect alignment between the positions of the recess  102   e  of the nozzle  102  (opening  103   a  of the pack-side shutter  103 ) and the positioning portion  107   a  of the first frame  107 . At the same time, the pack-side shutter  103  is positioned in the rotational direction, to effect alignment between the positions of the driven transmission portion  103   e  of the pack-side shutter  103  and the drive transmission portion  108   a  of the operating lever  108  in the rotational direction of the pack-side shutter  103 . 
     After the positioning described above, the toner pack  100  is moved in the mounting direction M and mounted on the mounting portion  106 , then, as shown in  FIG.  24   , the inner peripheral surface  102   b   1  of the projecting portion  102   b  of the nozzle  102  is fitted (engaged) around a small diameter portion  109   d   2  of the center boss  109   d  of the apparatus-side shutter  109 . By this, the position of the nozzle  102  in the radial direction relative to the apparatus-side shutter  109  below the nozzle  102  (downstream side in the mounting direction M) is determined. The inner peripheral surface  102   b   1  of the projecting portion  102   b  does not necessarily have to be structured to fit with the center boss  109   d , and may be structured so as not to interfere with the center boss  109   d . As shown in part (a) of  FIG.  25   , the drive transmission portion  108   a  (lever projection) of the operating lever  108  and the driven transmission portion  103   e  (rotatable member recess portion) of the pack side shutter  103  engage with each other. At the same time, as shown in part (b) of  FIG.  25   , the side surface  110   f  and the side surface  110   g  of the cover  110  become close to the surfaces  102   e   1  and  102   e   2  forming the recess  102   e  (nozzle recess) of the nozzle  102 , respectively. Further, the driven transmission portion  103   e  (rotatable member recess portion) of the pack-side shutter  103  engages with the driven transmission portion  109   e  (shutter projection) of the apparatus-side shutter  109 . By this, the rotational axis A of the pack-side shutter  103  and the rotational axis B of the apparatus-side shutter  109  become substantially coaxial. The operating lever  108 , the pack-side shutter  103 , and the apparatus-side shutter  109  are substantially integrally rotatable relative to the first frame  107  (base frame  2 ) and the nozzle  102  in the rotation about the rotational axis A (rotational axis B). Specifically, when the operating lever  108  is rotated, the drive transmission portion  108   a  of the operating lever  108  presses the surface  103   b   1  or  103   b   2  of the pack side shutter  103 , so that the pack side shutter  103  is rotated. Thereafter, the surface  103   b   1  or the surface  103   b   2  of the pack-side shutter  103  presses the driven transmission portion  109   e  of the apparatus-side shutter  109  to rotate the apparatus-side shutter  109 . 
     Here, if the apparatus-side shutter  109  rotates from the closed position to the open position due to vibration during transportation of the image forming apparatus  1 , the position of the driven transmission portion  109   e  of the apparatus-side shutter  109  deviates in the rotational direction. Then, when the toner pack  100  is to be mounted on the mounting portion  106 , what happens is as follows. When the driven transmission portion  103   e  of the pack-side shutter  103  engages with the drive transmission portion  108   a  of the operating lever  108 , and thereafter the toner pack  100  is further moved in the mounting direction M, it cannot engage with the driven transmission portion  109   e  of the apparatus-side shutter  109 . Therefore, the toner pack  100  cannot be moved to the mounting complete position relative to the mounting portion  106 . In order to prevent such a situation from occurring, a rotation restricting mechanism  112  of the shutter  109  on the apparatus-side is provided. 
     Here, a mechanism will be described in which the rotation restricting mechanism  112  of the mounting portion  106  is released by mounting the toner pack  100  to the mounting portion  106 . Hereinafter, the second restriction releasing portion  104   b  functions in the same manner as the first restriction releasing portion  104   a , and therefore, the description thereof will be omitted. 
     At the time of the state of part (a) of  FIG.  26   , the first restriction releasing portion  104   a  of the nozzle  102  and the releasing claw  114   e  of the releasing member  114  are not yet in contact with each other. When the toner pack  100  is further moved in the arrow N direction (mounting direction M) from this position, as shown in part (b) of  FIG.  26   , the first slope  104   a   1  of the first restriction releasing portion  104   a  and the releasing claw  114   e  are brought into contact with each other. When the toner pack  100  is further moved in the direction of arrow N from this position, the releasing member  114  is rotated in the rotational direction D by a force F 5  received by the releasing claw  114   e  from the first slope  104   a   1  against the moment M 2  (urging force) applied by the release spring  116 . At this time, the first slope  104   a   1  guides the releasing claw  114   e  so that the releasing member  114  is rotated in the rotational direction D. The releasing member  114  rotates in the rotational direction D until the releasing claw  114   e  passes the downstream end of the first slope  104   a   1  in the rotational direction D. The rotation of the releasing member  114  in the rotational direction D is the first step described above. That is, as shown in part (a) of  FIG.  15   , this is a step in which the rise restricted surface  114   c  of the restriction member lifted causes the releasing member  114  to rotate in the rotational direction D against the urging force of the release spring  116  until the it reaches a position where it does not contact the rise restricting surface  110   e  of the cover  110 . 
     After the first step, the releasing claw  114   e  rides on the downstream end of the second slope  104   a   2  in the rotational direction D. In other words, after the first step, the releasing claw  114   e  rides on the upstream end of the second slope  104   a   2  in the rotational direction E. At this time, as shown in part (c) of  FIG.  26   , the releasing claw  114   e  is contacted by the second slope  104   a   2  of the nozzle  102  by the moment M 2  (urging force) provided by the release spring  116  to receive a force F 6 . Then, by the arrow G direction component F 6   a  of the force F 6 , the releasing member  114  is moved (guided) in the arrow G direction (upward) along the second slope  104   a   2  and at the same time rotates in the rotational direction E about the rotational axis A. That is, the rotational direction of the releasing member  114  changes from the rotational direction D to the direction E at the connecting portion where the downstream end of the first slope  104   a   1  in the rotational direction D and the upstream end of the second slope  104   a   2  in the rotational direction E are connected. In addition, the second slope  104   a   2  guides the releasing claw  114   e  so that the releasing member  114  is moved upward. The second slope  104   a   2  guides the releasing claw  114   e  so that the releasing member  114  is moved upward while being rotated in the rotational direction E. 
     The movement of the releasing member  114  in the arrow G direction (upward) and the rotation in the rotational direction E are the second steps described in the foregoing. Here, as described above, in the second step, the restricting member  113  moves in the arrow G direction together with the releasing member  114 . As shown in part (a) of  FIG.  15   , at least one of the contact surfaces  114   f  (pair) of the releasing member  114  is rotationally moved until it comes into contact with one of the second contact surfaces  110   b  of the corresponding cover  110 , thus reaching the mounting completion position shown in part (d) of  FIG.  26    and  FIG.  27   . As shown in part (d) of  FIG.  26   , when the contact surface  114   f  of the releasing member abuts to the second contact surface  110   b  of the cover  110 , a part of the releasing claw  114   e  enters the cavity  104   a   3  above (directly above) the second slope  104   a   2 . 
     As described above, by mounting the toner pack  100  on the mounting portion  106 , the rotation restriction by the rotation restricting mechanism  112  of the apparatus-side shutter  109  is released through the first step and the second step described above. 
     When the toner pack  100  is in the mounting complete position, as shown in  FIG.  27   , the projecting portion end surface  102   b   2  of the projecting portion  102   b  of the nozzle  102  is in contact with the pack contact surface  109   g  of the apparatus-side shutter  109 . By this, the position of the nozzle  102  (toner pack  100 ) in the direction of the rotational axis A (mounting direction M) is determined with respect to the mounting portion  106 . In addition, three points of the radial positioning portion  103   f  ( FIGS.  18  and  20   ) of the pack side shutter  103  are in contact with the inner peripheral surface  109   h  ( FIG.  7   ) of the apparatus-side shutter  109 . By this, the positions of the nozzle  102  and the pack-side shutter  103  (toner pack  100 ) in the radial direction on the upstream side in the mounting direction M are determined. 
     The sectional view of X 10 -X 10  in part (a) of  FIG.  27    is the same as that in part (a) of  FIG.  15   , and therefore, the description thereof will be omitted. As shown in part (b) of  FIG.  27   , which is a cross-section of X 8 -X 8  in part (a) of  FIG.  27   , the positioning portion  107   a  of the first frame  107  is engaged with the positioned portion  102   d  of the nozzle  102  having the surfaces  102   d   1  and  102   d   2 . Therefore, the nozzle  102  is positioned relative to the first frame  107  (base frame  2 ) in the arrow R direction of the surfaces  102   d   1  and  102   d   2 . As shown in  FIG.  26   , the arrow R direction is substantially parallel to the locus V in which the releasing claw  114   e  rotates in the rotational direction D when the first restriction releasing portion  104   a  and the releasing claw  114   e  come into contact with each other. By this, the position of the nozzle  102  is determined relative to the first frame  107  in the direction of the arrow R, And therefore, the operation of releasing the rotation restriction relative to the apparatus-side shutter  109  can be further stabilized. 
     By the mechanism described above, the rotation restriction by the rotation restricting mechanism  112  of the apparatus-side shutter  109  is released, and the apparatus-side shutter  109  is enabled to rotate from the closed position to the release position. When the pair of contact surfaces  114   f  abut on the pair of second contact surfaces  110   b , the releasing member  114  is vigorously rotated by the moment M 2 , so that a light collision sound is produced and at the same time, the user&#39;s hand holding the toner pack  100  feels the reaction. That is, the user can recognize that the locking of the shutter  109  on the apparatus-side has been released by the collision sound and the reaction. When the toner pack  100  is dismounted from the mounting portion  106 , the reverse process of  FIG.  26    is carried out, and the apparatus-side shutter  109  is again restricted by the rotation restricting mechanism  112 . 
     (Lever Operation) 
     As described above, In the state in the toner pack  100  is mounted on the mounting portion  106 , the operating lever  108 , the pack side shutter  103 , and the apparatus-side shutter  109  rotate integrally about the rotational axis A (rotational axis B). 
     Here, part (a) of  FIG.  28    is a perspective view of the toner pack  100  at the time when the operating lever  108  is in the closed position, as viewed from above. Part (b) of  FIG.  28    is a perspective view of the toner pack  100  at the time when the operating lever  108  is in the open position, as viewed from above. 
     As shown in  FIG.  28   , when the operating portion  108   b  of the operating lever  108  is rotated in the rotational direction D after the mounting of the toner pack  100  to the mounting portion  106  is completed, the shutter  109  on the apparatus-side is rotated from the closed position to the open position, and the pack side shutter  103  rotates from the closed position to the open position. 
     When the pack-side shutter  103  rotates from the closed position to the open position, the frictional force F 7  received by the nozzle  102  from the pack-side shutter  103  by way of the pack-side seal  105  is directed in the arrow K direction as shown in part (a) of  FIG.  18   . This is the same direction as the rotational direction D of the operating lever  108  in  FIG.  28   . The nozzle  102  receives the frictional force F 7  and rotates between the surfaces  102   d   1  and  102   d   2 , and the positioning portion  107   a  of the first frame  107 , by the amount of the engagement play (play) in the arrow K direction, the rotational direction of the nozzle  102  at this time is such that the second slope  104   a   2  of the first restriction releasing portion  104   a  approaches the releasing claw  114   e  of the releasing member  114 , and such that the second slope  104   b   2  of the second restriction releasing portion  104   b  approaches the releasing member  114 . That is, when the operating lever  108  is rotated to rotate the pack-side shutter  103  from the closed position to the open position, the restricting member  113  moves upward (in the direction opposite to the mounting direction M) together with the releasing member  114 . Then, the second restricted surface  113   c  of the restricting member  113  is separated upward from the restricted rib  109   c  of the apparatus-side shutter  109 , and the margin for releasing the rotation restriction is increased. Therefore, it is possible to more stably maintain the state in which the rotation restriction for the apparatus-side shutter  109  is released. 
     By the above-described operation, the toner pack  100  accommodating portion  101  and the toner accommodating chamber  36  are rotated in fluid communication with each other through the discharge opening  102   a , the receiving opening  109   a , and the apparatus-side opening  117   a.    
     Here, part (a) of  FIG.  29    is a sectional view of the toner pack  100  and the mounting portion  106  when both the apparatus-side shutter  109  and the pack-side shutter  103  are in the respective closed positions. Part (b) of  FIG.  29    is a sectional view of the toner pack  100  and the mounting portion  106  when both the apparatus-side shutter  109  and the pack-side shutter  103  are in the respective open positions. 
     In part (a) of  FIG.  29   , the discharge opening  102   a  of the nozzle  102  is closed by the pack side shutter  103 , the pack side seal  105 , and by the apparatus-side shutter  109 , and the toner in the accommodating portion  101  cannot reach the apparatus-side opening  117   a  of the second frame  117 . On the other hand, in part (b) of  FIG.  29   , the discharge opening  102   a  of the nozzle  102  is opened by moving the pack-side shutter  103 , the pack-side seal  105 , and the apparatus-side shutter  109 . Therefore, the toner in the accommodating portion  101  is compressed by the user compressing the accommodating portion  101 , the toner in the accommodating portion  101  reaches the apparatus-side opening  117   a  of the second frame  117  together with the air through the discharge opening  102   a , and the toner is supplied into the toner accommodating chamber  36  of the developer container  32  through the side opening  117   a.    
     Modified Example 1 
     In this embodiment, the first restriction releasing portion  104   a  and the second restriction releasing portion  104   b  are provided on the outer peripheral surface  102   b   3  of the projecting portion  102   b  of the nozzle  102 . However, the following structure may be employed instead. 
     First, as shown in part (a) of  FIG.  30   , a projecting portion  1020   b  is provided with a restriction releasing portion  1040   a  corresponding to the first restriction releasing portion  104   a  of Embodiment 1. However, there is not provided a portion corresponding to the second restriction releasing portion  104   b.    
     Second, as shown in part (b) of  FIG.  30   , the projecting portion  1021   b  is provided with a restriction releasing portion  1040   b  corresponding to the second restriction releasing portion  104   b  of Embodiment 1. However, there is not provided a portion corresponding to the first restriction releasing portion  104   a.    
     Modified Example 2 
     In this embodiment, the first restriction releasing portion  104   a  is provided with the first slope  104   a   1  and the second slope  104   a   2 , and the second restriction releasing portion  104   b  has a sheet which is rotationally symmetric with the first restriction releasing portion  104   a  about the rotational axis A. However, the following structure may be used instead. 
     First, as shown in part (a) of  FIG.  31   , although the first restriction releasing portion  1041   a  is provided with a second slope  1014   a   2  corresponding to the second slope  104   a   2  of Embodiment 1, it does not have a slope corresponding to the first slope  104   a   1  of Embodiment 1. Further, although the second restriction releasing portion  1041   b  has a first slope  1041   b   1  corresponding to the first slope  104   a   1  of Embodiment 1, it does not have a slope corresponding to the second slope  104   a   2  of Embodiment 1. 
     Second, as shown in part (b) of  FIG.  31   , although the first restriction releasing portion  1042   a  has a first slope  1042   a   1  of Embodiment 1, It does not have a slope corresponding to the second slope  104   a   2  of Embodiment 1. Further, although the second restriction releasing portion  1042   b  has a second slope  1042   b   2  corresponding to the second slope  104   a   2  of Embodiment 1, it does not have a slope corresponding to the first slope  104   a   1  of Embodiment 1. 
     Modified Example 3 
     In this embodiment, the projecting portion  102   b  is provided with the first restriction releasing portion  104   a  and the second restriction releasing portion  104   b  on the outer peripheral surface  102   b   3  of the cylindrical portion having the hole with the inner peripheral surface  102   b   1  on the projecting portion end surface  102   b   2 . However, the following structure may be employed instead. 
     As shown in  FIG.  32   , it has a projecting portion  1023   b  including no wall surface (wall surface corresponding to the outer peripheral surface  102   b   3 ) connecting between a first restriction releasing portion  1043   a  and a second restriction releasing portion  1043   b . The first restriction releasing portion  1043   a  is a first projection including a first slope  1043   a   1  and a second slope  1043   a   2  corresponding to the first slope  104   a   1  and the second slope  104   a   2  of Embodiment 1, respectively, and is a first projection projecting downward. The second restriction releasing portion  1043   b  has a first slope  1043   b   1  and a second slope  1043   b   2  corresponding to the first slope  104   b   1  and the second slope  104   b   2  of Embodiment 1, respectively, and is a second projection projecting downward. There is provided a space between the first restriction releasing portion  1043   a  and the second restriction releasing portion  1043   b.    
     Modified Example 4 
     As shown in part (a) of  FIG.  33   , two round shaft-shaped bosses may be used as the first restriction releasing portion  1044   a  and the second restriction releasing portion  1044   b , respectively. As viewed in the axial direction of the first restriction releasing portion  1044   a , as shown in part (b) of  FIG.  33   , a Y axis extending in the direction of the rotational axis A (arrow U direction) and an X-axis extending in the direction perpendicular to the rotational axis A are defined with the axis of the first restriction releasing portion  1044   a  as an origin. Of the four quadrants separated by the X-axis and the Y-axis, the outer peripheral surface of the first restriction releasing portion  1044   a  in the fourth quadrant is the first slope  1044   a   1 , and the outer peripheral surface of the first restriction releasing portion  1044   a  in the first quadrant is the second slope  1044   a   2 . The same applies to the second restriction releasing portion  1044   b . Therefore, the same effects as those of this embodiment can be provided. 
     Modified Example 5 
     As shown in part (a) of  FIG.  34   , the toner pack  1050  in which the nozzle  1025  is bent into an L shape may be used. The accommodating portion  1015  has a structure extending in a direction intersecting the rotational axis A of the pack-side shutter  1035 . 
     Further, as shown in part (b) of  FIG.  34   , the toner pack  1052  in which the accommodating portion  10151  of the toner pack  1051  hangs down may be used. 
     Modified Example 6 
     In this embodiment, the first restriction releasing portion  104   a  and the second restriction releasing portion  104   b  are fixed to the nozzle  102 , but they may be movable. In this modified example, as shown in part (a) of  FIG.  35   , The structure is such that when the toner pack  1060  is not mounted on the mounting portion  106  of the image forming apparatus  1 , the first restriction releasing portion  1046   a  is accommodated inside (inner peripheral surface  1026   b   1  side) the outer peripheral surface  1026   b   3  of the projecting portion  1026   b . And, The structure is such that in the process of mounting the toner pack  1060  on the mounting portion  106  of the image forming apparatus  1  or by the user&#39;s operation, the first restriction releasing portion  1046   a  projects to the outside of the imaginary circle VC of the outer peripheral surface  1026   b   3  of the projecting portion  1026   b  in the radial direction r. 
     As an example of the structure in which the first restriction releasing portion  1046   a  projects outward in the radial direction r in the process of mounting the toner pack  1060  on the mounting portion  106  of the image forming apparatus  1 , when the center boss  109   d  of the apparatus-side shutter  109  is inserted inside the inner peripheral surface  1026   b   1  of the projecting portion  1026   b , the first restriction releasing portion  1046   a  is pushed by the center boss  109   d  to project outward beyond the outer peripheral surface  1026   b   3  in the radial direction. The same structure as that of the first restriction releasing portion  1046   a  can be applied to the second restriction releasing portion  1046   b.    
     Modified Example 7 
     The structure may be such that when the toner pack  1070  is not mounted to the image forming apparatus  1 , the projecting portion  1027   b  does not project from the end surface  1037   c  of the pack side shutter  1037 , and the projecting portion  1027   b  project in the direction of the arrow N beyond the end surface  1037   c  in the process of mounting the toner pack to the image forming apparatus  1 . That is, the projecting portion  1027   b  may be movable so as to take a projected position (projection position) as shown in part (b) of  FIG.  36    in which it projects (projects) in the arrow N direction beyond the end surface  1037   c  and the retracted position as shown in part (a) of  FIG.  36    in which it is retracted in the U direction from the projecting position ( FIG.  36   ). The projecting portion  1027   b  may be structured not to project from the end surface  1037   c  in the retracted position. In such a case, user may manually move the projecting portion  1027   b  to the projection position and to the retracted position. 
     Modified Example 8 
     As shown in part (a) of  FIG.  37   , in a state in which the toner pack  1080  is not mounted to the image forming apparatus  1 , the first restriction releasing portion  1048   a  is a linear rib extending in the direction of the rotational axis A and has only a surface extending in the direction of the axis A. The first restriction releasing portion  1048   a  has a rotation center  1048   a   3  at a position between one end and the other end in the direction of the rotational axis A. The structure may be such that during or before the process of mounting on the mounting portion  106  of the image forming apparatus  1 , the rib is moved (rotated) by the user about the rotation center  1048   a   3  so as to provide a first slope  1048   a   1  corresponding to the first slope  104   a   1  of Embodiment 1 and a second slope  1048   a   2  corresponding to the second slope  104   a   2  of Embodiment 1, as shown in part (b) of  FIG.  37   . 
     Modified Example 9 
     In this embodiment, the nozzle  102  and the projecting portion  102   b  are integral with each other, but these may be separate members. That is, as shown in  FIG.  38   , it may be a mounting kit including a toner pack  1090  accommodating the toner and an attachment  1090   b , and may be a mounting kit for mounting to image forming mounting. 
     The toner pack  1090  has the same structure as that of Embodiment 1 except that the portion corresponding to the projecting portion  102   b  of Embodiment 1 is not provided, and therefore, the description thereof will be omitted. 
     The attachment  1090   b  has a cylindrical shape having an outer peripheral surface  1029   a   3  centered on the central axis Z. The attachment  1090   b  is provided with a first restriction releasing portion  1049   a  and a second restriction releasing portion  1049   b  on the outer peripheral surface  1029   a   3  when the central axis Z is oriented in the vertical direction (gravity direction). The first restriction releasing portion  1049   a  has an upward facing surface  1049   a   2  which faces upward and goes downward as goes in the circumferential direction of the outer peripheral surface  1029   a   3  (the first circumferential direction KZ of the imaginary circle VCZ centered on the central axis Z). In other words, the upward surface  1049   a   2  is configured to extend so as to go up as goes in the second circumferential direction LZ, which is the opposite direction of the first circumferential direction KZ of the imaginary circle VCZ and to face upward  61806180 . The attachment  1090   b  also has a downward surface  1049   a   1  structured to face downward and to extend so as to go up as goes in the circumferential direction (first circumferential direction KZ) of the outer peripheral surface  1029   b   3 . Further, it has a connecting portion  1049   a   23  which connects the upstream end of the upward surface  1049   a   2  in the second circumferential direction LZ and the downstream end of the downward surface  1049   a   1  in the first circumferential direction KZ. 
     The attachment  1090   b  may be structured to be mountable to the bottom surface of the nozzle  1029  of the toner pack  1090  (bottom surface of the toner pack  1090 ). Further, the attachment  1090   b  may be structured not to be mounted to the toner pack  1090 . That is, the attachment  1090   b  is first mounted to the mounting portion  106  of the image forming apparatus  1 , so that the rotation restriction of the shutter  109  on the apparatus side is released. Then, after mounting the attachment  1090   b , the toner pack  1090  is mounted on the mounting portion  106 . The mechanism by which the rotation restriction of the apparatus-side shutter  109  by the rotation restricting mechanism  112  is released by mounting the attachment  1090   b  to the mounting portion  106  is the same as the case in which the toner pack  100  is mounted on the mounting portion  106 , and therefore, the explanation therefor is omitted. 
     Finally, a minute uneven surface formed by finely and alternately repeating a surface parallel to or perpendicular to the rotational axis A as shown in  FIG.  39    will be described. In the case that an envelope S of the uneven surface extends in the same direction as the second slope  104   a   2  of the base embodiment or any of the modified examples, it can be regarded as the first slope  104   a   1  or the second slope  104   a   2  of Embodiment 1. The same applies to Embodiment 2 and the modified examples of Embodiment 2 described below. 
     Embodiment 2 
     Referring to  FIGS.  40  to  71   , the structure of Embodiment 2 will be described. The same points as in the above-described embodiment will be omitted. Of the elements disclosed in this embodiment, those corresponding to the members described in Embodiment 1 are assigned the same names as the members of Embodiment 1, and only the points different from those of Embodiment 1 will be described. 
     (Toner Pack Mounting Portion)) 
     Referring to  FIGS.  40  to  45   , the structure of the mounting portion  206  will be described. In this embodiment, the mounting portion  206  is a unit for mounting the toner pack  220 . 
     Part (a) of  FIG.  40    is an exploded perspective view of a mounting portion  206 . Part (b) of  FIG.  40    is an exploded perspective view of the mounting portion  206  as viewed in a direction different from that of part (a) of  FIG.  40   . Part (a) of  FIG.  41    and part (a) of  FIG.  42    are a perspective view illustrating the appearance of the mounting portion  206 , and a view as seen in the mounting direction M (direction of the rotational axis B), when the operating lever  208  is in the closed position, respectively. Part (b) of  FIG.  41    and part (b) of  FIG.  42    are a perspective view illustrating the appearance of the mounting portion  206 , and a view as seen in the mounting direction M (the direction of the rotational axis B), when the operating lever  208  is in the open position, as viewed in the mounting direction M, respectively.  FIG.  43    is a perspective view of the mounting portion  206  as viewed from the downstream side in the mounting direction M. Part (a) of  FIG.  44    is a perspective view of the apparatus-side shutter  209  as viewed from the upstream side in the mounting direction M. Part (b) of  FIG.  44    is a perspective view of the apparatus-side shutter  209  as viewed from a point different from that of part (a) of  FIG.  44   . Part (c) of  FIG.  44    is a top view of an apparatus-side shutter  209  as viewed in the mounting direction M. Part (a) of  FIG.  45    is a perspective view of a cover  210  as viewed from the upstream side in the mounting direction M. Part (b) of  FIG.  45    is a perspective view of the cover  210  as viewed from the downstream side in the mounting direction M. Part (c) of  FIG.  45    is a top view of the cover  210  as viewed in the mounting direction M. Part (d) of  FIG.  45    is a bottom view of the cover  210  as viewed in the mounting direction M. Part (e) of  FIG.  45    is a side view of the cover  210  as viewed in a direction perpendicular to the mounting direction M. 
     The mounting portion  206  shown in  FIGS.  40  and  41    is provided with a base frame  221  including a first frame  207 , a second frame  217 , and a cover  210 . The cover  210  and the second frame  217  are fixed to the first frame  207 . A first filter  218  having a predetermined air flow rate is mounted to an air hole  207   c  of the first frame  207 . Further, a second filter  219  having a predetermined air flow rate is also mounted to the second frame  217 . As shown in  FIG.  45   , the cover  210  is provided with an engaged portion  210   h  which engages with an engaging portion  207   b  (see part (b) of  FIG.  40    of the first frame  207  so that the cover  210  does not move relative to the first frame  207 . The first frame  207 , the cover  210 , and the second frame  217  may be an integral member instead of separate members. As shown in  FIGS.  40  and  43   , the second frame  217  is provided with an apparatus-side opening  217   a  (frame opening, receiving opening), and the apparatus-side opening  217   a  is in fluid communication with a toner accommodating chamber  36  (second accommodating portion) of the developing device  30  (see part (a) of  FIG.  1   ). The mounting portion  206  and the toner accommodating chamber  36  form a toner accommodating unit. 
     As shown in  FIG.  41   , the operating lever  208  and the apparatus-side shutter  209  (second shutter) are rotatable about the rotational axis B (central axis) relative to the base frame  221  in the rotational direction D (first rotation) and in the rotational direction E (second rotational direction). The rotational direction E is opposite to the direction of the rotational direction D. 
     As shown in part (a) of  FIG.  40   , the first frame  207  is provided with a positioning portion  207   a . The positioning portion  207   a  projects inward from the inner peripheral surface of the first frame  207  centered on the rotational axis B in the radial direction r of the imaginary circle VC centered on the rotational axis B. In addition, the operating lever  208  is provided with a drive transmission portion  208   a  (lever projection) and an operating portion  208   b . The drive transmission portion  208   a  is provided with a slit  208   c . The drive transmission portion  208   a  of the operating lever  208  is a projection projecting inward from the inner peripheral surface  208   d  centering on the rotational axis B of the operating lever  208  in the radial direction r of the imaginary circle VC centered on the rotational axis B. 
     As shown in  FIG.  44   , the apparatus-side shutter  209  is a cylindrical member provided with an open top end, a bottom surface  209   b , and on the apparatus-side lateral portion having an inner peripheral surface  209   h  (radial positioning) centered on the rotational axis B. The bottom surface  209   b  is provided with a center boss  209   d  (positioning shaft, shaft portion) and a restricted rib  209   c  (rotation restricted portion). A receiving opening  209   a  (second shutter opening, apparatus-side shutter opening) and a driven transmission portion  209   e  (pushed portion, shutter projection) are provided on the apparatus-side shutter lateral portion of the apparatus-side shutter  209 . The center boss  209   d  has a pack contact surface  209   g  (positioning in the mounting direction) facing upward. 
     The center boss  209   d  is a shaft having a central axis of the rotational axis B, and projects above the bottom surface  209   b  (in the direction opposite to the mounting direction M). As shown in part (c) of  FIG.  44   , the restricted rib  209   c  is provided outside the center boss  209   d  in the radial direction r of the imaginary circle VC centered on the rotational axis B. As shown in part (a) of  FIG.  44    and part (b) of  FIG.  44   , the restricted rib  209   c  projects upward from the bottom surface  209   b  in the direction of the rotational axis B. As shown in part (c) of  FIG.  44   , the driven transmission portion  209   e  is a projection which projects inward in the radial direction r of the imaginary circle VC. In addition, the driven transmission portion  209   e  is provided outside the restricted rib  209   c  in the radial direction r of the imaginary circle VC. As shown in part (b) of  FIG.  41   , an apparatus-side seal  211  is mounted around the receiving opening  209   a.    
     Here, the apparatus-side shutter  209  is movable relative to the base frame  221  between a closed position in which the receiving opening  209   a  is closed by the apparatus-side seal  211  and the cover  210 , and an open position in which said receiving opening is not closed by the cover  210  and is opened. As shown in part (a) of  FIG.  41    and part (a) of  FIG.  42   , the closed position is such that the receiving opening  209   a  of the apparatus-side shutter  209  and the apparatus-side opening  217   a  of the second frame  217  shown in  FIG.  43    are not in fluid communication with each other. As shown in part (b) of  FIG.  41    and part (b) of  FIG.  42   , the open position is a fluid communication position in which the receiving opening  209   a  of the apparatus-side shutter  209  and the apparatus-side opening  217   a  of the second frame  217  are in fluid communication with each other. As the apparatus-side shutter  209  rotates in the rotational direction D from the closed position (non-communication position) to the open position (communication position), the toner of the developing device  30  is enabled to replenish (supply) the toner into the accommodating chamber  36  from the toner pack  220  by way of the receiving opening  209   a . When the apparatus-side shutter  209  rotates in the rotational direction E from the open position to the closed position, it becomes impossible to supply toner from the toner pack  220  into the toner accommodating chamber  36  of the developing device  30  by way of the receiving opening  209   a.    
     The operating lever  208  and the apparatus-side shutter  209  are not directly engaged with each other, and therefore, the apparatus-side shutter  209  does not rotate even if the operating lever  208  is operated without the toner pack  220  mounted. 
     (Device Side Shutter Rotation Restriction Mechanism) 
     As shown in  FIG.  40   , the mounting portion  206  of the image forming apparatus  1  includes a rotation restricting mechanism  212  having a restricting member  213 , a releasing member  214 , a restricting spring  215 , and a releasing spring  216 . 
     Referring to  FIGS.  46  to  50   , The rotation restricting mechanism  212  will be described. In  FIGS.  49  and  50   , the cut surfaces of the cover  210 , the restricting member  213 , and the releasing member  214  are shaded for better illustration. 
     It may happen that when the toner pack  220  is not mounted on the mounting portion  206 , the apparatus-side shutter  209  is rotated more than a predetermined amount from the closed position to the open position by an impact (vibration) during distribution of the image forming apparatus  1  or by an erroneous operation by the user. If it happened, it might be difficult for the user to mount the toner pack  220  on the mounting portion  206  when using the image forming apparatus  1 . Details on this point will be described hereinafter. In view of this, the image forming apparatus  1  of this embodiment is provided with a rotation restricting mechanism  212  in order to restrict the rotation of the shutter  209  on the apparatus side from the closed position to the open position. 
     Part (a) of  FIG.  46    is a perspective view of a restricting member  213  as viewed from the upstream side in the mounting direction M. Part (b) of  FIG.  46    is a perspective view of the restricting member  213  as viewed from the downstream side in the mounting direction. Part (a) of  FIG.  47    is a perspective view of a releasing member  214  as viewed from the upstream side in the mounting direction M. Part (b) of  FIG.  47    is a top view of the releasing member  214  as viewed in the mounting direction M. Part (c) of  FIG.  47    is a perspective view of the releasing member  214  as viewed from the downstream side in the mounting direction M. Part (d) of  FIG.  47    is an enlarged view of a releasing claw  214   e  of the releasing member  214 . Part (a) of  FIG.  48    is a perspective view of a unit in which the restricting member  213  and the releasing member  214  are assembled. Part (b) of  FIG.  48    is a top view of the unit in which the restricting member  213  and the releasing member  214  are assembled as viewed in the mounting direction M. Part (c) of  FIG.  48    is a sectional view taken along a line X 214 -X 214  in part (b) of  FIG.  48   . Part (d) of  FIG.  48    is a bottom view of the unit in which the restricting member  213  and the releasing member  214  are assembled, as viewed in the mounting direction M.  FIG.  49    is a sectional view taken along a X 201 -X 201  in part (a) of  FIG.  42   , which is a sectional view taken along a line parallel to the rotational axis B in a state in which the rotation of the apparatus-side shutter  209  from the closed position to the open position is restricted by the rotation restricting mechanism  212 . Part (a) of  FIG.  50    is a cross-sectional view taken along a line X 202 -X 202  in  FIG.  49   . Part (b) of  FIG.  50    is a cross-sectional view taken along a line X 203 -X 203  in  FIG.  49   . Part (c) of  FIG.  50    is a cross-sectional view taken along a line X 204 -X 204  in  FIG.  49   . 
     As shown in  FIG.  49   , a restricting member  213 , a releasing member  214 , a restricting spring  215 , and a releasing spring  216  are provided inside the apparatus-side shutter  209 . 
     As shown in part (a) of  FIG.  46    and part (b) of  FIG.  46   , the restricting member  213  is an annular member provided with a central hole  213   i  centered on the rotational axis B. The restricting member  213  has a function of restricting the rotation of the apparatus-side shutter  209 , which will be described hereinafter. The restricting member has a lower surface  213   a , a first contact surface  213   b , a second contact surface  213   h , a second restricting surface  213   c  (rotation restriction portion), a contacted surface  213   e , a pair of locked surfaces  213   f , a release spring engaging portion  213   g  and a restriction spring engaging portion  213   k . The first contact surface  213   b  and the second contact surface  213   h  are end surfaces on the downstream side in the rotational direction D of the apparatus-side shutter  209 . The second restricting surface  213   c  is an end surface on the downstream side in the rotational direction E of the apparatus-side shutter  209 . 
     The locked surface  213   f  is an end surface (upper surface) on the upstream side in the mounting direction M. The lower surface  213   a  is an end surface (bottom surface) on the downstream side in the mounting direction M. The release spring engaging portion  213   g  is a projection projecting in the rotational direction E. The restriction spring engaging portion  213   k  is a recess recessed in the mounting direction M. 
     As shown in part (a) of  FIG.  47    and part (b) of  FIG.  47   , the releasing member  214  (guided member, engaged member) includes a pair of releasing claws  214   e  (first engaging claws and second engaging claws, a pair of engaged portions) having shapes of 180-degree rotationally symmetry centered on the rotational axis B. The releasing claw  214   e  extends in the direction opposite to the mounting direction M (upward). 
     As shown in part (d) of  FIG.  47   , the releasing claw  214   e  is provided with a first guided portion  214   e A (first contacted portion, first engaged portion) and a second guided portion  214   e B (second contacted portion, second engaged portion). As shown in part (a) of  FIG.  47    and part (b) of  FIG.  47   , the second guided portion  214   e B is placed at a position which is more remote from the rotational axis B than the first guided portion  214   e A in the radial direction r of the imaginary circle VC downwardly in the direction of the axis of rotation B. 
     As shown in part (d) of  FIG.  47   , the first guided portion  214   e A has a first guided surface  214   e   1  and a contact surface  214   f . The second guided portion  214   e B has a contact surface  214   a , a second guided surface  214   e   2  (first engaged surface), and a third guided surface  214   e   3  (second engaged surface). 
     As shown in part (b) of  FIG.  47   , the contact surface  214   f  and the contact surface  214   a  are end surface s, on the downstream side in the rotational direction E about the rotational axis B, of the releasing claw  214   e , and they are at the same positions in the circumferential direction of the imaginary circle VC. The contact surface  214   a  is placed outside the contact surface  214   f  in the radial direction r of the imaginary circle VC centered on the rotational axis B. 
     The first guided surface  214   e   1  is placed on the upstream side in the mounting direction M with respect to the contact surface  214   f  In other words, the first guided surface  214   e   1  is placed above any of the contact surface  214   f , the second guided surface  214   e   2 , and the third guided surface  214   e   3 . The second guided surface  214   e   2  is a surface facing upward. The second guided surface  214   e   2  is placed on the upstream side in the mounting direction M with respect to the contact surface  214   a . In other words, the second guided surface  214   e   2  is placed above the contact surface  214   a . The third guided surface  214   e   3  is a surface facing downward. The third guided surface  214   e   3  is placed on the downstream side in the mounting direction M with respect to the contact surface  214   a . In other words, the third guided surface  214   e   3  is placed below the contact surface  214   a . That is, the second guided surface  214   e   2  is above the third guided surface  214   e   3 . The contact surface  214   a  is between the second guided surface  214   e   2  and the third guided surface  214   e   3  in the mounting direction (direction of rotational axis B, gravity direction). 
     The releasing member  214  further includes a pair of rise restricted surfaces  214   c  (rising restricted portions), a pair of locking surfaces  214   d , a release spring engaging portion  214   g , and a contact surface  214   b.    
     The pair of rise restricted surfaces  214   c  and the pair of locking surfaces  214   d  are arranged so as to be 180 degrees symmetric with respect to the rotational axis B. As shown in part (a) of  FIG.  47    to part (c) of  FIG.  47   , the rise restricted surface  214   c  projects outward in the radial direction r of the imaginary circle VC beyond the outer peripheral surface centered on the rotational axis B of the releasing member  214 . The locking surface  214   d  is a surface (a surface facing downward) which projects from the outer peripheral surface of the releasing member  214  in the direction opposite to the mounting direction M and which faces the mounting direction M. The release spring engaging portion  214   g  is a projection projecting in the rotational direction D. The contact surface  214   b  is a surface facing upward. 
     In the state where the restricting member  213  and the releasing member  214  are assembled in, as shown in part (a) of  FIG.  48    and part (c) of  FIG.  48   , the locked surface  213   f  of the restricting member  213  is directly below the locking surface  214   d  of the releasing member  214  and faces the locking surface  214   d . Therefore, the structure is such that even if an attempt is made to move the restricting member  213  upward, it cannot be moved because the locked surface  213   f  of the restricting member  213  is locked to the locking surface  214   d  of the releasing member  214  unless the releasing member  214  is moved upward. As shown in part (c) of  FIG.  48   , the contact surface  214   b  of the releasing member  214  faces the contacted surface  213   e  of the restricting member  213 . Therefore, when the releasing member  214  is moved upward, the contact surface  214   b  comes into contact with the contacted surface  213   e  of the restricting member  213 , and the releasing member  214  and the restricting member  213  can integrally move upward. In addition, as shown in part (b) of  FIG.  48    and part (d) of  FIG.  48   , between the release spring engaging portion  213   g  of the restricting member  213  and the release spring engaging portion  214   g  of the releasing member  214 , there is provided a spring  216 . Further, the pair of releasing claws  214   e  project upward through the central hole  213   i  centered on the rotational axis B of the restricting member  213  beyond the upper surface of the restricting member  213 . 
     As shown in  FIG.  45   , the cover  210  includes a base cover portion  210 Aa and a wall portion  210 Bb extending upward from the base cover portion  210 Aa. 
     The base cover portion  210 Aa includes an upper surface  210   i  provided with a center hole  210   p  (cover opening) centered on the rotational axis B and a pair of eave portions  210   n , a first contacted surface  210   a , and a second contacted surface  210   b , a pair of third contacted surfaces  210   k , a first restricting surface  210   c , a pair of rise restricting surfaces  210   e , and a restriction spring engagement portion  210   m . The wall portion  210 Bb is provided with a side surface  210   f , a side surface  210   g , and the above-described engaged portion  210   h.    
     As shown in part (b) of  FIG.  45    and part (d) of  FIG.  45   , the first contacted surface  210   a  and the second contacted surface  210   b  are end surfaces on the downstream side in the rotational direction E. The third contacted surface  210   k  is an end surface on the downstream side in the rotational direction D. An eave portion  210   n  is provided on the upstream side of the third contacted surface  210   k  in the mounting direction M. As shown in part (c) of  FIG.  45   , the third contacted surface  210   k  is structured to be covered by the eave portion  210   n  as viewed from above in the direction of the rotational axis B so as not to be exposed. The pair of rise restricting surfaces  210   e  are surfaces facing the downstream side (downward) in the mounting direction M, and as shown in part (e) of  FIG.  45   , they include surfaces which extend so as to go in the mounting direction M (downward) as goes in the rotational direction D. The restriction spring engagement portion  210   m  is a cylindrical projection projecting in the mounting direction M. 
     Here, as shown in  FIG.  49   , the restricting member  213  and the releasing member  214  are rotatably supported by a large diameter portion  209   d   1  of the center boss  209   d  of the apparatus-side shutter  209 . In addition, a part of the rotation restricting mechanism  212  is covered by the upper surface  210   i  of the cover  210 . The center boss  209   d  is provided coaxially with the rotational axis B of the apparatus-side shutter  209 . As shown in  FIG.  49   , a restricting spring  215  (second elastic member, second urging member) is mounted between the cover  210  and the restricting member  213 . One end and the other end of the restricting spring  215  are engaged with the restriction spring engagement portion  210   m  of the cover  210  and the restriction spring engaging portion  213   k  of the restricting member  213 , respectively. As shown in part (b) of  FIG.  45    and part (d) of  FIG.  43   , the restricting spring engaging portion  210   m  is an annular rib centered on the rotational axis B, and is inserted into the inner diameter region of the restricting spring  215 . 
     The restricting member  213  is urged in the direction of arrow C in parallel with the rotational axis B by the urging force F 201  of the restricting spring  215 , and the lower surface  213   a  (see part (b) of  FIG.  46    contacts the bottom surface  209   b  of the apparatus-side shutter  209 . The arrow C direction is the mounting direction M (gravity direction) of the toner pack  220 . Further, as shown in  FIG.  50   , part (b) of  FIG.  48    and part (d) of  FIG.  48   , in the rotational direction of the apparatus-side shutter  209 , the releasing spring  216  (first elastic member, first urging member) is mounted between the restricting member  213  and the releasing member  214 . One end and the other end of the releasing spring  216  are engaged with the release spring engaging portion  213   g  of the restricting member  213  and the release spring engaging portion  214   g  of the releasing member  214 , respectively. As shown in part (b) of  FIG.  50   , the restricting member  213  receives a moment M 201  in the rotational direction D by the urging force F 202  of the releasing spring  216 , and the first contact surface  213   b  of the restricting member  213  is brought into contact with the first contacted surface  210   a  of the cover  210 , or the second contact surface  213   h  of the restricting member  213  is brought into contact with the second contacted surface  210   b  of the cover  210 . By this, the restricting member  213  is restricted from rotating in the rotational direction D. 
     On the other hand, as shown in part (c) of  FIG.  50   , the releasing member  114  receives the moment M 202  in the rotational direction E by the urging force F 203  of the release spring  116 , and at least one of the pair of contact surfaces  214   a  is brought into contact with the corresponding one of the third contacted surfaces  210   k  of the cover  210 . By this, the rotation of the releasing member  114  in the rotational direction E is restricted, and the position thereof in the rotational direction E relative to the cover  210  is determined. 
     Here, the cover  210  is fixed to the first frame  207 . Therefore, as shown in part (a) of  FIG.  50   , the restricted rib  209   c  of the apparatus-side shutter  209  is placed between the first restricting surface  210   c  of the cover  210  and the second restricting surface  213   c  of the restricting member  213 . For this reason, the rotation of the apparatus-side shutter  209  in the rotational direction D (direction from the closed position to the open position) is restricted by the second restricting surface  213   c  of the restricting member  213 . The rotation of the apparatus-side shutter  209  in the rotational direction E (direction from the open position to the closed position) is restricted by the first restricting surface  210   c  of the cover  210 . 
     (Rotation Restriction Release Method) 
     Referring to  FIGS.  51  to  54   , a method of releasing the rotation restriction of the apparatus-side shutter  209  by the rotation restricting mechanism  212  will be described. For better illustration, the cut surfaces of the cover  210 , the restricting member  213 , and the releasing member  214  are shaded. 
     Part (a) of  FIG.  51    is a sectional view, taken along a line (same as that in  FIG.  49   ) parallel with the rotational axis B, of the mounting portion  206  in a state in which the rotation restriction of the apparatus-side shutter  209  by the rotation restricting mechanism  212  is released. Part (b) of  FIG.  51    is a cross-sectional view taken along a line X 205 -X 205  of part (a) of  FIG.  51   .  FIG.  51    shows the state of the mounting portion  206  in which the rotation restriction of the apparatus-side shutter  209  is released when the toner pack  220  is not mounted, for convenience of explanation. 
     After the first step of rotating the releasing member  214  in the rotational direction D from the state of  FIGS.  49  and  50   , the second step of moving the releasing member  214  in the arrow G direction (upward) shown in  FIG.  49    is carried out. In this embodiment, the first step and the second step are executed by the operation of mounting the toner pack  220  on the mounting portion  106 . This will be described after explaining the structure of the toner pack  220 . Here, only the structure of the mounting portion  206  will be described. In the second step, the contact surface  214   b  of the releasing member  214  contacts the contacted surface  213   e  of the restricting member  213 , and the releasing member  214  and the restricting member  213  are integrally moved in the direction of arrow G against the urging force F 201  of the restricting spring  215 . Through this second step, the state of releasing the rotation restriction shown in  FIG.  51    is reached. The arrow G direction is the direction opposite to the mounting direction M of the toner pack  220 . 
     In the state that the rotation restriction is released, as shown in part (b) of  FIG.  51   , the second restricting surface  213   c  of the restricting member  213  is retracted upward, from the movement locus (rotation locus) of the restricted rib  209   c  between the closed position and the open position of the apparatus-side shutter  209 . The position of the restricting member  213  is referred to as a restriction release position (release position). And, the restricted rib  209   c  (apparatus-side shutter  209 ) can move between the first restricting surface  210   c  and the third restriction surface  210   d  of the cover  210 . The distance between the first restricting surface  210   c  and the third restriction surface  210   d  is such that the apparatus-side shutter  209  can rotate and move between the closed position and the open position. Therefore, the rotation restriction of the apparatus-side shutter  209  is released between the closed position and the open position. That is, the apparatus-side shutter  209  can rotate from the closed position to the open position in the rotational direction D about the rotational axis B. On the other hand, the rotation of the apparatus-side shutter  209  in the rotational direction E from the closed position is restricted by the first restricting surface  210   c  of the cover  210 . The amount of movement of the releasing member  214  in the arrow G direction (upward direction) suffices if it is more than the amount necessary to the position in which the second restricting surface  213   c  of the restricting member  213  which moves integrally with the releasing member  214  does not overlap with the restricted rib  209   c  of the apparatus-side shutter  209  in the direction of the rotational axis B. 
     Here, the rotation restricting mechanism  212  is structured so that the rotation restriction of the apparatus-side shutter  209  is not released when the rotation restricting mechanism  212  is operated starting at the second step without executing the operation of the first step. 
     Part (a) of  FIG.  52    is a side view of part (a) of  FIG.  50    as viewed in the direction of arrow G. Part (b) of  FIG.  52    is a sectional view taken along the line X 206 -X 206  of part (a) of  FIG.  52   . Part (c) of  FIG.  52    shows a state in which the restricting member is moved in the direction of arrow G from the state of part (a) of  FIG.  52    and part (b) of  FIG.  52   . For better illustration, only the cover  210 , the restricting member  213 , the releasing member  214 , the restricting spring  215 , and the releasing spring  216  are shown, and the restricting member  213  is not shown in a cross-section. 
     As shown in part (a) of  FIG.  52   , part (b) of  FIG.  52   , part (b) of  FIG.  45   , and part (d) of  FIG.  45   , the cover  210  is provided with a rise restricting surface  210   e  (rise restricting portion), and the releasing member  214  is provided with an rise restricted surface  214   c  (rise restricted portion). When the restricting member  213  is moved in the arrow G direction without being rotated in the rotational direction D from this state, the locked surface  213   f  of the restricting member  213  comes into contact with the locking surface  214   d  of the releasing member  214 . The same structure is provided on the opposite side with respect to the rotational axis B, the restricting member  213  and the releasing member  214  are integrally moved in the arrow G direction (upward). As a result, as shown in part (c) of  FIG.  52   , the rise restricted surface  214   c  of the releasing member  214  contacts the rise restricting surface  210   e  of the cover  210  to restrict the movement of the releasing member  214  in the arrow G direction, and therefore, the restricting member  213  which moves integrally with the releasing member  214  is also restricted in the movement in the direction of arrow G. Since the amount of movement of the restricting member  213  in the arrow G direction is insufficient, the restricted rib  209   c  of the apparatus-side shutter  209  is maintained in the rotation restricted state by the first restricting surface  210   c  and the second restricting surface  213   c  as shown in part (a) of  FIG.  50   . At this time, the position (region) in the rotational direction about the rotational axis B of the releasing member  214  at this time is a rise restricted position (rising restricting region). That is, the rise restriction position is the position of the releasing member  214  when the rise restricted surface  214   c  of the releasing member  214  overlaps with the rise restricting surface  210   e  of the cover  110  as viewed in the direction of the rotational axis B. Further, as shown in part (c) of  FIG.  52   , the rise restricting surface  210   e  and the rise restricted surface  214   c  are inclined so that a force F 204  received by the rise restricted surface  214   c  from the rise restricting surface  210   e  has a component in a direction of an arrow H. The rise restricting surface  210   e  and the rise restricted surface  214   c  are inclined downward toward a downstream side in the rotational direction D. The arrow H direction component of the force F 204  applies a moment M 203  to the releasing member  214  in the rotational direction EBay this, even if the restricting member  213  tends to move in the arrow G direction (upward) due to the vertical vibration of the image forming apparatus  1  during transportation, the releasing member  214  is not easily rotate in the rotational direction D, and therefore, the restriction in the direction of arrow G by the cover  210  is not released. 
     Next, referring to  FIGS.  52  and  53   , a process of releasing the rotation restriction of the apparatus-side shutter  209  through the first step and the second step will be described. The first step is a step of rotating the releasing member  214  in the rotational direction D against the moment M 202  by the releasing spring  216  until the rise restricted surface  214   c  of the releasing member  214  is out of contact with the rise restricting surface  210   e  of the cover  210 . 
     Part (a) of  FIG.  53    shows a state in which the first step has been passed from the state in part (a) of  FIG.  52   . Part (b) of  FIG.  53    is a sectional view taken along the line X 207 -X 207  in part (a) of  FIG.  53   . Part (c) of  FIG.  53    shows a state in which the second step has been passed from the state in part (b) of  FIG.  53   . Part (a) of  FIG.  54    shows a state in which the releasing member  214  is further rotated in the rotational direction D from part (a) of  FIG.  53   . Part (b) of  FIG.  54    is a sectional view taken along the line X 208 -X 208  of part (a) of  FIG.  54   . As in  FIG.  52   ,  FIGS.  53  and  54    show only the cover  210 , the restricting member  213 , the releasing member  214 , the restricting spring  215 , and the releasing spring  216  for better illustration, and the restricting member  213  is not in a cross-section. 
     As shown in part (a) of  FIG.  53   , as viewed in the direction of the rotational axis B, the rise restricted surface  214   c  of the releasing member  214  and the rise restricting surface  210   e  of the cover  210  do not overlap with each other. Therefore, as shown in part (b) of  FIG.  53   , the restricting member  213  can move integrally with the releasing member  214  in the direction of arrow G. At this time, the position (region) in the rotational direction about the rotational axis B of the releasing member  214  is a rise restriction release position (rise restriction release region). That is, the rise restriction release position is the position (region) of the releasing member  214  when the rise restricted surface  214   c  of the releasing member  214  does not overlap with the rise restricting surface  210   e  of the cover  210  as viewed in the direction of the rotational axis B. The amount of rotation of the releasing member  214  in the rotational direction D in the first step suffices if it is more than an amount by which, as viewed in the direction of the rotational axis B, the rise restricted surface  214   c  of the releasing member  214  does not overlap with the rise restricting surface  210   e  of the cover  210 . 
     The method of releasing the rotation restriction of the apparatus-side shutter  209  includes a first step and a second step after the first step. The first step is a step of rotating the releasing member  214  from the rise restriction release position to the rise restriction release position in the rotational direction D. The second step is a step of moving the releasing member upward together with the restricting member  213  so that the restricting member  213  moves from the restriction position to the restriction release position while the releasing member  214  is in the rise restriction release position. The second step of this embodiment may include an operation of rotating the releasing member  214  in the rotational direction D or the rotational direction E. For example, it may be as shown in  FIG.  54    that in the first step, the releasing member  214  is rotated more in the rotational direction D than in part (a) of  FIG.  53   , and in the second step, the releasing member  214  is moved in the arrow G direction and is rotated in the rotational direction E. 
     (Toner Pack) 
     Referring to  FIGS.  55  and  56   , an overall structure of the toner pack  220  will be described. Part (b) of  FIG.  55    is a front view of the toner pack  220  when the pack side shutter  203  is in the closed position. Part (d) of  FIG.  55    is a front view of the toner pack  220  when the pack side shutter  203  is in the open position. Part (a) of  FIGS.  55  and  55    ( c ) are left side views and right side views of the toner pack  220  of part (b) of  FIG.  55   , respectively.  FIG.  56    is an exploded perspective view of the toner pack  220 . The arrow N direction and the arrow U direction are parallel to the rotational axis A. When the toner pack  220  is in the mounting attitude, the arrow N direction is the vertical downward direction (gravity direction), and the arrow U direction is the vertical upward direction. 
     The toner pack  220  includes an accommodating portion  201  (first accommodating portion) for accommodating toner, a nozzle  202  (discharging portion, nozzle portion, pipe, tube, valve), and a pack-side shutter  203  (container shutter, rotatable member). As shown in  FIG.  55   , the accommodating portion  201  is provided on the side of the first end portion in the first direction D 1 , and the nozzle  102  and the pack side shutter  203  are provided on the side of the second end portion opposite to the first end portion in the first direction D 1 . That is, the accommodating portion  201  and the nozzle  202  are structured to be arranged in the first direction D 1 . The accommodating portion  201  in this embodiment is a pouch formed by pouching a flexible polypropylene sheet. The accommodating portion  201  is not limited to the pouch, and may be a resin bottle or a container made of paper, vinyl or the like. 
     As shown in  FIG.  56   , on the side surface  202   c  (first outer surface) of the nozzle  202  extending in the first direction D 1 , a discharge opening  202   a  (opening, nozzle opening, a first opening) configured for fluid communication with the inside of the accommodating portion  201 . The toner stored in the accommodating portion  201  is structured to be discharged to the outside of the toner pack  220  through the discharge opening  202   a  of the nozzle  202 . The nozzle  202  may be integrally structured with the accommodating portion  201 . Further, a seal (not shown) may be provided between the accommodating portion  201  and the discharge opening  202   a  of the nozzle  202 , and the accommodating portion  201  and the discharge opening  202   a  may be brought into fluid communication with each other when the seal is removed. Further, the discharge opening  202   a  does not have to be the final discharge opening for discharging toner from the toner pack  220  to the outside of the toner pack  220 . 
     A pack-side shutter  203  is provided on the outside of the side surface  202   c  of the nozzle  202 . The pack-side shutter  203  is mounted rotatably around a rotational axis A (first rotational axis, central axis) extending in a direction along the first direction D 1 , and is provided with an opening  203   a  (rotatable member opening, first shutter opening) in the side surface  203   d  (first rotatable member outer surface, rotatable member side surface portion) extending in the direction of the rotational axis A as shown in  FIG.  56   . The pack-side shutter  203  is provided outside the side surface  202   c  of the nozzle  202  in the radial direction r of the imaginary circle VC centered on the rotational axis A. The side surface  202   c  of the nozzle  202  is a curved surface that is convex toward the outside in the radial direction r of the imaginary circle VC centered on the rotational axis A. That is, the discharge opening  202   a  faces the outside in the radial direction r (the direction perpendicular to the rotational axis A). Further, the inner surface of the pack-side shutter  203  (the surface facing the side surface  202   c ) is a curved surface along the side surface  202   c  of the nozzle  202 , and a substantially rectangular pack-side seal  205  is mounted thereon. 
     As shown in part (b) of  FIG.  55    and part (d) of  FIG.  55   , the pack-side shutter  203  is movable between a closing position in which the pack-side seal  205  closes the discharge opening  202   a  of the nozzle  202  and an opening position in which the discharge opening  202   a  is opened, in the rotational direction K (first rotational direction) and the rotational direction L (second rotational direction) opposite to the rotational direction K about the rotational axis A. When the pack-side shutter  203  is in the open position, the discharge opening  202   a  of the nozzle  202  is uncovered through the opening  203   a.    
     When the pack-side shutter  203  in the closed position shown in part (b) of  FIG.  55    is rotated in the direction of arrow K about the rotational axis A, the pack-side shutter  203  is moved to the open position shown in part (d) of  FIG.  55   . On the contrary, when the pack side shutter  203  is rotated from the open position in the direction of an arrow L, it is moved to the closed position. In the rotational operation of the pack-side shutter  203 , the pack-side shutter  203  slides on the side surface  202   c  of the nozzle  202  by way of the pack-side seal  205 . 
     Referring to  FIGS.  57  to  61   , the detailed structure of the nozzle  202  and the pack-side shutter  203  will be described. The arrow N direction is the direction from the accommodating portion  201  toward the nozzle  202 , and the U direction is the opposite thereto. The arrow N direction and the arrow U direction are directions parallel to the rotational axis A. When the toner pack  220  is in the mounting attitude, the arrow N direction is the vertical downward direction (gravity direction), and the arrow U direction is the vertical upward direction. 
     Part (a) of  FIG.  57    is an enlarged view of the neighborhood of the nozzle  202  when the pack-side shutter  203  is in the closed position. Part (b) of  FIG.  57    is a view of the toner pack  220  as viewed in the direction of arrow U in part (a) of  FIG.  57   . Part (a) of  FIG.  58    is an enlarged perspective view of the neighborhood of the nozzle  202  when the pack-side shutter  203  is in the open position. Part (b) of  FIG.  58    is a side view of the toner pack  220  as viewed in the direction of arrow U in part (a) of  FIG.  58   . Part (c) of  FIG.  58    is an enlarged view of the nozzle  202  in part (a) of  FIG.  58   , as viewed from the front side. Part (a) of  FIG.  59    is a perspective view of the neighborhood of the nozzle  202  as viewed from the side opposite to that in part (a) of  FIG.  57   . Part (b) of  FIG.  59    is an enlarged perspective view of the projecting portion  202   b  of part (a) of  FIG.  59   . Part (c) of  FIG.  59    is an enlarged view of the projecting portion  202   b  as viewed in a direction perpendicular to the rotational axis A. Part (a) of  FIG.  60    is an enlarged perspective view of the projecting portion  202   b . Part (b) of  FIG.  60    is a partial enlarged view of the projecting portion  202   b  of part (b) of  FIG.  57   . Part (a) of  FIG.  61    and part (b) of  FIG.  61    are a front view and a rear view of the nozzle  202 , respectively. Part (a) of  FIG.  61    and part (b) of  FIG.  61    are illustrations of the neighborhood of the nozzle  202  as viewed in a direction parallel to the surface  202   d   1  and the surface  202   d   2  of the nozzle  202  (direction perpendicular to the rotational axis A). 
     As shown in part (a) of  FIG.  61    and part (b) of  FIG.  57   , the nozzles  102  is provided with a positioned portion  202   d  having a surface  202   d   1  (first nozzle surface, first opposing surface) and surface  202   d   2  (second nozzle surface, second opposing surface) which are arranged in the arrow R direction (second direction D 2 ) with a gap therebetween and which extend in a direction crossing with the arrow R direction. The arrow R direction is a direction perpendicular to the first direction D 1 . As shown in part (b) of  FIG.  57   , the surfaces  202   d   1  and  202   d   2  in this embodiment extend in a direction perpendicular to the arrow R direction and are parallel to each other. That is, the arrow R direction is the normal direction of the surface  202   d   1  and the surface  202   d   2 . The positioned portion  202   d  engages with the positioning portion  207   a  (part (a) of  FIG.  40   ) of the first frame  207  when the toner pack  220  is mounted on the mounting portion  206 . By this, the position of the nozzle  202  in the arrow R direction (the position in the rotational direction about the rotational axis A) relative to the first frame  207  (base frame  221 ) is determined. In part (b) of  FIG.  57   , the straight line CL 1  (first imaginary straight line) which passes through the center between the surface  202   d   1  and the surface  202   d   2  in the arrow R direction and which extends in the direction perpendicular to the arrow R direction is in a phase rotated by about 90° with respect to the straight line CL 2  (second imaginary straight line) which passes at the center of the discharge opening  202   a  and the rotational axis A. That is, The straight line CL 2  resulted by rotating the straight line CL 1  by 90 degrees about the rotational axis A passes through the discharge opening  202   a  of the nozzle  202 . 
     Further, as shown in  FIGS.  57  and  61   , a surface  202   e   1  and a surface  202   e   2  are provided on the downstream side of the surface  202   d   1  and the surface  202   d   2  in the N direction in the direction of the rotational axis A, respectively. As shown in part (b) of  FIG.  57   , the surfaces  202   e   1  and  202   e   2  extend in the radial direction r of the imaginary circle VC centered on the rotational axis A. 
     In  FIG.  61   , a side surface  202   e   3  (second outer surface) is provided between the surfaces  202   d   1  and  202   d   2  and between the surfaces  202   e   1  and  202   e   2  in the direction of arrow R. The side surface  202   e   3  is recessed inward in the radial direction r with respect to the side surface  202   c . The surface  202   d   1 , the surface  202   d   2 , the side surface  202   e   3 , the surface  202   e   1 , the surface  202   e   2  and the side surface  202   e   3  form a recess  202   e  (nozzle recess). 
     The surface  202   d   1  and the surface  202   d   2  do not necessarily have to be parallel as in this embodiment. The surface  202   d   1  and the surface  202   d   2  may be surfaces extending in the radial direction r of the imaginary circle VC centered on the rotational axis A. 
     Further, part (a) of  FIG.  61    is a view of the neighborhood of the nozzle of the toner pack  220  in which the pack side shutter  203  is in the closed position, as viewed in the direction perpendicular to the direction of the rotational axis A. As shown in part (a) of  FIG.  61   , the opening  203   a  is provided in the side surface  203   d  of the pack-side shutter  203 , and at least a part of the recess  202   e  (surface  202   e   1 , surface  202   e   2 , side surface  202   e   3 ) of the nozzle  202  is exposed to the outside through the opening  203   a . At least the surfaces  202   d   1  and  202   d   2  are structured to be exposed through the opening  203   a  of the pack-side shutter  203  taking the closed position. This is because, the surfaces  202   d   1  and the surfaces  202   d   2  are to be engaged with the positioning portion  207   a  of the first frame  207  when the toner pack  220  is mounted on the mounting portion  206  with the pack side shutter  203  closed. 
     Further, as shown in part (b) of  FIG.  57    a driven transmission portion  203   b  (rotatable member recess) is provided on the outer surface of the pack-side shutter  203  on the opposite side of the rotational axis A of the recess  202   e  (opening  203   a  of the pack-side shutter  203 ) of the nozzle  202 , as the neighborhood of the nozzle  202  is viewed in the direction of the rotational axis A (first direction D) when the pack side shutter  203  is in the closed position. As shown in part (b) of  FIG.  61   , both the surface  203   b   1  and the surface  203   b   2  of the driven transmission portion  203   b  extend in a direction perpendicular to the arrow R direction (direction of the rotational axis A). Part (a) of  FIG.  59    is an enlarged perspective view of the neighborhood of the pack-side shutter  203  as viewed from the side where the driven transmission portion  203   b  is disposed. Between the surfaces  203   b   1  and  203   b   2 , there is provided a side surface  203   b   3  (second rotatable member outer surface, rotatable member side surface portion) recessed inward in the radial direction from the side surface  203   d . The driven transmission portion  203   b  comprises the surface  203   b   1 , the surface  203   b   2 , and the side surface  203   b   3 . Further, the rib  203   e  is provided on the side surface  203   b   3 . 
     When the pack-side shutter  203  is rotated in the rotational direction K from the closed position shown in  FIG.  57   , the pack-side shutter  203  takes an open position, and the outlet  202   a  of the nozzle  202  is exposed through the opening  203   a  of the pack-side shutter  203 , as shown in  FIG.  58   . 
     Further, as shown in part (a) of  FIG.  57    and part (a) of  FIG.  59   , the pack-side shutter  203  is provided with a radial positioning portion  203   f  projecting outward in the radial direction beyond the side surface  203   d . The radial positioning portion  203   f  is provided on the upstream side of the pack side shutter  203  in the N direction in the direction of the rotational axis A. The radial positioning portions  203   f  are provided at each of the three positions at intervals in the rotational direction of the pack-side shutter  203 . 
     The nozzle  202  in this embodiment is includes a passage through which the toner passes and the discharge opening  202   a  for discharging the toner from the nozzle  202 . The cross-sectional area of the passage through which the toner of the nozzle  202  passes may be made smaller, larger, or even toward the discharge opening  202   a . The cross-sectional area and length of the passage of the nozzle  202  may be appropriately changed depending on the required toner discharge, and are not restrictive. Further, the discharge opening  202   a  of the nozzle  202  does not have to be the most downstream opening from which the toner is discharged from the toner pack  220 . The toner discharged from the discharge opening  202   a  of the nozzle  202  may be discharged to the outside of the toner pack  220  after passing through a passage of a member different from the nozzle  202 . 
     The pack-side shutter  203  may be a rotatable member which is provided with a driven transmission portion  203   b  but does not have a shutter function and therefore the discharge opening  202   a  of the nozzle  202  is open regardless of the rotational position. In such a case, it may be that the discharge opening  202   a  of the nozzle  202  is closed by a seal (not shown) when the toner pack  220  is not mounted to the mounting portion  206 , and is by sealed by the mounting operation to the mounting portion  206  or after the mounting operation. Further, the toner pack  220  which is not provided with the pack side shutter  203  may be used. 
     (Restriction Releasing Portion of Toner Pack) 
     Referring to  FIGS.  55  to  61   , the restriction releasing portion  204  will be described. Here, as shown in  FIG.  55   , the toner pack  220  is oriented in a predetermined direction in which the side of the second end portion (the nozzle  202  side) of the toner pack  220  is below the side of the first end portion (the toner accommodating portion side). In other words, the toner pack  220  is oriented in an attitude (predetermined orientation) in which the rotational axis A is in the vertical direction (gravity direction) and in which, at least a part of the nozzle  202  is below the accommodating portion  201 . The attitude of the toner pack  220  at this time is a mounting attitude to the mounting portion  206  of the image forming apparatus  1 . At this time, in  FIGS.  55  to  61   , the N direction is the vertical downward direction (gravity direction), and the U direction is the vertical upward direction. 
     The nozzle  202  is provided with a projecting portion  202   b  (projecting portion, engaging portion) which projects (protrudes) in the arrow N direction (downward) beyond the end surface  203   c  of the pack side shutter  203  in the arrow N direction. As shown in part (a) of  FIG.  57    and part (b) of  FIG.  57   , the projecting portion  202   b  is a cylindrical portion centered on the rotational axis A. Further, as shown in  FIG.  55   , the accommodating portion  201 , the nozzle  202  (pack side shutter  203 ), and the projecting portion  202   b  are arranged in the order named in the N direction, which is the mounting direction of the toner pack  220  to the mounting portion  206 . 
     As the projecting portion  202   b  is viewed in the direction of the rotational axis A, as shown in part (b) of  FIG.  57   , the projecting portion  202   b  is on the side closer to the rotational axis A than the driven transmission portion  203   b  of the pack-side shutter  203 , in the radial direction r of the imaginary circle VC. 
     The projecting portion  202   b  has a projecting portion end surface  202   b   2  (positioning surface in the mounting direction) which is an end surface in the N direction. The projecting portion  202   b  is provided with a hole having an inner peripheral surface  202   b   1  (guide inner peripheral surface, positioning inner peripheral surface) facing inward in the radial direction r with the rotational axis A as the central axis. 
     The inner peripheral surface  202   b   1  of this embodiment is a cylindrical surface centered on the rotational axis A as shown in part (b) of  FIG.  60   . However, the present invention is not limited to such an example. Part (a) of  FIG.  71    is an enlarged perspective view of a projecting portion  202   b  having an inner peripheral surface structure different from that of this embodiment, and part (b) of  FIG.  71    shows the projecting portion  202   b  of part (a) of  FIG.  71    as viewed in the direction of the rotational axis A. The inner peripheral surface  202   b   10  comprises a plurality of flat surfaces which inscribes the imaginary circle so that the position of the center (central axis) of an imaginary circle VC 2  is determined with respect to the projecting portion  202   b . The central axis of the imaginary circle VC 2  is coincident with the rotational axis A. The inner peripheral surface of the projecting portion  202   b  does not necessarily have to be a surface in which a central axis can be defined. Any inner peripheral surface may be used as long as the toner pack  220  can be mounted to the mounting portion  206  while dodging the center boss  209   d.    
     As shown in part (a) of  FIG.  57   , part (a) of  FIG.  58   , and part (c) of  FIG.  58   , the projecting portion  202   b  projects downward from the end surface  203   c  of the pack-side shutter  203  beyond the discharge opening  202   a . In this embodiment, the projecting portion  202   b  is provided on the nozzle  202  so as to project from the end surface  202   j  (bottom surface) in the direction of the rotational axis A of the nozzle  202  as shown in part (b) of  FIG.  62   . In addition, as shown in  FIG.  56   , the projecting portion  202   b  projects downward beyond the lower end surface  202   j  of the nozzle  202 . In this embodiment, the end surface  203   c  of the pack-side shutter  203  and the end surface  202   j  of the nozzle  202  are end surfaces perpendicular to the rotational axis A, but the present invention is not limited thereto. These surfaces may be any surface if it extends in a direction crossing the rotational axis A as viewed in a direction perpendicular to the rotational axis A. 
     As shown in part (c) of  FIG.  58   , an opening width L 1  of the nozzle  202  in the direction of the rotational axis A of the discharge opening  202   a , and a width L 2  measured from the lower end of the discharge opening  202   a  to the end surface  203   c  of the pack-side shutter  203  preferably satisfy 0.09&lt;L 2 /L 1 &lt;2.2. 
     Further, as shown in  FIG.  56   , the projecting portion  202   b  projects beyond the end surface  202   j  of the nozzle  202 . In this embodiment, the end surface  203   c  of the pack-side shutter  203  and the end surface  202   j  of the nozzle  202  are end surfaces perpendicular to the rotational axis A, but the present invention is not limited to this example. These surfaces may be any surface which extends in a direction crossing the rotational axis A as viewed in a direction perpendicular to the rotational axis A. 
     Further, as shown in part (b) of  FIG.  58   , It is understood that as viewed in the direction of the rotational axis A, when the pack side shutter  203  is in the open position, the opening  203   a  of the pack side shutter  203  overlaps the discharge opening  202   a  in the circumferential direction of the imaginary circle VC. 
     The projecting portion  202   b  is provided with a restriction releasing portion  204  including a first restriction releasing portion  204   a  (first projection) and a second restriction releasing portion  204   b  (second projection). Detailed structures of the restriction releasing portion  204  will be described, referring to part (b) of  FIG.  59   , part (c) of  FIG.  59   , part (a) of  FIG.  60   , part (b) of  FIG.  60   , part (a) of  FIG.  62   , and part (b) of  FIG.  62   . 
     The first restriction releasing portion  204   a  includes a first slope  204   a   1  (first inner engaging surface, first downward surface, first downward guide surface, first force applying surface, first push surface), a second slope  204   a   2  (first outer engaging surface, second downward surface, second downward guide surface, second force applying surface, second push surface) and a third slope  204   a   3  (second engaging surface, first upward surface, upward guide surface)). 
     When the toner pack  220  is oriented in the predetermined direction ( FIG.  50   ) described above, the first slope  204   a   1  and the second slope  204   a   2  have surfaces which face in the arrow N direction (downward) and which extend such that they go in the direction of the arrow U (upward) as go in the rotational direction K (first rotational direction) about the rotational axis A. In addition, as shown in part (c) of  FIG.  59   , as viewed in the direction perpendicular to the rotational axis A, the first slope  204   a   1  and the second slope  204   a   2  extend such that they go in the U direction (upward) as go in the first horizontal direction hz 1  of the horizontal direction. Further, when the rotational direction K is the first circumferential direction of the circumferential direction of the imaginary circle VC, the first slope  204   a   1  and the second slope  204   a   2  face in the arrow N direction (downward) and extend such that they go in the arrow U direction as go in the first circumferential direction. 
     The third slope  204   a   3  is a surface which faces the arrow U direction (upward) and which extends such that it goes in the arrow U direction (upward) as goes in the rotational direction L (second rotational direction) about the rotational axis A. In addition, as shown in part (c) of  FIG.  59   , the third slope  204   a   3  has the surface which extends such that it goes in the arrow U direction (upward) as goes in the second horizontal direction hz 2  which is opposite to the first horizontal direction hz 1  of the horizontal direction, as viewed in the direction perpendicular to the rotational axis A. Further, when the rotational direction L is a second circumferential direction which is opposite to the first circumferential direction in the circumferential direction of the imaginary circle VC, the third slope  204   a   3  faces in the arrow U direction (upward direction) and extend such that it goes in the arrow U direction (upward) as goes in the second circumferential direction. 
     The downstream end of the second slope  204   a   2  in the rotational direction K and the downstream end of the third slope  204   a   3  in the rotational direction L are connected with each other by a connecting portion  204   a   23 . Further, as shown in part (c) of  FIG.  59   , as viewed in the direction perpendicular to the rotational axis A, the downstream end of the second slope  204   a   2  in the first horizontal direction hz 1  and the downstream end of the third slope  204   a   3  in the second horizontal direction hz 2  are connected with each other by the connecting portion  204   a   23 . 
     The third slope  204   a   3  is above the second slope  204   a   2 . Viewed in the direction of the rotational axis A, the third slope  204   a   3  overlaps with the second slope  204   a   2 . In this embodiment, although the entire third slope  204   a   3  is above the second slope  204   a   2 , It will suffice if at least a part of the third slope  204   a   3  is above the second slope  204   a   2 . 
     As shown in part (b) of  FIG.  60   , at least a part of the first slope  204   a   1  is placed at a position which is closer to the rotational axis A than the second slope  204   a   2  in the radial direction r in the circumferential direction of the imaginary circle VC and which is different from that of the second slope  204   a   2 . 
     In part (b) of  FIG.  60   , a radius R 204   a   1  measured from the rotational axis A to an inner end (edge line) of the first slope  204   a   1  is shorter than the radius R 204   a   2  measured from the rotational axis A to the inner end (edge line) of the second slope  204   a   2 . That is, at least a part of the first slope  204   a   1  is placed closer to the rotational axis A than the second slope  204   a   2  in the radial direction r. 
     Further, in part (b) of  FIG.  60   , two regions of the first slope  204   a   1  separated by an imaginary straight line VL 204   a   1  passing through the rotational axis A and the most downstream end, in the rotational direction L, of the second slope  204   a   2  are an upstream side region  204   a   12  and a downstream side region  204   a   11  in the rotational direction K. In this case, the second slope  204   a   2  is not provided on the outside of the upstream region  204   a   12  in the radial direction r. That is, at least a part of the first slope  204   a   1  (upstream side region  204   a   12 ) is provided at a position different from that of the second slope  204   a   2  in the circumferential direction of the imaginary circle VC. Similarly, the two regions of the first slope  204   b   1  separated by an imaginary straight line VL 204   b   1  passing through the rotational axis A and the most upstream end, in the rotational direction K, of the second slope  204   b   2  are an upstream side region  204   b   12  and a downstream side region  204   b   11  in the rotational direction L. In this case, outside the upstream region  204   b   12  in the radial direction r, the second slope  204   b   2  is not provided. That is, at least a part of the first slope  204   b   1  (upstream side region  204   b   12 ) is provided at a position different from that of the second slope  204   b   2  in the circumferential direction of the imaginary circle VC. That is, in the first restriction releasing portion  204   a , the upstream region  204   a   12  of the first slope  204   a   1  is on the upstream side of the second slope  204   a   2  in the rotational direction K. Further, in the second restriction releasing portion  204   b , the upstream side region  204   b   12  of the first slope  204   b   1  is on the upstream side of the second slope  204   b   2  in the rotational direction K. 
     Further, as shown in part (c) of  FIG.  59   , as viewed in the direction perpendicular to the rotational axis A, at least a part of the first slope  204   a   1  is at a position different from that of the second slope  204   a   2  in the horizontal direction (first horizontal direction hz 1  or second horizontal direction hz 2 ). On the other hand, at least a part of the third slope  204   a   3  is provided on the downstream side (upper side) of at least a part of the second slope  204   a   2  in the arrow U direction. That is, at least a part of the third slope  204   a   3  overlaps with the second slope  204   a   2  when viewed in the direction of the rotational axis A. In addition, above (directly above) the third slope  204   a   3 , a cavity  204   a   4  and an abutment surface  204   a   5  (downstream end surface, contacted surface) are provided. The abutment surface  204   a   5  is an end surface on the downstream side in the rotational direction K, the end surface extending from the downstream end of the third slope  204   a   3  in the rotational direction L along the direction of the rotational axis A. The abutment surface  204   a   5  faces the downstream side in the rotational direction K. In part (c) of  FIG.  59   , the abutment surface  204   a   5  extends upward from the downstream end of the third slope  204   a   3  in the second horizontal direction hz 2 , and is an end surface on the downstream side in the first horizontal direction hz 1 . 
     Next, referring to part (c) of  FIG.  59   , the description will be made as to inclination angles of the first slope  204   a   1 , the second slope  204   a   2 , and the third slope  204   a   3  with respect to the rotational axis A. As shown in part (c) of  FIG.  59   , as the projecting portion  202   b  is viewed in the direction perpendicular to the rotational axis A (gravity direction), the inclination angles, with respect to the direction of the rotational axis A, of the first slope  204   a   1 , the second slope  204   a   2 , and the third slope  204   a   3  are α 1 , α 2 , and α 3 , respectively. In this embodiment, α 1 , α 2 , and α 3  are about 50 degrees, about 50 degrees, and about 40 degrees, respectively. It is preferable that α 1 , α 2 , and α 3  are all 30 degrees or more and 60 degrees or less. 
     In addition, in this embodiment, as the projecting portion  202   b  is viewed in the direction perpendicular to the rotational axis A, a length L 204   a   1  of the first slope  204   a   1  is about 2 mm, a length of the second slope  204   a   2  is about 3 mm, and a length L 204   a   3  of the third slope  204   a   3  is about 3.5 mm. It is preferable that the length L 204   a   2  is larger than the length L 204   a   1 , and the length L 204   a   3  is larger than the length L 204   a   2 . Further, a length H 204   a   1  from the projecting portion end surface  202   b   2  which is the lower end of the projecting portion  202   b  to the upper end of the first slope  204   a   1  is smaller than a length H 204   a   2  from the projecting portion end surface  202   b   2  to the upper end of the second slope  204   a   2 . 
     The first slope  204   a   1 , the second slope  204   a   2 , the third slope  204   a   3 , the cavity  204   a   4 , and the abutment surface  204   a   5  are exposed to the outside of the toner pack  220  so that they can be accessed by the rotation restricting mechanism  212  of the mounting portion  206 . They are structured so as to be exposed to the outside of the toner pack  220  in a state in which the toner pack  220  is in condition for being mounted to the mounting portion  206 . That is, in the case that a cap or a cover is provided to protect the nozzle  202  of the toner pack  220  and the shutter  203  on the pack side at the time of transportation, they are exposed when the cap or cover is removed. 
     Part (a) of  FIG.  62    is a cross-sectional view taken along a line X 209 -X 209  of the projecting portion  202   b  of part (a) of  FIG.  61   , and there are shown the third slope  204   a   3  of the first restriction releasing portion  204   a  and the third slope  204   b   3  of the second restriction releasing portion  204   b . It is understood that both the third slope  204   a   3  and the third slope  204   b   3  extend along the rotational direction of the pack-side shutter  203  (the circumferential direction of the imaginary circle VC centered on the rotational axis A). 
     Part (b) of  FIG.  62    is a view of the nozzle  202  viewed from the side where the projecting portion  202   b  can be seen in the direction of the rotational axis A. As shown in part (b) of  FIG.  62   , the restriction releasing portion  204  is placed outside the inner peripheral surface  202   b   1  and inside the discharge opening  202   a  in the radial direction r. The nozzle  202  is viewed in the direction of the rotational axis A, the first slope  204   a   1 , the second slope  204   a   2 , and the third slope  204   a   3  are preferably placed closer to the inner peripheral surface  202   b   1  than the discharge opening  202   a . Here, a distance from the rotational axis A to the inner peripheral surface  202   b   1  is r 1 , a distance from the rotational axis A to the outer end of the second slope  204   a   2  (second slope  204   b   2 ) is r 2 , and a distance from the rotational axis A to the discharge opening  202   a  r 3  preferably satisfy,
 
( r 2− r 1)/( r 3− r 1)&lt;0.3.
 
That is, as the nozzle  202  is viewed in the direction of the rotational axis A, a distance from the inner peripheral surface  202   b   1  to the first slope  204   a   1 , a distance from the inner peripheral surface  202   b   1  to the second slope  204   a   2 , and a distance from the inner peripheral surface  202   b   1  to the third slope  204   a   3  is preferably 30% or less of the distance from the inner peripheral surface  202   b   1  to the discharge opening  202   a.  
 
     As shown in  FIGS.  57  to  61   , the second restriction releasing portion  204   b  is provided with a first slope  204   b   1  (third downward surface), a second slope  204   b   2  (fourth downward surface), a third slope  204   b   3  (second upward surface), a cavity  204   b   4  (second cavity), and abutment surface  204   b   5  (second abutment surface, second downstream end surface, second contacted surface). Here, the second restriction releasing portion  204   b  has a 180-degree rotationally symmetric shape of the first restriction releasing portion  204   a  with respect to the rotational axis A, and it is provided on the opposite side of the restriction releasing portion  204   a  with respect to the rotational axis A in the radial direction r of the imaginary circle VC. In other words, the first slope  204   b   1 , the second slope  204   b   2 , the third slope  204   b   3 , the cavity  204   b   4 , and the abutment surface  204   b   5  have 180-degree rotational symmetry shapes, with respect to the rotational axis A, of, the first slope  204   a   1 , the second slope  204   a   2  third slope  204   a   3 , the cavity  204   a   4 , and the abutment surface  204   a   5 , respectively. That is, if the first slope  204   a   1 , the second slope  204   a   2 , the third slope  204   a   3 , the cavity  204   a   4 , and the abutment surface  204   a   5  are rotated 180 degrees around the rotational axis A, they become the first slope  204   b   1 , the second slope  204   b   2 , the third slope  204   b   3 , the cavity  204   b   4 , and the abutment surface  204   b   5 . Therefore, the detailed description of the second restriction releasing portion  204   b  will be omitted. 
     Here, the second slope  204   a   2  of the first restriction releasing portion  204   a  is not provided outside, in the radial direction r, of any region of the first slope  204   b   1  of the second restriction releasing portion  204   b . That is, the first slope  204   a   1  is provided at a position different from that of the second slope  204   b   2  in the circumferential direction of the imaginary circle VC. 
     As shown in part (a) of  FIG.  61    as viewed in a direction perpendicular to the rotational axis A (direction perpendicular to the arrow R direction), the projecting portion  202   b  is at a position between the surface  202   d   1  of the positioned portion  202   d  and the surface  202   d   2  in the arrow R direction. Therefore, in the direction of the arrow R, the positions of the first restriction releasing portion  204   a  and the second restriction releasing portion  204   b  are between the position of the surface  202   d   1  and the position of the surface  202   d   2  of the positioned portion  202   d . That is, in the direction of arrow R, the positions of the first slope  204   a   1 , the second slope  204   a   2 , and the third slope  204   a   3  are all between the position of the surface  202   d   1  and the position of the surface  202   d   2 . Viewed in the direction perpendicular to the rotational axis A, the positions of the first restriction releasing portion  204   a  and the second restriction releasing portion  204   b  overlap with the positions of the recess  202   e  in the arrow R direction. 
     In addition, as shown in part (a) of  FIG.  61   , the projecting portion  202   b  is inside the range of the width of the opening  203   a  of the pack-side shutter  203  in the arrow R direction as viewed in the direction perpendicular to the rotational axis A (radial direction r). 
     Further, in this embodiment, the projecting portion  202   b  is provided on the nozzle  202 , but it is not necessarily provided on the nozzle  202 . 
     Here, the projecting portion  202   b  of this embodiment is provided with two portions, namely a first restriction releasing portion  204   a  and a second restriction releasing portion  204   b , which are 180-degree rotationally symmetric with respect to the rotational axis A. However, the present invention is not limited to such an example. 
     Part (a) of  FIG.  196    and part (b) of  FIG.  196    are perspective views and bottom views of the neighborhood of the projecting portion  202   b  in which the first restriction releasing portion  204   a  is provided and the second restriction releasing portion  204   b  is not provided. 
     In part (c) of  FIG.  196    and part (d) of  FIG.  196    area perspective view and a bottom view of the neighborhood of the projecting portion  202   b  in which the second restriction releasing portion  204   b  has a shape of 190-degree rotational symmetry, with respect to the rotational axis A, of the first restriction releasing portion  204   a.    
     The structure may be such that only the first restriction releasing portion  204   a  including the first slope  204   a   1 , the second slope  204   a   2 , the third slope  204   a   3 , the cavity  204   a   4 , and the abutment surface  204   a   5  are provided, as shown in part (a) of  FIG.  196    and part (b) of  FIG.  196   . In addition, as shown in part (c) of  FIG.  196    and part (d) of  FIG.  196   , the second restriction releasing portion  204   b  may have a shape which is 190-degree rotationally symmetric with respect to the rotational axis A of the first restriction releasing portion  204   a . That is, the first slope  204   b   1 , the second slope  204   b   2 , the third slope  204   b   3 , the cavity  204   b   4 , and the abutment surface  204   b   5  may have shapes which are 190-degree rotationally symmetric of, the first slope  204   a   1 , the second slope  204   a   2 , the third slope  204   a   3 , the cavity  204   a   4 , and the abutment surface  204   a   5  with respect to the rotational axis A, respectively. With this structure, the angle α 204   ab   1  between the first slope  204   a   1  and the first slope  204   b   1  about the rotational axis is 190 degrees. The angle α 204   ab   2  between the second slope  204   a   2  and the second slope  204   b   2  about the rotational axis A is also 190 degrees. The second restriction releasing portion  204   b  preferably has a shape of 150 degrees or more and 210 degrees or less rotationally symmetric of the first restriction releasing portion  204   a  with respect to the rotational axis A. That is, the first slope  204   b   1 , the second slope  204   b   2 , the third slope  204   b   3 , the cavity  204   b   4 , and the abutment surface  204   b   5  preferably have shapes of 150 degrees or more and 210 degrees or less rotationally symmetric of the first slope  204   a   1 , the second slope  204   a   2 , the third slope  204   a   3 , the cavity  204   a   4  and the abutment surface  204   a   5  with respect to the rotational axis A, respectively. 
     (Mounting of Toner Pack to Mounting Portion) 
     Referring to  FIGS.  63  to  69   , the description will be made as to a mechanism for releasing the rotation restriction of the apparatus-side shutter  209  with the rotation restricting mechanism  212  described above by mounting the toner pack  220  on the mounting portion  206 . 
     Part (a) of  FIG.  63    and part (c) of  FIG.  63    are perspective views of the toner pack  220  and the mounting portion  206  while the toner pack  220  is being mounted on the mounting portion  206  and when the mounting is completed, respectively. Part (b) of  FIG.  63    is a perspective view of the toner pack  220  and the mounting portion  206  as viewed from a side different from that of part (a) of  FIG.  63   . Part (a) of  FIG.  64    a sectional view of the toner pack  220  and the mounting portion  206  taken along a line parallel to the rotational axis A (rotational axis B) in the state in which the toner pack  220  is further moved in the mounting direction from the state shown in part (a) of  FIG.  63   . Part (b) of  FIG.  64    is a cross-sectional view taken along a line X 210 -X 210  in part (a) of  FIG.  64   . Part (c) of  FIG.  64    is a cross-sectional view taken along a line X 211 -X 211  in part (a) of  FIG.  64   . Part (a) of  FIG.  65    to part (c) of  FIG.  65    are sectional views showing a process of mounting the toner pack  220  to the mounting portion  206 . Part (d) of  FIG.  65    to part (f) of  FIG.  65    are perspective views, which correspond to part (a) of  FIG.  65    to part (c) of  FIG.  65   , respectively but shows only the projecting portion  202   b , the releasing member  214 , and the restricting member  213 . Part (a) of  FIG.  66    and part (b) of  FIG.  66    are cross-sectional views showing a process of mounting the toner pack  220  to the mounting portion  206 , following the state shown in part (c) of  FIG.  65   . Part (c) of  FIG.  66    and part (d) of  FIG.  66    are perspective views which correspond to part (a) of  FIG.  66    and part (b) of  FIG.  66   , respectively, but shows only the projecting portion  202   b , the releasing member  214 , and the restricting member  213 . Part (a) of  FIG.  67    and part (b) of  FIG.  67    are perspective views illustrating a positional relationship between the releasing member  214  and the cover  210 . Part (c) of  FIG.  67    and part (d) of  FIG.  67    are illustrations of the releasing member  214  and the cover  210  in the states of part (a) of  FIG.  67    and part (b) of  FIG.  67   , as viewed in the direction (upper side) of the rotational axis A, respectively. Part (a) of  FIG.  68    is a cross-sectional view taken along the rotational axis A (rotational axis B) of the toner pack  220  and the mounting portion  206  in a state in which the mounting of the toner pack  220  has been completed on the mounting portion  206 . Part (b) of  FIG.  68    and part (c) of  FIG.  68    are a sectional view taken along a line X 213 -X 213  and a sectional view taken along a line X 212 -X 212  in part (a) of  FIG.  68   , respectively. 
     In  FIG.  64   , the cut surfaces of the shutter  203  on the pack side and the cover  210  is shaded for better illustration. In addition, in part (a) of  FIG.  65    to part (c) of  FIG.  65    and part (a) of  FIG.  66    and part (b) of  FIG.  66   , the pack side shutter  203 , the restricting member  213 , and the releasing member  214  are side views, and other members is shown in sectional view. Further, in  FIG.  68   , the cut surfaces of the cover  210 , the restricting member  213 , and the releasing member  214  are shaded for better illustration. 
     As shown in part (a) of  FIG.  63    and part (b) of  FIG.  63   , the toner pack  220  in which the pack-side shutter  203  is in the closed position is moved in the mounting direction M to the mounting portion  206  in which the apparatus-side shutter  209  is in the closed position. The user mounts the toner pack  220  on the mounting portion  206  by moving the toner pack  220  in the mounting direction M in a state of being oriented in the predetermined direction described above. The mounting direction M is the arrow N direction, that is, the vertical downward direction (gravity direction). Further, the mounting direction M is the direction of the rotational axis A (rotational axis B). 
     At this time, the toner pack  220  is mounted to the mounting portion  206  so that two positions are aligned in the rotational direction of the pack side shutter  203  (circumferential direction of the imaginary circle VC). The first is for the alignment between, as shown in part (a) of  FIG.  63    as viewed in the mounting direction M, the recess  202   e  of the nozzle  202  (opening  203   a  of the shutter  203  on the pack side) and the positioning portion  207   a  of the first frame  207 . The second is for the alignment between, as shown in part (b) of  FIG.  63   , the positions of the driven transmission portion  203   b  of the pack-side shutter  203  and the drive transmission portion  208   a  of the operating lever  208 . The structure is such that by aligning one of them, the other is aligned. 
     After aligning these positions, the toner pack  220  is moved in the mounting direction M and mounted to the mounting portion  206 , by which as shown in part (a) of  FIG.  64   , the small diameter portion  209   d   2  of the center boss  209   d  of the apparatus-side shutter  209  is inserted along the peripheral surface  202   b   1  inside the projecting portion  202   b  of the nozzle  202 . The inner peripheral surface  202   b   1  of the projecting portion  202   b  and the small diameter portion  209   d   2  of the center boss  209   d  are fitted (engaged). By this fitting, the position of the nozzle  202  in the radial direction r of the imaginary circle VC with respect to the apparatus-side shutter  209  below the nozzle  202  (downstream side in the mounting direction M) is determined. At this time, as shown in part (b) of  FIG.  64   , the drive transmission portion  208   a  (lever projection) of the operating lever  208  and the driven transmission portion  203   b  (rotary body recess portion) of the pack side shutter  203  are engaged with each other. In addition, the rib  203   e  is inserted into the slit  208   c  provided in the drive transmission portion  208   a . At the same time, as shown in part (c) of  FIG.  64   , the side surface  210   f  and the side surface  210   g  of the cover  210  guide the surface  202   e   1  and the surface  202   e   2  forming the recess  202   e  (nozzle recess) of the nozzle  202 . In addition, the driven transmission portion  203   b  (rotatable member recess portion) of the pack-side shutter  203  engages with the driven transmission portion  209   e  (shutter projection) of the apparatus-side shutter  209 . By this, the rotational axis A of the pack-side shutter  203  and the rotational axis B of the apparatus-side shutter  209  are made substantially coaxial. 
     The operating lever  208 , the pack side shutter  203 , and the apparatus-side shutter  209  are integrally rotatable about the rotational axis A (rotational axis B) relative to the first frame  207  (base frame  221 ) and the nozzle  202 . Specifically, when the operating lever  208  is rotated in the rotational direction D, the drive transmission portion  208   a  of the operating lever  208  pushes the surface  203   b   1  of the pack side shutter  203  to rotate the pack side shutter  203  in the rotational direction D. Thereafter, the surface  203   b   2  of the pack-side shutter  203  pushes the driven transmission portion  209   e  of the apparatus-side shutter  209 , and the apparatus-side shutter  209  is rotated in the rotational direction D. When the operating lever  208  is rotated in the rotational direction E, the drive transmission portion  208   a  of the operating lever  208  pushes the surface  203   b   2  of the pack-side shutter  203 , and the pack-side shutter  203  is rotated in the rotational direction E. Thereafter, the surface  203   b   1  of the pack-side shutter  203  pushes the driven transmission portion  209   e  of the apparatus-side shutter  209  to rotate the apparatus-side shutter  209  in the rotational direction E. Thus, the structure is such that in the case that the rotation restricting mechanism  212  described above is not provided, the apparatus-side shutter  209  is structured to be rotated by the operating lever  208  by way of the pack-side shutter  203 , and therefore, the apparatus-side shutter  209  can be rotated, regardless of the position of the operation lever. 
     Here, if the apparatus-side shutter  209  rotates in the rotational direction D from the closed position to the open position due to an erroneous operation by the user or vibration during transportation of the image forming apparatus  1 , the position of the driven transmission portion  209   e  of the apparatus-side shutter  209  in the rotational direction also shifts. Then, when the toner pack  220  is to be mounted on the mounting portion  206 , the result is as follows. When the toner pack  220  is further moved in the mounting direction M after the driven transmission portion  203   b  of the pack-side shutter  203  engages with the drive transmission portion  208   a  of the operating lever  208 , it is unable to engage with the driven transmission portion  209   e  of the apparatus-side shutter  209 . Therefore, the toner pack  220  cannot be moved to the mounting complete position relative to the mounting portion  206 . In order to prevent such a situation from occurring, the rotation restricting mechanism  212  restricts the rotation of the apparatus-side shutter  209 . 
     Next, referring to  FIGS.  65  to  67   , the details of the mechanism by which the rotation restricting mechanism  212  of the mounting portion  206  is released by mounting the toner pack  220  to the mounting portion  206  will be described.  FIGS.  65  and  66    are illustrations showing the process of mounting the toner pack  220  on the mounting portion  206  in chronological order. The second restriction releasing portion  204   b  functions in the same manner as the first restriction releasing portion  204   a , and therefore, the description thereof will be omitted. 
     At the time shown in part (a) of  FIG.  65    (part (d) of  FIG.  65   ), the first restriction releasing portion  204   a  of the nozzle  202  and the releasing claw  214   e  of the releasing member  214  are separated from each other. At this timing, as shown in part (a) of  FIG.  67    and part (c) of  FIG.  67   , the second guided surface  214   e   2  of the releasing claw  214   e  shown in  FIG.  47    is covered by the eave portion  210   n  of the cover  210  so as not to be exposed through the center hole  210   p  of the cover  210  as viewed in the direction of the rotational axis A. When the toner pack  220  is further moved in the direction of the arrow N (mounting direction M) from this position, the first slope  204   a   1  of the first restriction releasing portion  204   a  and the first guided surface  214   e   1  of the releasing claw  214   e  are brought into contact with each other, and a state shown in part (b) of  FIG.  65    (part (e) of  FIG.  65   ) results. When the toner pack  220  is further moved in the direction of the arrow N from this position, the releasing member  214  is rotated in the rotational direction D by the force F 204  received by the first guided surface  214   e   1  from the first slope  204   a   1 , against the urging force F 203  of the releasing spring  216  shown in  FIG.  50   . At this time, the first slope  204   a   1  of the first restriction releasing portion  204   a  functions as a guide surface which guides the first guided surface  214   e   1  of the releasing member  214  so that the first guided surface  214   e   1  moves along the first slope  204   a   1 . In other words, the first slope  204   a   1  guides the first guided surface  214   e   1  so that the releasing member  214  is rotated in the rotational direction D about the rotational axis A. Further, the first slope  204   a   1  of the first restriction releasing portion  204   a  also functions as a first force applying surface (first push surface) for applying (pushing) a force to the first guided surface  214   e   1 . The force F 204  includes a force component F 204   x  which rotates the releasing member  214  in the rotational direction D around the rotational axis B against the urging force of the releasing spring  216 . The releasing member  214  is rotated in the rotational direction D until the first guided surface  214   e   1  passes the downstream end, in the rotational direction D, of the first slope  204   a   1  in the rotational direction D. By the rotation of the releasing member  214  in the rotational direction D, the second guided surface  214   e   2  of the releasing claw  214   e  is exposed through the center hole  210   p  of the cover  210  as viewed in the direction of the rotational axis A, as shown in part (b) of  FIG.  67    (part (d) of  FIG.  67   ). That is, the first slope  204   a   1  has a function (preceding rotation function) of rotating the releasing member  214  to a position where at least the second guided surface  214   e   2  is exposed through the center hole  210   p  of the cover  210  as viewed in the direction of the rotational axis A. Although the first slope  204   a   1  of this embodiment is a slope, the present invention is not limited to such an example. It will suffice if it is a surface engageable with the first guided surface  214   e   1  to rotate the releasing member to 14 in the rotational direction D when the toner pack  220  is mounted on the mounting portion  206 . 
     When the toner pack  220  is further moved in the direction of arrow N from the positioned shown in part (b) of  FIG.  67    (part (d) of  FIG.  67   ), the second slope  204   a   2  of the first restriction releasing portion  204   a  is brought into contact with the second guided surface  214   e   2  of the releasing claw  214   e , with the result in the state shown in part (c) of  FIG.  65    (part (f) of  FIG.  65   ). In this state, when the toner pack  220  is moved in the direction of the arrow N, the releasing member  214  is rotated in the rotational direction D by a force F 205  received by the second guided surface  214   e   2  from the second slope  204   a   2 , against the force F 203  received from the releasing spring  216  shown in  FIG.  50   . At this time, the second slope  204   a   2  of the first restriction releasing portion  204   a  functions as a guide surface for guiding the second guided surface  214   e   2  so that the second guided surface  214   e   2  moves along the second slope  204   a   2 . In other words, the second slope  204   a   2  guides the second guided surface  214   e   2  of the releasing member  214  so that the releasing member  114  is rotated in the rotational direction D around the rotational axis A. Further, the second slope  204   a   2  of the first restriction releasing portion  204   a  also functions as a second force applying surface (second push surface) for applying (pushing) a force to the second guided surface  214   e   2 . The force F 205  includes a force component F 205   x  which rotates the releasing member  214  in the rotational direction D around the rotational axis B against the urging force of the releasing spring  216 . 
     The releasing member  214  is rotated in the rotational direction D until the second guided surface  214   e   2  passes the downstream end, in the rotational direction D, of the second slope  204   a   2  in the rotational direction D. The rotation of the releasing member  214  in the rotational direction D up to this point is the first step for releasing the rotation restriction described above. That is, this is a step of rotating the releasing member  214  in the rotational direction D against the urging force of the releasing spring  216  to the rise restriction release position (rise restriction release region) where the rise restricted surface  214   c  does not contact the rise restricting surface  210   e  of the cover  210  when the releasing member  214  is raised, as shown in part (b) of  FIG.  53   . In other words, It is a step of rotating the releasing member  214  against the urging force of the releasing spring  215  in the rotational direction D to the rise restriction release position where the rise restricted surface  214   c  does not overlap with the rise restricting surface  210   e  of the cover  210  as viewed in the direction of the rotational axis B. Although the second slope  204   a   2  of this embodiment is a slope, the present invention is not limited to such an example. It will suffice if it is engageable with the second guided surface  214   e   2  to rotate the releasing member  214  in the rotational direction D when the toner pack  220  is mounted to the mounting portion  206 . 
     After the first step, the third guided surface  214   e   3  of the releasing claw  214   e  rides up to the upstream end of the third slope  204   a   3  in the rotational direction E by way of the connecting portion  204   a   23  of the first restriction releasing portion  204   a . That is, the rotational direction of the releasing member  214  is switched from the rotational direction D to the rotational direction E at the connecting portion  204   a   23  of the first restriction releasing portion  204   a.    
     At this time, as shown in part (a) of  FIG.  66    (part (c) of  FIG.  66   ), the third guided surface  214   e   3  of the releasing claw  214   e  contacts the third slope  204   a   3  of the nozzle  202  and receives a force F 206  therefrom by the moment M 202  (urging force) of the releasing spring  216 . Then, by the force component F 206   y  in the direction of the arrow G of the force F 206 , the third guided surface  214   e   3  of the releasing member  214  moves in the direction in which the third slope  204   a   3  extends, while being guided by the third slope  204   a   3 . The third slope  204   a   3  guides, after the releasing member  214  is rotated in the rotational direction D by the first slope  204   a   1  and the second slope  204   a   2 , the third guided surface  214   e   3  so that the releasing member  214  is moved in the arrow G direction (upward) while being rotated in the rotational direction E. 
     The movement of the releasing member  214  in the arrow G direction is the second step for releasing the rotation restriction described above. In the second step, the restricting member  213  is moved in the arrow G direction by the releasing member  214 . In addition, the releasing member  214  is rotated in the rotational direction E until the contact surface  214   a  and the contact surface  214   f  of the releasing member  214  shown in part (d) of  FIG.  47    abut against the abutment surface  204   a   5  of the projecting portion  202   b . That is, in the releasing member  214 , the rotation in the rotational direction E is stopped by the contact surface  214   f  and the contact surface  214   f  abutting (contacting) the abutment surface  204   a   5  of the projecting portion  202   b . In this manner, the rotation restriction release operation of the rotation restricting mechanism  212  is completed in the state where the toner pack  220  is in the mounting complete position shown in part (b) of  FIG.  66    (part (d) of  FIG.  66   ) and  FIG.  68   . The cross-section taken along a line X 214 -X 214  in part (a) of  FIG.  68    is the same as that in part (b) of  FIG.  51   , and the rotation restriction of the apparatus-side shutter  209  is released. 
     As described above, by mounting the toner pack  220  on the mounting portion  206 , the rotation restriction of the apparatus-side shutter  209  by the rotation restricting mechanism  212  is released through the first step and the second step described above. Although the third slope  204   a   3  of this embodiment is a slope, the present invention is not limited to such an example. It will suffice if the surface it is a surface that engageable with the third guided surface  214   e   3  so that the releasing member  214  to move the releasing member  414  in the direction of arrow G (upward) when the toner pack  220  is mounted to the mounting portion  206 . In addition, in this embodiment, in the second step, the releasing member  214  is rotated in the rotational direction E, but the structure may be such that the releasing member  214  is not rotated in the rotational direction E. 
     As shown in part (a) of  FIG.  68   , the mounting completion position of the toner pack  220  is the position where the projecting portion end surface  202   b   2  of the projecting portion  202   b  of the nozzle  202  is in contact with the pack contact surface  209   g  of the apparatus-side shutter  209 . At this mounting complete position, the position of the toner pack  220  in the direction of the rotational axis A is determined with respect to the mounting portion  206 . In addition, the inner peripheral surface  202   b   1  of the projecting portion  202   b  of the nozzle  202  is fitted (engaged) with the small diameter portion  209   d   2  of the center boss  209   d  of the apparatus-side shutter  209 , By which the position thereof in the radial direction r of the imaginary circle VC on the downstream side of the mounting direction M. Further, as shown in part (c) of  FIG.  68    which is a cross-section taken along line X 212 -X 212  of part (a) of  FIG.  68   , three positions of the radial positioning portion  203   f  ( FIG.  57   ,  FIG.  59   ) of the pack side shutter  203  are in contact with the inner peripheral surface  209   h  ( FIG.  44   ) of the apparatus-side shutter  209 . By this, the positions of the nozzle  202  and the pack side shutter  203  (toner pack  220 ) in the radial direction r of the imaginary circle VC on the upstream side of the mounting direction M is determined. 
     On the other hand, as shown in part (b) of  FIG.  68    which is a cross-section taken along a line X 213 -X 213  of part (a) of  FIG.  68   , the positioning portion  207   a  of the first frame  207  is engaged with the positioned portion of the nozzle  202  having the surface  202   d   1  and the surface  202   d   2 . Therefore, the nozzle  202  is positioned with respect to the first frame  207  (base frame  221 ) in the arrow R direction of the surface  202   d   1  and the surface  202   d   2 . By this, the position of the nozzle  202  is determined with respect to the first frame  207  in the direction of the arrow R, and therefore, the operation of releasing the rotation restriction relative to the apparatus-side shutter  209  can be further stabilized. In this description, the magnitudes of the force F 204 , the force F 205 , and the force F 206  for operating the releasing member  214  are selected to be so large that the influences of gravity and frictional force can be ignored, and therefore, the description relating to the gravity and the frictional force are omitted. 
     By the mechanism described above, the rotation restriction of the apparatus-side shutter  209  by the rotation restricting mechanism  212  is released, and the apparatus-side shutter  209  becomes rotatable from the closed position to the release position. 
     Further, It is possible that when the contact surface  214   a  and the contact surface  214   f  of the releasing member  214  come into contact with the abutment surface  204   a   5 , the releasing member  214  is vigorously rotated by the moment M 202  to generate a light collision sound. In addition, the hand of the user holding the toner pack  220  can be made to feel the reaction. That is, the user can also recognize that the rotation restriction of the apparatus-side shutter  209  is released (mounting is completed) by the collision sound or the reaction. When the toner pack  220  is dismounted from the mounting portion  206 , the reverse process of  FIG.  65    is carried out, and the rotation of the apparatus-side shutter  209  is restricted by the rotation restricting mechanism  212  again. 
     (Operation of Operation Lever) 
     When the toner pack  220  is in the mounting complete position, as shown in part (b) of  FIG.  68   , the drive transmission portion  208   a  (lever projection) of the operating lever  208  and the driven transmission portion  203   b  (rotatable member recess) of the pack side shutter  203  are engaged with each other. In addition, as shown in part (c) of  FIG.  68   , the driven transmission portion  203   b  (rotatable member recess portion) of the pack-side shutter  203  is engaged with the driven transmission portion  209   e  (shutter projection) of the apparatus-side shutter  209 . That is, as described above, the structure is such that in the state where the toner pack  220  is mounted on the mounting portion  206 , the operating lever  208 , the pack-side shutter  203 , and the apparatus-side shutter  209  rotate integrally around the rotational axis A (rotational axis B). 
     Here, part (a) of  FIG.  69    is a perspective view of the toner pack  220  when the operating lever  208  is in the closed position, as viewed from above. Part (b) of  FIG.  69    is a perspective view of the toner pack  220  when the operating lever  208  is in the open position, as viewed from above. Part (c) of  FIG.  69    is an illustration showing a state in which the user loosens the accommodating portion  201  and replenishes the toner in the state of part (b) of  FIG.  69   . 
     As shown in part (a) of  FIG.  69    and part (b) of  FIG.  69    it is understood that when the operating portion  208   b  of the operating lever  208  is rotated in the rotational direction D after the mounting of the toner pack  220  on the mounting portion  206  is completed, the apparatus-side shutter  209  rotates from the closed position to the open position, and the accommodating portion  101  does not rotate even when the operating lever  208  for rotating the pack-side shutter  203  from the closed position to the open position is rotated. It is the pack side shutter  203  and the apparatus-side shutter  209  that rotate together with the operating lever  208 . 
     When the pack-side shutter  203  rotates from the closed position to the open position, a frictional force F 207  received by the nozzle  102  from the pack-side shutter  103  by way of the pack-side seal  105  is directed in the rotational direction K as shown in part (a) of  FIG.  57   . This is the same direction as the rotational direction D of the operating lever  108  in  FIG.  69   . The nozzle  202  receives the frictional force F 207  and may rotate in the rotational direction K by the amount of the play between the surfaces  202   d   1  and the surfaces  202   d   2  and the positioning portion  207   a  of the first frame  207 . The rotational direction of the nozzle  202  at this time is such that the third slope  204   a   3  of the first restriction releasing portion  204   a  approaches the releasing claw  214   e  of the releasing member  214 , and such that the third slope  204   b   3  of the second restriction releasing portion  204   b  approaches the releasing claw  214   e  of the releasing member  214 . That is, when the operating lever  208  is rotated to rotate the pack-side shutter  203  from the closed position to the open position, the restricting member  213  moves upward (in the U direction) together with the releasing member  214 . Then, the second restricting surface  213   c  of the restricting member  213  is separated upward from the restricted rib  209   c  of the apparatus-side shutter  209 , with the result that the margin for releasing the rotation restriction is increased. Therefore, it is possible to more stably maintain the state in which the rotation restriction is released with respect to the apparatus-side shutter  109 . 
     By the above operation, the toner pack  220  accommodating portion  201  and the toner accommodating chamber  36  are brought into contact with each other by way of the discharge opening  202   a , the receiving opening  209   a , and the apparatus-side opening  217   a.    
     Here, part (a) of  FIG.  70    is a sectional view of the toner pack  220  and the mounting portion  206  when both the apparatus-side shutter  209  and the pack-side shutter  203  are in the closed positions. Part (b) of  FIG.  70    is a cross-sectional view of the toner pack  220  and the mounting portion  206  when both the apparatus-side shutter  209  and the pack-side shutter  203  are in the open positions. 
     In part (a) of  FIG.  70   , the discharge opening  202   a  of the nozzle  202  is closed by the pack side shutter  203 , the pack side seal  205 , and the apparatus-side shutter  209 , so that the toner in the accommodating portion  201  cannot reach the apparatus-side opening  217   a  of the second frame  217 . On the other hand, in part (b) of  FIG.  70   , the discharge opening  202   a  of the nozzle  202  is opened by the movement of the pack-side shutter  203 , the pack-side seal  205 , and the apparatus-side shutter  209 . As shown in part (c) of  FIG.  69   , as the accommodating portion  201  is compressed by the user, the toner in the accommodating portion  201  is discharged to the outside of the toner pack  220  together with the air from the discharge opening  202   a . A part of the air discharged from the discharge opening  202   a  passes through the first filter  218  and the second filter to be discharged to the outside of the mounting portion  206 . The toner is replenished into the toner accommodating chamber  36  of the developer container  32  through the apparatus-side opening  217   a  of the second frame  217 . 
     Modified Example 1 
     Next, referring to  FIGS.  72  to  78   , another structure will be described. The same points as those of the above-described examples will be omitted. In particular, of the elements disclosed in this modified example, those corresponding to the members described in Embodiment 2 are assigned the like names as the members of Embodiment 2, and the points different from those of Embodiment 2 will be described. 
     In this embodiment, the projecting portion  202   b  of the nozzle  202  is integrally formed with the nozzle  202 . In this modified example, the projecting portion of Embodiment 2 is an attachment which is a component different from the nozzle. The attachment is an attachment to be mounted to the image forming apparatus  1 . And, a mounting kit includes the attachment and a toner pack having no projection. The structure of the attachment will be described below. 
       FIG.  72    is a perspective view of the attachment  2102 A of this modified example. Part (a) of  FIG.  72    and part (b) of  FIG.  72    are perspective views of the attachment  2102 A as viewed from points different from each other, and part (c) of  FIG.  72    is a perspective view of the attachment as viewed from a point different that of part (b) of  FIG.  72   .  FIG.  76    is a perspective view of the toner pack  2120  having no projection. Part (a) of  FIG.  77    is a side view of a state in which the toner pack  2120  is mounted on the image forming apparatus  1 , and part (b) of  FIG.  77    is a sectional view taken along a line X 2103 -X 2103  in part (a) of  FIG.  77   .  FIG.  78    is a perspective view of the attachment  21102 A having a shape different from that of the attachment  2102 A of this modified example. 
     When the attachment  2102 A is mounted to the mounting portion  206 , the rotation restriction by the rotation restricting mechanism  212  can be released even if the mounting is started from any phase in the circumferential direction of the imaginary circle VC to the mounting portion  206 . The structure of this modified example will be described below. 
     As shown in part (a) of  FIG.  72   , the attachment  2102 A has a generally cylindrical shape, and includes a cylindrical portion  2102 Aa and a projecting portion  2102 Ab provided in the order named from the first end side of the first direction D 1 . The cylindrical portion  2102 Aa and the projecting portion  2102 Ab have inner peripheral surfaces  2102 Ab 1 . The inner peripheral surface  2102 Ab 1  of this modified example is a cylindrical surface having a central axis A. The inner peripheral surface  2102 Ab 1  does not necessarily have to be a cylindrical surface as in Embodiment 2. The projecting portion  2102 Ab has the same structure as the projecting portion  202   b  of the nozzle  202  of Embodiment 2 shown in part (b) of  FIG.  59    and part (c) of  FIG.  59    and  FIG.  60   . The first restriction releasing portion  2104   a  (first projection) and the second restriction releasing portion  2104   b  (second projection) of the projecting portion  2102 Ab in the present modified example have the same structure as the first restriction releasing portion  204   a  and the second restriction releasing portion  204   b  of Embodiment 2, respectively, and they are structured with the central axis A of the inner peripheral surface  2102 Ab 1  as the reference. That is, the first slope  2104   a   1 , the second slope  2104   a   2 , the third slope  2104   a   3 , the cavity  2104   a   4 , and the abutment surface  2104   a   5  of the projecting portion  2102 Ab have the same structures as the first slope  204   a   1 , the second slope  204   a   2 , and the third slope  204   a   3 , the cavity  204   a   4 , and the abutment surface  204   a   5 , respectively, and are structured with the central axis A of the inner peripheral surface  2102 Ab 1  as the reference. The second restriction releasing portion  2104   b  has a shape that is 180 degrees rotationally symmetric with respect to the rotational axis A of the first restriction releasing portion  2104   a , and therefore, the description thereof will be omitted. 
     The cylindrical portion  2102 Aa and the projecting portion  2102 Ab are coaxially with the central axis A. The cylindrical portion  2102 Aa is provided with an end surface  2102 Ax perpendicular to the central axis A on the first end side in the first direction D 1 . Here, the attachment  2102 A has a shape that is 180-degree rotationally symmetric with respect to the central axis A, and therefore, only one side will be described. The cylindrical portion  2102 Aa is provided with projections  2102 Am and  2102 An which are on the second end side in the first direction D 1  and which project in the radial direction r of the imaginary circle VC centered on the central axis A. The projections  2102 Am and  2102 An are placed in the projecting portion  2102 Ab in the rotational direction about the central axis A, and a projection  2102 An is provided on the downstream side in the rotational direction E of the projection  2102 Am. In addition, on the upstream side of the projection  2102 Am in the rotational direction E, an end surface  2102 Ar parallel to the central axis A and crossing the rotational direction E is provided. Further, on the downstream side of the projection  2102 An in the rotational direction E, an end surface  2102 As parallel to the central axis A and crossing the rotational direction E is provided. The end surface  2102 As is provided adjacent to the restriction releasing portion  2104   b  of the projecting portion  2102 Ab, and the end surface  2102 As is on the downstream side, in the rotational direction E, of the surface  2104   s  which is a surface of the restriction releasing portion  2104   b  facing the downstream side in the rotational direction E. Here, the surface  2104   s  is a flat surface which is parallel to the central axis A and crossing the rotational direction about the central axis A. The end surface  2102 As and the surface  2104   s  are smoothly connected in the first direction D 1  by a slope  2102 Aw. 
     End surfaces  2102 At and  2102 Au on the second end side, in the first direction D 1 , of the projections  2102 Am and  2102 An are flat surfaces perpendicular to the central axis A, are placed at the same position in the first direction D 1  and are located on the first end side in the first direction D 1  from the projection end surface  2102 Ab 2  of the projecting portion  2102 Ab. 
     (Mounting of Attachment) 
     The attachment  2102 A is mounted to the mounting portion  206  of the image forming apparatus  1 . The details will be described below. Referring to  FIGS.  73 ,  74  and  75   , a method (usage method) of mounting the attachment  2102 A to the image forming apparatus  1  will be described. 
       FIG.  73    is a schematic view illustrating parts of the cover  210 , the restricting member  213 , the releasing member  214 , and the apparatus-side shutter  209  relating to a mounting operation of the attachment  2102 A to the mounting portion  206 , with the other portions omitted. Part (a) of  FIG.  73    is a top view, and part (b) of  FIG.  73    is a sectional view taken along the line X 2101 -X 2101  in part (a) of  FIG.  73   .  FIGS.  74  and  75    are sectional views illustrating a mounting process. In addition, it is a Figure illustrating the cover  210 , the restricting member  213 , and the releasing member  214 , which are relating to mounting of the attachment  2102 A to the image forming apparatus  1 , With the other portions omitted. That is,  FIGS.  74  and  75    are illustrations in which the apparatus-side shutter  209  is omitted from  FIG.  73   . Part (a) of  FIG.  74   , part (b) of  FIG.  74   , part (a) of  FIG.  75    and part (b) of  FIG.  75    are sectional views, taken along a line X 2101 -X 2101  in part (a) of  FIG.  73   , illustrating the process of mounting the attachment  2102 A to the image forming apparatus  1 . In addition, part (c) of  FIG.  74   , part (d) of  FIG.  74   , part (c) of  FIG.  75   , and part (d) of  FIG.  75    are cross-sectional views taken along a line X 2102 -X 2102  in part (b) of  FIG.  73   , corresponding to the states shown in part (a) of  FIG.  74   , part (b) of  FIG.  74   , part (a) of  FIG.  75   , and part (b) of  FIG.  75   , respectively. 
     As shown in part (b) of  FIG.  73   , the user mounts the attachment  2102 A to the mounting portion  206  by moving it downward (arrow N) with the projecting portion  2102 Ab facing downward (gravity direction) and with the central axis A directed approximately in a predetermined direction facing the gravity direction. At this time, the mounting movement is effected so that the inner peripheral surface  2102 Ab 1  (recess) of the attachment  2102 A is engaged (fitted) with the center boss  209   d  (positioning shaft, shaft portion) of the apparatus-side shutter  209 . By engaging (fitting) the inner peripheral surface  2102 Ab 1  of the attachment  2102 A with the center boss  209   d , the attachment  2102 A is positioned in the radial direction about the rotational axis B with respect to the apparatus-side shutter  209 , and the central axis A of the attachment  2102 A becomes coaxial with the rotational axis B of the mounting portion  206 . Further, the user pushes the attachment  2102 A in the direction of arrow N while rotating it in the rotational direction E. 
     As shown in part (a) of  FIG.  74    and part (c) of  FIG.  74   , when the attachment  2102 A is mounted in the direction of the arrow N, the inner peripheral surface  2102 Ab  1  of the attachment  2102 A engages with the center boss  209   d  of the apparatus-side shutter  209 , and then the projecting portion end surface  2102 Ab 2  of the attachment  2102 A abuts to the upper surface  210   i  of the cover  210 . Further, as shown in part (b) of  FIG.  74    and part (d) of  FIG.  74   , the user pushes the attachment  2102 A in the direction of the arrow N while rotating the attachment  2102 A in the rotational direction E, and the projection end surface  2102 Ab 2  of the attachment  2102 A abuts to the end surface  214   h  of the releasing member  214  placed on the second end side in the first direction D 1 . As shown in part (a) of  FIG.  75    and part (c) of  FIG.  75   , when the user further rotates the attachment  2102 A in the rotational direction E, the first slope  2104   a   1  of the attachment  2102 A comes into contact with the guided surface  214   e   1  of the releasing member  214 . In this manner, the releasing member  214  is rotated in the rotational direction D while being guided by the first slope  2104   a   1  by application of a force from the first slope  214   a   1  as in Embodiment 2. Further, By the user rotating the attachment  2102 A in the rotational direction E, as shown in part (c) of  FIG.  75   , the surface  2104   s  abuts to the eave portion  210   n  of the cover  210  in the rotational direction E, and the rotation of the attachment  2102 A is stopped thereby. 
     When the user further pushes the attachment  2102 A in the direction of the arrow N from the state shown in part (a) of  FIG.  75    and part (c) of  FIG.  75   , the slope  2102 Aw (see part (b) of  FIG.  72   ) abuts to the eave portion  210   n  of the cover  210 , by which an attachment  2102 A slightly rotates in the rotational direction D along the slope  2102 Aw relative to the cover  210 . Further, as shown in part (b) of  FIG.  75    and part (d) of  FIG.  75   , when the user pushes the attachment  2102 A in the direction of the arrow N, the end surface  2102 As and the end surface  2102 Ar are sandwiched in the rotational direction centered on the central axis A, between the eave portion  210   n  and the surface  210   r  facing the eave portion  210   n  in the rotational direction centered on the central axis A, and it is tightly fitted. Here, the surface  210   r  is parallel to the central axis A and process with the rotational direction E about the central axis A. Further, when the attachment  2102 A is pushed in the arrow N direction by the user, the projecting portion end surface  2102 Ab 2  abuts to the pack contact surface  209   g , and the movement of the attachment  2102 A in the arrow N direction is stopped (see part (b) of  FIG.  77   ) 
     The operation of the releasing member  214  accompanying the attachment of the above attachment  2102 A to the mounting portion  206  will be described. 
     First, as shown in part (a) of  FIG.  75   , the releasing member  214  is rotated in the rotational direction D while being guided by the first slope  2104   a   1 . 
     Further, the attachment  2102 A moves in the direction of the arrow N, and the releasing member  214  rotated in the rotational direction D by the force F 204  (see  FIG.  65   ) which the first guided surface  214   e   1  receives from the first slope  2104   a   1 , against the urging force F 203  of the spring  216  shown in  FIG.  50   . 
     The releasing member  214  is rotated in the rotational direction D until the first guided surface  214   e   1  passes the downstream end, in the rotational direction D, of the first slope  2104   a   1  in the rotational direction D. 
     The attachment  2102 A is further moved in the direction of the arrow N, the second slope  2104   a   2  of the first restriction releasing portion  2104   a  abuts to the second guided surface  214   e   2  of the releasing claw  214   e , with the results of the state shown in part (c) of  FIG.  65    (part (f) of  FIG.  65   ) is reached. In this state, when the attachment  2102 A is moved in the direction of the arrow N, the releasing member  214  is rotated in the rotational direction D by the force F 205  received by the second guided surface  214   e   2  from the second slope  2104   a   2 , against the urging force F 203  applied by the releasing spring  216  of the releasing spring  216 . 
     The releasing member  214  is rotated in the rotational direction D until the second guided surface  214   e   2  passes the downstream end, in the rotational direction D, of the second slope  2104   a   2  in the rotational direction D. The rotation of the releasing member  214  in the rotational direction D up to this point is the first step for releasing the rotation restriction. 
     The subsequent operations of the releasing member  214  are the same as those in Embodiment 2, and therefore, the description thereof will be omitted. 
     As in Embodiment 2, the rotation restriction by the rotation restricting mechanism  212  of the image forming apparatus  1  is released, and the apparatus-side shutter  209  becomes in a rotatable state. Here, the attachment  2102 A is started to be mounted to the mounting portion  206  at any phase in the rotational direction about the central axis A. The release operation is started from which state described above depends on the phase at which the mounting is started, but the rotation restriction by the rotation restricting mechanism  212  can be released regardless of the state at which the release operation is started. 
     After the attachment  2102 A is mounted to the mounting portion  206 , the toner pack  2120  having no projection as shown in  FIG.  76    is mounted to the mounting portion  206  of the image forming apparatus  1  as shown in  FIG.  77   . As shown in  FIG.  76   , since the toner pack  2120  of this modified example has the same shape as that of Embodiment 2 except for the nozzle  202  shown in Embodiment 2, the description other than the nozzle  2102 B will be omitted. 
     In the nozzle  2102 B of this modified example, a cylindrical recess portion  2102 Ba is provided coaxially with the central axis A on the first end side in the first direction D 1 . A surface  2102 Bb perpendicular to the central axis A is provided on the second end side of the recess  2102 Ba in the first direction D 1 . As shown in part (b) of  FIG.  77   , the toner pack  2120  is mounted to the mounting portion  206  in the same manner as in Embodiment 2, and the through hole  203   h  which is on first end side of the pack side shutter  203  in the first direction D 1  and which is coaxial with the central axis A the attachment  2102 A engages with the cylindrical portion  2102 Aa. It will suffice if the through hole  203   h  is larger than the cylindrical portion  2102 Aa. Thereafter, similarly, the recess  2102 Ba of the nozzle  2102 B engages (fits) with the cylindrical portion  2102 Aa of the attachment  2102 A and the position of the nozzle  2102 B in the radial direction relative to the attachment  2102 A is determined. Further, the surface  2102 Bb of the nozzle  2102 B abuts to the end surface  2102 Ax of the attachment  2102 A, so that the mounting in the arrow N direction is completed. Thereafter, the toner in the accommodating portion  2101  is replenished into the toner accommodating chamber  36  of the developer container  32  in the same manner as in Embodiment 2. After use, the toner pack  2120  is removed in the same manner as in Embodiment 2, and then the attachment  2102 A is removed against the tightening fitting force of the cover  210 . 
     A mounting kit may include the attachment  2102 A and the toner pack  2120  having no projection are set. 
     The method of using the mounting kit has two steps. The first step is a step of moving the attachment  2102 A downward along the central axis in a state of being oriented in the predetermined direction described above to mount the attachment  2102 A to the mounting portion. The second step is a step after the first step, and is a step of mounting the toner pack  2120  on the mounting portion. By the first step, the rotation restriction by the rotation restricting mechanism  212  of the apparatus-side shutter  209  is released. By the second step, the toner pack  2120  is mounted to the mounting portion  206  to which the attachment  2102 A is mounted. 
     By transporting the toner pack in the form of the mounting kit, the packaging size of the toner pack  2120  in the central axis A direction can be reduced as compared with the structure of Embodiment 2. When the toner pack  2120  is used, the rotation restriction by the rotation restricting mechanism  212  of the apparatus-side shutter  209  can be released as in the other embodiments, by the user mounting the attachment  2102 A to the image forming apparatus  1  in advance. When the toner pack  2120  is used, the rotation restriction by the rotation restricting mechanism  212  of the apparatus-side shutter  209  can be released as in the other embodiments, by the use of mounting the attachment  2102 A to the toner pack  2120  in advance. 
     Next, the attachment  21102 A having a structure simpler than that of the attachment  2102 A will be described. 
     The attachment  2102 A has been described as having the structure with which the rotation restriction by the rotation restricting mechanism  212  can be released regardless of the beginning phase, in the circumferential direction of the imaginary circle VC, of the mounting of the attachment  2102 A to the mounting portion  206 . However, it is also possible to employ a simpler structure such as the attachment  21102 A, with which the user aligns and mounts the mounting portion  206  so as to match the phase of the mounting portion  206  around the central axis A. 
     As shown in  FIG.  78   , the attachment  21102 A has a generically cylindrical shape, and a cylindrical portion  21102 Aa and a projecting portion  21102 Ab (projecting portion) are provided in the order named in the first direction D 1 . In the following, in the first direction D 1 , the cylindrical portion  21102  side of the attachment  21102 A is referred to as the first end portion and the projecting portion side is referred to as the second end portion. 
     The cylindrical portion  21102 Aa has an inner peripheral surface  21102 Ab 1 . The inner peripheral surface  21102 Ab 1  of this modified example is a cylindrical surface having a central axis A. As shown in  FIG.  71    of Embodiment 2, the inner peripheral surface  21102 Ab 1  does not have to be a cylindrical surface as long as the central axis A can be defined. The projecting portion  21102 Ab has the same structure as the projecting portion  202   b  of the nozzle  202  of Embodiment 2 shown in part (b) of  FIG.  59    and part (c) of  FIGS.  59  and  60   . The first restriction releasing portion  21104   a  (first projection) and the second restriction releasing portion  21104   b  (second projection) of the projecting portion  21102 Ab have the same structures as the first restriction releasing portion  204   a  and the second restriction releasing portion  204   b  of Embodiment 2, respectively, and it is structured with respect to the central axis A of the inner peripheral surface  21102 Ab  1 . That is, the first slope  21104   a   1 , the second slope  21104   a   2 , the third slope  21104   a   3 , the cavity  21104   a   4 , and the abutment surface  21104   a   5  of the projecting portion  21102 Ab are the first slope  204   a   1  have the same structures as the first slope  204   a   1 , the second slope  204   a   2 , the third slope  204   a   3 , the cavity  204   a   4 , and the abutment surface  204   a   5 , respectively, and they are structured with reference to the central axis A of the inner peripheral surface  2102 Ab 1 . The second restriction releasing portion  21104   b  has a shape which is 180 degrees rotationally symmetric with respect to the rotational axis A of the first restriction releasing portion  21104   a , and therefore, the description thereof will be omitted. 
     On the first end side of the cylindrical portion  21102 Aa in the first direction D 1 , a triangular marking portion  21102 Ac recessed toward the second end side in the first direction D 1  is provided at a position away from the central axis A. Further, as shown in  FIG.  76   , In the toner pack  2120  of this modified example, the nozzle  2102 B is provided with a cylindrical recess portion  2102 Ba in order to avoid interference with the attachment  21102 A already mounted on the mounting portion  206 , when the toner pack  2120  is mounted on the mounting portion  206 . Other structures will be described hereinafter. 
     As shown in  FIG.  77   , the user mounts the attachment  21102 A to the mounting portion  206  so that the marking portion  21102 Ac faces the operating portion  208   b  of the operation lever  208  shown in  FIG.  67    in the circumferential direction of the imaginary circle VC centered on the central axis A. This is because when the attachment  21102 A is mounted on the mounting portion  206 , it is necessary to align the phase around the central axis A between the projecting portion  21102 Ab and the mounting portion  206 . The operation for releasing the rotation restriction of the mounting portion  206  is the same as the above-described structure, and therefore, the description thereof will be omitted. 
     Thereafter, the user mounts the toner pack  2120  on the mounting portion  206 . Then, as in Embodiment 2, the rotation restriction by the rotation restricting mechanism  212  of the apparatus-side shutter  209  is released, and the toner can be replenished from the toner pack  2120  into the toner accommodating chamber  36  of the developer container  32 . 
     Or, the structure may be such that when using the toner pack  2120 , the attachment  21102 A is mounted to the toner pack  2120  in advance. By doing so, similarly to embodiment 2, the rotation restriction by the rotation restricting mechanism  212  of the apparatus-side shutter  209  can be released by the attachment operation of the toner pack  2120  to the mounting portion  206 . In this case, the attachment  21102 A is mounted to the lower, when the toner pack  2120  is oriented in a predetermined direction, end of the nozzle  2102 B in a predetermined rotation phase. By doing so, the phase adjustment at the time of mounting on the mounting portion  206  is unnecessary. 
     The structure of the projecting portion  2102 Ab in this modified example can be used not only for the projecting portion  202   b  of embodiment 2 but also for modified examples of Embodiment 2. 
     Modified Example 2 
     Next, referring to  FIGS.  79  to  87   , another structure will be described. The same points as those of the above-described embodiments and modified examples will be omitted. In particular, of the elements disclosed in this modified example, those corresponding to the members described in Embodiment 2 and Modified Example 1 of Embodiment 2 are assigned the like names as the members of Embodiment 2 and Modified Example 1 of Embodiment 2, and only the points different from those of Embodiment 2 and Modified Example 1 of Embodiment 2 will be described. 
     In Modified Example 1 of Embodiment 2, the mounting kit comprising the attachment  2102  including the projecting portion  2102 Ab, and a toner pack  2120  including the pack side shutter  203  and the accommodating portion  2101  has been described. In the now describing modified example, a structure in which the attachment has a shutter (rotatable member) will be described. That is, this modified example relates to a mounting kit comprising an attachment including a shutter and a projecting member having a projecting portion, and a toner pack. Although with such a mounting kit, it is possible to release the rotation restriction by the rotation restricting mechanism  212  of the apparatus-side shutter  209  and replenish the toner from the toner pack into the toner accommodating chamber  36  of the developer container  32 , as in Embodiment 2. 
     In this modified example, referring to  FIGS.  79 ,  80 ,  81  and  82   , the attachment  2230  including the projecting member  2202  and the shutter  2203  will be described. Part (a) of  FIG.  79    and part (b) of  FIG.  79    are a perspective view and a side view of the attachment  2230  of this modified example, respectively. Parts (a) and (b) of  FIG.  80    are perspective views of the shutter  2203  as viewed in different directions, respectively.  FIG.  81    is a perspective view of the projecting member  2202 . 
     As shown in part (a) of  FIG.  79   , the attachment  2230  of this modified example has a shutter (rotatable member)  2203  and a projecting member  2202  (projecting member). The shutter  2203  and the projecting member  2202  are arranged in the first direction D 1 . 
     Referring to  FIGS.  80  and  81   , the structure of each component will be described in detail. Here, the shutter  2203  of this modified example has the same shape as the pack-side shutter  203  of Embodiment 2 except for the portion to which the projecting member  2202  is mounted, and therefore, only the mounting portion of the projecting member  2202  will be described. The shutter  2203  is mounted to the projecting member  2202  rotatably about the central axis A as the rotational axis. Further, in the following, in the first direction D 1 , the shutter  2203  side is referred to as the first end portion and the projecting member  2202  side is referred to as the second end portion. 
     As shown in part (a) of  FIG.  80   , the shutter  2203  has a substantially cylindrical shape centered on the central axis A, and has a hollow cylindrical portion  2203   a  substantially coaxial with the central axis A on the second end side in the first direction D 1 . For the shutter  2203 , in the inside of hollow cylindrical portion  2203   a  centered on the central axis A, there are provided a cylindrical surface  2203   b  and a through hole  2203   c  having a diameter smaller than that of the cylindrical surface  2203   b , substantially coaxially with the axis A, in this order from the first end side in the first direction D 1 . The hollow cylindrical portion  2203   a  is provided with two snap-fit portions  2203   k  at the positions 180-degree rotational symmetry about the central axis A. The snap-fit portion  2203   k  is provided so as to project from the hollow cylindrical portion  2203   a  toward the first end portion in the first direction D 1 , and is provided with a claw portion  2203   m  projecting toward the central axis A side. The claw portion  2203   m  faces the second end portion side in the first direction D 1  and has a support surface  2203   n  substantially perpendicular to the central axis A. In addition, the surface  2203   r  is on the central axis A side of the claw portion  2203   m . The surface  2203   r  is arranged inside the cylindrical surface  2203   b  with respect to the central axis A. The cylindrical surface  2203   b  and the through hole  2203   c  are connected by a surface  2203   d  substantially perpendicular to the central axis A. As shown in part (b) of  FIG.  80   , the surface  2203   d  is provided with two recesses  2203   e  recessed toward the second end side in the first direction D 1  at the position 180 degrees symmetric positions about the central axis A. The recess portion  2203   e  has a sector recess shape centered on the central axis A, the side thereof close to the central axis A is in fluid communication with the through hole  2203   c , and the side thereof far from the central axis A has a smaller radius than the cylindrical surface  2203   b . Further, the angle of the sector shape about the central axis A is about 90 degrees. The recess portion  2203   e  is provided with a surface  2203   f  which crosses the rotational direction D on the upstream side in the rotational direction D and a surface  2203   g  which substantially crosses the rotational direction D on the downstream side in the rotational direction D. A surface  2203   h  substantially perpendicular to the central axis A is provided on the second end, in the first direction D 1 , side (bottom surface of the recess) of the recess portion  2203   e . As shown in part (b) of  FIG.  83   , the shutter  2203  further is provided with a driven transmission portion  2203   u  (rotatable member recess) recessed inward in the radial direction r on a side peripheral portion centered on the central axis A. In addition, as viewed in the direction of the central axis A, a shutter opening  2203   t  (rotatable member opening) is provided on the side opposite from the side provided with the driven transmission portion  2203   s  with respect to the central axis A. The driven transmission portion  2203   u  has the same structure and function as the driven transmission portion  203   b  shown in part (b) of  FIG.  57    and part (a) of  FIG.  59    of Embodiment 2. The shutter opening  2203   t  has the same structure as the opening  203   a  shown in part (a) of  FIG.  57    and part (a) of  FIG.  61    of Embodiment 2. 
     As shown in  FIG.  81   , the projecting member  2202  has a substantially cylindrical shape centered on the central axis A, and is provided with a first cylindrical portion  2202   a , a second cylindrical portion  2202   c  having a diameter smaller than that of the cylindrical portion  2202   a  and a substantially cylindrical projecting portion  2202   b  (projecting portion) in this order from the first end portion side in the first direction D 1 . Central axes of the first cylindrical portion  2202   a  and the second cylindrical portion  2202   c  of the projecting member  2202  are coincident with the central axis A. In addition, the projecting member  2202  has an inner peripheral surface  2202   b   1  (guide inner peripheral surface, positioning inner peripheral surface) centered on the central axis A. The inner peripheral surface  2202   b   1  of this modified example is a cylindrical surface having the central axis A. The inner peripheral surface  2202   b   1  is preferably a cylindrical surface or a surface for which a central axis A can be defined as shown in  FIG.  71    of Embodiment 2. 
     The projecting portion  2202   b  has the same shape as the projecting portion  202   b  of Embodiment 2 shown in part (b) of  FIG.  59   , part (c) of  FIG.  59    and  FIG.  60   . The first restriction releasing portion  2204   a  (first projection) and the second restriction releasing portion  2204   b  (second projection) of the projecting member  2202 Ab of this modified example have the same structures as the first restriction releasing portion  204   a  and the second restriction releasing portion  204   b  of Embodiment 2, respectively, and is structured with reference to the central axis A as the rotational axis of the shutter  2203 . That is, the first slope  2204   a   1 , the second slope  2204   a   2 , the third slope  2204   a   3 , the cavity  2204   a   4 , and the abutment surface  2204   a   5  of the projecting member  2202 Ab have the same structures as the first slope  204   a   1 , the second slope  204   a   2 , the third slope  204   a   3 , the cavity  204   a   4  and the abutment surface  204   a   5  of Embodiment 2, respectively, and they are structured with reference to the central axis A of the inner peripheral surface  2102 Ab  1 . The second restriction releasing portion  2204   b  has a shape which is 180 degrees rotationally symmetric with respect to the rotational axis A of the first restriction releasing portion  2204   a , and therefore, the description thereof will be omitted. 
     Two projections  2202   e  projecting from the first cylindrical portion  2202   a  toward the second end portion in the first direction D 1  are provided at two positions 180-degree rotational symmetry about the central axis A. The projecting member  2202   e  is provided inside an outer shape of the first cylindrical portion  2202   a  in the radial direction r of the imaginary circle VC centered on the central axis A, and the central axis A side thereof is connected to the second cylindrical portion  2202   c . The projections  2202   e  are each provided with an end surface  2202   f  which crosses the rotational direction D on the upstream side in the rotational direction D and an end surface  2202   g  which crosses the rotational direction D on the downstream side in the rotational direction D. 
     Further, as shown in part (b) of  FIG.  79   , the projecting member  2202   b  is inside the width of the shutter opening  2203   t  in a direction perpendicular to the rotational axis A, as viewed in a direction perpendicular to the rotational axis A so that the shutter opening  2203   t  of the shutter  2203  faces the front. 
     (Assembling) 
     Next, referring to  FIGS.  82  and  83   , the assembly of the shutter  2203  and the projecting member  2202  will be described.  FIG.  82    is an exploded perspective view of the attachment  2230  of this modified example. Part (a) of  FIG.  83    and part (b) of  FIG.  83    are sectional views taken along lines X 2201 -X 2201  and X 2202 -X 2202 , respectively in  FIG.  79    at the time when the projecting member  2202  is placed at the first position relative to the shutter  2203 . 
     As shown in  FIG.  82   , the projecting member  2202  is provided substantially coaxially with the central axis A from the first end side toward the shutter  2203  in the first direction D 1 . The projecting member  2202  is mounted to the shutter  2203  while pushing the two snap-fit portions  2203   k  of the shutter  2203  in directions away from each other. Thereafter, the projecting member  2202  is supported by the shutter  2203  so that the second cylindrical portion  2202   c  is fitted in the through hole  2203   c  of the shutter  2203 . Further, the outer circumference of the first cylindrical portion  2202   a  of the projecting member  2202  is fitted to the cylindrical surface  2203   b  of the shutter  2203  with slight tightness. 
     As shown in part (a) of  FIG.  83   , the first cylindrical portion  2202   a  of the projecting member  2202  abuts on the surface  2203   d  of the shutter  2203 , and positioning thereof is effected in the first direction D 1 . Further, the projecting member  2202  abuts on the support surface  2203   n  of the snap-fit portion  2203   k  of the shutter  2203  on the first end side of the first direction D 1 , and the hollow cylindrical portion  2203   a  is sandwiched between the surface  2203   d  and the support surface  2203   n . By this, the projecting member  2202  is restricted so as not to disengage off through the shutter  2203  in the first direction D 1 . 
     On the other hand, as shown in part (b) of  FIG.  83   , in the rotational direction about the central axis A, the end surface  2202   g  of the projecting member  2202   e  of the projecting member  2202  abuts the surface  2203   g  of the shutter  2203 . This position is referred to as a first position. 
     Here, the projecting member  2202  is supported so as to be rotatable relative to the shutter  2203  in a certain range in the rotational direction centered on the central axis A, and in other words, the projecting member  2202  is supported so as to be movable relative to the shutter  2203  between the first position and the second position in the rotational direction centered on the rotational axis A. The projecting member  2202  is supported by the shutter  2203  so that the projecting portion  2202   b  projects beyond the lower surface of the shutter  2203  as shown in  FIG.  83   , when the projecting member  2202   b  is oriented in the predetermined direction such that it projects downward (gravity direction) and the central axis A is in the gravity direction. Further, as shown in part (a) of  FIG.  83    and part (b) of  FIG.  79   , when the projecting member  2202   b  projects downward and the central axis A is oriented in a predetermined direction facing the direction of gravity, as shown in part (a) of  FIG.  83    and part (b) of  FIG.  79   , and the projecting member  2202  is supported by the shutter  2203  so as to project (project) downward beyond the lower surface  2203   v  of the shutter  2203 . Further, as shown in part (b) of  FIG.  83   , the projecting member  2202  (projecting portion  2202   b ) is placed at the position closer to the central axis A in the radial direction r than the driven transmission portion  2203   u  of the shutter  2203  as viewed in the direction of the central axis A. 
     (Mounting of Attachment) 
     That is, the attachment  2230  is moved downward (in the direction of arrow N) toward the mounting portion  206  in a state of being oriented in the predetermined direction described above, and is mounted to the mounting portion  206 . 
     At this time, the driven transmission portion  2203   u  of the shutter  2203  shown in part (b) of  FIG.  83    is engaged with the driven transmission portion  209   e  (shutter projection, see  FIG.  44   ) of the apparatus-side shutter  209 . By doing so, the shutter opening  2203   t  of the shutter  2203  and the receiving opening  209   a  of the apparatus-side shutter  209  are brought into fluid communication with each other. In addition, the inner peripheral surface  2202   b   1  of the projecting portion  2202   b  of the projecting member  2202  is fitted (engaged) with the small diameter portion  209   d   2  of the center boss  209   d  of the mounting portion  206 . 
     Similarly to Embodiment 2, when the restriction releasing portion of the projecting member  2202   b  of the attachment  2230  (same as the projecting portion  202   b  of Embodiment 2) acts on the releasing member  214  of the mounting portion  206 , the rotation restriction for the shutter  209  by the apparatus-side the rotation restricting mechanism  212  is released. Thereafter, with the rotation of the operating lever  208  shown in part (a) of  FIG.  41    and part (b) of  FIG.  41   , the shutter  2203  is rotated in the direction of an arrow D together with the apparatus-side shutter  209 . 
     Referring to  FIGS.  84  and  85   , the operation of the attachment  2230  in association with the rotation of the operating lever  208  from the closed position to the open position will be described in detail. Part (a) of  FIG.  84   , (b) and (c) are enlarged side views of a part of the mounting portion  206  (cover  210 , restricting member  213 , releasing member  214 ) and a connecting portion of the attachment  2230 , illustrating the operation of the attachment  2230 . Part (a) of  FIG.  84    is a side view when the operating lever  208  (not shown) is in the closed position, and part (b) of  FIG.  84    is a side view of when the operating lever  208  between the closed position and the open position, and part (c) of  FIG.  84    is a side view when the operating lever  208  is in the open position. Part (a) of  FIG.  85   , Figure (b) and Figure (c) are cross-sectional views taken along a line X 2203 -X 2203  in part (a) of  FIG.  84    corresponding to part (a) of  FIG.  84   , part (b) of  FIG.  84    and part (c) of  FIG.  84   , respectively. 
     Part (a) of  FIG.  84    and part (a) of  FIG.  85    show a state in which the attachment  2230  is mounted on the mounting portion  206  and the operating lever  208  is in the closed position. At this time, similarly to Embodiment 2, as the attachment  2230  is being mounted to the mounting portion  206 , the restriction releasing portion of the projecting member  2202   b  (same as the projecting portion  202   b  of Embodiment 2) acts on the releasing member  214  to release the rotation restriction effected by the rotation restricting mechanism  212  of the apparatus side shutter  209 . 
     Next, when the operating lever  208  is rotated, the shutter  2203  also rotates in the direction of arrow D, and the state shown in part (b) of  FIG.  84    and part (b) of  FIG.  85    is reached. At this time, with the rotation of the shutter  2203 , the projecting member  2202  fitted to the shutter  2203  with slight tightness also receives the frictional force from the shutter  2203  and rotates in the direction of the arrow D. 
     Here, since the projecting member  2202   b  is engaged with the releasing member  214 , the releasing member  214  also rotates in the direction of arrow D together with the projecting member  2202 . The attachment  2230  rotated in the direction of arrow D has stopped moving in the rotational direction by the abutment between the rise restricted surface  214   c  and the restricting member  213 . At this time, as shown in part (b) of  FIG.  85   , in the rotational direction centered on the central axis A, the projecting member  2202  maintains the first position where the end surface  2202   g  of the projecting member  2202   e  abuts against the surface  2203   g  of the shutter  2203 . 
     Next, when the operating lever  208  is further rotated in the direction of arrow D against the friction with the projecting member  2202 , the operating lever  208  is in the open position as shown in part (c) of  FIG.  84    and part (c) of  FIG.  85   . At this time, in the rotational direction about the central axis A, the end surface  2202   g  of the projecting member  2202  is not in contact with the surface  2203   g  of the shutter  2203 . The position of the projecting member  2202  at this time when the operating lever  208  is placed in the open position is the second position. 
     In the state shown in part (c) of  FIG.  84    and part (c) of  FIG.  85   , the receiving opening  209   a  of the apparatus-side shutter  209  is exposed. Thereafter, as shown in  FIG.  86   , the user mounts, a toner pack  2220  provided with a straw-shaped discharge member  2220   a , for example to the receiving opening  209   a , and can supply the toner in the accommodating portion  2201  to the toner accommodating chamber  36  of the developer container  32 . 
     For example, as shown in  FIG.  87   , a lid member  2250  may be structured to be mounted to the attachment  2230  while the attachment  2230  is still mounted to the mounting portion  206 . 
     When removing the attachment  2230 , the operating lever  208  is rotated from the open position to the closed position in the direction of arrow E. Then, the operating lever  208 , the shutter  2203 , the projecting member  2202 , and the releasing member  214  are interlocked to rotate in an arrow E direction in the reverse order of the operation associated with the rotation from the closed position to the open position described above. At this time, the operating lever moves from the open position to the closed position, and the projecting member  2202  moves from the second position to the first position. 
     Thereafter, by pulling out the attachment  2230  in the direction of arrow G (see  FIG.  67   ) in the same manner as in Embodiment 2, the attachment  2230  is taken out from the mounting portion  206 . 
     As described above, also in the mounting kit comprising the attachment  2230  including the projecting member  2202  and the shutter  2203 , and the toner pack  2220  including the accommodating portion, it is possible to release the rotation restriction for the shutter  209  by the apparatus-side rotation restricting mechanism  212  and to replenish the toner from the toner pack  2220  to the toner accommodating chamber  36  of the developer container  32 , similarly to Embodiment 2. 
     Further, in this modified example, the projecting member  2202  is structured to be movable within a predetermined range in the rotational direction about the central axis A relative to the mounting portion  206 , but the same effect can be provided even when a positioning portion for positioning in the rotational direction about the central axis A with respect to the cover  210  as in Modified Example 1 without movement. 
     Further, as for the structure of the projecting member  2202   b  in this modified example, the structure of this modified example can be applied to the modified examples of embodiment 2 as well as to the projecting portion  202   b  of Embodiment 2. 
     Modified Example 3 
     In this embodiment (Embodiment 2), the first slope  204   a   1  and the second slope  204   a   2  of the first restriction releasing portion  204   a  are different slopes, and the second restriction releasing portion  204   b  has the same structure. However, as shown in  FIG.  88   , the two slopes may have a smoothly continuous surface. Referring to  FIGS.  88  to  91   , the structure in this case will be described as an example of this modified example. In this modified example, the first slope  204   a   1  and the second slope  204   a   2  of the first restriction releasing portion  204   a  and the first slope  204   a   1  and the second slope  204   a   2  of the second restriction releasing portion  204   b  of this embodiment are changed to have a smoothly continuous surface. The structure is the same as that of this embodiment except for this changed portion, and therefore, the description thereof will be omitted. 
       FIG.  88    is an illustration of detailed shapes of a first restriction releasing portion  2304   a  (first projection) and a second restriction releasing portion  2304   b  (second projection) of this modified example. Part (a) of  FIG.  88    is a perspective view of the first restriction releasing portion  2304   a  and the second restriction releasing portion  2304   b  as viewed from the side (nozzle side) of the second end portion in the first direction D 1 . Part (b) of  FIG.  88    is a view of the first restriction releasing portion  2304   a  as viewed in a direction perpendicular to the rotational axis A. Part (c) of  FIG.  88    is a sectional view taken along a line X 2301 -X 2301  in part (b) of  FIG.  88   . Part (d) of  FIG.  88    is a view of the first restriction releasing portion  2304   a  viewed in the direction of arrow U (upward). 
     As shown in part (a) of  FIG.  88   , the projecting portion  2302   b  of the nozzle  2302  is provided with a restriction releasing portion  2304  including the first restriction releasing portion  2304   a  and the second restriction releasing portion  2304   b . The first restriction releasing portion  2304   a  includes a first slope  2304   a   1  (downward surface, downward guide surface, downward force applying surface, downward push surface), a second slope  2304   a   2  (upward surface, upward guide surface), abutment surface  2304   a   3  (downstream side end surface, abutted surface)). 
     As shown in part (b) of  FIG.  88   , the first slope  2304   a   1  faces the arrow N direction (downward), and it goes up in the arrow U direction (upward) as goes in the rotational direction K (first rotational direction) about the rotational axis A. 
     Here, as shown in part (a) of  FIG.  88    and part (d) of  FIG.  88   , an end of the first slope  2304   a   1  on the side closer to the rotational axis A in the radial direction r of the imaginary circle VC centered on the rotational axis A is referred to as an inner end  2304   a   4  (inner edge line, inner ridge line). In addition, the inner end  2304   a   4  includes an inner upstream end  2304   a   4 U (inner upstream edge line, inner upstream ridge line) on the upstream side in the rotational direction K and, an inner downstream end  2304   a   4 D (inner downstream edge line, inner downstream ridge line) on the downstream side, and an inner intermediate end  2304   a   4 I (inner intermediate edge line, inner intermediate ridge line) connecting them. The inner downstream end  2304   a   4 D is more remote from the rotational axis A in the radial direction r of the imaginary circle VC centered on the rotational axis A than the inner upstream end  2304   a   4 U. In this embodiment, as shown in part (d) of  FIG.  88   , the inner upstream end  2304   a   4 U and the inner downstream end  2304   a   4 D, have a first arc and a second arc centered on the rotational axis A, the second arc having a radius larger than that of the first arc as viewed in the direction of the rotational axis A. The inner intermediate end  2304   a   4 I extends in the radial direction r so as to connect the first arc and the second arc. 
     In addition, as shown in part (a) of  FIG.  88    and part (d) of  FIG.  88   , an end of the first slope  2304   a   1  on the side remote from the rotational axis A in the radial direction r of the imaginary circle VC centered on the rotational axis A is referred to as an outer end  2304   a   5  (outer edge line, outer ridge line). Further, the outer end  2304   a   5  includes an outer upstream end  2304   a   5 U (outer upstream edge line, outer upstream ridge line) on the upstream side in the rotational direction K, an outer downstream end  2304   a   5 D (outer downstream edge line, outer downstream ridge line) on the downstream side an outer intermediate end  2304   a   5 I (outer intermediate edge line, outer intermediate ridge line) connecting them. The outer downstream end  2304   a   5 D is at a position more remote from the rotational axis A in the radial direction r of the imaginary circle VC centered on the rotational axis A than the outer upstream end  2304   a   5 U. In this embodiment, as shown in part (d) of  FIG.  88   , the outer upstream end  2304   a   5 U and the outer downstream end  2304   a   5 D have a third arc and a fourth arc centered on the rotational axis A, as viewed in the direction of the rotational axis A, the fourth arc having a radius larger than that of the third arc. The outer intermediate end  2304   a   5 I extends in the radial direction r so as to connect the third arc and the fourth arc. 
     As shown in part (b) of  FIG.  88   , at least a part of the second slope  2304   a   2  is provided on the arrow U direction (upward) side of at least a part of the first slope  2304   a   1 . 
     As shown in part (c) of  FIG.  88   , the first slope  2304   a   1  at this time has a first slope inside portion  2304   a   1 I inside the second slope  2304   a   2  in the radial direction r of the imaginary circle VC centered on the rotational axis A. In addition, the first slope  2304   a   1  has a first slope outside portion  2304   a   10  at substantially the same position, in the radial direction r of the imaginary circle VC centered on the rotational axis A, as the position of the second slope  2304   a   2 . At this time, at least a part of the inner side  2304   a   1 I of the first slope and at least a part of the outer side  2304   a   10  of the first slope overlap in the rotational direction K (see also part (d) of  FIG.  88   ). 
     The abutment surface  2304   a   3  is provided on the arrow U direction side of (above) from the downstream side end, in the rotational direction K, of the first slope inner side  2304   a   1 I. At least a part of the inner side  2304   a   1 I of the first slope and at least a part of the outer side  2304   a   10  of the first slope overlap with each other in the rotational direction K, and therefore, the abutment surface  2304   a   3  overlaps with the outer side  2304   a   10  of the first slope in the rotational direction K. 
     As shown in part (a) of  FIG.  88   , the second restriction releasing portion  2304   b  has a first slope  2304   b   1  (downward surface, downward guide surface, downward force applying surface) and a second slope  2304   b   2  (upward surface, upward guide surface, abutment surface  2304   b   3 . Here, the first restriction releasing portion  2304   a  and the second restriction releasing portion  2304   b  have a shape which is 180-degree rotationally symmetric with respect to the rotational axis A. Therefore, the detailed description of the second restriction releasing portion  2304   b  will be omitted. 
     Next, referring to  FIGS.  89  and  90   , a mechanism for releasing the rotation restriction of the apparatus-side shutter  209  effected by the rotation restricting mechanism  212 , by mounting the toner pack  2320  of this modified example to the mounting portion  206  will be described.  FIG.  89    illustrates the operation of rotating the releasing claw  214   e  by the first slope  2304   a   1  of the first restriction releasing portion  2304   a , and part (a), part (c), and part (e) of  FIG.  89    show the process. Further, in  FIG.  89   , part (b) thereof is a sectional view taken along a line X 2302 -X 2302  in the state shown in part (a) of  FIG.  89   , part (d) thereof is a sectional view taken along a line X 2303 -X 2303  in the state of part (c) of  FIG.  89   , and part (f) thereof is a sectional view taken along a line X 2304 -X 2304 —in the state shown in part (e) of  FIG.  89   .  FIG.  90    shows an operation in which the releasing claw  214   e  is moved by the second slope  2304   a   2  of the first restriction releasing portion  2304   a . For the sake of better illustration, only the nozzle  2302  (restriction releasing portion  2304 ), the restricting member  213 , and the releasing member  214  are shown in each part of this Figure. Further, in part (c) of  FIG.  89   , the hidden part of the abutment surface  214   a   3  which overlaps with the rotational axis A is clearly shown by a thin line only in this part of the Figure. 
     By mounting the toner pack  2320 , as shown in part (a) of  FIG.  89   , the first slope  2304   a   1  of the first restriction releasing portion  2304   a  is brought into contact with the first guided surface  214   e   1  of the releasing claw  214   e . At this time, as shown in part (b) of  FIG.  89   , the first guided surface  214   e   1  of the releasing claw  214   e  contacts the inner side  2304   a   1 I of the first slope of the first restriction releasing portion  2304   a.    
     When the toner pack  2320  is further moved in the arrow N direction (downward) from this position, the releasing member  214  rotates in the rotational direction D shown in part (a) of  FIG.  89    by the same operation as in this embodiment. That is, the releasing member  214  is rotated in the rotational direction D by receiving a force while the first guided surface  214   e   1  is guided by the inner side  2304   a   1 I of the first slope. Then, as shown in part (c) of  FIG.  89   , the releasing member  214  is in a state of being rotated in the rotational direction D until the first guided surface  214   e   1  passes the downstream end of the first slope inner side  2304   a   1 I in the rotational direction D. At this time, the contact between the first guided surface  214   e   1  of the releasing claw  214   e  and the first slope  2304   a   1  of the first restriction releasing portion  2304   a  is released, and the rotation of the releasing claw  214   e  in the rotational direction D is stopped. In addition, as described above, the inner downstream end  2304   a   4 D of the first restriction releasing portion  2304   a  is placed at a position more remote from the rotational axis A in the radial direction r of the imaginary circle VC centered on the rotational axis A than the inner upstream end  2304   a   4 U (part (d) of  FIG.  88   ). Therefore, as shown in part (d) of  FIG.  89   , there is a space S 230  on the arrow G direction side (upper side) of the releasing claw  214   e.    
     When the toner pack  2320  is further moved in the arrow N direction (downward) from this position, the releasing claw  214   e  enters the space S 230  in the arrow G direction (upward). At this time, by the moment M 202  (urging force) provided by the releasing spring  216  (see  FIG.  50   ) shown in part (c) of  FIG.  89   , the contact surface  214   f  of the releasing claw  214   e  is brought into contact with the abutment surface  2304   a   3  of the first restriction releasing portion  2304   a . By this, the releasing claw  214   e  is in a state in which rotation in the rotational direction E is restricted. At this time, since the abutment surface  2304   a   3  of the first restriction releasing portion  2304   a  overlaps the first slope outer side  2304   a   10  in the rotational direction K, the first slope outer side  2304   a   10  overlaps with the second guided surface  214   e   2  of the releasing claw  214   e  in the direction D. Then, as shown in part (e) of  FIG.  89   , the first slope  214   a   1  of the first restriction releasing portion  2304   a  contacts the second guided surface  214   e   2  of the releasing claw  214   e . At this time, as shown in part (f) of  FIG.  89   , the second guided surface  214   e   2  of the releasing claw  214   e  contacts the outer side  2304   a   10  of the first slope of the first restriction releasing portion  2304   a.    
     When the toner pack  2320  is further moved in the arrow N direction (downward) from this position, the releasing member  214  rotates in the rotational direction D shown in part (e) of  FIG.  89    by the same operation as in this embodiment. That is, the releasing member  214  is rotated in the rotational direction D by receiving a force while the second guided surface  214   e   2  is guided by the outer side  2304   a   10  of the first slope. 
     Then, the releasing member  214  rotates in the rotational direction D until the second guided surface  214   e   2  passes the downstream end of the first slope outer side  2304   a   10  of the first restriction releasing portion  2304   a  in the rotational direction D. The operation up to this point is the first step in this modified example. 
     After the first step, as shown in part (a) of  FIG.  90   , the third guided surface  214   e   3  of the releasing claw  214   e  rides on the downstream end of the second slope  2304   a   2  of the first restriction releasing portion  2304   a  in the rotational direction D. Hereinafter, by the same operation as in this embodiment, as shown in part (b) of  FIG.  90   , the contact surface  214   a  and the contact surface  214   f  of the releasing member  214  abut against the abutment surface  2304   a   3  of the first restriction releasing portion  2304   a . Then, the rotation restriction of the apparatus-side shutter (see  FIG.  40   ) by the rotation restricting mechanism  212  is released. 
     As described above, in this modified example, the first slope  204   a   1  and the second slope  204   a   2  of the first restriction releasing portion  2304   a  in the embodiment which this modified example is based on have a smoothly continuous surface, and the first slope  204   b   1  and the second of the second restriction releasing portion  204   b  of the base embodiment are made continuous with each other. By this, it is sufficient to process one surface to provide the two surfaces, and therefore, the effect of reducing the processing man-hours can be expected. 
     In this modified example, the first slope  2304   a   1  of the first restriction releasing portion  2304   a  has an inner intermediate end  2304   a   4 I between the inner upstream end  2304   a   4 U and the inner downstream end  2304   a   4 D of the inner end  2304   a   4 . This is because there is an abutment surface  2304   a   3 . The same applies to the second restriction releasing portion  2304   b.    
     Next, another structure will be described. As shown in  FIG.  91   , the projection  23102   b  of the nozzle  23102  is provided with a restriction releasing portion  23104  including a first restriction releasing portion  23104   a  (first projection) and a second restriction releasing portion  23104   b  (second projection). The inner end  23104   a   4  (inner edge line, inner ridge line) of the first slope  23104   a   1  of the first restriction releasing portion  23104   a  and the inner end  23104   b   4  (inner edge line, inner ridge line) of the first slope  23104   a   1  of the second restriction releasing portion  23104   b  are smoothly continuous from the upstream side to the downstream side in the rotational direction K. Hereinafter, the first restriction releasing portion  23104   a  and the second restriction releasing portion  23104   b  have a shape symmetric with  180  rotations about the rotational axis A, and therefore, only the first restriction releasing portion  23104   a  will be described.  FIG.  91    shows the shape of the first restriction releasing portion  23104   a , and part (a) thereof is a perspective view as seen from the side (nozzle side) of the second end portion in the first direction D 1 , part (b) is a view as seen from the side (nozzle side) of the second end portion in the first direction D 1 , and part (c) is a sectional view taken along a line X 23104 -X 23104  in part (a) of  FIG.  91   . 
     As shown in part (a) of  FIG.  91   , the inner end  23104   a   4  is smoothly continuous toward the outside of the radial direction r of the imaginary circle VC centered on the rotational axis A, as goes toward the downstream side in the rotational direction K. Here, the inner end  23104   a   4  includes an inner upstream end  23104   a   4 U (inner upstream edge line, inner upstream ridge) on the upstream side in the rotational direction K, and an inner downstream end  23104   a   4 D (inner downstream edge line, inner downstream ridge). The inner upstream end  23104   a   4 U and the inner downstream end  23104   a   4 D are ends which extend smoothly continuous. Similarly, the inner end  23104   b   4  includes an inner upstream end  23104   b   4 U (inner upstream edge line, inner upstream ridge) on the upstream side in the rotational direction K and an inner downstream end  23104   b   4 D (inner downstream edge line, inner downstream ridge). The inner upstream end  23104   b   4 U and the inner downstream end  23104   b   4 D are ends which extend smoothly continuous. 
     Further, as shown in part (c) of  FIG.  91   , the first restriction releasing portion  23104   a  includes a first abutment surface  23104   a   5  on the arrow U direction side of (above) the inner end  23104   a   4  and a second abutment surface  23104   a   3  on the arrow U direction side of (above) the second slope  23104   a   2 . Similarly, as shown in part (c) of  FIG.  91   , the second restriction releasing portion  23104   b  includes a first abutment surface  23104   b   5  on the arrow U direction side of (above) the inner end  23104   b   4  and a second abutment surface  23104   b   3  on the arrow U direction side of (above) the second slope  23104   b   2 . 
     Next, Referring to  FIG.  92   , the description will be made as to a mechanism in which the rotation restriction of the apparatus-side shutter  209  by the rotation restricting mechanism  212  is released by mounting the toner pack  23120  using the restriction releasing portion  23104  having another shape of this modified example. However, the description will be made only as to the points different from those of the modified examples, that is, only the operation after the releasing claw  214   e  is rotated in the rotational direction D by the first slope inner side  23104   a   1 I of the first restriction releasing portion  23104   a  to release the contact with the first slope inner side  23104   a   1 I.  FIG.  92    shows a state in which the releasing claw  214   e  has released the contact of the first restriction releasing portion  23104   a  with the inner side  23104   a   1 I of the first slope, and part (a) of  FIG.  92    is a view as seen in a direction perpendicular to the rotational axis A, and part (b) of  FIG.  92    is a sectional view taken along a line X 2306 -X 2306  in part (a) of  FIG.  92   , and part (c) of  FIG.  92    is a cross-sectional view taken along a line X 2307 -X 2307  in part (a) of  FIG.  92   . For the sake of better illustration, only the nozzle  2302  (restriction releasing portion  23104 ), the restricting member  213 , and the releasing member  214  are shown in each Figure. Further, in part (c) of  FIG.  92   , the cut surfaces of the nozzle  2302  (restriction releasing portion  23104 ) and the releasing claw  214   e  (releasing member  214 ) are shaded. 
     In the state shown in part (a) of  FIG.  92   , In the releasing claw  214   e , the contact between the first guided surface  214   e   1  and the inner side  23104   a   1 I of the first slope of the first restriction releasing portion  23104   a  is released, and, and the rotation in the rotational direction D is stopped. Further, as described above, the inner end  23104   a   4  of the first restriction releasing portion  23104   a  has such a shape that it goes outward in the radial direction r of the imaginary circle VC centered on the rotational axis A, as goes in the rotational direction D (part (a) of  FIG.  91   ). Therefore, as shown in part (b) of  FIG.  92   , there is a space S 231  on the arrow G direction side (upper side) of the releasing claw  214   e.    
     When the releasing claw  214   e  enters the space S 231  in the arrow G direction (upward), the releasing claw  214   e  tends to be rotated in the rotational direction E by the moment M 202  (urging force) by the releasing spring  216  (see  FIG.  50   ) shown in part (a) of  FIG.  92   . Then, as shown in part (b) of  FIG.  92    and part (c) of  FIG.  92   , in the releasing claw  214   e , the contact surface  214   f  is brought into contact with the first abutment surface  23104   a   5  of the first restriction releasing portion  23104   a  in the rotational direction E, by the moment M 202 . By this, the releasing claw  214   e  becomes in a state in which rotation in the rotational direction E is restricted. 
     Here, on the cross-section of part (c) of  FIG.  92   , an intersection between the circumscribed circle C 230  centered on the rotational axis A of the contact surface  214   f  of the releasing claw  214   e  and the first abutment surface  23104   a   5  of the first restriction releasing portion  23104   a  is an intersection P 230 . In, the intersection P 230  is set so as to overlap the first slope outer side  2304   a   10  of the first restriction releasing portion  23104   a  with respect to the rotational direction K. Further, since the contact portion between the first abutment surface  23104   a   5  of the first restriction releasing portion  23104   a  and the contact surface  214   f  of the releasing claw  214   e  is the intersection P 230 , as shown in part (a) of  FIG.  92   , the second guided surface  214   e   2  of the releasing claw  214   e  overlaps the outer side  23104   a   10  of the first slope of the first restriction releasing portion  23104   a  with respect to the rotational direction D. 
     When the toner pack  23120  is further moved in the direction of the arrow N (downward) from the state shown in  FIG.  92   , the outer side  2304   a   10  of the first slope of the first restriction releasing portion  23104   a  and the second guided surface  214   e   2  of the releasing claw  214   e  are brought into contact with each other. Thereafter, the rotation restriction of the apparatus-side shutter  209  by the rotation restricting mechanism  212  is released by the same operation as the present modified example. 
     As described in the foregoing, in the restriction releasing portion  23104  having above-described another shape of the present modified example, the inner upstream end  23104   a   4 U and the inner downstream end  23104   a   4 D of the first restriction releasing portion  2304   a  in the present modified example constitute the one smoothly continuous inner end. In addition, the inner upstream end  23104   b   4 U and the inner downstream end  23104   b   4 D of the second restriction releasing portion  23104   b  constitute one smoothly continuous end (edge line, ridge line). By this, the two ridge lines (faces) may be processed as one ridge line (face), and the effect of reducing the processing man-hours can be expected. 
     Modified Example 4 
     Next, referring to  FIGS.  93  to  95   , another structure will be described. The description of the same points as those of the above-described embodiments and modified example will be omitted. In particular, of the elements disclosed in this modified example, those corresponding to the members described in Embodiment 2 are assigned the same names as those of the members of Embodiment 2, and only the points different from those of Embodiment 2 will be described. 
     In Embodiment 2, the projecting portion  202   b  (projection) is integrally provided on the nozzle  202 , but by providing the projection in another component, it is possible to facilitate reuse the projection having in the complicated shape, thus improving recyclability. 
     The structure in which the projecting portion  202   b  is provided on another component other than the nozzle will be described below. 
       FIG.  93    is an external perspective view of the discharge unit  2402  of this modified example.  FIG.  94    is an exploded perspective view of the discharge unit  2402  of this modified example.  FIG.  95    is a perspective view of the toner pack  2420  to which the discharge unit  2402  of this modified example is mounted. 
     As shown in  FIG.  93   , the discharge unit  2402  of this modified example has a cylindrical shape, and a nozzle  2402 A (discharge portion) and a support member  2402 B are arranged substantially coaxially with the rotational axis A. 
     As shown in  FIG.  94   , in the nozzle  2402 A, a cylindrical portion  2402 Aa and a disk portion  2402 Ab having a diameter larger than that of the cylindrical portion  2402 Aa are arranged substantially coaxially with the rotational axis A, in the order named from the first end side in the first direction D 1 . From the disk portion  2402 Ab, a toner feed portion  2402 Ac projecting toward the second end portion in the first direction D 1  is extended. The toner feed portion  2402 Ac is provided with a discharge surface  2402 Ae, which is a surface extending in the rotational axis A direction, on the second end side in the first direction D 1 . 
     A through hole  2402 Ad is provided in the nozzle  2402 A, penetrates the cylindrical portion  2402 Aa, the disk portion  2402 Ab, and the toner feed portion  2402 Ac from the first end side in the first direction D 1 , and it is in fluid communication with the discharge surface  2402 Ae in a direction substantially perpendicular to the rotational axis A. The portion where the through hole  2402 Ad penetrates the discharge surface  2402 Ae is referred to as a discharge opening  2402 Ag (opening). 
     The support member  2402 B has a genuinely cylindrical shape, and includes a first cylindrical portion  2402 Ba, a disk portion  2402 Bc having a diameter larger than that of the first cylindrical portion  2402 Ba and a second cylindrical portion  2402 Be substantially coaxially with the rotational axis A, in this order from the first end portion side in the first direction D 1 . The projecting portion  2402 Bb projects in the direction of the rotational axis A from an end surface  2402 Bg of the second cylindrical portion  2402 Be in the direction of the rotational axis A. 
     The projecting portion  2402 Bb has the same shape as the projecting portion  202   b  of the nozzle  202  of Embodiment 2, And therefore, the description thereof will be omitted. 
     Further, a through hole  2402 Bd is provided in the support member  2402 B, and penetrates the first cylindrical portion  2402 Ba, the disk portion  2402 Bc, and the second cylindrical portion  2402 Be from the first end side of the first direction D 1 , and it is extended to the side hole  2402 Bf (side opening) of the second cylindrical portion  2402 Be. 
     (Assembling of Discharge Unit) 
     On the first end side of the nozzle  2402 A in the first direction D 1 , an accommodating portion  2401  is mounted to the cylindrical portion  2402 Aa without a gap by adhesion or the like (See  FIG.  95   ) 
     As shown in  FIG.  94   , the nozzle  2402 A is provided with a support member  2402 B extending from the second end side in the first direction D 1  substantially coaxially with the rotational axis A. In the support member  2402 B, the first cylindrical portion  2402 Ba is tightly fitted into a recess (not shown) provided in the disk portion  2402 Ab of the nozzle  2402 A. In this manner, the support member  2402 B is coupled with the nozzle  2402 A. 
     In the discharge unit  2402  in which the nozzle  2402 A and the support member  2402 B are coupled, the discharge opening  2402 Ag is disposed at substantially the same position as the position of the discharge opening  202   a  of the nozzle  202  of Embodiment 2. 
     As shown in  FIG.  95   , an orientation (direction in the mounting attitude) of the toner pack  2420  in which at least a part of the discharge unit  2402  is below the accommodating portion  201  and the rotational axis A extends in the gravity direction is as a predetermined direction. When the toner pack  2420  is oriented in a predetermined direction, the projecting portion  2402 Bb projects downward from the end surface  2402 Bg (lower surface) of the support member  2402 B. Further, the projecting portion  2402 Bb is below the discharge opening  2402 Ag. 
     Further, as shown in  FIG.  95   , the pack side shutter  203  is mounted to the discharge unit  2402  by the same method as in Embodiment 2. 
     The method of mounting/dismounting to/from the mounting portion  206  is the same as that of Embodiment 2, and therefore, the description thereof will be omitted. 
     As described in the foregoing, the projecting portion  202   b  can be provided on the support member  2402 B, which is a component different from the nozzle  2402 A. The nozzle  2402 A and the support member  2402 B are fixed by press-fitting, and can be relatively easily removed from each other. Therefore, only the support member  2402 B including the projecting portion  2402 Bb having a complicated shape can be easily removed from the toner pack  2420 . Therefore, it is possible to facilitate the reuse of the support member  2402 B including the projecting portion  2402 Bb, thus improving the recyclability. 
     Modified Example 5 
     Next, referring to  FIGS.  96  to  98   , another structure will be described. The same points as those of the above-described embodiments and modified examples will be omitted. In particular, of the elements disclosed in this modified example, those corresponding to the members described in Embodiment 2 are assigned the same names as those of the members of Embodiment 2, and only the points different from those of Embodiment 2 will be explained. 
       FIG.  96    is a perspective view of the toner pack  2520  of this modified example. Part (a) of  FIG.  97    is a perspective view of the nozzle  2502  of this modified example. Part (b) of  FIG.  97    is a sectional view of the nozzle  2502  of this modified example. 
     In Embodiment 2, the nozzle  202  has a side surface  202   c  extending in the direction of the rotational axis A (central axis), and the discharge opening  202   a  is provided on the side surface  202   c . On the other hand, in this modified example, the discharge opening  2502   k   2  is provided in an end surface of the cylindrical portion  2502   k.    
     The nozzle  2502  of this modified example will be described. 
     As shown in part (a) of  FIG.  97    and part (b) of  FIG.  97   , the nozzle  2502  of this modified example includes a cylindrical portion  2502   k  (pipe) and a main assembly portion  2502   n  (pipe support member) which supports the cylindrical portion  2502   k . The cylindrical portion  2502   k  has a cylindrical shape, and a substantially circular opening  2502   k   1  (reception port) is arranged substantially coaxially with the rotational axis A on the first end side in the first direction D 1 . In addition, a substantially circular discharge opening  2502   k   2  (exit) is provided at the end of the cylindrical portion  2502   k  opposite to the opening  2502   k   1 . As shown in part (b) of  FIG.  97   , the discharge opening  2502   k   2  faces in a direction perpendicular to the rotational axis A. In other words, as shown in part (a) of  FIG.  97   , the discharge opening  2502   k   2  faces the outside in the radial direction r of the imaginary circle VC centered on the rotational axis A. The opening  2502   k   1  and the discharge opening  2502   k   2  are in fluid communication with each other by a communication passage  2502   k   3 . The communication passage  2502   k   3  is a portion having a cylindrical shape bent into a curved shape. That is, in the cylindrical portion  2502   k , the opening  2502   k   1  faces upward and the communication passage  2502   k   3  faces outward in the radial direction r, as goes downward, when the toner pack  2520  is oriented in the predetermined direction (direction of the mounting attitude) in Embodiment 2. 
     Further, the main assembly portion  2502   n  of the nozzle  2502  is provided with a slope portion  2502   m  on the first end side in the first direction D 1  from the opening  2502   k   1 . The slope portion  2502   m  is in the form of a conical slope substantially coaxial with the rotational axis A, and is a slope which inclines toward the second end side in the first direction D 1  as goes to the rotational axis A. 
     The toner in the accommodating portion  201  of the toner pack  2520  passes through the cylindrical portion  2502   k  from the slope portion  2502   m , is discharged through the discharge opening  2502   k   2 , and is replenished into the toner accommodating chamber  36  of the developer container  32 . 
     Further, a projecting portion  2502   b  projects downward from the lower end surface (bottom surface) of the main assembly portion  2502   n  when the toner pack  2520  is oriented in a predetermined direction. The projecting portion  2502   b  has exactly the same shape as the projecting portion  202   b  of Embodiment 2, and therefore, the description thereof will be omitted. 
     In this modified example, the nozzle  202  of Embodiment 2 has the same structure as that of Embodiment 2 except that the nozzle  202  is replaced with the nozzle  2502 , and therefore, the other description thereof will be omitted. 
     In this modified example, the nozzle  2502  is described as a structure in which the main assembly portion  2502   n  and the cylindrical portion  2502   k  are combined, but the cylindrical portion and the main assembly portion may be integrally formed. Further, the cylindrical portion  2502   k  may be a hard member which does not deform, or may be formed of a member which has elasticity and deforms. 
     Further, in this modified example, although the discharge opening  2502   k   2  of the cylindrical portion  2502   k  is fixed so as to face the outside in the radial direction r, the present invention is not limited to such an example. 
     Referring to  FIGS.  98  and  99   , a toner pack  2530  including a nozzle  2503  in which the direction of the discharge opening of the cylindrical portion is variable will be described. 
     With this structure, the projecting portion  2503   b  and the slope portion  2503   m  of the nozzle  2503  have the same shape as the above-mentioned projecting portion  2502   b  and the slope portion  2502   m , respectively, and therefore, the description thereof will be omitted. 
     Part (a) of  FIG.  98    and part (b) of  FIG.  98    are a perspective view and a sectional view of a nozzle  2503  in a state, the discharge opening  2503   k   2  of the cylindrical portion  2503   k  faces downward (direction of the rotational axis A), when the toner pack  2530  is oriented in a predetermined direction. Part (a) of  FIG.  99    and part (b) of  FIG.  99    are a perspective views and a cross-sectional view of the nozzle  2503  in a state in which the discharge opening  2503   k   2  of the cylindrical portion  2503   k  faces the outside in the radial direction r. 
     The cylindrical portion  2503   k  is flexible, and the discharge opening  2503   k   2  faces downward as shown in part (a) of  FIG.  98    and part (b) of  FIG.  98    in an unused fresh state. The receiving opening  2503   k   1  for receiving the toner from the accommodating portion  201  faces upward. When the toner pack  2530  is mounted on the mounting portion  206 , the user can change the direction of the cylindrical portion  2503   k  so that it faces the outside in the radial direction r. The discharge opening  2503   k   2  of the cylindrical portion  2503   k  may be structured to face upward or inward in the radial direction r in the unused fresh state. That is, it will suffice if the discharge opening  2503   k   2  is structured to face the outside in the radial direction r when the toner pack  2530  is mounted on the mounting portion  206 . 
     Modified Example 6 
     In the present embodiment, the first restriction releasing portion  204   a  includes the first slope  204   a   1 , the second slope  204   a   2 , the third slope  204   a   3 , and the abutment surface  204   a   5 , and the second restriction releasing portion  204   b  has the structure of 180-degree rotationally symmetric with respect to the rotational axis A (central axis) of the first restriction releasing portion  204   a . However, the present invention is not limited to such a structure. In this modified example, a structure in which the functions of the first restriction releasing portion and the second restriction releasing portion are separated will be described. 
     The second restriction releasing portion  2604   b  (second projection) of this modified example is provided on the opposite side of the rotational axis A from the first restriction releasing portion  2604   a  (first projection), and is provided at a position different from that of the first restriction releasing portion  2604   a  in the circumferential direction of the imaginary circle VC (part (c) of  FIG.  100   ). Further, the first restriction releasing portion  2604   a  and the second restriction releasing portion  2604   b  overlap each other when viewed in the radial direction r of the imaginary circle VC (part (b) of  FIG.  100   ). 
     As shown in part (a) of  FIG.  100   , the first restriction releasing portion  2604   a  includes a second slope  2604   a   2  (second downward surface, second downward guide surface, second force applying surface) and a third slope  2604   a   3  (upward surface, an upward guide surface), and an abutment surface  2604   a   5 . The second restriction releasing portion  2604   b  includes a first slope  2604   b   1  (first downward surface, first downward surface, first force applying surface) and an abutment surface  2604   b   5 . The first restriction releasing portion  2604   a  does not include a slope corresponding to the first slope  2604   b   1 , and the second restriction releasing portion  2604   b  does not include a slope corresponding to the second slope  2604   a   2  and the third slope  2604   a   3 . 
     As shown in part (a) of  FIG.  65   , part (b) of  FIG.  65    and  FIG.  67   , the first slope  2604   b   1  of the second restriction releasing portion  2604   b  applies the force, while guiding the first guided surface  214   e   1  of the releasing member  214 . By this as viewed in the direction of the rotational axis A, the releasing member  214  is rotated in the rotational direction D to a position where the second guided surface  214   e   2  and the third guided surface  214   e   3  of the releasing member  214  are exposed through the cover  210 . 
     On the other hand, as shown in part (c) of  FIG.  65   , the second slope  2604   a   2  of the first restriction releasing portion  2604   a  rotates the releasing member  214  to the position where, the rise restricted surface  214   c  does not overlap the rise restricting surface  210   e  of the cover  210  as viewed in the direction of the rotational axis A. In addition, as shown in part (a) of  FIG.  66   , the third slope  2604   a   3  of the first restriction releasing portion  2604  guides the releasing member  214  so that the releasing member  214  moves upward while being rotated in the rotational direction E. 
     As described above, it is possible to employ a structure of a projecting portion in which the functions of the first restriction releasing portion  2604   a  and the second restriction releasing portion  2604   b  are separated. 
     Modified Example 7 
     Although the toner pack  220  of Embodiment 2 includes the pack side shutter  203 , it may have a structure not including the pack side shutter  203 . 
     A method of supplying toner to the image forming apparatus by using the toner pack  220  not provided with the pack side shutter  203  will be described. 
     Part (a) of  FIG.  101    is a perspective view of a toner pack  2820  not provided with the pack-side shutter. Part (b) of  FIG.  101   , part (c) of  FIG.  101    and part (d) of  FIG.  101    are a left side view, a front view, and a right side view of the toner pack  220  without the pack side shutter  203 , respectively. A nozzle  2802  is provided with a discharge opening  2802   a  (opening, nozzle opening) and a projecting portion  2802   b . An accommodating portion  2801  and a nozzle  2802  are shown in a simplified manner in shape for the sake of better illustration, but are exactly the same as those in Embodiment 2. Instead of including the pack-side shutter, a sealing member s 1  seals the discharge opening  2802   a  of the nozzle  2802 . One end of the sealing member s 1  extends to above the accommodating portion  2801 . 
     Part (a) of  FIG.  102    is a perspective view of the toner pack  2820  and the mounting portion  206  in a state in which the toner pack  2820  including no pack-side shutter is mounted on the mounting portion  206 . Part (d) of  FIG.  102    shows a rod  2821  to be used to open the apparatus-side shutter  209 . Part (b) of  FIGS.  102  and  102    ( c ) are perspective views illustrating the state before and after the user opens the apparatus-side shutter  209  using the rod  2821 , respectively. Part (d) of  FIG.  102    is a perspective view of the toner pack  220  and the mounting portion  206  in the state of part (c) of  FIG.  102    after the sealing member s 1  is pulled out. 
     In the case of the toner pack  2820  without the pack side shutter, the apparatus-side shutter  209  cannot be opened even if the operating lever  208  is operated as described above. Therefore, by mounting the toner pack  2820  on the mounting portion  206 , the rotation restriction of the apparatus-side shutter  209  of the rotation restricting mechanism  212  is first released by the projecting portion  2802   b  (part (a) of  FIG.  102   ). Thereafter, the rod  2821  is inserted into the gap between the hole portion of the mounting portion  206  and the nozzle  2802 , and the free end bending portion  2821   a  of the rod is engaged with the shutter projection  209   i  on the apparatus-side (part (b) of  FIG.  102   ). Next, the rod  2821  is moved in the rotational direction D so as to rotate the apparatus-side shutter  209  from the closed position (part (b) of  FIG.  102   ) to the open position (part (c) of  FIG.  102   ). Then, the sealing member s 1  is pulled out upward to unseal the discharge opening  2802   a  of the nozzle  2802 . When the accommodating portion  2801  is compressed by the user in this state, the toner is discharged through the discharge opening  2802   a  of the nozzle  2802  and is supplied into the toner accommodating chamber  36  of the developer container  32  through the apparatus-side opening  217   a  of the second frame  217 . 
     As described above, the toner pack  220  may not have the shutter  203  on the pack side. 
     Embodiment 3 
     Next, referring to  FIGS.  103  to  111   , Embodiment 3 will be described in the following. In this embodiment, the third slope of the restriction releasing portion is perpendicular to the rotational axis A, as compared with Embodiment 2. In addition, the projecting portion  202   b  in Embodiment 2 is structured to move along the rotational axis A. The same points as in the above-described embodiments will be omitted. In particular, of the elements disclosed in this embodiment, those corresponding to the members described in Embodiment 2 are assigned the same names as those of the members of Embodiment 2, and only the points different from those of Embodiment 2 will be described. 
     (Toner Pack Structure) 
     Referring to  FIGS.  103  to  107   , the overall structure of the toner pack will first be described.  FIG.  103    is an illustration of an appearance of the toner pack  320 .  FIG.  104    is an exploded perspective view of the nozzle  302  and the portions assembled to the nozzle  302 , and shows the parts assembled from the side of the first end portion (accommodation portion side) in the first direction D 1 .  FIG.  105    is an exploded perspective view of the nozzle  302  and the portions assembled to the nozzle  302 , and shows the parts assembled from the opposite side of the first end portion side (accommodation portion side) of the first direction D 1 .  FIG.  106    is a perspective view illustrating detailed shape of the restriction releasing member  304 .  FIG.  107    is a sectional view of the toner pack  320  taken along a line X 301 -X 301  shown in  FIG.  103   , that is, along the pin  333  at the time when the restriction releasing member  304  which will be described hereinafter projects in a direction of the arrow N. 
     As shown in  FIG.  103   , the toner pack  320  in this embodiment comprises, a nozzle  302  (discharging portion), a restriction releasing member  304 , and an operating member  330 , in addition to the accommodating portion  201  and the pack side shutter  203  which have the same shapes as those of Embodiment 2. Further, although the details will be described hereinafter, in order to operate the restriction releasing member  304  when the operating member  330  is operated, a shaft member  331 , a shaft seal  332  (see  FIG.  104   ), a pin  333 , a shaft ring  334 , and a shaft ring  335  (see  FIG.  105   ). Hereinafter, these portions will be described in detail. In the following description, unless otherwise specified the toner pack  320  is oriented in a predetermined direction in which at least a part of the nozzle  302  is below the accommodating portion  201  and in which the rotational axis A faces the direction of gravity. 
     As shown in  FIG.  104   , the nozzle  302  has a substantially cylindrical shape centered on the rotational axis A. A hole portion  302   e  (guide groove) is provided in the cylinder  302   g  (guide portion) on the side (see  FIG.  103   ) to be assembled with the accommodating portion  201  of the nozzle  302 . The hole portion  302   e  has an elongated hole shape extended in such a direction as goes up (upward) in the direction of the arrow U (upward) of the rotational axis A direction as goes in the rotational direction K. Further, a pair of hole portions  302   e  are provided so as to provide 180-degree rotational symmetric arrangement about the rotational axis A of the nozzle  302 . 
     As shown in  FIG.  105   , the nozzle  302  is provided with a cylindrical surface  302   i  (side surface) on the arrow N direction (downward) side of the cylinder  302   g . An opening  302   a  (discharge opening) facing in the radial direction of the rotational axis A is provided in the cylindrical surface  302   i . In addition, a passage  302   j  is provided as a space that passes through the inside of the nozzle  302  and is connected to the opening  302   a . Further, an end surface  302   h  is on the arrow N direction (downward) side of the nozzle  302 , is provided with a cylindrical support portion  302   b  projecting in the arrow N direction (downward). Furthermore, the cylindrical support portion  302   b  is provided with a pair of cut-away portions  302   c  so as to provide 180-degree rotational symmetric arrangement about the rotational axis A. As shown in  FIG.  107   , a cylindrical groove  302   d  centered on the rotational axis A is provided on a passage  302   j  of the nozzle  302 . A hole portion  302   f  centered on the rotational axis A is provided on the end surface of the cylindrical groove  302   d  on the arrow N direction (downward) side. 
     As shown in  FIG.  105   , the restriction releasing member  304  has a substantially cylindrical shape centered on the rotational axis A. A restriction releasing member  304  is provided with a pair of projections  304   d  projecting in the radial direction of the rotational axis A from the cylindrical portion  304   c . The pair of projections  304   d  are positioned so as to provide 180-degree rotationally symmetric arrangement with respect to the rotational axis A. The restriction releasing member  304  includes a first restriction releasing portion  304   a  (first projection) and a second restriction releasing portion  304   b  (second projection) projecting in the arrow N direction (downward) from the end portion  304   e  on the arrow N direction (downward) side. The first restriction releasing portion  304   a  and the second restriction releasing portion  304   b  are arranged so as to be 180-degree rotatable member symmetric arrangement with respect to the rotational axis A. Of the first restriction releasing portion  304   a  and the second restriction releasing portion  304   b  the one on the side closer to the opening  302   a  in the rotational direction K of the rotational axis A in a state in which the restriction releasing member  304  which will be described hereinafter is assembled to the nozzle  302  is referred to as the first restriction releasing portion  304   a . As shown in part (a) of  FIG.  106    and part (b) of  FIG.  106   , the first restriction releasing portion  304   a  comprises a first slope  304   a   1  (first inner engaging surface, first downward surface, first downward guide surface, first force applying surface, first push surface), second slope  304   a   2  (first outer engaging surface, second downward surface, second downward guide surface, second force applying surface, second push surface), flat surface  304   a   3  (second engagement surface, upward surface, upward engaging surface, upward push surface, upward force applying surface), a first abutment surface  304   a   5 , and a second abutment surface  304   a   6 . The first slope  304   a   1 , the second slope  304   a   2 , and the first abutment surface  304   a   5  have the same structures as the first slope  204   a   1 , the second slope  204   a   2 , and the abutment surface  204   a   5  in Embodiment 2, respectively, and therefore, the description thereof is omitted. As shown in part (c) of  FIG.  106   , the flat surface  304   a   3  is perpendicular to the rotational axis A. That is, when the toner pack  320  is oriented in a predetermined direction, the flat surface  304   a   3  extends in the horizontal direction perpendicular to the direction of gravity. The flat surface  304   a   3  is placed on the arrow U direction side (upward) of least a part of the second slope  304   a   2 . The second abutment surface  304   a   6  is placed on the upstream side of the flat surface  304   a   3  in the rotational direction K, extends in the arrow U direction (upward), and faces the downstream side in the rotational direction K. Here, as described above, the second restriction releasing portion  304   b  has a shape which is 180-degree rotationally symmetric relative to the first restriction releasing portion  304   a  with respect to the rotational axis A, and therefore the description thereof is omitted. As shown in  FIG.  107   , the restriction releasing member  304  is provided with an end portion  304   f  at the end on the arrow U direction (upward direction) side. The end portion  304   f  is provided with a hole portion  304   g  centered on the rotational axis A. 
     As shown in  FIG.  104   , the operating member  330  has a substantially cylindrical shape centered on the rotational axis A. A substantially cylindrical sealing member  330   b  is provided inside the cylindrical portion  330   a  of the operating member  330 . An elastic member such as urethane foam is used for the sealing member  330   b . The operating member  330  is provided with a pair of hole portions  330   c  penetrating the cylindrical portion  330   a  and the sealing member  330   b  on the symmetric positions about the rotational axis A. The straight line connecting the centers of the pair of hole portions  330   c  is substantially perpendicular to the rotational axis A. 
     The shaft member  331  has an elongated cylindrical shape provided coaxially with the rotational axis A, and comprises a shaft portion  331   b  and a small diameter shaft portion  331   c  having a radius smaller than that of the shaft portion  331   b . In addition, the small diameter shaft portion  331   c  is placed on a more downstream side in the N direction (lower side) than the shaft portion  331   b . The shaft portion  331   b  is provided with a through hole  331   a  substantially perpendicular to the rotational axis A. 
     The shaft seal  332  has a substantially cylindrical shape coaxial with the rotational axis A, and comprises an elastic member such as urethane foam. 
     As shown in  FIG.  105   , the pin  333  has a substantially elongated cylindrical shape. 
     The shaft ring  334  and the shaft ring  335  have substantially disk shapes centered on the rotational axis A, and provided with holes  334   a  and  335   a  in the central portions thereof, respectively. 
     (Assembling of Toner Pack) 
     Next, referring to  FIGS.  104 ,  105 , and  107   , the assembly of the toner pack  320  according to this embodiment will be described. 
     First, as shown in  FIG.  104   , the operating member  330 , the shaft seal  332 , and the shaft member  331  are assembled to the nozzle  302  in this order from the upstream side in the arrow N direction. The operating member  330  is inserted into the cylinder  302   g  of the nozzle  302  until the hole portion  330   c  becomes coincident with the hole portion  302   e . At this time, the sealing member  330   b  of the operating member  330  is brought into close contact with the hole portion  302   e  so as to cover the hole portion  302   e . As shown in  FIG.  107   , the shaft seal  332  is assembled to the cylindrical groove  302   d  of the nozzle  302 . For the shaft member  331 , the small diameter shaft portion  331   c  is inserted into the shaft seal  332  and into the hole portion  302   f  of the nozzle  302 . The small diameter shaft portion  331   c  and the hole portion  302   f  are supported so as to be slidable in the rotational direction K and in the rotational axis A direction. 
     Next, as shown in  FIG.  105   , the pin  333  is assembled to the operating member  330  and the nozzle  302  in the direction of an arrow V 3 , and then the shaft ring  334 , the restriction releasing member  304 , and the shaft ring  335  are mounted to the shaft member  331  in the direction of arrow U (upward). The pin  333  is inserted from one hole portion  330   c  of the operating member  330 , and as shown in  FIG.  107   , and it is inserted in the order of, one hole portion  330   c , one hole portion  302   e , through hole  331   a , the other hole portion  302   e , and the other hole portion  330   c . The pin  333  is supported slidable relative to the pair of hole portions  302   e  and the through hole  331   a . The pin  333  and the pair of hole portions  330   c  are fixed in the direction of arrow V 3  by adhesion or clamping. The shaft ring  334  is fitted on the small diameter shaft portion  331   c  at the hole  334   a , and is fixed at a position away from the free end of the small diameter shaft portion  331   c  in the arrow N direction (downward) by the amount of the thickness of the shaft ring  335  plus the end portion  304   f  of the restriction releasing member  304 . For the shaft member  331 , the shaft diameter d 30  in the region fixed to the shaft ring  334  is selected slightly larger than the diameter d 31  of the hole  334   a  of the shaft ring  334  so that the shaft ring  334  can be press-fitted. The restriction releasing member  304  is fitted on the small diameter shaft portion  331   c  at the hole portion  304   g  until it abuts to the shaft ring  334 , and the hole portion  304   g  and the small diameter shaft portion  331   c  are slidable relative to each other. Further, the restriction releasing member  304  is mounted to the nozzle  302  so that the cylindrical portion  304   c  is inserted into the cylindrical support portion  302   b  and the projection  304   d  is inserted into the cut-away portion  302   c . By the engagement between the projection  304   d  of the restriction releasing member  304  and the cut-away portion  302   c , the restriction releasing member  304  is constrained from moving around the rotational axis A relative to the nozzle  302 . Therefore, the restriction releasing member  304  is supported movably only in the direction of the rotational axis A relative to the nozzle  302 . The shaft ring  335  is fitted on the small diameter shaft portion  331   c  at the hole  335   a  until it abuts to the end portion  304   f  of the restriction releasing member  304 , and it is fixed to the small diameter shaft portion  331   c . The shaft diameter d 30  of the region fixed to the shaft ring  334  of the shaft member  331  is selected to be slightly larger than the diameter d 31  of the hole  334   a  of the shaft ring  334  so that it can be press-fitted with the shaft ring  334 . Further, the shaft diameter d 32  of the region, fixed to the shaft ring  335 , of the shaft member  331  is selected to be slightly larger than the diameter d 33  of the hole  335   a  of the shaft ring  335  so that it can be press-fitted with the shaft ring  335 . 
     Thereafter, the assembling of the toner pack  320  is completed by assembling the pack side shutter  203  or the like to the nozzle  302 . 
     (Operation of Toner Pack) 
     Next, referring to  FIGS.  107  to  109   , the operation of the toner pack  320  when the operating member  330  is operated will be described.  FIG.  108    is a perspective view of components placed downstream, in the N direction (downward) of the arrow N, of the accommodating portion  201 . Part (a) of  FIG.  108    and part (b) of  FIG.  108    show a state in which the pin  333  is at the lower end of the hole portion  302   e  in the arrow N direction (downward). Part (a) of  FIG.  108    shows a state in which the operating member  330  is at the shown position, and part (b) of  FIG.  108    shows a state in which the operating member  330  is not shown. Part (c) of  FIG.  108    and part (d) of  FIG.  108    show a state in which the pin  333  is placed at the upper end of the hole portion  302   e  in the arrow U direction (upward direction). Part (c) of  FIG.  108    shows a state in which the operating member  330  is at the shown position, and part (d) of  FIG.  108    shows a state in which the operating member  330  is not shown.  FIG.  109    is a sectional view of the toner pack  320  in a state in which the pin  333  is at the upper end of the hole portion  302   e  in the arrow U direction (upward direction). Further,  FIG.  109    is the sectional view taken along the same line as in  FIG.  107    (see  FIGS.  103    and X 320 -X 320 ). 
     As shown in part (a) of  FIG.  108   , a case where the operating member  330  is rotated in the direction of an arrow W 30  will be described. The pin  333  is fixed to the hole portion  330   c  of the operating member  330 , and therefore, when the operating member  330  is rotated in the direction of the arrow W 30 , the pin  333  also rotates in the direction of the arrow W 30 . At this time, the pin  333  rotates along the shape of the hole portion  302   e  of the nozzle  302  as shown in part (b) of  FIG.  108   , so that the pin  333  moves in the direction of the arrow U (upward). At this time, the operating member  330  also moves in interrelation with the movement of the pin  333  in the arrow U direction (upward). Further, as shown in  FIG.  107   , since the pin  333  is inserted into the through hole  331   a , the shaft member  331  rises in interrelation with the pin  333 . Further, since the restriction releasing member  304  is fixed to the shaft member  331  in the rotational axis A direction by way of the shaft ring  335 , it moves in interrelation with the shaft member. Therefore, when the operating member  330  is rotated in the direction of the arrow W 30  from the state shown in part (a) of  FIG.  108    and part (b) of  FIG.  108   , and the restriction releasing member  304  is moved by the arrow U direction in interrelation with the movement of the pin  333  in the direction of the arrow U, with the result of the state shown in part (c) of  FIG.  108    and part (d) of  FIG.  108   . Here, the amount of projection of the restriction releasing member  304  from the pack-side shutter  203  in a state where the restriction releasing member  304  is placed at the lower position as in part (a) of  FIG.  108    and part (b) of  FIG.  108    is referred to as P 30 . Further, in the direction of the rotational axis A, a distance which the pin  333  moves in the direction of the arrow U by the operation of the operating member  330  is referred to as the distance L 30 . 
     When the operating member  330  is rotated from the state of part (a) of  FIG.  108    to the state of part (c) of  FIG.  108    in the W 30  direction, the pin  333  moves to the upper end of the hole portion  302   e  as shown in part (d) of  FIG.  108   . Since the pin  333  moves in the arrow U direction (upward) by the distance L 30 , the restriction releasing member  304  also moves in the arrow U direction (upward) by L 30  in interrelation therewith (projection amount P 30  of the restriction releasing member  304  is reduced by the distance L 30  to become the projection amount P 31 ). In addition, as shown in  FIG.  109   , the structure is such that even after the operating member  330  is moved in the direction of the arrow U (upward), the sealing member  330   b  covers the entire hole portion  302   e  and is in close contact with the operating member  330 . 
     (Mounting and Dismounting of Toner Pack) 
     Next, referring to  FIGS.  110  and  111   , mounting/dismounting of the toner pack  320  to/from the mounting portion  206  will be described. As for the mounting/dismounting operation, only the operation different from that of Embodiment 2 will be described.  FIG.  110    is a sectional view illustrating a process in which the restriction releasing member  304  releases the rotation restricting mechanism  212  when the toner pack  320  is mounted to the mounting portion  206 . For the sake of better illustration, the rotation restricting mechanism  212  is shown only by the restricting member  213  and the releasing member  214 . The states of part (a) of  FIG.  110    to part (f) of  FIG.  110    will be described hereinafter.  FIG.  111    is a sectional view illustrating a state when the toner pack  320  is being removed from the mounting portion  206 . 
     A mechanism for releasing the rotation restricting mechanism  212  of the mounting portion  206  by mounting the toner pack  320  on the mounting portion  206  will be described. This mechanism has the same operation up to the first step of Embodiment 2. Part (a) of  FIG.  110    shows a state before the first restriction releasing portion  304   a  and the releasing claw  214   e  of the releasing member  214  come into contact with each other. When the toner pack  320  is moved in the direction of arrow N from this state, the first slope  304   a   1  of the first restriction releasing portion  304   a  and the first guided surface  214   e   1  of the releasing claw  214   e  come into contact with each other as shown in part (b) of  FIG.  110   . It will be in the state of When the toner pack  320  is further moved in the direction of the arrow N from this position, the first guided surface  214   e   1  receives the force while being guided by the first slope  304   a   1 , so that the releasing member  214  is rotated in the rotational direction D. The releasing member  214  is rotated in the rotational direction D until the first guided surface  214   e   1  passes the downstream (in the rotational direction D) end of the first slope  304   a   1 . When the toner pack  320  is further moved in the direction of arrow N from this position, as shown in part (c) of  FIG.  110   , the second slope  304   a   2  of the first restriction releasing portion  304   a  and the second guided surface  214   e   2  of the releasing claw  214   e  are brought into contact with each other. When the toner pack  320  is further moved in the direction of the arrow N from this position, the second guided surface  214   e   2  receives the force while being guided by the second slope  304   a   2  as shown in part (d) of  FIG.  110   , so that the releasing member  214  is rotated in the direction D. The releasing member  214  is rotated in the rotational direction D until the second guided surface  214   e   2  passes the downstream (in the rotational direction D) end of the second slope  304   a   2 . The steps up to this point are the same as in Embodiment 2. Since the portion related to the mechanics by the releasing spring  216  (not shown) and so on is the same as that of Embodiment 2, the description thereof is omitted. 
     When the toner pack  320  is further moved in the direction of arrow N after the first step, the flat surface  304   a   3  passes the third guided surface  214   e   3  of the releasing claw  214   e  in the direction of arrow N. At this time, as shown in part (e) of  FIG.  110   , the releasing claw  214   e  is rotated in the rotational direction E by the moment M 202  (urging force) generated by the releasing spring  216  (see  FIG.  50   ). Then, the contact surface  214   a  of the releasing claw  214   e  abuts to the second abutment surface  304   a   6  of the first restriction releasing portion  304   a . The mounting of the toner pack  320  on the mounting portion  206  in the direction of the arrow N is completed. In this state, the restricting member  213  is not moved in the arrow G direction (upward) together with the releasing member  214 , so that the rotation restriction by the rotation restricting mechanism  212  of the apparatus-side shutter  209  is not released. Therefore, it is necessary to move the releasing member  214  in the arrow G direction. After the mounting of the toner pack  320  on the mounting portion  206  in the direction of arrow N is completed, the operating member  330  is manually rotated in the direction of arrow W 30  as shown in  FIG.  108   . By doing so, as described above, the restriction releasing member  304  moves in the direction of arrow U (upward). That is, the first restriction releasing portion  304   a  of the restriction releasing member  304  also moves in the direction of the arrow U (upward). By this, as shown in part (f) of  FIG.  110   , the end surface  214   e   30  in the arrow N direction side of the releasing claw  214   e  is pushed and moved by, the flat surface  304   a   3  of the first restriction releasing portion  304   a  in the arrow G direction (upward). Therefore, the restricting member  213  can be moved in the arrow G direction (upward) together with the releasing member  214 , so that the rotation restriction by the rotation restricting mechanism  212  of the apparatus-side shutter  209  can be released. That is, the flat surface  304   a   3  of the first restriction releasing portion  304   a  has a function of pushing (force applying) the surface  214   e   30  of the releasing claw  214   e  so that the releasing member  214  moves upward. The first restriction releasing portion  304   a  has a function of a hook for hooking the releasing claw  214   e  and lifting the releasing member  214  upward. 
     With the above-described operations, the toner pack  320  becomes in the mounting complete state. The flat surface  304   a   3 , which is a surface substantially perpendicular to the rotational axis A, is capable of maintaining the releasing member  214  on the arrow G direction side against the urging force F 201  by the restricting spring  215  (see  FIG.  49   ) and the force in the arrow N direction such as gravity. 
     Finally, the removal of the toner pack  320  from the mounting portion  206  will be described. As shown in  FIG.  111   , the toner pack  320  is removed by moving the toner pack  320  in the direction of arrow G. At this time, since the releasing claw  214   e  is engaged with the flat surface  304   a   3  of the first restriction releasing portion  304   a , interference occurs when the toner pack  320  is removed. When the toner pack  320  is moved in the direction of the arrow G by applying a larger force from this position, partial deformation occurs in the first restriction releasing portion  304   a  and the releasing claw  214   e . Due to the partial deformation, the contact surface of the releasing claw  214   e  with the flat surface  304   a   3  is inclined in the direction of arrow G (upward) toward the downstream side in the rotational direction E. By the inclination of the contact surface of the releasing claw  214   e , a release force F 301  is produced for the third guided surface  214   e   3 . Then, the releasing member  214  is rotated in the direction of arrow D by the release force F 301 , and the contact surface  214   a  passes by the end portion of the flat surface  304   a   3  on the rotational direction D side. The releasing claw  214   e  and the flat surface  304   a   3  are disengaged from each other, and therefore, the toner pack  320  becomes movable in the direction of arrow G (upward), so that the toner pack  320  can be removed from the mounting portion  206 . 
     As described above, in the toner pack in this embodiment, the surface of the restriction releasing portion facing the first end side (accommodation portion side) in the first direction D 1  is a surface substantially perpendicular to the rotational axis A. Also in this case, the rotation restriction by the rotation restricting mechanism  212  can be released by providing a structure for moving the restriction releasing portion upward. 
     Modified Example 1 
     In this embodiment, the flat surface  304   a   3  is structured to be substantially perpendicular to the rotational axis A, but as shown in  FIG.  112   , the surface  304   a   3  may have a structure of an inclined surface  3104   a   3  inclined with respect to the rotational axis A. 
     The inclined surface  3104   a   3  (second engaging surface, upward engaging surface, upward engaging surface, upward push surface, upward force applying surface) of the restriction releasing member  3104  is a surface extending so as to goes up in the arrow U direction (upward) as goes in the rotational direction K (first rotational direction) about the rotational axis A (central axis), and at least a part of the inclined surface  3104   a   3  is located on the arrow U direction side (upward) of at least a part of the second slope  304   a   2 . In the this modified example, the same structure as that of the basic embodiment of this modified example is used except for the point that the flat surface  304   a   3  of the basic embodiment is replaced with the inclined surface  3104   a   3 , and therefore other description will be omitted. Further, in the modified example as well, the rotation restriction by the rotation restricting mechanism  212  can be released as in the basic embodiment of this modified example. 
     Modified Example 2 
     In this embodiment, the first slope  304   a   1  and the second slope  304   a   2  of the first restriction releasing portion  304   a  are different slopes, and the second restriction releasing portion  304   b  has the same structure. However, as in Modified Example 3 of Embodiment 2, the two slopes may have smoothly continuous surfaces as in the restriction releasing member  3204  of the toner pack  3220  shown in  FIG.  113   . 
     As shown in  FIG.  113   , the restriction releasing member  3204  includes a first restriction releasing portion  3204   a  (first projection) and a second restriction releasing portion  3204   b  (second projection) which are symmetric with each other with respect to the rotational axis A (central axis). The first restriction releasing portion  3204   a  is provided with a first slope  3204   a   1 , and the first slope  3204   a   1  is structured in the same manner as the first slope  2304   a   1  of Modified Example 3 of Embodiment 2. In addition, the first restriction releasing portion  3204   a  is provided with a flat surface  3204   a   3  (second engaging surface, upward engaging surface, upward engaging surface, upward push surface), and the flat surface  3204   a   3  is structured in the same manner as the flat surface  304   a   3  of the basic embodiment of this modified example. Similarly, the second restriction releasing portion  3204   b  is also provided with a first slope  3204   b   1  and a flat surface  3204   b   3 . 
     Also in this case, the rotation restriction of the apparatus-side shutter  209  by the rotation restricting mechanism  212  can be released. 
     Embodiment 4 
     Next, referring to  FIGS.  114  to  126   , Embodiment 4 will be described in the following. In this embodiment, the structure of the discharge opening is different from that in Embodiment 2. In above-described Embodiment 2, the discharge opening faces the outside of the radial direction r of the imaginary circle VC centered on the rotational axis A, whereas in this embodiment, the discharge opening faces in the direction of the rotational axis A. The nozzle of this embodiment is provided with a movable passage including a discharge opening facing in the direction of the rotational axis A. The movable passage is structured to be movable between a first position stored in the nozzle and a second position projecting from the nozzle. The same points as in the above-described embodiments will be omitted. In particular, of the elements disclosed in this embodiment, those corresponding to the members described in Embodiment 2 are assigned the same names as those of the members in Embodiment 2, and only the points different from those of Embodiment 2 will be described. 
     (Toner Pack Structure) 
     Referring to  FIGS.  114  and  115  to  118   , the structure of the toner pack in this embodiment will be described.  FIG.  114    shows the appearance of the toner pack  420 , and is a view as seen in a direction perpendicular to the first direction D 1 , part (a) of  FIG.  114    is a view as seen from the opening  402   a  side of the nozzle  402 , and part (b) of  FIG.  114    is a view as seen from the side opposite to the opening  402   a .  FIG.  115    is an exploded perspective view of the toner pack  420 , and is a view as seen from the second end side (nozzle side) of the first direction D 1 , part (a) of  FIG.  115    is a view as seen from the opening  402   a  side of the nozzle  402 , and part (b) of  FIG.  115    is a view as seen from the side opposite to the opening  402   a . The accommodating portion  201  and the pack-side shutter  203  are not shown.  FIG.  116    is an illustration of details of the nozzle  402 .  FIG.  117    is an illustration of details of a movable passage  430 . Part (a) of  FIG.  118    is a detailed illustration of a cam member  432 , part (b) of  FIG.  118    is a detailed illustration of an operating member  433 , and part (c) of  FIG.  118    is a details illustration of a shaft member  434 . 
     As shown in part (a) of  FIG.  114   , the toner pack  420  in this embodiment includes, an accommodating portion  201 , a pack side shutter  203 , a nozzle  402 , a movable passage  430 , which have the same shapes of the corresponding elements of embodiment 2, respectively, and as shown in  114  ( b ), it comprises an operation mechanism  436  including an operating member  433  exposed to the outside. 
     As shown in part (a) of  FIG.  115    and part (b) of  FIG.  115   , the nozzle  402  is provided with a movable passage  430 , a tension spring  431 , and an operation mechanism  436 . In this embodiment, the nozzle  402 , the movable passage  430 , the tension spring  431 , and the operation mechanism  436  constitute the discharge portion. In addition, the operation mechanism  436  comprises a cam member  432 , an operating member  433 , a shaft member  434 , and an E-shaped retaining ring  435 . The operation mechanism  436  is provided on the rotational axis A 40  which is parallel to the rotational axis A (central axis) at a different position. The rotational direction K 40  about the rotational axis A 40  is a clockwise direction as viewed from the side (nozzle side) of the second end portion of the first direction D 1 . Further, as to the moving direction of the movable passage  430  relative to the nozzle  402 , the direction toward the outside in the radial direction r of the imaginary circle VC centered on the rotational axis A is an arrow V 40  direction (projecting direction), the direction toward the inside of the radial direction r is an arrow V 41  direction (retracting direction). The direction of the arrow V 40  and the direction of the arrow V 41  are parallel to the opening direction of the opening  402   a  of the nozzle  402 . 
     The detailed shapes of various members will be described. 
     As shown in  FIG.  116   , the nozzle  402  (accepting member) has a generally cylindrical shape having a cylindrical portion  402   c  centered on the rotational axis A, and includes an opening  402   a  (second opening), a sealing member  402   a   1 , a spring hooking portion  402   e , a hole portion  402   d , and a projecting portion  402   b . The nozzle  402  has a function of receiving the toner of the accommodating portion  201 . 
     As shown in part (a) of  FIG.  116   , the cylindrical portion  402   c  has the accommodating portion side cylindrical portion  402   c   1  on the arrow U direction side (upper side) of the pack side shutter  203  in a state where the pack side shutter  203  is assembled (See  FIG.  114   ). In addition, such a portion of the cylindrical portion  402   c  as is on the downstream side, in the N direction (downward), of the accommodating portion side cylindrical portion  402   c   1  is referred to as the opening side cylindrical portion  402   c   2 . 
     The opening  402   a  is provided on the side surface of the opening side cylindrical portion  402   c   2  extending in the direction of the rotational axis A, and faces the outside in the radial direction r of the imaginary circle VC centered on the rotational axis A. The opening  402   a  is structured to be in fluid communication with the inside of the accommodating portion  201  in a state in which the nozzle  402  is coupled to the accommodating portion  201 . The opening  402   a  is provided with seal members  402   a   1  at opposite ends in a direction perpendicular to the rotational axis A as viewed from the opening  402   a.    
     The spring hooking portion  402   e  is on the opposite side of the opening  402   a  in the radial direction r of the imaginary circle VC centered on the rotational axis A, and is provided in a first space S 40  which will be described hereinafter. Further, the spring hooking portion  402   e  is a projection projecting in the direction of the arrow U (upward). 
     As shown in part (b) of  FIG.  116   , the hole portion  402   d  is provided around the rotational axis A 40 . The hole portion  402   d  is provided as a first hole portion  402   d   1 , a second hole portion  402   d   2 , a third hole portion  402   d   3 , and a fourth hole portion  402   d   4 , in this order from the side (nozzle side) of the second end portion in the first direction D 1 . Further, in the direction of the rotational axis A 40 , the space sandwiched between the first hole portion  402   d   1  and the second hole portion  402   d   2  is referred to as a first space S 40 , and the space sandwiched between the second hole portion  402   d   2  and the third hole portion  402   d   3  is referred to as a second space S 41 , and the space sandwiched between the third hole portion  402   d   3  and the fourth hole portion  402   d   4  is referred to as a third space S 42 . 
     The first space S 40  is provided on the opening side cylindrical portion  402   c   2  and penetrates to the opening  402   a . The third space S 42  is provided on the cylindrical portion  402   c   1  on the accommodating portion side. The second space S 41  may be provided in either the opening side cylindrical portion  402   c   2  or the accommodating portion side cylindrical portion  402   c   1 , but it is preferable to provide the second space S 41  in the opening side cylindrical portion  402   c   2  from the standpoint of downsizing. In addition, the third space S 42  is provided with an abutment surface  402   f.    
     The projecting portion  402   b  has the same shape as the projecting portion  202   b  of the nozzle  202  of Embodiment 2, and therefore, detailed description thereof will be omitted. 
     As shown in  FIG.  117   , the movable passage  430  (discharge member) has a hollow substantially rectangular parallelepiped shape, and includes a downward opening  430   a  (discharge opening, first opening), an upward opening  430   b , a pushed portion  430   c , and a spring hooking portion  430   d , a lower seal member  430   e , and an upper seal member  430   f.    
     As shown in part (a) of  FIG.  117   , the downward opening  430   a  is an opening provided on the arrow N direction (downward) side and the arrow V 40  direction (projecting direction) side. Further, a lower seal member  430   e  is provided on the surface provided with the downward opening  430   a  so as to surround the downward opening  430   a.    
     As shown in part (b) of  FIG.  117   , the upward opening  430   b  is an opening provided on the arrow U direction (upward) side and the arrow V 41  direction (retracting direction) side, and communicates with the downward opening  430   a . Further, an upper seal member  430   f  is provided on the surface provided with the upward opening  430   b  so as to surround the upward opening  430   b.    
     The pushed portion  430   c  comprises a first flat pushed surface  430   c   1   a , a first pushed slope  430   c   1   b , a second pushed surface  430   c   2 , and a projecting surface  430   c   3 . The projecting surface  430   c   3  is a surface projecting in the arrow V 41  (retracting direction) of the pushed portion  430   c . In the state in which the toner pack  420  which will be described hereinafter is assembled, the surface remote from the rotational axis A 40  with the projecting surface  430   c   3  as a boundary is the first flat pushed surface  430   c   1   a  and the first pushed slope  430   c   1   b , and the near side is the second pushed surface  430   c   2  (see part (c) of  FIG.  122   ). Further, of the first flat pushed surface  430   c   1   a  and the first pushed slope  430   c   1   b , the surface connected with the projecting surface  430   c   3  is the first pushed slope  430   c   1   b.    
     As shown in part (a) of  FIG.  117   , the spring hooking portion  430   d  is provided on the arrow V 41  direction (retracting direction) side, and is a projection projecting in the direction of arrow N (downward). 
     As shown in part (a) of  FIG.  118   , the cam member  432  includes an arm portion  432   d  and has a generally arc shape as viewed in the rotational axis A 41  direction. A substantially semi-cylindrical push portion  432   a  is provided at one end of the arm portion  432   d , and a hole portion  432   b  and a shaft portion  432   c  are provided at the other end. 
     The hole portion  432   b  is a hole directed in the direction of the arrow N (downward) with the rotational axis A 41  as the center, and comprises a flat locking surface  432   b   1  and a support surface  432   b   2  in the form of a circumferential surface. 
     The shaft portion  432   c  is a substantially cylindrical shaft centered on the rotational axis A 41 , and projects in the direction of the arrow N (downward). 
     As shown in part (b) of  FIG.  118   , the operating member  433  has a substantially flat plate shape including an arm portion  433   a . On one end side of the arm portion  433   a  in the longitudinal direction, a hole portion  433   b  is provided with the rotational axis A 42  as the center and penetrating the arm portion  433   a . The hole portion  433   b  comprises a flat locking surface  433   b   1  and an arc-shaped support surface  433   b   2 . 
     As shown in part (c) of  FIG.  118   , the shaft member  434  has a substantially cylindrical shape centered on the rotational axis A 40 . The shaft member  434  is provided with a flat locking surface  434   a  and a substantially semi-cylindrical support surface  434   b  on the arrow U direction side (upper side), along the rotational axis A 40  (D-cut shape). Further, the shaft member  434  is provided with a flat locking surface  434   c  and a substantially semi-cylindrical support surface  434   d  on the direction (downward) side of the arrow N, along the rotational axis A 40  (D-cut shape). A groove portion  434   e  is provided on the arrow N direction of side with respect to the locking surface  434   a . Further, the end portion of the shaft member  434  on the arrow U direction (upper) side is an upper end  434   f , and the end portion on the arrow N direction (lower) side is a lower end  434   g.    
     (Assembly of Toner Pack) 
     Next, referring to  FIGS.  119 ,  120  and  121   , the assembly of the toner pack  420  according to this embodiment will be described. 
       FIG.  119    illustrates the assembling of the movable passage  430  to the nozzle  402  and the tension spring  431 , part (a) of  FIG.  119    is a perspective view, and part (b) of  FIG.  119    is a sectional view taken along a line X 407 -X 407  in part (b) of  FIG.  114   . 
       FIG.  120    is an illustration of the assembly of the operation mechanism  436  (cam member  432 , operating member  433 , shaft member  434 , E-type retaining ring  435 ) to the nozzle  402 . The states of part (a) of  FIG.  120    to part (d) of  FIG.  120    will be described as appropriate.  FIG.  121    is a perspective view of the toner pack  420 , and is a view as seen from the second end side (nozzle side) in the first direction D 1 . Further, part (a) of  FIG.  121    is a view as seen from the opening  402   a  side of the nozzle  402 , and part (b) of FIG.  121  is a view as seen from the side opposite to the opening  402   a . The accommodating portion  201  and the pack-side shutter  203  are not shown. 
     First, as shown in part (a) of  FIG.  119   , the tension spring  431  and the movable passage  430  are assembled to the nozzle  402 . The movable passage  430  is inserted into the opening  402   a  of the nozzle  402  in the arrow V 41  direction (retracting direction) with such an attitude that the downward opening  430   a  faces in the arrow N direction (downward) and is on the arrow V 40  (projecting direction) side. The arrow V 40  direction and the arrow V 41  direction are directions perpendicular to the rotational axis A or the radial directions r. At this time, one end of the tension spring  431  is in a state of being hooked on the spring hooking portion  430   d  of the movable passage  430  shown in part (b) of  FIG.  119   . After the movable passage  430  is inserted into the opening  402   a  of the nozzle  402 , the other end of the tension spring  431  is hooked on the spring hooking portion  402   e  of the nozzle  402 , so that the assembly of the movable passage  430  is completed. 
     Next, as shown in part (a) of  FIG.  120   , the operating member  433  and the shaft member  434  are assembled to the nozzle  402 . The operating member  433  is inserted into the third space S 42  of the nozzle  402  in the direction of an arrow V 42  until the rotational axis A 41  is aligned with the rotational axis A 40 . Thereafter, the shaft member  434  is inserted into the first hole portion  402   d   1  relative to the nozzle  402  from the upper end  434   f  side in the direction of the arrow U. Then, the upper end  434   f  of the shaft member  434  passes through the second hole portion  402   d   2  and the third hole portion  402   d   3  of the nozzle  402  in order, and thereafter is inserted into the hole portion  433   b  of the operating member  433  in the arrow U direction. At this time, It is inserted such that the locking surface  434   a  of the shaft member  434  and the locking surface  433   b   1  of the operating member  433  are engaged with each other and such that the support surface  434   b  of the shaft member  434  and the support surface  433   b   2  of the operating member  433  are engaged with each other. By the engagement between the locking surface  434   a  of the shaft member  434  and the locking surface  433   b   1  of the operating member  433 , the operating member  433  and the shaft member  434  can be integrally rotated around the rotational axis A 40 . 
     Then, when the shaft member  434  is further inserted in the arrow U direction (upward) relative to the nozzle  402 , the upper end  434   f  is in the fourth hole portion  402   d   4  and the lower end  434   g  is in the second hole portion  402   d   2  as shown in part (b) of  FIG.  120   . 
     Next, the cam member  432  is assembled to the nozzle  402  from this state. The cam member  432  is inserted into the first space S 40  of the nozzle  402  in the direction of an arrow V 43  until the rotational axis A 42  is aligned with the rotational axis A 40 . As described above, since the lower end  434   g  of the shaft member  434  is inserted until it penetrates into the second hole portion  402   d   2  of the nozzle  402 , the shaft member  434  does not exist in the first space S 40  of the nozzle  402 . By this, the cam member  432  can be inserted into the first space S 40  of the nozzle  402  without interfering with the shaft member  434 . Then, as shown in part (c) of  FIG.  120   , the cam member  432  is in the first space S 40  of the nozzle  402 . 
     Next, as shown in part (c) of  FIG.  120   , the cam member  432  is engaged with the nozzle  402 , and the shaft member  434  is engaged with the cam member  432 . The shaft portion  432   c  of the cam member  432  is inserted into the first hole portion  402   d   1  in the N direction (downward) of the arrow relative to the nozzle  402 . At this time, the shaft portion  432   c  of the cam member  432  is rotatably supported around the rotational axis A 40  relative to the first hole portion  402   d   1  of the nozzle  402 . In addition, the shaft member  434  is inserted into the hole portion  432   b  of the cam member  432  in the arrow N direction (downward). At this time, the locking surface  434   c  of the shaft member  434  and the locking surface  432   b   1  of the cam member  432  are engaged with each other, and the support surface  434   d  of the shaft member  434  and the support surface  432   b   2  of the cam member  432  are engaged with each other. By The engagement between the locking surface  434   c  of the shaft member  434  and the locking surface  432   b   1  of the cam member  432 , the cam member  432  and the shaft member  434  can be integrally rotated around the rotational axis A 40 . Further, in the direction (downward) of the arrow N, the cam member  432  is constrained from moving relative to the nozzle  402 , and the shaft member  434  is constrained from moving relative to the cam member  432 . Therefore, the shaft member  434  is in a state where the movement thereof is restricted relative to the nozzle  402  in the direction (downward) of the arrow N. 
     Finally, as shown in part (d) of  FIG.  120   , the E-shaped retaining ring  435  is assembled to the shaft member  434 . The groove portion  434   e  of the shaft member  434  is provided so as to be close to the third hole portion  402   d   3  in the second space S 41  of the nozzle  402 . By engaging the E-shaped retaining ring  435  with the groove portion  434   e  of the shaft member  434 , the movement of the shaft member  434  relative to the nozzle  402  in the arrow U direction is restricted. 
     Through the above-described assembling operations, as shown in  FIG.  121   , the movable passage  430 , the tension spring  431 , and the operation mechanism  436  are assembled to the nozzle  402 , the cam member  432  and the operating member  433  can rotate integrally with the shaft member  434  around the rotational axis A 40 , as described above, and therefore, when the operating member  433  is rotated in the rotational direction K 40 , the cam member  432  also rotates in the direction K 40 . 
     Thereafter, the assembly of the toner pack  420  is completed by assembling the accommodating portion  201  and the pack side shutter  203  to the nozzle  402 . 
     (Operation of Toner Pack) 
     Next, referring to  FIGS.  122  and  123   , the operation of the toner pack  420  when the operating member  433  is operated will be described. 
       FIG.  122    shows a state in which the movable passage  430  is in the second position stored in the nozzle  402 , and part (a) thereof to part (c) thereof show a state in which the pack-side shutter  203  is in the closed position (d), and part (d) thereof to (f) thereof show a state in which the pack side shutter  203  is in the open position. Further, in  FIG.  122   , part (a) and part (d) are perspective views, Part (b) and part ( e ) are sectional views taken along a line X 407 -X 407  of part (b) of  FIG.  114    in the respective states, and part (c) the cross-section of view taken along a line X 401 -X 401  of b) of part (b) of  FIG.  122   , and part (f) is a cross-sectional view taken along a line X 402 -X 402  of part ( e ) of this Figure. 
       FIG.  123    shows the operation of the movable passage  430  by operating the operating member  433 , and part (a) of this Figure to (c) thereof shows the state in which where the movable passage  430  is in the position projecting most from the nozzle  402  (the most projecting position), and parts (d) to (f) of these Figure shows a state in which the movable passage  430  is in the first position projecting from the nozzle  402 . Further, in  FIG.  123   , parts (a) and (d) of this Figure are perspective views, parts (b) and ( e ) are sectional views taken along a line X 407 -X 407  of part (b) of  FIG.  114    in the respective states, part (c) is a cross-sectional view taken along a line X 403 -X 403  of part (b) of this Figure, and part (f) is a cross-section taken along a line X 404 -X 404  of part ( e ) of this Figure. 
     Further, in  FIGS.  122  and  123   , the cut surfaces of the pack-side shutter  203  and the movable passage  430  are shaded for better illustration. 
     The description will first be made as to a state in which the pack-side shutter  203  shown in part (a) of  FIG.  122    is in the closed position, and the movable passage  430  is in the second position (retracting position). The operating member  433  projects outward from the nozzle  402  in the radial direction r of the imaginary circle VC centered on the rotational axis A. This makes it easier for the user to operate the operating member  433 . 
     Further, as shown in part (b) of  FIG.  122   , the movable passage  430  receives a force F 400  imparted by the tension spring  431  in the direction of arrow V 41  (retracting direction) relative to the nozzle. The force F 400  maintains the movable passage  430  in a second position housed in the nozzle  402 . In addition, in the state of being in the second position, the downward opening  430   a  of the movable passage  430  is closed in the arrow N direction (downward), and the upward opening  430   b  is closed in the arrow U direction (upward). In this embodiment, the upward opening  430   b  of the movable passage  430  is closed with respect to the accommodating portion  201  (see  FIG.  114   ) on the arrow U direction (upward) side of the nozzle  402 , but it may be open. 
     Further, as shown in part (c) of  FIG.  122   , the movable passage  430  overlaps with the pack side shutter  203  in the rotational axis A direction, and also overlaps with the rotational direction K. In other words, the movable passage  430  overlaps with the pack side shutter  203  as viewed in the radial direction r. That is, the movable passage  430  is hidden by the pack-side shutter  203 , thereby preventing the user from touching the movable passage  430 . Further, the outflow of the toner, to the outside, which has entered the inside of the nozzle  402  from the accommodating portion  201  is prevented by the upper seal member  430   f  (see part (b) of  FIG.  122   ) provided in the movable passage  430 . And, the cam member  432  is in contact with the first flat pushed surface  430   c   1   a  of the movable passage  430 . 
     When the pack-side shutter  203  is rotated in the rotational direction K from this position to the open position, the state as shown in part (d) of  FIG.  122    is provided. Further, as shown in part ( e ) of  FIG.  122    and part (f) of  FIG.  122   , the movable passage  430  is exposed from the pack side shutter  203  and becomes able to move in the arrow V 40  direction (projecting direction). 
     That is, when the pack side shutter  203  is in the open position, the movable passage  430  is as follows. The movable passage  430  projects from the opening  402   a  of the nozzle  402  in the direction of the arrow V 40 , and is movable between a first position where the downward opening  430   a  is exposed to the outside of the toner pack  420  and a second position retracted from the first position in the direction of the arrow V 41 . 
     As shown in part (f) of  FIG.  122   , in order to move the movable passage  430  in the arrow V 40  direction (projecting direction), a force is applied to the operating member  433  to rotate in the rotational direction K 40 . Since the cam member  432  rotates integrally with the operating member  433 , the push portion  432   a  of the cam member  432  applies a force F 401  to the first pushed surface  430   c   1   a  of the movable passage  430  in the arrow V 40  direction (projecting direction). By the force F 401 , the movable passage  430  moves in the arrow V 40  (projecting direction) against the force F 402  in the arrow V 41  direction (retracting direction) produced by the tension spring  431  (see part (b) of  FIG.  122   ). At this time, the user carries out of this operation while feeling the load of the moment M 400  in the direction opposite to the rotational direction K 40  by the force F 402 . 
     Then, when the cam member  432  is further rotated in the rotational direction K 40 , the push portion  432   a  of the cam member  432  pushes the first flat pushed surface  430   c   1   a  and the first pushed slope  430   c   1   b  of the movable passage  430  in this order, and as shown in part (c) of  FIG.  123   , it comes into contact with the projecting surface  430   c   3  of the movable passage  430 . At this time, the movable passage  430  is at the position most projecting from the nozzle  402  (most projecting position). Also at this time, the user carries out the operation while feeling the load of the moment M 400  in the direction opposite to the rotational direction K 40  by the force F 403  produced by the tension spring  431 . 
     In the state where the movable passage  430  is in the most projecting position, the downward opening  430   a  of the movable passage  430  is projected from the opening side cylindrical portion  402   c   2  of the nozzle  402  in the arrow V 40  direction (projecting direction), as shown in part (b) of  FIG.  123   , and it becomes opened in the direction (downward) of the arrow N. The upward opening  430   b  of the movable passage  430  is opened with respect to the accommodating portion  201  (see  FIG.  114   ) on the arrow U direction side (above) of the nozzle  402 . 
     When the operating member  433  is further rotated in the rotational direction K 40  from this position, the push portion  432   a  of the cam member  432  abuts on the second pushed surface  430   c   2  of the movable passage  430  as shown in part (f) of  FIG.  123   . In this state, the tension spring  431  (see part ( e ) of  FIG.  123   ) causes the second pushed surface  430   c   2  of the movable passage  430  to apply a force F 404  to the cam member  432 . At this time, the position and direction of the second pushed surface  430   c   2  of the movable passage  430  are set so that the moment M 401  produced in the cam member  432  by the force F 404  is in the same direction as the rotational direction K 40 . The cam member  432  is rotated in the rotational direction K 40  by the moment M 401 . The operating member  433  rotated in the rotational direction K 40  together with the cam member  432  abuts on the abutment surface  402   f  of the nozzle  402 , and the rotation is stopped (restricted). That is, the rotation, integral with the operating member  433 , of the cam member  432  in the rotational direction K 40  is also stopped (restricted). Therefore, the movable passage  430  is constrained from moving in the arrow V 41  direction (retracting direction) by the cam member  432  which is at rest (restricted) as described above. By this, the operation of the operating member  433  is completed. The position of the movable passage  430  at this time is the second position (projecting position). 
     When the movable passage  430  moves from the most projecting position to the first position, the movable passage  430  moves slightly in the V 41  direction (evacuation direction), but the amount of movement is so small that the opening  430   a  of the movable passage  430  remains open in the direction of the arrow N (downward). Similarly, the upward opening  430   b  of the movable passage  430  remains open to the accommodating portion  201  (see  FIG.  114   ) placed in the downstream side on the arrow U direction side of (above) the nozzle  402 . 
     Further, as described above, when the user operates the operating member  433  in the rotational direction K 40  the user carries out the operation while feeling the moment M 400  in the direction opposite to the rotational direction K 40  (see part (d) of  FIG.  122    and part (a) of  FIG.  123   ), during the movable passage  430  being between the second position and the most projecting position. Thereafter, when the movable passage  430  is positioned at the second position, the movement is switched to the moment M 401  in the rotational direction K 40  opposite to the moment M 400  (see part (d) of  FIG.  123   ), and therefore, the user recognizes the load reduction. Then, the user can recognize the completion of the operation of the operating member  433  by recognizing the load reduction. 
     When the user returns the movable passage  430  from the second position to the first position, the operation reverse to the above-described operation is be performed. As shown in part (d) of  FIG.  123   , the operating member  433  may be rotated in the rotational direction L 40 , which is the direction opposite to the rotational direction K 40 . 
     The foregoing is the operation of the toner pack  420 . 
     (Mounting and Dismounting of Toner Pack) 
     Referring to  FIGS.  124  to  126    the operation of mounting and dismounting the toner pack  420  to and from the mounting portion  206  will be described. The operation of inserting and removing the toner pack  420  relative to the mounting portion  206  is the same as that of Embodiment 2, the description thereof will be omitted. 
       FIG.  124    shows a process of inserting the toner pack  420  into the mounting portion  206  and operating the operating lever  208  and the operating member  433 . In  FIG.  124   , part (a) shows a state in which the operating lever  208  is in the closed position, part (b) shows a state in which the operating lever  208  is in the open position, and part (c) shows a state in which the operating member  433  is further operated to place the movable passage  430  in the second position. 
       FIG.  125    is a sectional view in a state in which the toner pack  420  is mounted on the mounting portion  206  and the operating lever  208  is in the open position, and part (a) of  FIG.  125    is a sectional view taken along the rotational axis A and the arrow V 40  (projection direction), and part (b) of  FIG.  125    is a cross-section taken along a line X 405 -X 405  of part (a) of  FIG.  125   . 
       FIG.  126    is a sectional view when the operating member  433  is operated to move the movable passage  430  to the second position, part (a) of this Figure is a sectional view taken along the rotational axis A and the arrow V 40  (projecting direction), and part (b) is a cross-section taken along a line X 406 -X 406  of part (a). 
     In  FIGS.  125  and  126   , the cut surfaces of the pack side shutter  203  and the movable passage  430  is shaded. 
     In the mounting operation of the toner pack  420  on the mounting portion  206 , after inserting the toner pack  420  into the mounting portion  206 , the operating lever  208  is first rotated in the rotational direction D as shown in  FIG.  124   , and then the operating member  433  is rotated in the direction of an arrow K 40 . 
     First, when the operating lever  208  is rotated in the rotational direction D after being inserted into the mounting portion  206  of the toner pack  420 , the state shown in  FIG.  125    is provided. In this state, as shown in part (a) of  FIG.  125   , the movable passage  430  is in the second position. At this time, the downward opening  430   a  of the movable passage  430  is closed in the direction of the arrow N (downward) with respect to the opening side cylindrical portion  402   c   2  of the nozzle  402 , the toner in the accommodating portion  201  (see  FIG.  114   ) cannot reach the apparatus-side opening  217   a  of the second frame  217  through the nozzle  402 . 
     Further, as shown in part (a) of  FIG.  125    and part (b) of  FIG.  125   , the apparatus-side seal  211  covers the periphery of the opening  402   a  of the nozzle  402 . 
     Next, when the operating member  433  is operated and the movable passage  430  is moved to the second position, the state shown in  FIG.  126    is provided. 
     In this state, as shown in part (a) of  FIG.  126   , the downward opening  430   a  of the movable passage  430  projects from the opening side cylindrical portion  402   c   2  of the nozzle  402  in the arrow V 40  direction (projecting direction) and is opened in the arrow N direction (downward). Then, the movable passage  430  enters the inside of the first frame  207  of the mounting portion  206 , and the downward opening  430   a  of the movable passage  430  is placed inside the first frame  207 . 
     By this, the toner in the accommodating portion  201  (see  FIG.  114   ) can reach the apparatus-side opening  217   a  of the second frame  217  by way of the nozzle  402  and the movable passage  430 , as indicated by the thick dotted arrow in the Figure. Further, as shown in part (a) of  FIG.  126    and part (b) of  FIG.  126   , the apparatus-side seal  211  covers the periphery of the opening  402   a  of the nozzle  402  and the periphery of the movable passage  430  to prevent toner scattering. 
     This completes the mounting operation of the toner pack  420  on the mounting portion  206 . 
     The removal of the toner pack  420  from the mounting portion  206  is performed in the reverse process of mounting the toner pack  420  on the mounting portion  206 . That is, the operating member  433  is rotated in the rotational direction L 40  from the state of part (c) of  FIG.  124   , and then the operating lever  208  is rotated in the rotational direction E from the state of part (b) of  FIG.  124   . The detailed operation of the movable passage  430  and the like at this time is merely the opposite of the mounting of the toner pack  420  on the mounting portion  206 , and the description thereof will be omitted. 
     As described above, in the toner pack  420  of this embodiment, the nozzle  402  is provided with the movable passage  430 , and the movable passage  430  movable between the first position stored in the nozzle  402  and the projecting second position. 
     By this, when the movable passage  430  is in the first position, the pack-side shutter  203  not only closes the opening  402   a  of the nozzle  402 , but also closes the downward opening  430   a  of the movable passage  430 . This makes it possible to more reliably prevent the toner from leaking out from the nozzle  402  of the toner pack  420  to the outside. 
     Further, when the toner is replenished from the toner pack  420  to the toner accommodating chamber  36  of the developer container  32 , the toner can be discharged from a relatively deeper position of the mounting portion  206 . This makes it possible to more reliably prevent toner from scattering out during replenishment. 
     Embodiment 5 
     Next, referring to  FIGS.  127  to  141   , another structure will be described. The same points as those of the above-described embodiments and modified examples will be omitted. In particular, of the elements disclosed in this embodiment, those corresponding to the members described in the above-described embodiments are assigned the same names as those in the above-described embodiment, and only the points different from those in the above-mentioned embodiment will be described. 
     Referring to  FIGS.  127 ,  128 ,  129  and  130   , the structure of the toner pack  520  will be described.  FIG.  127    is a perspective view of the toner pack  520  having the structure of this embodiment.  FIG.  128    is an exploded perspective view of the toner pack  520 .  FIG.  129    is a partially exploded perspective view as seen from the opposite direction of the exploded perspective view of  FIG.  128   .  FIG.  130    is a partially exploded perspective view as seen from the opposite direction of the exploded perspective view of  FIG.  129   . 
     As shown in  FIGS.  127  and  128   , the toner pack  520  includes an accommodating portion  501  (first accommodating portion) for accommodating toner, a seal support member  530 , a toner seal  531 , a connection ring  532 , a nozzle  502 , and a pack side shutter  203 . 
     As shown in  FIG.  128   , in the first direction D 1 , the accommodating portion  501  is provided at the first end portion, and on the second end portion side opposite to the first end portion in the first direction D 1 , the seal supporting member  530 , the toner seal  531 , the connection ring  532 , the nozzle  502 , and the pack-side shutter  203  are provided. As in Embodiment 2, the accommodating portion  501  includes a pouch formed by pouch processing of a flexible polypropylene sheet. The accommodating portion  501  is not limited to the pouch, and may be a resin bottle or a container made of paper or vinyl. 
     As shown in  FIGS.  128  and  129   , the seal support member  530  has a generally cylindrical shape centered on the rotational axis A (central axis), and includes an end surface  530   a  an outer cylindrical portion  530   b  in this order from the first end side in the first direction D 1 , and a mounting surface  530   c  on the side opposite to the end surface  530   a . The mounting surface  530   c  is provided on the outside of the outer cylindrical portion  530   b  and has a flat plate shape perpendicular to the rotational axis A. On the mounting surface  530   c , a through hole  530   f  having an axis parallel to the rotational axis A and an oblong hole  530   g  are provided at positions substantially symmetric with respect to the rotational axis A. 
     Further, the inner cylinder  530   d  is arranged inside the outer cylindrical portion  530   b . The end surface  530   a  and the inner cylinder  530   d  are connected by a connection surface  530   e . The connection surface  530   e  is an inclined surface that is inclined so as to be away from the rotational axis A as goes toward the first end side in the first direction D 1  with the rotational axis A as the center. In addition, in the first direction D 1  of the inner cylinder  530   d , an end surface  530   h  is provided on the second end side (see  FIG.  128   ). The end surface  530   h  is a flat surface substantially perpendicular to the rotational axis A, and is placed slightly on the first end side in the first direction D 1  with respect to the mounting surface  530   c.    
     The connection ring  532  has a substantially cylindrical shape centered on the rotational axis A, and includes an inner peripheral surface  532   a , an outer peripheral portion  532   b , an end surface  532   c  placed on the first end side in the first direction D 1   a  second end side end surface  532   d  placed on the second end side in the first direction D 1 . In addition, a thread groove portion  532   e  is provided at the inner peripheral surface  532   a  of the connection ring  532 . 
     Further, on the end surface  532   c , bosses  532   f  and  532   g  having axes parallel to the rotational axis A are provided at substantially symmetric positions about the rotational axis A so as to project toward the first end side in the first direction D 1 . 
     An opening  532   h  is provided on the first end side, in the first direction D 1 , of the inner peripheral surface  532   a.    
     A toner seal  531  is mounted closely to the end surface  532   c  so as to seal the opening  532   h  by adhesion or the like. In addition, the seal support member  530  is mounted to the connection ring  532  substantially coaxially from the first end side in the first direction D 1 . The through hole  530   f  and the oblong hole  530   g  of the seal support member  530  are engaged with the boss  532   f  and  532   g  of the connection ring  532 , respectively, and the mounting surface  530   c  of the seal support member  530  is mounted by adhesion or the like on the end surface  532   c  with the toner seal  531  sandwiched therein. 
     Further, the opening  501   a  (see  FIG.  128   ) of the accommodating portion  501  is connected to the outer peripheral portion  532   b  of the connection ring  532  without a gap by adhesion or the like. In this manner, the toner inside the accommodating portion  501  is sealed by the connection ring  532  and the toner seal  531 . 
     Further, as shown in  FIG.  130   , the second end side end surface  532   d  of the connection ring  532  in the first direction D 1  is provided with a recess  532   k  recessed toward the first end side in the first direction D 1 . The recess portion  532   k  is recessed in a circumferential shape and is arranged substantially coaxially with the rotational axis A. A ring seal  533 , of an elastic member having a substantially cylindrical shape, is mounted to the recess  532   k  so as to be fitted from the second end side in the first direction D 1 , and is fixed to the connection ring  532  by adhesion or the like. 
     Further, the nozzle  502  is connected to the second end side in the first direction D 1  of the connection ring  532 . 
     Referring to  FIG.  131   , the shape of the nozzle  502  will be described.  FIG.  131    is a perspective view of the nozzle  502 . As shown in  FIG.  131   , the nozzle  502  has a substantially cylindrical shape centered on the rotational axis A, and includes an end surface  502   p , a thread ridge portion  502   r , a disk portion  502   s , a side surface  502   c  and a projecting portion  502   b , in this order from the first end portion side in the first direction D 1 . 
     The thread ridge portion  502   r  of the nozzle  502  has a shape which is capable of meshing engagement with the thread groove portion  532   e  provided on the inner peripheral surface  532   a  of the connection ring  532 , and the nozzle  502  and the connection ring  532  are connected by the threading therebetween. The disk portion  502   s  has a disk shape of a generally flat plate substantially coaxial with the rotational axis A, and has an outer diameter larger than that of the thread ridge portion  502   r.    
     Further, the pack side shutter  203  is mounted to the nozzle  502 . 
     The pack-side shutter  203  has the same shape as that of Embodiment 2, and therefore, the description thereof will be omitted. 
     Further, the connection method of the pack side shutter  203  and the nozzle  502  has the same structure as that of Embodiment 2, and therefore, the description thereof will be omitted. 
     Next, referring to  FIGS.  131  and  132   , the shape of the nozzle  502  will be described in detail. 
     Part (a) of  FIG.  132    is a sectional view of the nozzle  502  taken along a line X 501 -X 501  of a side view part (c) of  FIG.  132   . Part (b) of  FIG.  132    is a detailed view of a DT portion of part (a) of  FIG.  132   . Part (c) of  FIG.  132    is a side view of the toner pack  520  showing the position of the line along which the sectional view of part (a) of  FIG.  132    is taken. 
     As shown in  FIG.  131    and part (a) of  FIG.  132   , when the toner pack  520  is in fresh and unused state, the nozzle  502  having this structure does not have anything that corresponds to the discharge opening (discharge opening  202   a  of Embodiment 2). At a position corresponding to the discharge opening of the side surface  502   c  of the nozzle  502 , a pull tab  502   k  projecting outward in the radial direction r of the imaginary circle VC centered on the rotational axis A is mounted. Therefore, the recess  502   n  is provided inside the nozzle  502  similarly to the passage through which the toner of Embodiment 2 passes, but it is not fluid communication with the side surface  502   c  of the nozzle  502 . Here, the pull tab  502   k  is integrally formed with the nozzle  502 . That is, the pull tab  502   k  is connected to the side surface  502   c  of the nozzle  502 . The pull tab  502   k  has a substantially cylindrical shape, and the cylindrical axis is substantially parallel to the rotational axis A. The pull tab  502   k  has a cylindrical portion  502   k   1  and a connecting portion  502   k   2 . The connecting portion  502   k   2  has a substantially plate-like shape which connects the side surface  502   c  of the nozzle  502  and the pull tab  502   k  with each other. Further, the side surface  502   c  is provided with a recess  502   m  which surrounds the connecting portion  502   k   2  and is recessed inward from the side surface  502   c.    
     As shown in part (b) of  FIG.  132   , the recess  502   n  is provided on the rotational axis A side of the recess  502   m  with a wall portion  502   t  interposed therebetween. The wall portion  502   t  is a partially thin due to the provision of the recess  502   m  of the side surface  502   c.    
     (User Operation) 
     Next, referring to  FIGS.  133 ,  134 , and  135   , the user&#39;s operation will be described. 
       FIG.  133    is a schematic perspective view illustrating a first operation of the user.  FIG.  134    is a side view illustrating a second operation of the user.  FIG.  135    is a side view illustrating a third operation of the user. 
       FIG.  136    is a sectional view taken along a line X 501 -X 501  shown in part (c) of  FIG.  132    of  FIG.  135   . 
     As shown in  FIG.  133   , the user pulls the pull tab  502   k  in the direction of an arrow V 50 . Then, the thin wall portion formed by the recess  502   m  breaks from the portion close to the connecting portion  502   k   2 , and the wall portion  502   t  is separated from the nozzle  502  along the shape of the recess  502   m . In this manner, as shown in part (a) of  FIG.  134   , a discharge opening  502   a  in fluid communication with the recess  502   n  inside the nozzle  502  is formed on the side surface  502   c . That is, the discharge opening  502   a  of the nozzle  502  is structured to be formed by breaking the wall portion  502   t  which is a part of the side surface  502   c  extending in the direction of the rotational axis A of the nozzle  502  and separating it from the nozzle  502 . 
     At this time, as described above, the toner stored in the accommodating portion  501  is sealed by the connection ring  532  and the toner seal  531  so that the toner does not flow out through the discharge opening  502   a.    
     Next, as shown in part (b) of  FIG.  134   , the user rotates the pack-side shutter  203  relative to the nozzle  502  in the direction of the arrow L, and by this operation, the discharge opening  502   a  is sealed by the pack-side seal  205 . 
     Next, as shown in  FIG.  135   , the user rotates the connection ring  532  with respect to the nozzle  502  in the direction of the arrow L. The connection ring  532  performs relative movement in the direction of the arrow N along the thread groove portion  532   e  provided on the inner peripheral surface  532   a  substantially coaxial with the nozzle  502 , while rotating in the direction of arrow L as shown in part (a) of  FIG.  135   , part (b) of  FIG.  135    to part (c) of  FIG.  135   . The connection ring  532  moves until the second end side end surface  532   d  and the disk portion  502   s  of the nozzle  502  abut to each other (part (c) of  FIG.  135   ). 
     At this time, as shown in part (c) of  FIG.  136    and part (d) of  FIG.  136   , the end surface  502   p  of the nozzle  502  contacts the toner seal  531  while rotating relatively thereto, and breaks through the toner seal  531 , so that the toner sealing state is broken. 
     Referring to  FIGS.  136  and  137   , the state of the above-described toner seal  531  will be described. Part (a) of  FIG.  137    shows a state before the toner seal  531  is torn, and part (b) of  FIG.  137    shows a state after the toner seal  531  is torn. 
     As shown in part (a) of  FIG.  137   , the toner seal  531  is provided with a precut portion  531   a  in advance. The precut portion  531   a  is formed radially around the rotational axis A. 
     As shown in part (d) of  FIG.  136   , the end surface  502   p  of the nozzle  502  abuts to the toner seal  531 , which is thereby torn along the precut portion  531   a . As shown in part (d) of  FIG.  136    and part (b) of  FIG.  137   , the torn toner seal  531  is deformed so as to be folded between the outer cylindrical portion  530   b  and the inner cylinder  530   d  of the seal support member  530 . In this manner, the toner seal  531  arranged so as to seal the opening  532   h  (part (b) of  FIG.  136   ) of the connection ring  532  is removed, and the toner seal by the toner seal  531  is released. 
     Thus, the toner sealing state by the toner seal  531  is released, the toner of the toner pack  520  flows into the nozzle  502 , and is sealed by the pack side seal  205  described above. 
     Further, at this time, as shown in part (d) of  FIG.  136   , the ring seal  533  adhered to the connection ring  532  is compressed between the recess  532   k  of the connection ring  532  and the disk portion  502   s  of the nozzle  502  in the first direction D 1 . In this manner, the toner is sealed between the connection ring  532  and the nozzle  502 . 
     Thereafter, the user mounts the toner pack  520  on the mounting portion  206  of the image forming apparatus  1  by the same operation as in Embodiment 2. Further, the operating lever  208  is rotated in the direction of arrow D, and the attachment to the image forming apparatus  1  is completed. The structure is the same as that of Embodiment 2, and therefore, the details will be omitted. In this manner, the toner of the accommodating portion  501  is replenished into the toner accommodating chamber  36  of the developer container  32  through the discharge opening  502   a  of the nozzle  502  as in Embodiment 2. 
     After the toner is replenished, the discharge opening  502   a  is resealed by rotating the operating lever  208  in the direction of arrow E, and the toner pack  520  is permitted to be removed from the apparatus main assembly as in Embodiment 2. The structure is the same as that of Embodiment 2, and therefore, the description thereof will be omitted. 
     In the foregoing description, the toner sealed state is released by breaking the toner seal  531 . On the other hand, the toner sealing state may be released by the user manually pulling out the toner seal to the outside. 
     Referring to  FIGS.  138 ,  139 ,  140 , and  141    this structure will be described in detail. 
       FIG.  138    is an external view of a toner pack  5120  in which the toner seal is pulled out to the outside by the user.  FIG.  139    is an exploded perspective view illustrating the mounting of the toner seal of the toner pack  5120 .  FIG.  140    is a partially exploded perspective view as seen in the direction opposite to that of the perspective view of  FIG.  139   .  FIG.  141    is sectional views of the toner pack  5120 . 
     As shown in  FIG.  138   , the toner pack  5120  is provided with a toner seal  534  and a pull tab  535  on the nozzle portion in the above-described structure. 
     The toner seal  534  has a thin film-like band shape, and is arranged substantially perpendicular to the rotational axis A. Further, the toner seal  534  is fixed to the first nozzle portion  5102 , which will be described hereinafter, by adhesion or the like. Further, a pull tab  535  is connected by adhesion or the like to the toner seal  534  at the side opposite from the connecting portion relative to the first nozzle portion  5102 . The pull tab  535  has a hollow substantially cylindrical shape and has an axis substantially perpendicular to the toner seal  534 . 
     As shown in  FIG.  139   , in the nozzle of this structure, a second nozzle portion  537 , a seal cap  536 , and a first nozzle portion  5102  are arranged in this order from the first end portion side in the first direction D 1 . 
     The second nozzle portion  537  has a generally hollow cylindrical shape, and is arranged substantially coaxially with the rotational axis A. The second nozzle portion  537  includes a first end side end surface  537   e , a first cylindrical portion  537   b  placed substantially coaxially with the rotational axis A, a second cylindrical portion  537   c  placed substantially coaxially with the rotational axis A and having a larger outer diameter than the first cylindrical portion, and a second end side end surface  537   d , in the order named from the first end side in the first direction D 1 . 
     Further, as shown in  FIG.  140   , the second end side end surface  537   d  is provided with a recess  537   a  recessed toward the first end side in the first direction D 1 , a cylindrical recess  537   f , and an oval cylindrical recess  537   g . The seal cap  536  is fitted into the recess  537   a  from the second end side in the first direction D 1 . 
     The seal cap  536  has a substantially flat plate shape and is placed perpendicular to the rotational axis A. The seal cap  536  has a base portion  536   a  on the first end side in the first direction D 1 , and is provided with a plurality of fin portions  536   b  projecting toward the second end side in the first direction D 1  which is the opposite side. The fin portions  536   b  have a generally flat plate shape extending substantially parallel to the rotational axis A, and are arranged at equal intervals toward the outside in the radial direction r of the imaginary circle VC centered on the rotational axis A. The seal cap  536  is made of an elastic material such as an elastomer, and in particular, the plurality of fin portions  536   b  are structured to be freely bent in the radial direction r of the imaginary circle VC centered on the rotational axis A. 
     As shown in  FIG.  139   , the first nozzle portion  5102  has a generally cylindrical shape and is placed substantially coaxially with the rotational axis A. The first nozzle portion  5102  is provided with a first end side end surface  5102   d , a side surface  5102   c  perpendicular to the rotational axis A, and a projecting portion  5102   b , in this order from the first end side in the first direction D 1 . The side surface  5102   c  and the projecting portion  5102   b  have the same structures as the above-mentioned side surface  502   c  and the projecting portion  502   b , respectively, and therefore, the description thereof will be omitted. 
     The first end side end surface  5102   d  is provided with an opening  5102   a  leading to a passage through which the toner of Embodiment 2 passes. In addition, on the end side surface  5102   d  is provided with, two bosses  5102   f  and  5102   g  projecting toward the first end side in the first direction D 1  at positions substantially symmetrically with respect to the rotational axis A. 
     As shown in  FIG.  139   , a toner seal  534  is fixed on the first end side end surface  5102   d  so as to cover the opening  5102   a  by adhesive or the like. The toner seal  534  is bonded so as to cover the opening  5102   a , and then folded back so as to overlap the bonded portion. 
     Thereafter, the second nozzle portion  537  is mounted, coaxially with the rotational axis A, to the first end surface  5102   d  from the first end side in the first direction D 1 , with the seal cap  536  mounted. At this time, positioning is effected by carrying out the mounting so that the two bosses  5102   f  and  5102   g  of the first nozzle portion  5102  fit into the cylindrical recess  537   f  and the oval cylindrical recess  537   g  of the second nozzle portion  537 , respectively. The second nozzle portion  537  is mounted to the first nozzle portion  5102  by adhesive or the like, and the seal cap  536  is mounted in the manner as if the plurality of fin portions  536   b  trample the folded toner seal  534 . In this manner, the toner seal is effected so that the seal cap  536  fills the space between the first nozzle portion  5102 , the second nozzle portion  537 , and the toner seal  534 . 
     As shown in part (a) of  FIG.  141   , when the user pulls out the pull tab  535  toward the outside in the radial direction r of the imaginary circle VC centered on the rotational axis A, the toner seal  534  is dismounted from the first nozzle portion  5102  is removed from the toner pack  5120  and separated from the toner pack  5120 . At this time, as shown in part (b) of  FIG.  141   , the plurality of fin portions  536   b  of the seal cap  536  press the toner seal  534  in the first direction D 1 , and after the toner seal  534  is pulled out, the plurality of fin portions  536   b  abuts against the first end side end surface  5102   d  of the first nozzle portion  5102 , so that the toner is sealed between the first nozzle portion  5102  and the second nozzle portion  537 . 
     With the above-described structure, the toner seal is released by the user pulling out the toner seal  534  to the outside. 
     Further, in the above-described plurality of structures, the use is made with the toner seals  531  and  534  has been described, it is also possible to employ a structure in which the toner seals  531  and  534  are not provided, and instead the instruction manual or the like tells that the pull tab  502   k  of the nozzle  502  is to be pulled out by the user with the second end side of the first direction D 1  being made upward in advance that the is peeled off. 
     Embodiment 6 
     Next, referring to  FIGS.  142  to  147   , Embodiment 6 will be described below. In this embodiment, as compared with Embodiment 3, the second restriction releasing portion is movable relative to the first restriction releasing portion between a first position where the first slope and the second slope aligned with each other, and a second position where it is rotated about the rotational axis A. The description on the same points as in the above-described embodiment will be omitted. In particular, of the elements disclosed in this embodiment, those corresponding to the members described in Embodiments 2 and 3 are assigned the same names as those of the members of Embodiments 2 and 3, and only the points different from these Embodiments will be described. 
     (Toner Pack Structure) 
     Referring to  FIGS.  142  to  144   , a toner pack  620  in this embodiment will be described.  FIG.  142    is an illustration of the entire toner pack  620  according to this embodiment.  FIG.  143    is an exploded perspective view of a restriction releasing mechanism  604 , and is a view as seen from the second end side (nozzle side) in the first direction D 1 .  FIG.  144    is a detailed illustration of a shape and an assembly method of the restriction releasing mechanism  604  (projecting portion). Part (a) of  FIG.  144    shows a method of assembling the second restriction releasing member  604 B to the first restriction releasing member  604 A, and part (b) of  FIG.  144    shows the assembly method of the fixing pin  630  to the first restriction releasing member  604 A and the second restriction releasing member  604 B. 
     As shown in  FIG.  142   , in the toner pack  620  of this embodiment, in addition to the toner accommodating portion  201 , the nozzle  302 , and the pack side shutter  203 , a restriction releasing mechanism  604  partially projecting in the arrow N direction (downward) from the end surface  203   c  of the pack side shutter  203  is provided. 
     Next, referring to  FIGS.  143  and  144   , the restriction releasing mechanism  604  will be described. 
     As shown in  FIG.  143   , the restriction releasing mechanism  604  comprises a first restriction releasing member  604 A, a second restriction releasing member  604 B, and a fixing pin  630 . 
     The first restriction releasing member  604 A has a generally cylindrical shape including a cylindrical portion  604 Ac centered on the rotational axis A (central axis). At the end of the cylindrical portion  604 Ac in the arrow U direction (upward direction), a substantially disk-shaped end portion  604 Af projecting in the radial direction r of the imaginary circle VC centered on the rotational axis A is provided. A pair of projections  604 Ae projecting in the arrow N direction (downward) is provided at the end in the imaginary circle VC centered on the rotational axis A of the end portion  604 Af in the radial direction r. The projection  604 Ae has a shape which is 180-degree rotationally symmetric with respect to the rotational axis A. In addition, a proper gap  604 Ai is provided between the cylindrical portion  604 Ac and the projection  604 Ae in the radial direction r of the imaginary circle VC centered on the rotational axis A so that the second restriction releasing member  604 B which will be described hereinafter can be assembled up to the end portion  604 Af (see  FIG.  145   ). Further, as shown in part (a) of  FIG.  144   , the end portion  604 Af is provided with a hole portion  604 Ah centered on the rotational axis A. The cylindrical portion  604 Ac is provided with a pair of oblong holes  604 Ad formed along the rotational direction K, and the pair of oblong holes  604 Ad have symmetric shapes with respect to the rotational axis A. The semicircular round holes at both ends in the longitudinal direction of the oblong hole  604 Ad each includes, a round hole portion  604 Ad 1  in the upstream side in the rotational direction K, a round hole portion  604 Ad 3  in the downstream side in the rotational direction K, and an oblong hole portion  604 Ad 2  connecting between the round hole portion  604 Ad 1  and the round hole portion  604 Ad 3 . A straight line connecting the center of one round hole portion  604 Ad 1  and the center of the other round hole portion  604 Ad 1  and a straight line connecting the center of one round hole portion  604 Ad 3  and the other round hole portion  604 Ad 3  pass the rotational axis A orthogonally. Further, the diameters of the round holes  604 Ad 1  and  604 Ad 3  are selected to be slightly larger than the diameter of the fixing pin  630 . Further, the width of the oblong hole portion  604 Ad 2  in the rotational axis A direction is selected to be slightly smaller than the diameter of the fixing pin  630 . The reason for this will be described when the operation of the restriction releasing mechanism  604  is explained. Referring the end portion of the cylindrical portion  604 Ac on the arrow N direction (downward) side as the end portion  604 Ag, a first restriction releasing portion  604 Aa and a first restriction releasing portion  604 Ab constituting a pair and projecting from the end portion  604 Ag in the arrow N direction (downward). The first restriction releasing portion  604 Aa and  604 Ab have shapes which is 180-degree rotationally symmetric with respect to the rotational axis A. Further, of the first restriction releasing portion  604 Aa and the first restriction releasing portion  604 Ab constituting the pair, the one closer to the opening  302   a  of the nozzle  302  is the first restriction releasing portion  604 Aa, in a state where the restriction releasing mechanism  604  which will be described hereinafter is assembled to the nozzle  302 . The first restriction releasing portion  604 Aa comprises a first slope  604 Aa 1  (first inner engaging surface, first downward surface, first downward guide surface, first force applying surface, first push surface) and a first abutment surface  604 Aa 2 . The first slope  604 Aa 1  and the first abutment surface  604 Aa 2  have the same shapes as the first slope  304   a   1  and the first abutment surface  304   a   5  of the first restriction releasing portion  304   a  of Embodiment 3 (see  FIG.  106   ), respectively, and therefore, the description thereof will be omitted. Further, the first restriction releasing portion  604 Ab has a shape which is 180 degree rotationally symmetric with the first restriction releasing portion  604 Aa with respect to the rotational axis A as described above, and therefore, the description of the detailed shape is omitted. The first restriction releasing portion  604 Ab does not necessarily have to be 180-degree rotationally symmetric with the first restriction releasing portion  604 Aa with respect to the rotational axis A. The first restriction releasing portion  604 Ab is preferably rotationally symmetric with the first restriction releasing portion  604 Aa at 150 degrees or more and 210 degrees or less with respect to the rotational axis A. 
     The second restriction releasing member  604 B has a generally cylindrical shape including a cylindrical portion  604 Bc centered on the rotational axis A. An inner diameter portion of the cylindrical portion  604 Bc thereof is an inner peripheral surface  604 Bg, an end of the cylindrical portion  604 Bc on the arrow N direction (lower) side is an end portion  604 Bf, an end on the arrow U direction (upper) side is an end portion  604 Be. The cylindrical portion  604 Bc is provided with a pair of hole portions  604 Bd which are 180-degree rotationally symmetric with respect to the rotational axis A. A straight line connecting the centers of the pair of hole portions  604 Bd passes through the rotational axis A substantially orthogonally. The cylindrical portion  604 Bc is provided with a pair of second restriction releasing portions  604 Ba and  604 Bb projecting from the end portion  604 Bf in the direction (downward) of the arrow N. The pair of second restriction releasing portion  604 Ba and second restriction releasing portion  604 Bb have shapes of 180 degree rotational symmetry about the rotational axis A. In addition, of the second restriction releasing portion  604 Ba and the second restriction releasing portion  604 Bb, the one closer to the opening  302   a  of the nozzle  302  is the second restriction releasing portion  604 Ba, in a state that the restriction releasing mechanism  604  which will be described hereinafter is assembled to the nozzle  302 . The second restriction releasing portion  604 Ba comprises a second slope  604 Ba 1  (first outer engagement surface, second downward surface, second downward guide surface, second force application surface, second push surface), a flat surface  604 Ba 2  (second engagement surface, an upward surface, an upward engaging surface, an upward push surface, an upward force applying surface), and a second abutment surface  604 Ba 3  (contacted surface). The second slope  604 Ba 1 , the flat surface  604 Ba 2 , and the second abutment surface  604 Ba 3  have the same shapes as the second slope  304   a   2 , the flat surface  304   a   3 , and the second abutment surface  304   a   6  in Embodiment 3 (see  FIG.  106   ), and therefore, the detailed description will be omitted. In addition, the second restriction releasing portion  604 Bb has a shape which is 180-degree rotationally symmetric with the second restriction releasing portion  604 Ba with respect to the rotational axis A as described above, and therefore, the description of the detailed shape is omitted. The second restriction releasing portion  604 Bb does not necessarily have to be 180-degree rotationally symmetric with the second restriction releasing portion  604 Ba with respect to the rotational axis A. The second restriction releasing portion  604 Bb is preferably 150 degrees or more and 210 degrees or less rotationally symmetric with the second restriction releasing portion  604 Ba with respect to the rotational axis A. 
     As shown in  FIG.  143   , the fixing pin  630  has an elongated substantially cylindrical shape centered on the axis B 60 . 
     (Assembling of Toner Pack) 
     Referring to  FIGS.  144  and  145   , the assembling of the toner pack  620  according to this embodiment will be described.  FIG.  145    is a sectional view of the toner pack  620  after the assembling, taken along a line X 601 -X 601  shown in  FIG.  142    and along the pin  310  with the rotational axis A as the center. 
     The assembly other than the restriction releasing mechanism  604  is the same as in Embodiments 2 and 3, and therefore, the description thereof will be omitted. 
     First, as shown in part (a) of  FIG.  144   , the second restriction releasing member  604 B is telescoped on the first restriction releasing member  604 A in the arrow U direction (upward) so that the inner peripheral surface  604 Bg is relatively inserted into the cylindrical portion  604 Ac. The inner peripheral surface  604 Bg of the second restriction releasing member  604 B and the cylindrical portion  604 Ac of the first restriction releasing member  604 A are supported slidably relative to each other. As described above, since the gap  604 Ai (see  FIG.  145   ) is provided between the projection  604 Ae of the first restriction releasing member  604 A and the cylindrical portion  604 Ac, the end portion  604 Be of the second restriction releasing member  604 B can be inserted until it comes into contact with the end portion  604 Af of the first restriction releasing member  604 A. 
     Next, referring to part (b) of  FIG.  144   , the assembly of the fixing pin  630  to the first restriction releasing member  604 A and to the second restriction releasing member  604 B will be described. Prior to the assembling of the fixing pin  630 , the center of the hole portion  604 Bd of the second restriction releasing member  604 B and the center of the round hole portion  604 Ad 1  of the oblong hole  604 Ad of the first restriction releasing member  604 A are aligned with each other. From this state, the fixing pin  630  is inserted in the direction of an arrow V 60  through one of the hole portions  604 Bd of the second restriction releasing member  604 B, one of the round holes  604 Ad 1  of the first restriction releasing member  604 A, the other round hole  604 Ad 1 , and the other hole portion  604 Bd of the second restriction releasing member  604 B, in this order. The fixing pin  630  is fixed to the hole portion  604 Bd of the second restriction releasing member  604 B by means such as adhesion, clamping, or press fitting. By this, the assembly of the restriction releasing mechanism  604  is completed. 
     Next, referring to  FIG.  145   , the assembly of the restriction releasing mechanism  604  on the nozzle  302  will be described. The restriction releasing mechanism  604  is assembled to the nozzle  302  in the direction of the arrow U (upward), and the cylindrical portion  604 Ac is supported by the cylindrical support portion  302   b . In addition, a pair of projections  604 Ae of the first restriction releasing member  604 A are inserted into a pair of cut-away portions  302   c  of the nozzle  302 . By the engagement between the projection  604 Ae of the first restriction releasing member  604 A and the cut-away portion  302   c , the movement of the first restriction releasing member  604 A relative to the nozzle  302  around the rotational axis A is restricted. Therefore, the first restriction releasing member  604 A is movably supported only in the direction of the rotational axis A relative to the nozzle  302 . Further, when the first restriction releasing member  604 A is inserted into the nozzle  302  in the direction of the arrow U (upward), the small diameter shaft portion  331   c  of the shaft member  331  is inserted into the hole portion  604 Ah of the first restriction releasing member  604 A, and the end portion  604 Af abuts on the shaft ring  334 . 
     Similarly to Embodiment 3, the shaft ring  335  is telescoped over the small diameter shaft portion  331   c  to a position where the hole  335   a  abuts against the end portion  604 Aj of the first restriction releasing member  604 A, and is fixed to the small diameter shaft portion  331   c  of the shaft member  331 . Through the above-described process, the assembly of the restriction releasing mechanism  604  to the nozzle  302  is completed. 
     (Operation of Restriction Releasing Mechanism) 
     Next, referring to  FIGS.  146  and  147   , the operation of the restriction releasing mechanism will be described.  FIG.  146    is an illustration of the operation of the restriction releasing mechanism  604  in this embodiment. Part (a) of  FIG.  146    shows a first position (aligned position) in which the second restriction releasing member  604 B is such that the first slope  604 Aa 1  of the first restriction releasing member  604 A and the second slope  604 Ba 1  of the second restriction releasing member  604 B are aligned with each other. Part (b) of  FIG.  146    shows a state in which the second restriction releasing member  604 B is in the second position (non-aligned position) which is the position rotated in the rotational direction K from the first position.  FIG.  147    is a detailed view of the toner pack  620  as viewed from the side (nozzle side) of the second end portion in the first direction D 1 , and part (a) thereof shows a state in which the second restriction releasing member  604 B is in the first position, and part (b) shows a state in which the second restriction releasing member  604 B is in the second position. 
     First, as shown in part (a) of  FIG.  146   , when the second restriction releasing member  604 B is in the first position, the center of the hole portion  604 Bd of the second restriction is coincident with the center of the center of the round hole portion  604 Ad 1  of the oblong hole  604 Ad of the first restriction releasing member  604 A, by way of the fixing pin  630 . In this state, as shown in part (a) of  FIG.  147   , the first restriction releasing portion  604 Aa and the second restriction releasing portion  604 Ba is such that the first slope  604 Aa 1  and the second slope  604 Ba 1  are aligned with each other both in the rotational direction K about the rotational axis A and in the direction of the rotational axis A. That is, the first slope  604 Aa 1  and the second slope  604 Ba 1  are at the same position in the circumferential direction of the imaginary circle VC. 
     In order to move the second restriction releasing member  604 B to the second position from this state (first position), the user rotates the second restriction releasing member  604 B relative to the first restriction releasing member  604 A in the rotational direction K about the rotational axis A. In interrelation with this, the fixing pin  630  (see  FIG.  146   ) are fixed by the hole portion  604 Bd of the second restriction releasing member  604 B at both ends thereof rotates in the rotational direction K about the rotational axis A. The fixing pin  630  passes from the round hole portion  604 Ad 1  upstream side (in the rotational direction K) of the oblong hole  604 Ad of the first restriction releasing member  604 A, through the oblong hole portion  604 Ad 2 , to the downstream side round hole portion  604 Ad 3  in the rotational direction K. By this, the second restriction releasing member  604 B rotates in the rotational direction K by the amount of rotation of the fixing pin  630 , and moves to the second position as shown in part (b) of  FIG.  146   . At this time, the center of the hole portion  604 Bd of the second restriction releasing member  604 B is coincident with the center of the round hole portion  604 Ad 3  of the oblong hole  604 Ad of the first restriction releasing member  604 A by way of the fixing pin  630 . That is, the first slope  604 Aa 1  and the second slope  604 Ba 1  are at different positions in the circumferential direction of the imaginary circle VC. 
     Here, in the direction of the rotational axis A, a width of the oblong hole portion  604 Ad 2  of the oblong hole  604 Ad is slightly smaller than the diameter of the fixing pin  630 . In addition, the diameters of the round holes  604 Ad 1  and  604 Ad 3  are slightly larger than the diameter of the fixing pin  630 . By this, when the fixing pin  630  is placed at the round hole portions  604 Ad 1  and  604 Ad 3 , it cannot move to the oblong hole portion  604 Ad 2  unless a certain force is applied. Therefore, when the second restriction releasing member  604 B is in the first position or the second position, the position is prevented from changing at an unintended timing, and therefore, the user can apply the force to change the position at a user&#39;s own timing. Further, when the fixing pin  630  moves, the resistance is different between the long hole portion  604 Ad 2  of the oblong hole  604 Ad and the round hole portions  604 Ad 1  and  604 Ad 3 , so that the applied force changes. When the user&#39;s hand operating (rotating) the second restriction releasing member  604 B feels this change in force, the user can recognizes that the operation of the second restriction releasing member  604 B is completed. 
     When the second restriction releasing member  604 B is located at the second position, as shown in part (b) of  FIG.  147   , the first restriction releasing portion  604 Aa and the second restriction releasing portion  604 Ba are such that the first slope  604 Aa 1  and the second slope  604 Ba 1  are at different positions in the rotational direction about the rotational axis A and in the direction of the rotational axis A. The positional relationship at this time between the first restriction releasing portion  604 Aa and the second restriction releasing portion  604 Ba is set to be the same as that of the first restriction releasing portion  304   a  of Embodiment 3 (see  FIG.  106   ). 
     In order to move the second restriction releasing member  604 B from the second position to the first position in this state, the second restriction releasing member  604 B is rotated in the direction of arrow L about the rotational axis A relative to the first restriction releasing member  604 A. By this, the second restriction releasing member  604 B moves from the second position to the first position through reverse process of the movement from the first position to the second position. 
     (Mounting and Dismounting of Toner Pack) 
     Next, mounting and dismounting of the toner pack  620  to and from the mounting portion  206  will be described. When mounting the toner pack  620  on the mounting portion  206 , the second restriction releasing member  604 B shown in part (b) of  FIG.  147    is moved to the second position in advance before mounting. As described above, when the second restriction releasing member  604 B is in the second position, the relationship between the first restriction releasing portion  604 Aa of the first restriction releasing member  604 A and the second restriction releasing portion  604 Ba of the second restriction releasing member  604 B is the same as that of the first restriction releasing portion  304   a  of Embodiment 3. Therefore, the mounting and dismounting operations of the toner pack  620  to and from the mounting portion  206  is the same as the operations of mounting and dismounting of the toner pack  320  to and from the mounting portion  206  of Embodiment 3. Therefore, the description thereof will be omitted. 
     Embodiment 7 
     Next, referring to  FIGS.  148  to  161   , Embodiment 7 will be described in the following. In this embodiment, the structure of the restriction releasing member is different from that in Embodiment 3. The same points as in the above-described embodiment will be omitted. In particular, of the elements disclosed in this embodiment, those corresponding to the members described in Embodiments 2 and 3 are assigned the same names as the members of Embodiments 2 and 3, and only the points different from Embodiments 2 and 3 will be described. 
     (Toner Pack Structure) 
     Referring to  FIGS.  148  to  151   , the toner pack  720  in this embodiment will be described.  FIG.  148    is an illustration of the entire toner pack  720  in this embodiment.  FIG.  149    is an exploded perspective view of a restriction releasing mechanism  704 . Part (a) of  FIG.  149    is a view as seen from a second end side (nozzle side) in a first direction D 1 , and part (b) of  FIG.  149    is a view as seen from a first end side (accommodation portion side) in the first direction D 1 .  FIG.  150    is a detailed view of a first restriction releasing member  704 A and a second restriction releasing member  704 B. Part (a) of  FIG.  150    shows the first restriction releasing member  704 A, and part (b) of  FIG.  150    shows the second restriction releasing member  704 B.  FIG.  151    is a sectional view of the toner pack  720  after assembly, taken along a line X 701 -X 701  shown in  FIG.  148    and along a pin  310  with the rotational axis A as the center. 
     As shown in  FIG.  148   , in the toner pack  720  of this embodiment includes a restriction releasing mechanism  704  (projection portion) which partially projects in the direction (downward) of the arrow N from the end surface  203   c  of the pack-side shutter  203 , in addition to the accommodating portion  201  for accommodating the toner, the nozzle  302 , and the pack-side shutter  203 . 
     Next, referring to  FIG.  149   , the restriction releasing mechanism  704  will be described. The restriction releasing mechanism  704  comprises a first restriction releasing member  704 A (first projection member), a second restriction releasing member  704 B (second projection member), an initialization spring  730 , and an advancing/retracting member  731  (moving member). 
     The first restriction releasing member  704 A has a generally cylindrical shape including a cylindrical portion  704 Af centered on the rotational axis A (central axis). The end portion of the cylindrical portion  704 Af on the arrow N direction (lower) side is referred to as an end portion  704 Ag, and the inner peripheral surface of the cylindrical portion  704 Af is referred to as an inner peripheral surface  704 Ae (first inner peripheral surface). The inner peripheral surface  704 Ae is a surface extending in the direction of the rotational axis A with the rotational axis A as the center. The cylindrical portion  704 Af is provided with a pair of first restriction releasing portions  704 Aa and  704 Ab projecting from the end portion  704 Ag in the direction of the arrow N (downward). Further, the cylindrical portion  704 Af is provided with a pair of cut-away portions  704 Ac and  704 Ad (first guide groove, first slit). The first restriction releasing portion  704 Ab and the cut-away portion  704 Ad have 180-degree symmetric shapes of the first restriction releasing portion  704 Aa and the cut-away portion  704 Ac, respectively with respect to the rotational axis A. In addition, in a state in which the restriction releasing mechanism  704  which will be described hereinafter is assembled to the nozzle  302 , the one of the first restriction releasing portion  704 Aa and  704 Ab that is closer to the opening  302   a  of the nozzle  302  in the circumferential direction of the imaginary circle VC is the first restriction releasing portion  704 Aa. Similarly, of the cut-away portions  704 Ac and  704 Ad constituting the pair, the one closer to the opening  302   a  of the nozzle  302  in the circumferential direction of the imaginary circle VC is referred to as the cut-away portion  704 Ac. Next, referring to part (a) of  FIG.  150   , the detailed shapes of the first restriction releasing portion  704 Aa and the cut-away portion  704 Ac will be described. A first restriction releasing surface  704 Aa 1  (downstream end surface) substantially parallel to the rotational axis A is provided on the end surface, on the downstream side in the rotational direction K, of the first restriction releasing portion  704 Aa. That is, the first restriction release surface  704   a   1  (first inner engaging surface, first force applying surface, first push surface) extends in the direction of the rotational axis A and faces downstream in the rotational direction K (first rotational direction). The cut-away portion  704 Ac is formed by an entrance portion  704 Ac 1 , an inclined portion  704 Ac 2 , and a straight portion  704 Ac 3 . The entrance portion  704 Ac 1  is a cut-away portion formed in the direction of the arrow U (upward), and is provided on the end portion  704 Ag on the downstream side in the rotational direction K from the first restriction releasing surface  704 Aa 1 . The inclined portion  704 Ac 2  is a cut-away portion formed, on the upstream side in the rotational direction K, in the direction of the arrow U (upward), and is provided connected with the entrance portion  704 Ac 1 . The straight portion  704 Ac 3  is a cut-away portion formed substantially parallel to the rotational axis A in the direction of the arrow U (upward), and is provided connected with the inclined portion  704 Ac 2 . A width of the cut-away portion  704 Ac is slightly larger than the diameter of the pin  731   b  of the advancing/retracting member  731 , which will be described hereinafter, and the pin  731   b  is selected to be able to path therethrough. The first restriction releasing portion  704 Ab and the cut-away portion  704 Ad have 180-degree symmetric shapes of the first restriction releasing portion  704 Aa and the cut-away portion  704 Ac as described above with respect to the rotational axis A, and therefore, the description thereof is omitted. In this embodiment, the cut-away portion  704 Ac is provided so that the entrance portion  704 Ac 1  is on the downstream side of the first restriction releasing surface  704 Aa 1  in the rotational direction K, but this structure is not limiting to the present invention. The cut-away portion  704 Ac may be provided at any position in the rotational direction K as long as it does not hinder the formation of the first restriction releasing portion  704 Aa and the second restriction releasing portion  704 Ba of the second restriction releasing member  704 B which will be described hereinafter. 
     As shown in  FIG.  149   , the second restriction releasing member  704 B has a generally cylindrical shape including a cylindrical portion  704 Bc centered on the rotational axis A. An end of the cylindrical portion  704 Bc on the (lower) side in the arrow N is referred to as an end portion  704 Bh, and an inner peripheral surface of the cylindrical portion  704 Bc is referred to as an inner peripheral surface  704 Be (second inner peripheral surface). The inner peripheral surface  704 Be is a surface extending in the direction of the rotational axis A with the rotational axis A as the center. An end portion  704 Bf is on the arrow U direction (upper side) side of the cylindrical portion  704 Bc. The end portion  704 Bf is provided with a hole portion  704 Bg centered on the rotational axis A. The cylindrical portion  704 Bc is provided with a pair of projections  704 Bd projecting in the radial direction r of the imaginary circle VC centered on the rotational axis A. In addition, the pair of projections  704 Bd are provided so as to have shapes 180-degree symmetric with respect to the rotational axis A. The cylindrical portion  704 Bc is provided with a pair of second restriction releasing portions  704 Ba (first projections) and second restriction releasing portions  704 Bb (second projections) projecting from the end portion  704 Bh in the direction of the arrow N (downward). Further, the cylindrical portion  704 Bc is provided with a pair of cut-away portions  704 Bi (see  FIG.  150   ) and  704 Bj (second guide groove, second slit). The second restriction releasing portion  704 Bb and the cut-away portion  704 Bj have shapes 180 degree symmetric about the rotational axis A with respect to the second restriction releasing portion  704 Ba and the cut-away portion  704 Bi, respectively. Further, in a state where the restriction releasing mechanism  704  which will be described hereinafter is assembled to the nozzle  302 , of the second restriction releasing portions  704 Ba and  704 Bb constituting the pair, the second restriction releasing portion  704 Ba is closer to the opening  302   a  of the nozzle  302  in the circumferential direction of the imaginary circle VC. Similarly, of the pair of cut-away portions  704 Bi and  704 Bj, the cut-away portion  704 Bi is closer to the opening  302   a  of the nozzle  302  in the circumferential direction of the imaginary circle VC. 
     Next, referring to part (b) of  FIG.  150   , the detailed shapes of the second restriction releasing portion  704 Ba and the cut-away portion  704 Bi will be described. The second restriction releasing portion  704 Ba comprises a second slope  704 Ba 1 , a flat surface  704 Ba 2 , and an abutment surface  704 Ba 3 . The second slope  704 Ba 1  (second outer engaging surface, second downward guide surface, second downward surface), flat surface  704 Ba 2  (second engaging surface, upward surface, upward engaging surface, upward push surface), abutment surface  704 Ba 3  (contacted surface) have the shapes similar to those of the second slope  304   a   2 , the flat surface  304   a   3 , and the second abutment surface  304   a   6  (see  FIG.  106   ), respectively in Embodiment 3, and therefore, the detailed description thereof will be omitted. The cut-away portion  704 Bi is formed substantially parallel to the rotational axis A in the direction of the arrow U (upward), and is provided on the end portion  704 Bh on the downstream side, in the rotational direction K, of the second restriction releasing portion  704 Ba. The cut-away portion part  704 Bi has a function of determining the phase in the rotational direction K with the first restriction releasing portion  704 Aa which will be described hereinafter, and therefore, it is determined by the position of the cut-away portion  704 Ac of the first restriction releasing portion  704 Aa. In addition, the surface of the end portion  704 Bf of second restriction releasing member  704 B on the arrow N direction (lower side) side is provided with a support cylinder  704 Bk centered on the rotational axis A (see  FIG.  151   ). 
     As shown in  FIG.  149   , the initialization spring  730  is a compression coil spring having a central axis aligned with the rotational axis A. 
     The advancing/retracting member  731  is a generally disk-shaped member including a disk portion  731   c  centered on the rotational axis A and a pair of pins  731   b . An end surface of the disk portion  731   c  in the arrow N direction (downward) is provided as a pushed surface  731   a . The pair of pins  731   b  are provided so as to project from the outer peripheral surface of the disk portion  731   c  in the radial direction r of the imaginary circle VC centered on the rotational axis A. The pair of pins  731   b  are arranged 180 degrees symmetrically with respect to the rotational axis A. A support cylinder  731   d  is provided at an end of the disk portion  731   c  in the arrow U direction (upward direction). 
     (Assembly of Toner Pack) 
     Referring to  FIGS.  149  and  151   , the assembling of the toner pack  720  according to this embodiment will be described. The assembling except for the restriction releasing mechanism  704  is similar to that of Embodiments 2 and 3, and therefore, the description thereof will be omitted. 
     As shown in part (a) of  FIG.  149   , for the assembling of the restriction releasing mechanism  704 , the second restriction releasing member  704 B, the shaft ring  335 , the first restriction releasing member  704 A, the initialization spring  730 , and the advancing/retracting member  731  are assembled to the nozzle  302  assembled up to the shaft ring  334 , in this order in the direction of arrow U (upward). The assembly order of the first restriction releasing member  704 A and the initialization spring  730  may be interchanged. 
     As shown in  FIG.  151   , the second restriction releasing member  704 B is telescoped on the small diameter shaft portion  331   c  of the shaft member  331  at the, the hole portion  704 Bg until it abuts to the shaft ring  334 , and the hole portion  704 Bg and the small diameter shaft portion  331   c  are slidable relative to each other. In addition, for the second restriction releasing member  704 B, the cylindrical portion  704 Bc is telescoped on the cylindrical support portion  302   b , and the projection  704 Bd is inserted into the cut-away portion  302   c  of the nozzle  302  (see  FIG.  149   ). By the engagement between the projection  704 Bd of the second restriction releasing member  704 B and the cut-away portion  302   c  of the nozzle  302 , the movement of the second restriction releasing member  704 B relative to the nozzle  302  around the rotational axis A is restricted. Therefore, the second restriction releasing member  704 B is supported movably only in the direction of the rotational axis A relative to the nozzle  302 . 
     The shaft ring  335  is telescoped on the small diameter shaft portion  331   c  at the hole  335   a  until it abuts to the end portion  704 Bf of the second restriction releasing member  704 B with respect to the small diameter shaft portion  331   c , and is fixed to the small diameter shaft portion  331   c.    
     The first restriction releasing member  704 A is inserted into the second restriction releasing member  704 B so that the cylindrical portion  704 Af is rotationally supported by the inner peripheral surface  704 Be. In other words, the first restriction releasing member  704 A is provided rotatably about the rotational axis A inside the inner peripheral surface  704 Be of the second restriction releasing member  704 B in the radial direction r. In addition, the first restriction releasing member  704 A is inserted until it abuts to the end portion  704 Bf of the second restriction releasing member  704 B. And, a retaining portion (not shown) is provided on the inner peripheral surface  704 Be of the second restriction releasing member  704 B so as to project inward in the radial direction r of the imaginary circle VC centered on the rotational axis A. By engagement between the retaining portion and the first restriction releasing member  704 A, the movement of the first restriction releasing member  704 A in the rotational axis A direction is restricted. Therefore, the first restriction releasing member  704 A is supported so as to be movable (rotatable) only about the rotational axis A relative to the second restriction releasing member  704 B. 
     The initialization spring  730  is fixed to the support cylinder  704 Bk of the second restriction releasing member  704 B by press fitting or the like. 
     The advancing/retracting member  731  is inserted into the first restriction releasing member  704 A so that the disk portion  731   c  is slidably supported by the inner peripheral surface  704 Ae. In other words, the advancing/retracting member  731  is provided so as to be movable in the direction of the rotational axis A inside the inner peripheral surface  704 Ae of the first restriction releasing member  704 A in the radial direction r. At this time, the pin  731   b  of the advancing/retracting member  731  shown in  FIG.  149    is inserted into the entrance portions  704 Ac 1 ,  704 Ad 1  of the cut-away portions  704 Ac,  704 Ad of the first restriction releasing member  704 A and into the cut-away portions  704 Bi,  704 Bj of the second restriction releasing member  704 B (Figure See  150 ). By this, the position of the first restriction releasing member  704 A relative to the second restriction releasing member  704 B is restricted in the rotational direction K by the pin  731   b  of the advancing/retracting member  731 . In addition, by engaging the pin  731   b  with the cut-away portion  704 Bi, the advancing/retracting member  731  is restricted in the rotation around the rotational axis A relative to the second restriction releasing member  704 B. Therefore, the advancing/retracting member  731  is supported movably only in the direction of the rotational axis A relative to the second restriction releasing member  704 B. 
     Finally, the advancing/retracting member  731  is fixed by fixing the support cylinder  731   d  to the end portion of the initialization spring  730  by press fitting, adhesion or the like. The restriction releasing mechanism  704  is assembled by the above process. The initialization spring  730  urges the advancing/retracting member  731  in the direction away from the accommodating portion  201  in the direction of the rotational axis A. 
     (Operation of Restriction Releasing Mechanism) 
     Next, referring to  FIG.  152   , the operation of the restriction releasing mechanism  704  will be described.  FIG.  152    is a perspective view illustrating the operation of the restriction releasing mechanism  704 . Part (a) of  FIG.  152    shows a state in which the advancing/retracting member  731  has moved in the direction of arrow N (downward) relative to the first restriction releasing member  704 A, and the pin  731   b  is in the entrance portion  704 Ac 1 . Part (b) of  FIG.  152    shows a state in which the pin  731   b  of the advancing/retracting member  731  is in contact with the inclined portion  704 Ac 2  of the first restriction releasing member  704 A. Part (c) of  FIG.  152    shows a state in which the advancing/retracting member  731  has moved in the direction of the arrow U (upward) relative to the first restriction releasing member  704 A, and the pin  731   b  is in the straight portion  704 Ac 3 . 
     As shown in part (a) of  FIG.  152   , when the advancing/retracting member  731  is placed in arrow N direction side of (below) the first restriction releasing member  704 A, the pin  731   b  of the advancing/retracting member  731  is placed in the entrance portion  704 Ac 1  of the first restriction releasing member  704 A. When a force F 700  in the arrow U direction (upward) is applied to the pushed surface  731   a  of the advancing/retracting member  731 , the advancing/retracting member  731  is moved in the arrow U direction (upward) against the spring force of the initialization spring  730  (see  FIG.  151   ) due to the force F 700 . The arrow U direction is the direction in which the advancing/retracting member  731  approaches the accommodating portion  201 . At this time, since the pin  731   b  is restricted in the movement in the rotational direction K by the cut-away portion  704 Bi of the second restriction releasing member  704 B, the advancing/retracting member  731  moves only in the arrow U direction (upward). 
     When the advancing/retracting member  731  receives the force F 700  in the arrow U direction (upward) and continues to move further in the arrow U direction (upward), the pin  731   b  abuts on the inclined portion  704 Ac 2  of the first restriction releasing member  704 A, and the resultant state is shown in part (b) of  FIG.  152   . As described above, the inclined portion  704 Ac 2  is inclined toward the upstream side in the rotational direction K and the arrow U direction (upward). Therefore, the first restriction releasing member  704 A receives a force F 701  including a component downstream in the rotational direction K from the pin  731   b . Since the movement of the first restriction releasing member  704 A in the rotational axis A direction is restricted, the first restriction releasing member  704 A is rotated in the rotational direction K (first rotational direction) by the force F 701 . That is, the first restriction releasing member  704 A rotates in the rotational direction K relative to the second restriction releasing member  704 B. In Interrelation with this, the first restriction releasing portion  704 Aa of the first restriction releasing member  704 A also rotates in the rotational direction K. That is, as the advancing/retracting member  731  moves in the direction of the arrow U (upward), the first restriction releasing portion  704 Aa of the first restriction releasing member  704 A rotates in the rotational direction K relative to the second restriction releasing member  704 B. That is, the advancing/retracting member  731  is structured to rotate the first restriction releasing member  704 A and the second restriction releasing member  704 B in the rotational direction K by being moved in the arrow U direction (upward). 
     When the advancing/retracting member  731  receives the force F 700  in the arrow U direction (upward) and is moved in the arrow U direction (upward), the first restriction releasing member  704 A further rotates in the rotational direction K, and the phases of the pin  731   b  the and the straight portion  704 Ac 3  match are aligned. And, the pin  731   b  of the advancing/retracting member  731  becomes in a state of being inserted up to the straight portion  704 Ac 3  as shown in part (c) of  FIG.  152   . When the pin  731   b  of the advancing/retracting member  731  is inserted up to the straight portion  704 Ac 3 , the first restriction releasing member  704 A becomes in a state where the movement of the first restriction releasing member  704 A relative to the second restriction releasing member  704 B in the rotational direction K is restricted by the pin  731   b.    
     When the force F 700  on the pushed surface  731   a  of the advancing/retracting member  731  is released, the advancing/retracting member  731  moves in the arrow N direction (downward) by the force F 702  from the initialization spring  730  (see  FIG.  151   ). Then, through the reverse process of the movement of the advancing/retracting member  731  in the arrow U direction (upward), the advancing/retracting member  731  shown in part (a) of  FIG.  152    becomes in the state of having been moved relative to the first restriction releasing member  704 A and the arrow N direction (downward). 
     The foregoing is the operation of the restriction releasing mechanism  704 . 
     (Mounting and Dismounting of Toner Pack) 
     Next, referring to  FIG.  153   , mounting/dismounting of the toner pack  720  to/from the mounting portion  206  will be described. As for the mounting operation of the toner pack  720 , only the operations different from those of Embodiments 2 and 3 will be described.  FIG.  153    is sectional views illustrating a process in which the restriction releasing mechanism  704  releases the rotation restricting mechanism  212  when the toner pack  720  is mounted to the mounting portion  206 . Some portions are not shown for the sake of better illustration. Further, the states of part (a) of  FIG.  153    to part ( e ) of  FIG.  153    will be described hereinafter. 
     Part (a) of  FIG.  153    shows a state in which the pushed surface  731   a  of the advancing/retracting member  731  is in contact with a free end portion  209   d   70  of the center boss  209   d  of the apparatus-side shutter  209 . In this state, the pin  731   b  of the advancing/retracting member  731  is located at the entrance portion  704 Ac 1  of the first restriction releasing member  704 A. At this time, the first restriction releasing surface  704 Aa 1  of the first restriction releasing member  704 A is placed on the upstream side, in the rotational direction D, of the contact surface  214   f  of the releasing claw  214   e . It is preferable that immediately before the pin  731   b  of the advancing/retracting member  731  enters the inclined portion  704 Ac 2  of the first restriction releasing member  704 A, the first restriction releasing surface  704 Aa 1  is partly overlapped with the contact surface  214   f  of the releasing claw  214   e  is in the rotational axis A direction. Further, the second slope  704 Ba 1  of the second restriction releasing member  704 B is placed on the downstream side of the second guided surface  214   e   2  of the releasing claw  214   e  in the rotational direction D. In the Figure, the neighborhood of the second slope  704 Ba 1  of the second restriction releasing member  704 B and the neighborhood of the contact surface  214   f  of the releasing claw  214   e  appear to overlap, but there is a gap in the direction perpendicular to the sheet of the drawing (direction perpendicular to the rotational axis A), and therefore, the toner pack  720  can move in the N direction (downward) of the arrow without interfering. 
     When the toner pack  720  is further moved in the N direction (downward) of the arrow from this position, the pushed surface  731   a  of the advancing/retracting member  731  receives a force F 703  from the free end portion  209   d   70  of the center boss  209   d . By this, the advancing/retracting member  731  moves in the direction of arrow G (upward) relative to the first restriction releasing member  704 A and the second restriction releasing member  704 B. As described above, by the movement of the advancing/retracting member  731  in the arrow G direction (upward), the first restriction releasing member  704 A is rotated in the rotational direction D (first rotational direction). By the rotation of the first restriction releasing member  704 A, the first restriction releasing surface  704 Aa 1  abuts to the contact surface  214   f  of the releasing member  214 , and a force F 704  is applied to the releasing member  214 . That is, the first restriction releasing surface  704 Aa 1  functions as a force applying surface. By the force F 704 , the releasing member  214  is rotated in the rotational direction D against the moment M 202  provided by the releasing spring  216  (see  FIG.  50   ). As the releasing member  214  rotates in the rotational direction D, the second guided surface  214   e   2  and the third guided surface  214   e   3  of the releasing claw  214   e  are exposed to the outside as shown in part (c) of  FIG.  66   . 
     When the toner pack  720  is further moved in the arrow N direction (downward) from this position, the rotation of the releasing member  214  in the rotational direction D provides the state in which the second slope  704 Ba 1  of the restriction releasing portion  704 Ba and the second guided surface  214   e   2  of the releasing claw  214   e  are overlapped as viewed in the direction of the rotational axis A, as shown in part (b) of  FIG.  153   . That is, when the toner pack  720  is further moved in the direction of the arrow N (downward), the second slope  704 Ba 1  of the second restriction releasing portion  704 Ba and the second guided surface  214   e   2  of the releasing claw  214   e  are brought into contact with each other. In addition, the pin  731   b  of the advancing/retracting member  731  at this time is inserted until it reaches the position of the straight portion  704 Ac 3  of the first restriction releasing member  704 A. That is, even if the advancing/retracting member  731  moves in the arrow G direction (upward) relative to the first restriction releasing member  704 A and the second restriction releasing member  704 B by the force F 703 , the first restriction releasing member  704 A does not rotate any more in the rotational direction D. 
     When the toner pack  720  is further moved in the direction (downward) of the arrow N from this position, the operation is the same as that of Embodiments 2 and 3, and therefore, detailed explanation is omitted, but the releasing member  214  is rotated in the rotational direction D by the contact between the second guided surface  214   e   2  and the second slope  704 Ba 1 . The releasing member  214  rotates in the rotational direction D until the second guided surface  214   e   2  passes the downstream end of the second slope  704 Ba 1  in the rotational direction D, and the state shown in part (c) of  FIG.  153    results. Even in this state, the pin  731   b  of the advancing/retracting member  731  is placed at the straight portion  704 Ac 3  of the first restriction releasing member  704 A. Then, when the toner pack  720  is further moved in the arrow N direction (downward) from this position, the advancing/retracting member  731  is moved in the arrow G direction (upward) relative to the first restriction releasing member  704 A and the second restriction releasing member  704 B by the force F 703 . Further, the third guided surface  204   e   3  of the releasing claw  214   e  passes in the flat surface  704 Ba 2  of the second restriction releasing portion  704 Ba in the direction of the arrow N. Since the similar operation is performed in Embodiment 3, detailed description thereof will be omitted, but the contact surface  214   a  of the releasing claw  214   e  abuts on the abutment surface  704 Ba 3  of the second restriction releasing portion  704 Ba as shown in part (d) of  FIG.  153   . Thereafter, since the operation is similar to that of Embodiment 3, detailed description thereof will be omitted, but by operating the operating member  330  (see  FIG.  149   ), the second restriction releasing member  704 B is moved in the direction of the arrow G to move the claw  214   e  in the direction of arrow G. By this, as shown in part ( e ) of  FIG.  153   , the restricting member  213  is moved in the direction of arrow G (upward) together with the releasing member  214 , and the rotation restriction by the rotation restricting mechanism  212  of the apparatus-side shutter  209  is released. With the foregoing, the toner pack  720  is in the mounted state. 
     The operation of dismounting the toner pack  720  from the mounting portion  206  is similar to that of Embodiment 3, the description thereof will be omitted. 
     In this embodiment, the flat surface  704 Ba 2  of the second restriction releasing portion  704 Ba is structured as a surface substantially perpendicular to the rotational axis A, but the structure similar to that of the third slope  204   a   3  (see  FIG.  65   ) of Embodiment 2 may be employed. 
     Modified Example 1 
     In this embodiment, the second slope  704 Ba 1  of the second restriction releasing portion  704 Ba faces in the direction of the arrow N (downward), and extends such as to go in the arrow U direction (upward) as goes in the rotational direction K (first rotational direction) about the rotational axis A. However, the present invention is not limited to such a structure. In this modified example, the second slope has a surface perpendicular to the rotational axis A. Referring to  FIGS.  154  and  155    this modified example will be described in the following. 
     Referring to  FIG.  154   , the first restriction releasing member  7104 A and the second restriction releasing member  7104 B in this modified example will be described.  FIG.  154    is a detailed view of the first restriction releasing member  7104 A and the second restriction releasing member  7104 B, in which part (a) thereof represents the first restriction releasing member  7104 A, and part (b) thereof represents the second restriction releasing member  7104 B. 
     As shown in part (a) of  FIG.  154   , the first restriction releasing member  7104 A is different from the first restriction releasing member  704 A (see part (a) of  FIG.  150   ) of this embodiment which is a base of this modified example, more particularly the shapes of pair of cut-away portion portions  7104 Ac and  7104 Ad (first guide groove, first slit) are different. The pair of cut-away portions  7104 Ac and  7104 Ad have symmetric shapes centered on the rotational axis A as in this embodiment, and therefore, only the cut-away portion  7104 Ac will be described, and the description of the cut-away portion  7104 Ad will be omitted. 
     The cut-away portion  7104 Ac is formed by an entrance portion  7104 Ac 1 , an inclined portion  7104 Ac 2 , a straight portion  7104 Ac 3 , and a step portion  7104 Ac 4 . 
     The entrance portion  7104 Ac 1  is a cut-away portion extended in the direction of the arrow U (upward), and is provided on an end portion  7104 Ag on a downstream side, in the rotational direction K, of a first restriction releasing surface  7104 Aa 1 . 
     The inclined portion  7104 Ac 2  is a cut-away portion formed toward the upstream side in the rotational direction K and in the direction of the arrow U (upward), and is provided in connection with the entrance portion  7104 Ac 1 . 
     The straight portion  7104 Ac 3  is a cut-away portion formed substantially parallel to the rotational axis A in the direction of the arrow U (upward), and is provided in connection with the inclined portion  704 Ac 2 . 
     The step portion  7104 Ac 4  is a cut-away portion formed toward the downstream side in the rotational direction K, and is provided in connection with the straight portion  7104 Ac 3 . 
     As shown in part (b) of  FIG.  154   , the second restriction releasing member  7104 B is different from the second restriction releasing member  704 B (see part (b) of  FIG.  150   ) of the present embodiment which is a base of this modified example, and more particularly the shapes of pair of second restriction releasing portions  7104 Ba and  7104 Bb are different. The pair of second restriction releasing portions  7104 Ba and  7104 Bb have symmetric shapes centered on the rotational axis A as in the embodiment, and therefore, the second restriction releasing portion  7104 Ba will be described, and the description of the second restriction releasing portion  7104 Bb will be omitted. 
     The second restriction releasing portion  7104 Ba comprises a downward surface  7104 Ba 1 , a flat surface  7104 Ba 2  (upward surface, upward engaging surface, upward push surface), and an abutment surface  7104 Ba 3 . The flat surface  7104 Ba 2  and the abutment surface  7104 Ba 3  of this modified example have the shapes similar to those of the flat surface  704 Ba 2  and the abutment surface  704 Ba 3  of the second restriction releasing member  704 B (see part (b) of  FIG.  150   ) of the embodiment. The downward surface  7104 Ba 1  is substantially perpendicular to the rotational axis A. The pair of cut-away portions  7104 Bi and  7104 Bj (second guide groove, second slit) of the second restriction releasing member  7104 B are the same as the pair of cut-away portions  704 Bi and  704 Bj, and therefore, the description thereof will be omitted. 
     Next, referring to  FIG.  155   , the mounting of the toner pack  7120  on the mounting portion  206  in this modified example will be described.  FIG.  155    is a sectional view illustrating a process of releasing the rotation restricting mechanism  212  when the toner pack  7120  is mounted to the mounting portion  206 . Some portions are not shown for the sake of better illustration. Further, the states shown in part (a) of  FIG.  153    to part ( e ) of  FIG.  153    will be described hereinafter as appropriate. 
     Part (a) of  FIG.  155    shows a state in which the toner pack  7120  is mounted on the mounting portion  206 , and the pushed surface  731   a  of the advancing/retracting member  731  is in contact with the free end portion  209   d   70  of the center boss  209   d  of the apparatus-side shutter  209 . In addition, in this state, the pin  731   b  of the advancing/retracting member  731  is at the entrance portion  7104 Ac 1  of the first restriction releasing member  7104 A. At this time, the first restriction releasing surface  7104 Aa 1  of the first restriction releasing member  7104 A is at a position upstream of the contact surface  214   f  of the releasing claw  214   e  in the rotational direction D. It is preferable that immediately before the pin  731   b  enters to the inclined portion  7104 Ac 2  of the first restriction releasing member  7104 A, the contact surface  214   f  of the first restriction releasing surface  7104 Aa 1  and the releasing claw  214   e  partially overlap in the rotational axis A direction. Further, the downward surface  7104 Ba 1  of the second restriction releasing member  7104 B is at a position on the downstream side, in the rotational direction D, of the second guided surface  214   e   2  of the releasing claw  214   e.    
     When the toner pack  7120  is further moved in the arrow N direction (downward) from this position, the releasing member  214  rotates in the rotational direction D by the same operation as in the embodiment which is the base of this modified example. Then, when the second guided surface  214   e   2  of the releasing claw  214   e  rotates until it passes the downstream end portion, in the rotational direction D, of the downward surface  7104 Ba 1  of the second restriction releasing member  7104 B, the state becomes as shown in part (b) of  FIG.  155   . In this state, the downward surface  7104 Ba 1  of the second restriction releasing member  7104 B is on the upstream side of the second guided surface  214   e   2  of the releasing claw  214   e  in the rotational direction D. Further, the first restriction releasing surface  7104 Aa 1  of the first restriction releasing member  7104 A is placed on the same side as or downstream side of the downward surface  7104 Ba 1  of the second restriction releasing member  7104 B in the rotational direction D. At this time, the pin  731   b  is placed on the straight portion  7104 Ac 3  of the first restriction releasing member  7104 A, and therefore, the rotation of the first restriction releasing member  7104 A about the rotational axis A relative to the second restriction releasing member  7104 B is restricted. 
     When the toner pack  7120  is further moved in the arrow N direction (downward) from this position, the flat surface  7104 Ba 2  of the second restriction releasing member  7104 B passes the third guided surface  214   e   3  of the releasing claw  214   e  in the arrow N direction (downward). In addition, at this time, the pin  731   b  passes the straight portion  7104 Ac 3  of the first restriction releasing member  7104 A in the direction of arrow G (upward) and moves to the step portion  7104 Ac 4 . Since the step portion  7104 Ac 4  is a cut-away portion toward the downstream side in the rotational direction D, the first restriction releasing member  7104 A becomes rotatable in the rotational direction E relative to the second restriction releasing member  7104 B. The first restriction releasing surface  7104 Aa 1  of the first restriction releasing member  7104 A is rotated in the rotational direction E by receiving the moment M 202  provided by the releasing spring  216  (see  FIG.  50   ) from the contact surface  214   f  of the releasing member  214 . The releasing claw  214   e  also rotates in the rotational direction E, and therefore, the contact surface  214   a  of the releasing claw  214   e  becomes in contact with the abutment surface  7104 Ba 3  of the second restriction releasing member  7104 B as shown in part (c) of  FIG.  155   . 
     Thereafter, the second restriction releasing member  7104 B is moved in the arrow G direction, and the releasing claw  214   e  is moved in the arrow G direction by the same method as in this embodiment. By this, as shown in part (d) of  FIG.  155   , the restricting member  213  is moved in the direction of arrow G (upward) together with the releasing member  214 , and the rotation restriction by the rotation restricting mechanism  212  of the apparatus-side shutter  209  is released. With the above-described operations, the mounting of the toner pack  7120  is completed. 
     The operation of removing the toner pack  7120  from the mounting portion  206  is the same as that of Embodiment 3, the description thereof will be omitted. 
     Modified Example 2 
     In, the restriction releasing mechanism  704  of this embodiment, the first restriction releasing member  704 A and the advancing/retracting member  731  are separate members. However, the first restriction releasing member  704 A and the advancing/retracting member  731  may be parts of one component. In such a case, the first restriction releasing member integrated with the advancing/retracting member is moved in the direction of the rotational axis A together with a rotation about the rotational axis A. Referring to  FIGS.  156  to  158   , such a structure will be described in the following as a next modified example. 
     Referring to  FIG.  156   , the restriction releasing mechanism  7204  in this modified example will be described.  FIG.  156    is an exploded perspective view of the restriction releasing mechanism  7204 . 
     The restriction releasing mechanism  7204  comprises a first restriction releasing member  7204 A, a second restriction releasing member  7204 B, and an initialization spring  730 . 
     The first restriction releasing member  7204 A has a substantially cylindrical shape including a cylindrical portion  7204 Af centered on the rotational axis A (central axis). The cylindrical portion  7204 Af is provided with a pair of pins  7204 Ah projecting in the radial direction r of the imaginary circle VC centered on the rotational axis A and provided symmetrically with respect to the rotational axis A. The surface of the cylindrical portion  7204 Af on the arrow N direction (downward) side is a pushed surface  7204 Ai, and there are provided first restriction releasing portions  7204 Aa and  7204 Ab projecting from the pushed surface  7204 Ai in the arrow N direction (downward). The first restriction releasing portion  7204 Aa and  7204 Ab have the same shapes as the first restriction releasing portion  704 Aa and  704 Ab, respectively of this embodiment which is a base of this modified example. 
     The second restriction releasing member  7204 B is different from the second restriction releasing member  704 B of this embodiment in the shapes of cut-away portions  7204 Bi (guide grooves) constituting the pair. The pair of cut-away portions  7204 Bi and  7204 Bj have symmetric shapes with respect to the rotational axis A similarly to the embodiment, the cut-away portion  7204 Bi will be described in this modified example, and the description of the cut-away portion  7204 Bj will be omitted. 
     The cut-away portion  7204 Bi comprises an entrance portion  7204 Bi 1 , an inclined portion  7204 Bi 2 , and a straight portion  7204 Bi 3 . The entrance portion  7204 Bi 1  is a cut-away portion formed in the direction of the arrow U (upward), and is provided on the end portion  7204 Bg on the downstream side, in the rotational direction K, of the abutment surface  7204 Ba 3  of the second restriction releasing portion  7204 Ba. The inclined portion  7204 Bi 2  is a cut-away portion formed on the downstream side in the rotational direction K and in the direction of the arrow U (upward), and is provided in connection with the entrance portion  7204 Bi 1 . The straight portion  7204 Bi 3  is a cut-away portion formed substantially parallel to the rotational axis A in the direction of the arrow U (upward), and is provided in connection with the inclined portion  7204 Bi 2 . 
     Next, the assembling of the restriction releasing mechanism  7204  in this modified example will be described. 
     The initialization spring  730  is assembled in the direction of arrow U to the second restriction releasing member  7204 B. At this time, the end portion of the initialization spring  730  is fixed to the cylindrical portion (see  FIG.  151   ) of the second restriction releasing member  7204 B, which is not shown, by adhesion or press fitting, as in the embodiment which is a base of this modified example. 
     The first restriction releasing member  7204 A is assembled to the second restriction releasing member  7204 B in the direction of arrow U. At this time, the cylindrical portion  7204 Af of the first restriction releasing member  7204 A is inserted to slide on the inner peripheral surface  7204 Be of the second restriction releasing member  7204 B, thus it is slidably supported. Further, the pin  7204 Ah of the first restriction releasing member  7204 A is inserted into the entrance portion  7204 Bi 1  of the second restriction releasing member  7204 B. At this time, the end portion of the initialization spring  730  and the surface on the back side of the pushed surface  7204 Ai of the first restriction releasing member  7204 A in the direction of the rotational axis A are fixed by adhesive or the like. By this, the first restriction releasing member  7204 A is supported by the second restriction releasing member  7204 B without disengaging in the direction of the rotational axis A. The means by which the first restriction releasing member  7204 A is supported by the second restriction releasing member  7204 B may be replaced with a different structure. For example, a retaining portion may be provided which projects inward in the radial direction r of the imaginary circle VC centered on the rotational axis A from the inner peripheral surface  7204 Be of the second restriction releasing member  7204 B to be engaged with the first restriction releasing member  7204 A. However, in such a case, it is necessary to provide the retaining portion at a position where the retaining portion does not interfere with the center boss  209   d  during the mounting operation of the toner pack  7220  which operation will be described hereinafter. 
     Next, referring to  FIG.  157   , the operation of the restriction releasing mechanism  7204  will be described.  FIG.  157    is a perspective view illustrating the operation of the restriction releasing mechanism  7204 . Part (a) of  FIG.  157    shows a state in which the first restriction releasing member  7204 A has moved in the arrow N direction (downward) relative to the second restriction releasing member  7204 B, and part (b) of  FIG.  157    shows a state in which the first restriction releasing member  7204 A has moved in the arrow U direction (upward). 
     As shown in part (a) of  FIG.  157   , when the first restriction releasing member  7204 A is placed on the arrow N direction side of (below) the second restriction releasing member  7204 B, the pin  7204 Ah is at the entrance portion  7204 Bi 1  the second restriction releasing member  7204 B. When a force F 720  in the arrow U direction (upward) is applied to the pushed surface  7204 Ai in this state, the first restriction releasing member  7204 A is moved in the direction of the arrow U (upward) by the force F 720  against the spring force of the initialization spring  730  (not shown, see  FIG.  156   ). When the first restriction releasing member  7204 A is moved in the direction of the arrow U (upward), the pin  7204 Ah comes into contact with the inclined portion  7204 Bi 2  of the second restriction releasing member  7204 B. Since the inclined portion  7204 Bi 2  is inclined toward the downstream side (in the rotational direction K) and in the arrow U direction (upward) as described above, the first restriction releasing member  7204 A rotates in the rotational direction K. The first restriction releasing member  7204 A rotates in the rotational direction K while moving in the arrow U direction (upward), and therefore, the first restriction releasing portion  7204 Aa also moves similarly. When the first restriction releasing member  7204 A is further moved in the arrow U direction (upward) from this state, the pin  7204 Ah is placed at the straight portion  7204 Bi 3 , so that the rotation of the first restriction releasing member  7204 A in the rotational direction K stops. When the first restriction releasing member  7204 A is further moved in the arrow U direction (upward) from this state, as shown in  FIG.  157   , the result is that the first restriction releasing member  7204 A has moved in the arrow U direction (upward) relative to the second restriction releasing member  7204 B. 
     When the force F 720  on the pushed surface  7204 Ai of the first restriction releasing member  7204 A is removed, the first restriction releasing member  7204 A is subjected to the force F 722  from the initialization spring  730  (not shown, see  FIG.  156   ) to move in the arrow N direction (downward). Then, through the reverse process of the movement of the first restriction releasing member  7204 A in the arrow U direction (upward), the first restriction releasing member  7204 A shown in part (a) of  FIG.  157    is moved in the N direction (downward) relative to the second restriction releasing member  7204 B. 
     The foregoing is the operation of the restriction releasing mechanism  7204 . 
     Next, referring to  FIG.  158   , the operation of mounting the toner pack  7220  on the mounting portion  206  in this modified example will be described.  FIG.  158    is sectional views illustrating a process of releasing the rotation restricting mechanism  212  when the toner pack  7220  is mounted to the mounting portion  206 . Some portions are not shown for the sake of better illustration. The states of part (a) of  FIG.  158    to part ( e ) of  FIG.  158    will be described hereinafter as appropriate. 
     Here, when the toner pack is mounted on the mounting portion, in the basic embodiment, the first restriction releasing member  704 A is rotated by the cut-away portion  704 Ac being acted on by the pin  731   b  of the advancing/retracting member  731 . On the other hand, in this modified example, the first restriction releasing member  7204 A is rotated by the pin  7204 Ah acting on the cut-away portion  7204 Bc of the second restriction releasing member  7204 B. Other operations are the same as in this embodiment. Therefore, only the states shown in part (a) of  FIG.  158    and part ( e ) of  FIG.  158    will be described, and the detailed operation thereof will be omitted. Part (a) of  FIG.  158    shows a state in which the toner pack  7220  is mounted on the mounting portion  206 , and the pushed surface  7204 Ai of the first restriction releasing member  7204 A is brought into contact with the free end portion  209   d   70  of the center boss  209   d  of the apparatus-side shutter  209 . In part (b) of  FIG.  158   , the releasing member  214  is rotated in the rotational direction D by the first restriction releasing member  7204 A, and the second slope  7204 Ba 1  of the second restriction releasing portion  7204 Ba and the second guided surface  214   e   2  of the releasing claw  214   e  are overlapped in the rotational direction D. Part (c) of  FIG.  158    shows a state in which the second guided surface  214   e   2  of the releasing claw  214   e  is rotated in the rotational direction D until it passes the downstream end of the second slope  7204 Ba 1  of the second restriction releasing member  7204 B in the rotational direction D. Part (d) of  FIG.  158    shows a state in which the contact surface  214   a  of the releasing claw  214   e  is in contact with the abutment surface  7204 Ba 3  of the second restriction releasing portion  7204 Ba. In part ( e ) of  FIG.  158   , the second restriction releasing member  7204 B is moved in the arrow G direction, the restricting member  213  is moved in the arrow G direction (upward) together with the releasing member  214 , and the restriction of the rotation of the apparatus-side shutter  209  by the rotation restricting mechanism  212  is released. 
     Modified Example 3 
     In the present embodiment, the first restriction releasing surface  704 Aa 1  of the first restriction releasing member  704 A is structured to abut on the contact surface  214   f  of the releasing member  214 . The first restriction releasing member may be brought into contact with another part of the releasing member  214 . In such a case, a structure can be considered in which the first restriction releasing member abuts to the toner pack side end of the releasing member  214  or the releasing claw  214   e  as an example, referring to  FIGS.  159  to  161    this structure will be described below as a modified example. 
     Referring to  FIG.  159    a restriction releasing mechanism  7304  of this modified example will be described.  FIG.  159    is an exploded perspective view of the restriction releasing mechanism  7304 . The restriction releasing mechanism  7304  of this modified example has different structures in the first restriction releasing member  7304 A and the second restriction releasing member  7304 B of Modified Example 2 of this embodiment, and therefore, the different part thereof will be described. 
     The first restriction releasing member  7304 A is different from the first restriction releasing member  7204 A of Modified Example 2 of this embodiment in the shape of a pair of first restriction releasing portions  7304 Aa and  7304 Ab. Similarly to Modified Example 2 of this embodiment, the pair of first restriction releasing portions  7304 Aa and  7304 Ab have shapes symmetric with respect to the rotational axis A. Therefore, in this modified example, the first restriction releasing portion  7304 Aa will be described, and the description of the first restriction releasing portion  7304 Ab will be omitted. 
     The first restriction releasing portion  7304 Aa projects from the pushed surface  7304 Ai in the direction of the arrow N. A friction member  7304 Aa 1  is provided at the end on the arrow N direction (lower) side. A material such as silicon rubber is used for the friction member  7304 Aa 1 . 
     The second restriction releasing member  7304 B is different from the second restriction releasing member  7204 B of Modified Example 2 of this embodiment in the shapes of the pair of cut-away portions  7304 Bi and  7304 Bj. The pair of cut-away portions  7304 Bi and  7304 Bj have symmetric shapes with respect to the rotational axis A as in Modified Example 2 of this embodiment, and therefore, the cut-away portion  7304 Bi will be described in this modified example, and the description of the cut-away portion  7304 Bj will be omitted. 
     The cut-away portion  7304 Bi comprises an entrance portion  7304 Bi 1 , an inclined portion  7304 Bi 2 , and a straight portion  7304 Bi 3 . The entrance portion  7304 Bi 1  and the inclined portion  7304 Bi 2  have structures similar to those of the entrance portions  7204 Bi 1  and the inclined portion  7204 Bi 2  of Modified Example 3 of this embodiment (see  FIG.  156   ), and therefore, the description thereof will be omitted. 
     The straight portion  7304 Bi 3  is a cut-away portion formed substantially parallel to the rotational axis A in the direction of the arrow U (upward), and is provided in connection with the inclined portion  7304 Bi 2 . Further, a width of the straight portion  7304 Bi 3  measured in the rotational direction K is selected to be larger than a width of the second slope  7304 Ba 1  of the second restriction releasing portion  7304 Ba measured in the rotational direction K. 
     Next, referring to  FIGS.  160  and  161   , the operation of mounting the toner pack  7320  on the mounting portion  206  in this modified example will be described.  FIG.  160    is a cross-sectional view illustrating a process of releasing the rotation restricting mechanism  212  when the toner pack  7320  is mounted to the mounting portion  206 . Some portions are not shown for the sake of better illustration. The states of part (a) of  FIG.  160    to part ( e ) of  FIG.  160    will be described hereinafter as appropriate.  FIG.  161    shows a position of a pin  7304 Ah on the straight portion  7304 Bi 3  when the toner pack  7320  is mounted to the mounting portion  206 . 
     Part (a) of  FIG.  160    shows a state in which the toner pack  7320  is mounted on the mounting portion  206 , and the releasing member  214  is in contact with the friction member  7304 Aa 1  of the first restriction releasing portion  7304 Aa. An end of the releasing member  214  in contact with the friction member  7304 Aa 1  in the arrow G direction (upward direction) is referred to as a contact surface  214   e   70 . At this time, the contact surface  214   e   70  of the releasing member  214  is in a state of entering the friction member  7304 Aa 1  of the first restriction releasing portion  7304 Aa in the direction of arrow G (upward). By this, the first restriction releasing portion  7304 Aa is in a state that a force F 730  is applied to the contact surface  214   e   70  of the releasing member  214 . The force of the initialization spring  730  (not shown, see  FIG.  159   ) acts as the force F 730 . When the toner pack  7320  is further moved in the N direction (downward) of the arrow from this position, the first restriction releasing member  7304 A moves relative to the second restriction releasing member  7304 B in the direction of arrow G (upward) by the reaction force F 732  from the contact surface  214   e   70  of the releasing member  214 . Thus, the first restriction releasing portion  7304 Aa is rotated in the rotational direction D by the action between the pin  7304 Ah of the first restriction releasing member  7304 A and the inclined portion  7304 Bi 2  of the second restriction releasing member  7304 B. When the first restriction releasing portion  7304 Aa rotates in the rotational direction D, a frictional force F 731  due to the force F 730  is produced on the contact surface  214   e   70  of the releasing member  214 . The releasing member  214  is rotated in the rotational direction D by the frictional force F 731 . When the toner pack  7320  is further moved in the arrow N direction (downward) from this state, as shown in part (b) of  FIG.  160   , the second slope  7204 Ba 1  of the second restriction releasing portion  7204 Ba and the second guided surface  214   e   2  of the releasing claw  214   e  are overlapped in the rotational direction D. In addition, the pin  7304 Ah is at the straight portion  7304 Bi 3  of the second restriction releasing member  7304 B. At this time, as shown in  FIG.  161   , the pin  7304 Ah is in the position P 70 , and the downstream side thereof in the rotational direction D is not restricted by the straight portion  7304 Bi 3 . As shown in part (b) of  FIG.  160   , when the toner pack  7320  is further moved in the arrow N direction (downward) from this state, the second slope  7304 Ba 1  of the second restriction releasing portion  7304 Ba is brought into contact with the second guided surface  214   e   2  of the releasing claw  214   e  so that the releasing member  214  rotates in the rotational direction D. At this time, the first restriction releasing portion  7304 Aa receives a frictional force F 734  due to a reaction force F 733  from the contact surface  214   e   70  of the releasing member  214 . Since the pin  7304 Ah is not restricted from rotating in the rotational direction D as described above, the first restriction releasing member  7304 A rotates in the rotational direction D due to the frictional force F 734 . 
     When the toner pack  7320  is further moved in the direction of the arrow N (downward) from this state, as shown in part (c) of  FIG.  160   , the second guided surface  214   e   2  of the releasing claw  214   e  passes the downstream end of the second slope  7304 Ba 1  of the second restriction releasing portion  7304 Ba in the rotational direction D. At this time, the pin  7304 Ah is placed at the position P 71  as shown in  FIG.  161    and is not restricted to the downstream side in the rotational direction E by the straight portion  7304 Bi 3 . 
     When the toner pack  7320  is further moved in the direction of the arrow N (downward) from this state, as shown in part (d) of  FIG.  160   , the third guided surface  214   e   3  of the releasing claw  214   e  passes a flat surface  7304 Ba 2  of the second restriction releasing portion  7304 Ba in the direction of arrow G (upward). Thereafter, the releasing member  214  rotates in the rotational direction E until the contact surface  214   a  of the releasing claw  214   e  abuts to the abutment surface  7304 Ba 3  of the second restriction releasing member  7304 B by the moment M 202  provided by to the releasing spring  216  (not shown, see  FIG.  50   ). At this time, the first restriction releasing portion  7304 Aa receives a frictional force F 736  due to the reaction force F 735  from the contact surface  214   e   70  of the releasing member  214 . Since the pin  7304 Ah is not restricted from rotating in the rotational direction E as described above, the first restriction releasing member  7304 A rotates in the rotational direction E by the frictional force F 736 . Then, as shown in  FIG.  161   , the pin  7304 Ah moves to the position P 72  on the downstream side, in the rotational direction E, of the position P 71 . 
     Thereafter, by moving the second restriction releasing member  7304 B in the arrow G direction as in the basic embodiment of this modified example, the restricting member  213  is moved together with the releasing member  214  in the arrow G direction (upward), and as shown in part (d) of  FIG.  160   , the rotation restriction by the rotation restricting mechanism  212  of the apparatus-side shutter  209  is released. 
     The operation of removing the toner pack  7320  from the mounting portion  206  is the same as that of Embodiment 3, and therefore, the description thereof will be omitted. 
     Embodiment 8 
     Next, referring to  FIGS.  162  to  175   , Embodiment 8 will be described in the following. As compared with the restriction releasing portion of Embodiment 3, this embodiment is different in that the first slope and the second slope of the restriction releasing member are equidistant in the radial direction r of the imaginary circle VC centered on the rotational axis A. In addition, the second slope is movable between a first position the same as the radial position of the first slope in the radial direction r of the imaginary circle VC centered on the rotational axis A, and a second position radially outside the radial direction r relative to the first slope. The description of the same points as in the above-described embodiment will be omitted. In particular, of the elements disclosed in this embodiment, those corresponding to the members described in Embodiments 2 and 3 are assigned the same names as those of the members of Embodiments 2 and 3, and only the points different from Embodiment 3 will be described. 
     (Toner Pack Structure) 
     Referring to  FIGS.  162  to  165   , a toner pack  820  according to this embodiment will be described.  FIG.  162    is an illustration showing the entire toner pack  820  in this embodiment.  FIG.  163    is an exploded perspective view of a restriction releasing member  804  and a shaft ring  335  before being assembled to a nozzle  302 , and is a view as seen from a second end side (nozzle side) in a first direction D 1 .  FIG.  164    is illustrations showing a detailed shape of the restriction releasing member  804 . Part (a) of  FIG.  164    is a view as seen from an orthogonal direction of the first direction D 1 . Part (b) of  FIG.  164    is a view as seen from a second end side (nozzle side) in the first direction D 1 . Part (c) of  FIG.  164    is an enlarged perspective view illustrating the shape of a pushed surface  804   a   7  of the restriction releasing member  804 .  FIG.  165    is sectional views of the restriction releasing member  804 . Part (a) of  FIG.  165    is a sectional view taken along a line X 802 -X 802  shown in part (b) of  FIG.  164   , which is a sectional view taken along the cutting line passing through the rotating axis A and the pushed surface  804   a   7  in the direction of the rotating axis A (central axis). Part (b) of  FIG.  165    is a sectional view taken along a line X 803 -X 803  shown in part (b) of  FIG.  164   , which is a sectional view taken along a cutting line passing through the pushed surface  804   a   7  in a direction perpendicular to the cutting line X 802 -X 802 . 
     As shown in  FIG.  162   , the toner pack  820  in this embodiment comprises an accommodating portion  201  for accommodating toner, a nozzle  302 , and a pack-side shutter  203 , and in addition, a restriction releasing member  804  (projecting portion, protruding portion) partially projecting from an end surface  203   c  of the pack-side shutter  203  in an arrow N direction. 
     Next, referring to  FIGS.  163  to  165   , the restriction releasing member  804  will be described. 
     As shown in  FIG.  163   , the restriction releasing member  804  has a cylindrical shape centered on the rotational axis A and including a cylindrical portion  804   c . A disk-shaped end portion  804   f  is provided at the end of the cylindrical portion  804   c  in the arrow U direction (upward direction) with the rotational axis A as the center. The end portion  804   f  is provided with a hole portion  804   g  centered on the rotational axis A. In addition, the cylindrical portion  804   c  is provided with a pair of projections  804   d  projecting outward in the radial direction r of the imaginary circle VC centered on the rotational axis A. The projections  804   d  constituting the pair have shapes which are 180-degree rotationally symmetric with respect to the rotational axis A. The end of the cylindrical portion  804   c  in the arrow N direction (downward) is referred to as an end portion  804   e , then, the end portion  804   e  is provided with a pair of restriction releasing portions  804   a  (first projection) and  804   b  (second projection) projecting in the arrow N direction (downward). The pair of restriction releasing portions  804   a  and  804   b  have shapes which are 180-degree rotationally symmetric with respect to the rotational axis A. In addition, in the state where the restriction releasing member  804  which will be described hereinafter is assembled to the nozzle  302 , such a restriction releasing portion of the pair of restriction releasing portions  804   a  and  804   b  as is closer to the opening  302   a  of the nozzle  302  in the circumferential direction of the imaginary circle VC is referred to as the restriction releasing portion  804   a.    
     Next, referring to  FIGS.  164  and  165   , the detailed shapes of the pair of restriction releasing portions  804   a  and  804   b  will be described. However, since the paired restriction releasing portions  804   a  and  804   b  have shapes which are 180-degree rotationally symmetric with respect to the rotational axis A as described above, only the restriction releasing portion  804   a  will be described in detail, and the description of the restriction releasing portion  804   b  will be omitted. 
     As shown in part (a) of  FIG.  164   , the restriction releasing portion  804   a  is divided into an upstream side portion and a downstream side portion in the rotational direction K by a slit  804   a   6  extending in the arrow N direction (downward) from the end portion  804   e . An upstream portion in the rotational direction K is referred to as an upstream restriction releasing portion  804   a   9 , and a portion downstream in the rotational direction K is referred to as a downstream restriction releasing portion  804   a   10 . 
     The upstream restriction releasing portion  804   a   9  comprises a first slope  804   a   1  (first downward surface, first downward guide surface, first downward force applying surface, first downward push surface) and a first abutment surface  804   a   12 . 
     The first slope  804   a   1  is provided on the downstream side in the rotational direction K of the upstream side restriction releasing portion  804   a   9  and at the end portion in the arrow N direction (downward). The first slope  804   a   1  is a surface extending so as to go in the arrow U direction (upward) as goes in the rotational direction K (first rotational direction) and is a surface facing the arrow N direction (downward). 
     The first abutment surface  804   a   12  is a surface parallel to the rotational axis A, and is provided at the downstream end portion of the first slope  804   a   1  in the rotational direction K. The first abutment surface  804   a   12  is a surface extending in the direction of the rotational axis A. 
     The downstream restriction releasing portion  804   a   10  comprises a second slope  804   a   2  (second downward surface, second downward guide surface, second force applying surface, second push surface), a flat surface  804   a   3  (upward surface, upward engaging surface, upward push surface, upward force applying surface), a second abutment surface  804   a   4 , and a deformed portion  804   a   5 , and in addition, the pushed surface  804   a   7  and a projection  804   a   8  shown in part (b) of  FIG.  164   . 
     The second slope  804   a   2  is provided at the end of the downstream restriction releasing portion  804   a   10  in the direction of the arrow N (downward). The second slope  804   a   2  is a surface extending so as to go in the arrow U direction (upward) as goes in the rotational direction K, and is a surface facing the arrow N direction (downward). In addition, the second slope  804   a   2  and the first slope  804   a   1  are provided so as to be equidistant in the radial direction r (see part (b) of  FIG.  164   ) of the imaginary circle VC centered on the rotational axis A. In other words, the second slope  804   a   2  and the first slope  804   a   1  is provided so as to be at the same position in the radial direction r (part (b) of  FIG.  164   ). That is, the second slope  804   a   2  and the first slope  804   a   1  are provided in the same distant region in the radial direction r from the rotational axis A. Although the second slope  804   a   2  in this embodiment is shown in the Figure as being flush with the first slope  804   a   1 , at lease a part of it may be off-set in the arrow N direction (downward) or the arrow U direction (upper side) with respect to the first slope  804   a   1 . 
     The flat surface  804   a   3  is a surface perpendicular to the rotational axis A and facing in the arrow U direction (upward). In addition, the flat surface  804   a   3  is placed on the arrow U direction side of (above) at least a part of the second slope  804   a   2 . 
     The second abutment surface  804   a   4  is on the upstream side of the flat surface  804   a   3  in the rotational direction K, extends in the arrow U direction (upward) from the flat surface  804   a   3  to the end portion  804   e , and faces the downstream side in the rotational direction K. 
     The deformed portion  804   a   5  is a portion of the downstream side restriction releasing portion  804   a   10  from the end portion  804   e  to the flat surface  804   a   3  in the rotational axis A direction. 
     As shown in part (c) of  FIG.  164   , the pushed surface  804   a   7  is on the upstream side of at least a part of the second slope  804   a   2  in the rotational direction K and inside thereof in the radial direction r of the imaginary circle VC centered on the rotational axis. As shown in part (a) of  FIG.  165   , the pushed surface  804   a   7  extends so as to go inward in the radial direction r of the imaginary circle VC centered on the rotational axis A as goes in the arrow U direction (upward) and is inclined so as to go in the direction of arrow N (downward) as goes toward the downstream side in the rotational direction K, as shown in part (b) of  FIG.  165   . 
     As shown in part (a) of  FIG.  165   , the projection  804   a   8  projects from the inner peripheral surface  804   a   11  inward in the radial direction r of the imaginary circle VC centered on the rotational axis A, and is provided on the deformed portion  804   a   5 . In addition, the end surface of the projection  804   a   8  in the arrow N direction (lower surface) is a surface so as to go radially inward of the imaginary circle VC centered on the rotational axis A as goes in the direction of the arrow U (upward). 
     (Assembling of Toner Pack) 
     Next, referring to  FIGS.  163  and  166   , the assembling of the toner pack  820  in this embodiment will be described.  FIG.  166    is a sectional view of the toner pack  820  taken along a line X 801 -X 801  shown in  FIG.  162   , which is along the pin  310  with the rotational axis A as the center. The pack-side seal  205  (see  FIG.  56   ) is not shown. 
     As shown in  FIG.  163   , in the toner pack  820 , the shaft ring  334  is assembled to the shaft member  331  by the same assembling method as in Embodiment 3. Thereafter, the hole portion  804   g  of the restriction releasing member  804  is fitted on the small diameter shaft portion  331   c  of the shaft member  331  in the direction of the arrow U (upward). At this time, the cylindrical portion  804   c  of the restriction releasing member  804  is inserted into the cylindrical support portion  302   b  of the nozzle  302 . In addition, the projection  804   d  of the restriction releasing member  804  is inserted into the cut-away portion  302   c  of the nozzle  302 . By engaging the projection  804   d  of the restriction releasing member  804  with the cut-away portion  302   c , the restriction releasing member  804  is restricted in the movement around the rotational axis A relative to the nozzle  302 . Therefore, the restriction releasing member  804  is supported movably only in the direction of the rotational axis A relative to the nozzle  302 . Thereafter, in the toner pack  820 , the shaft ring  335  is assembled to the small diameter shaft portion  331   c  of the shaft member  331  by the same assembly method as in Embodiment 3. 
     Here, as shown in  FIG.  166   , the hole through which the restriction releasing member  804  of the end surface  203   c  of the pack side shutter  203  passes is referred to as the hole portion  203   c   80 . At this time, in the radial direction r of the imaginary circle VC centered on the rotational axis A, a radius R 81  of the hole portion  203   c   80  of the pack side shutter  203  is larger than a maximum radius R 80  of the downstream side restriction releasing portion  804   a   10  of the restriction releasing member  804 . This prevents interference when the second slope  804   a   2  of the restriction releasing member  804  moves from the first position to the second position outside in the radial direction r of the imaginary circle VC centered on the rotational axis A, as will be described hereinafter. 
     (Operation of Restriction Releasing Member) 
     Referring to part (b) of  FIG.  164   , the operation of the restriction releasing member  804  will be described. 
     In the initial state, the restriction releasing portion  804   a  is placed at the first position where the second slope  804   a   2  is equally distant with the first slope  804   a   1  in the radial direction r of the imaginary circle VC centered on the rotational axis A. From this state, the deformed portion  804   a   5  is deformed by applying a force in the radial direction r to the downstream restriction releasing portion  804   a   10 . By this, as shown by the broken line in the Figure, the second slope  804   a   2  of the restriction releasing portion  804   a  moves to the second position outside the first slope  804   a   1  in the radial direction r. The details of the force applied to the restriction releasing portion  804   a  will be described in the description of mounting/dismounting the toner pack. That is, the second slope  804   a   2  is movable between the first position at the same position as the first slope  804   a   1  in the radial direction r and the second position outside the first slope  804   a   1  in the radial direction r. The second slope  804   a   2  is in the first position when the toner pack  820  is not mounted on the mounting portion  206 . 
     When the force applied to the restriction releasing portion  804   a  is removed, the deformed portion  804   a   5  is restored the deformed state. Then, the second slope  804   a   2  shown by the solid line in the Figure moves to the first position which is equally distant, in the radial direction r, as the first slope  804   a   1 . 
     (Mounting and Dismounting of Toner Pack) 
     Next, referring to  FIGS.  167  to  172   , mounting/dismounting of the toner pack  820  to/from the mounting portion  206  will be described. In the mounting/dismounting operation, only the operation different from that of Embodiment 3 will be described.  FIGS.  167  to  172    show a process in which the restriction releasing member  804  releases the rotation restricting mechanism  212  when the toner pack  820  is mounted to the mounting portion  206 . The pack-side shutter  203  is not shown for the sake of better illustration. The detailed states of  FIGS.  167  to  172    will be appropriately described together with the description of the operation. Part (b) of  FIG.  168    shows a sectional view taken along a line X 804 -X 804  of part (a) of  FIG.  168   . Part (c) of  FIG.  168    shows a sectional view taken along a line X 809 -X 809  of part (b) of  FIG.  168   . Part (b) of  FIG.  169    is a sectional view taken along a line X 806 -X 806  of part (a) of  FIG.  169   , part (b) of  FIG.  170    is a sectional view taken along a line of X 805 -X 805  of part (a) of  FIG.  170   , and part (b) of  FIG.  171    is a sectional view taken along a line an X 808 -X 808  of part (a) of  FIG.  171   . 
     First, when the toner pack  820  is mounted on the mounting portion  206 , the second slope  804   a   2  of the restriction releasing member  804  is in the first position in a situation that the restriction releasing member  804  is not in contact with the restriction releasing member  214  of the mounting portion  206 .  FIG.  167    shows a state in which the toner pack  820  is moved in the N direction (downward) of the arrow, and the first slope  804   a   1  of the restriction releasing portion  804   a  and the first guided surface  214   e   1  of the releasing claw  214   e  are in contact with each other. At this time, the slit  804   a   6  of the restriction releasing portion  804   a  is placed on the downstream side, in the rotational direction D, of the eave portion  210   n  of the cover  210 . When the toner pack  820  is further moved in the direction of the arrow N from this stage, the releasing member  214  is rotated in the rotational direction D (first rotational direction) against the urging force of the releasing spring  216  (not shown) by the first guided surface  214   e   1  being pressed against the first slope  804   a   1 , as in Embodiment 3. 
     Here, at least a part of the pushed surface  804   a   7  is placed at the position on the arrow U direction side (upper side) with respect to the first slope  804   a   1  and the second slope  804   a   2  (see part (a) of  FIG.  165   ). In addition, there is a space S 80  in the direction of the arrow N (downward) of the pushed surface  804   a   7  (see part (a) of  FIG.  165   ). Further, the end portion of the releasing claw  214   e  in the arrow G direction (upward direction) and the downstream end portion in the rotational direction D are referred to as the push surface  214   e   80 . When the toner pack  820  is further moved in the direction of the arrow N from this state, the first guided surface  214   e   1  of the releasing claw  214   e  passes the downstream end in the rotational direction D of the first slope  804   a   1  of the restriction releasing portion  804   a . Thereafter, the releasing claw  214   e  enters the space S 80  (see part (b) of  FIG.  168   ). At this time, as shown in  FIG.  168   , the push surface  214   e   80  of the releasing claw  214   e  and the pushed surface  804   a   7  of the downstream restriction releasing portion  804   a   10  are in contact with each other. In this state, since the releasing claw  214   e  is not in contact with the first slope  804   a   1  and the second slope  804   a   2  of the restriction releasing portion  804   a , it is not rotated any more in the rotational direction D. At this time, as in Embodiment 3, the releasing member  214  of the releasing claw  214   e  is rotated in the rotational direction E by the urging force of the releasing spring  216  (not shown). Then, as the releasing member  214  rotates in the rotational direction E, the contact surface  214   f  abuts to the first abutment surface  804   a   12  of the restriction releasing portion  804   a  in the rotational direction E. 
     When the toner pack  820  is further moved in the direction of the arrow N from this state, the pushed surface  804   a   7  of the downstream restriction releasing portion  804   a   10  receives a force F 800  perpendicular to the pushed surface  804   a   7  from the push surface  214   e   80  of the releasing claw  214   e . At this time, as shown in part (b) of  FIG.  168   , the force F 800  received by the pushed surface  804   a   7  from the push surface  214   e   80  of the releasing claw  214   e  includes a component in the radial direction r of the imaginary circle VC centered on the rotational axis A. Therefore, the force F 800  elastically deforms the downstream restriction releasing portion  804   a   10  in the direction toward the outside in the radial direction r. Further, as shown in part (c) of  FIG.  168   , the force F 800  received by the pushed surface  804   a   7  of the downstream restriction releasing portion  804   a   10  from the push surface  214   e   80  of the releasing claw  214   e  includes a rotational direction D component. On the other hand, a reaction force F 801  produced on the push surface  214   e   80  of the releasing claw  214   e  includes the rotational direction E component. The reaction force F 801  causes the releasing claw  214   e  to bring the contact surface  214   f  into contact with the first abutment surface  804   a   12  of the restriction releasing portion  804   a . Therefore, the releasing claw  214   e  is in a state where the rotation is restricted in the rotational direction D. 
     When the toner pack  820  is further moved in the direction of arrow N from this position, the deformed portion  804   a   5  of the downstream restriction releasing portion  804   a   10  shown in part (b) of  FIG.  168    is deformed toward the outside of the radial direction r by the force F 800 . By this, the second slope  804   a   2  of the downstream restriction releasing portion  804   a   10  moves from the first position to the second position. 
     When the toner pack  820  is further moved in the direction of the arrow N (downward) from this state, as shown in part (a) of  FIG.  169   , the second slope  804   a   2  of the downstream restriction releasing portion  804   a   10  moved to the second position and the second guided surface  214   e   2  of the releasing claw  214   e  are brought into contact with each other. In this state, as shown in part (b) of  FIG.  169   , the inner peripheral surface  804   a   11  of the downstream restriction releasing portion  804   a   10  is in contact with the releasing claw  214   e . This is because the contact point between the downstream restriction releasing portion  804   a   10  and the releasing claw  214   e  moves from the pushed surface  804   a   7  to the inner peripheral surface  804   a   11  as the toner pack  820  moves in the direction of the arrow N (downward). By this, the downstream restriction releasing portion  804   a   10  receives the force F 802  including the radial r component. The downstream side restriction releasing portion  804   a   10  maintains the deformation of the deformed portion  804   a   5  in the radial direction r by the force F 802  from the releasing claw  214   e . Therefore, the second slope  804   a   2  of the downstream restriction releasing portion  804   a   10  is maintained at the second position. Further, since the releasing claw  214   e  is released from the contact between the push surface  214   e   80  and the pushed surface  804   a   7  of the downstream restriction releasing portion  804   a   10  (see part (c) of  FIG.  168   ), the releasing claw  214   e  can move in the rotational direction D. 
     When the toner pack  820  is further moved in the direction of the arrow N from the state of part (a) of  FIG.  169   , the releasing claw  214   e  of the releasing member  214  is pressed to the second slope  804   a   2  of the downstream side restriction releasing portion  804   a   10 , similarly to Embodiment 3. By the releasing claw  214   e  being pressed, the releasing member  214  moves in the rotational direction D against the urging force of the releasing spring  216  (not shown). Then, as shown in part (a) of  FIG.  170   , the second guided surface  214   e   2  of the releasing claw  214   e  passes the downstream end of the second slope  804   a   2  of the downstream side restriction releasing portion  804   a   10  in the rotational direction D. In addition, the releasing claw  214   e  is completely on the downstream side, in the rotational direction D, of the downstream side restriction releasing portion  804   a   10 . At this time, as shown in part (b) of  FIG.  170   , in the downstream side restriction releasing portion  804   a   10 , the projection  804   a   8  provided on the inner peripheral surface  804   a   11  abuts on the center boss  209   d  of the apparatus-side shutter  209  in the radial direction r. By this, even if the contact state between the inner peripheral surface  804   a   11  of the downstream restriction releasing portion  804   a   10  and the releasing claw  214   e  (not shown) in the radial direction r is lost, the deformation of the downstream restriction releasing portion  804   a   10  is maintained. For this reason, the second slope  804   a   2  of the downstream restriction releasing portion  804   a   10  maintains the second position. 
     When the toner pack  820  is further moved in the arrow N direction from the state shown in part (a) of  FIG.  170   , the third guided surface  214   e   3  of the releasing claw  214   e  passes the flat surface  804   a   3  of the downstream side restriction releasing portion  804   a   10  in the arrow N direction (downward). And, the releasing claw  214   e  rotates in the rotational direction E (second rotational direction) by the moment M 202  (urging force) produced by the releasing spring  216  (not shown). Then, as shown in part (a) of  FIG.  171   , the contact surface  214   a  of the releasing claw  214   e  is in contact with the second abutment surface  804   a   4  of the downstream restriction releasing portion  804   a   10 . At this time, as shown in part (b) of  FIG.  171   , the projection  804   a   8  of the downstream side restriction releasing portion  804   a   10  maintains the contact state with the center boss  209   d  of the apparatus-side shutter  209 . By this, the deformed portion  804   a   5  of the downstream restriction releasing portion  804   a   10  is maintained in the radial direction r. Therefore, the second slope  804   a   2  of the downstream restriction releasing portion  804   a   10  maintains the second position. In addition, the flat surface  804   a   3  of the downstream restriction releasing portion  804   a   10  is also placed at the second position in the radial direction r. By this, the surface of the releasing claw  214   e  connected to the downstream end of the third guided surface  214   e   3  in the rotational direction K is referred to as the lower surface  214   e   81  (see also part (a) of  FIG.  171   ), and the flat surface  804   a   3  of the downstream restriction releasing portion  804   a   10  and the lower surface  214   e   81  become able to face each other. 
     Thereafter, the operation is the same as that of Embodiment 3, and therefore, detailed description thereof will be omitted, but by operating the operating member  330  (see  FIG.  104   ), the restriction releasing member  804  is moved in the direction of the arrow G, and the releasing claw  214   e  is moved in the direction of arrow G. That is, the flat surface  804   a   3  of the downstream side restriction releasing portion  804   a   10  functions as a force applying surface for applying a force for lifting the releasing member  214  upward to the lower surface  214   e   81  of the releasing claw  214   e . By this, as shown in  FIG.  172   , the restricting member  213  is moved in the direction of arrow G (upward) together with the releasing member  214 , and the rotation restriction by the rotation restricting mechanism  212  of the apparatus-side shutter  209  is released. By the above-described operation, the toner pack  820  mounting is completed. 
     Further, the operation of removing the toner pack  820  from the mounting portion  206  is the same as that of Embodiment 3, and therefore, the description thereof will be omitted. When the removal of the toner pack  820  is completed, the downstream restriction releasing portion  804   a   10  is restored from the deformed state, and the second slope  804   a   2  is in a state of being moved to the first position. 
     Modified Example 1 
     In this embodiment, the upstream restriction releasing portions  804   a   9 ,  804   b   9  and the downstream restriction releasing portions  804   a   10 ,  804   b   10  of the restriction releasing member  804  are parts of one member and are separated by slits  804   a   6  and  804   b   6 . However, the present invention is not limited to such an example, and the upstream side restriction releasing portion  804   a   9  and the downstream side restriction releasing portion  804   a   10 ,  804   b   10  may be separate members. In this case, a structure in which the downstream restriction releasing portion having the deformable portion is a separate portion can be considered as an example. Referring to  FIG.  173   , this structure will be described below as a modified example. 
       FIG.  173    is a perspective view of the restriction releasing member  8104  in this modified example, (a) thereof shows an assembled state, and (b) thereof shows a disassembled state. As shown in part (a) of  FIG.  173   , in the restriction releasing member  8104  in this modified example, a first restriction releasing member  8104 Ba including a downstream side restriction releasing portion  8104 Ba 10  a second restriction releasing member  8104 Bb including a downstream side restriction releasing portion  8104 Bb 10  are connected with a main assembly member  8104 A including upstream restriction releasing portions  8104 Aa 9  and  8104 Ab 9 . As shown in part (b) of  FIG.  173   , the first restriction releasing member  8104 Ba is provided with an engaging portion  8104 Ba 20  on the arrow U direction side (thereabove). Similarly, the second restriction releasing member  8104 Bb is provided with an engaging portion  8104 Bb 20  on the arrow U direction side (thereabove). The engaging portion  8104 Ba 20  of the first restriction releasing member  8104 Ba and the engaging portion  8104 Bb 20  of the second restriction releasing member  8104 Bb are engaged with the groove portion  8104 Ac provided in the main assembly member  8104 A and fixed by means such as adhesion or press fitting. 
     Here, the upstream side restriction releasing portion  8104 Aa 9  and the downstream side restriction releasing portion  8104 Ba 10 , the upstream side restriction releasing portion  8104 Ab 9  and the downstream side restriction releasing portion  8104 Bb 10  are symmetric with respect to the rotational axis A (central axis). Therefore, the upstream side restriction releasing portion  8104 Aa 9  and the downstream side restriction releasing portion  8104 Ba 10  will be described, and the description of the upstream side restriction releasing portion  8104 Ab 9  and the downstream side restriction releasing portion  8104 Bb 10  will be omitted. 
     The upstream side restriction releasing portion  8104 Aa 9  has a first abutment surface  8104 Aa 12  as in this embodiment which is a base embodiment of this modified example. The other structures of the upstream side restriction releasing portion  8104 Aa 9  are the same as those in this embodiment, and therefore, the description thereof will be omitted. 
     The downstream side restriction releasing portion  8104 Ba 10  has a second slope  8104 Ba 2  and a deformed portion  8104 Ba 5  as in the base embodiment, and the second slope  8104 Ba 2  can be moved to the first position and the second position as in the base embodiment. 
     Further, in a state in which the second slope  8104 Ba 2  is in the first position, an end surface of the downstream side restriction releasing portion  8104 Ba 10  facing the first abutment surface  8104 Aa 12  of the upstream side restriction releasing portion  8104 Aa 9  in the rotational direction K is the end surface  8104 Ba 13 . The other structures of the downstream side restriction releasing portion  8104 Ba 10  are the same as those in the base embodiment, and therefore, the description thereof will be omitted. 
     In a state where the second slope  8104 Ba 2  is in the first position, the first abutment surface  8104 Aa 12  and the end surface  8104 Ba 13  are in contact with each other. That is, there is no gap corresponding to the slit of the base embodiment. 
     The above-described structure is peculiar to this modified example, and other structures are the same as those of the above-described embodiment. 
     Therefore, the description of the operation of the second slope  8104 Ba 2  moving from the first position to the second position and the description of the mounting/dismounting of the toner pack  820  with the movement of the toner pack  820  in the arrow N direction are omitted. 
     In this modified example, materials different from that of the main assembly member  8104 A can be applied to the first restriction releasing member  8104 Ba and the second restriction releasing member  8104 Bb as compared with the base embodiment. It is possible that a material having high rigidity is used for the main assembly member  8104 A, and a material having toughness and having advantages for elastic deformation is used for the first restriction releasing member  8104 Ba and the second restriction releasing member  8104 Bb. 
     As compared with the base embodiment of this modified example, this modified example has no slit (gap) between the first restriction releasing member  8104 Ba and the second restriction releasing member  8104 Bb and the main assembly member  8104 A in the rotational direction K. That is, in the state that the second slopes  8104 Ba 2  and  8104 Bb 2  in the first position, the first restriction releasing member  8104 Ba and the second restriction releasing member  8104 Bb are supported by the main assembly member  8104 A. 
     Therefore, it is possible to reduce the risk of damage when an unexpected external force is applied to the first restriction releasing member  8104 Ba and the second restriction releasing member  8104 Bb inadvertently by the user. In addition, the free end positions of the first restriction releasing member  8104 Ba and the second restriction releasing member  8104 Bb, which are elongated in the rotational axis A direction, can be protected from being displaced, and therefore, the mounting operation is further stabilized. 
     As for the method of dividing each of the restriction releasing portions, the base embodiment and this modified example may be appropriately selected according to the processing technique to be used. 
     Modified Example 2 
     In the base embodiment, the upstream restriction releasing portion  804   a   9  and the downstream restriction releasing portion  804   a   10  of the restriction releasing member  804  are divided in the rotational direction K by the slit  804   a   6 . However, the present invention is not limited to such an example, and at least parts of the upstream side restriction releasing portion  804   a   9  and of the downstream side restriction releasing portion  804   a   10  may overlap in the rotational direction K. Referring to  FIG.  174   , such a structure will be described in the following as an example of this modified example. 
       FIG.  174    is a view of a restriction releasing member in this modified example as viewed from a second end side (nozzle side) of a first direction D 1 , wherein part (a) shows a restriction releasing member  8204  and part (b) shows another structure of the restriction releasing member  82104 . 
     Referring to part (a) of  FIG.  174   , the structure of the restriction releasing member  8204  will be described. In the restriction releasing member  8204 , the first end portion  8204   a   13  on the downstream side in the rotational direction K of the upstream side restriction releasing portion  8204   a   9  and the second end portion  8204   a   14  on the upstream side in the rotational direction K of the downstream side restriction releasing portion  8204   a   10  overlap in the rotational direction K. In addition, the second end portion  8204   a   14  of the downstream side restriction releasing portion  8204   a   10  is outside the first end portion  8204   a   13  of the upstream side restriction releasing portion  8204   a   9  in the radial direction r of the imaginary circle VC centered on the rotational axis A (central axis). Further, the slit  8204   a   6  is inclined so as to go in the direction opposite to the radial direction r as goes in the rotational direction K. By this, the downstream side restriction releasing portion  8204   a   10  can be deformed in the radial direction r. 
     Referring to part (b) of  FIG.  174   , the structure of the restriction releasing member  82104  will be described. The restriction releasing member  82104  is provided with a first end portion  82104   a   13  on the downstream side, in the rotational direction K, of the upstream side restriction releasing portion  82104   a   9 , and a first end portion  82104   a   15  on the upstream side, in the rotational direction K, of the downstream side restriction releasing portion  82104   a   10 . In addition, the upstream side restriction releasing portion  82104   a   9  has a second end portion  82104   a   14  recessed toward the upstream side in the rotational direction K, on an outside of the first end portion  82104   a   13  in the radial direction r. Further, the downstream side restriction releasing portion  82104   a   10  has a second end portion  82104   a   16  projecting toward the upstream side in the rotational direction K, on an outside of the first end portion  82104   a   15  in the radial direction r. 
     The first end portion  82104   a   13  of the upstream side restriction releasing portion  82104   a   9  and the first end portion  82104   a   15  of the downstream side restriction releasing portion  82104   a   10  are opposed and are close to each other in the rotational direction K. In addition, the second end portion  82104   a   14  of the upstream side restriction releasing portion  82104   a   9  and the second end portion  82104   a   16  of the downstream side restriction releasing portion  82104   a   10  are opposed and are close to each other in the rotational direction K. By this, the upstream side restriction releasing portion  82104   a   9  and the downstream side restriction releasing portion  82104   a   10  are partially overlapped in the rotational direction K and in the radial direction r. Also in this structure, the downstream side restriction releasing portion  82104   a   10  can be deformed in the radial direction r. 
     In this modified example, similarly to Modified Example 1 of the base embodiment, if it is difficult to process the slit, the upstream side restriction releasing portion and the downstream side restriction releasing portion may be made as separate portions. 
     Modified Example 3 
     In Modified Example 2 of this base embodiment, the upstream side restriction releasing portions  8204   a   9  and  82104   a   9  and the downstream side restriction releasing portions  8204   a   10  and  82104   a   10  are partly overlapped in the radial direction r and the rotational direction K of the imaginary circle VC centered on the rotational axis A. The present invention is not limited to such an example, the upstream side restriction releasing portion  804   a   9  and the downstream side restriction releasing portion  804   a   10  may be structured to overlap the rotational direction K with respect to the direction of the rotational axis A (central axis). Referring to  FIG.  175   , the structure in this case will be described in the following as such a modified example. 
       FIG.  175    is an illustration of a restriction releasing member in this modified example, wherein part (a) shows a restriction releasing member  8304 , part (b) show the a restriction releasing member  83104  having a different structure, and part (c) is an another different structure of the restriction releasing member  83204 . 
     Referring to part (a) of  FIG.  175   , the structure of the restriction releasing member  8304  will be described. The slit  8304   a   6  (consisting of a gap of about 0.2 to 0.5) of the restriction releasing member  8304  goes in the rotational direction K as goes the in the direction of the arrow U (upward). By this, the upstream side restriction releasing portion  8304   a   9  and the downstream side restriction releasing portion  8304   a   10  are structured to overlap with each other in the rotational direction K. 
     Referring to part (b) of  FIG.  175   , the structure of the restriction releasing member  83104  will be described. The slit  83104   a   6  (consisting of a gap of about 0.2 to 0.5) of the restriction releasing member  83104  extends so as to go in the rotational direction K as goes in the direction of the arrow N (downward). By this, the upstream side restriction releasing portion  83104   a   9  and the downstream side restriction releasing portion  83104   a   10  are structured to overlap with each other in the rotational direction K. 
     Referring to part (c) of  FIG.  175   , the structure of the restriction releasing member  83204  will be described. The slit  83204   a   6  (consisting of a gap of about 0.2 to 0.5) of the restriction releasing member  83204  extends so as to snake upstream and downstream in the rotational direction K as goes in the direction of the arrow U (upward). By this, the upstream side restriction releasing portion  83204   a   9  and the downstream side restriction releasing portion  83204   a   10  are structured to overlap with each other in the rotational direction K. 
     In this modified example, as in Modified Example 1 of this embodiment, if it is difficult to process the slit, the upstream side restriction releasing portion and the downstream side restriction releasing portion may be made as separate portions. 
     Embodiment 9 
     Next, referring to  FIGS.  176  to  182   , another structure will be described. The same points as those of the above-described embodiments and modified examples will be omitted. In particular, of the elements disclosed in this embodiment, those corresponding to the above-mentioned members will be assigned the same names as the above-mentioned members, and only the points different from the above-mentioned members will be described. 
     In Embodiment 2, the structure of a toner pack in which a projection is provided on the nozzle has been described. In this modified example, a structure in which a projection is provided on a rotatable member which is rotatable relative to the nozzle, not on the nozzle, will be described. This will be described in the following. 
     Referring to  FIGS.  176 ,  177 ,  178 , and  179   , the structure of a toner pack  920  will be described.  FIG.  176    is a perspective view of the toner pack  920  having the structure of this embodiment.  FIG.  177    is an exploded perspective view of the toner pack  920 .  FIG.  178    is an exploded perspective view of the nozzle of this embodiment, and part (a) of  FIG.  178    and part (b) of  FIG.  178    are exploded perspective views a seen in different directions.  FIG.  179    is an exploded perspective view of the pack-side shutter of this embodiment, and part (a) of  FIG.  179    and part (b) of  FIG.  179    are exploded perspective views as seen in different directions. 
     As shown in  FIGS.  176  and  177   , the toner pack  920  comprises an accommodating portion  901  (first accommodating portion), a connecting ring  930 , a shutter portion  903 A (rotatable member), an opening seal  931 , a first nozzle portion  902 A, the second nozzle portion  902 B, a shutter seal  922 , and a projecting portion unit  903 B, in this order from the first end side in the first direction D 1 . A shutter unit  903  assembled so that the shutter portion  903 A and the projecting portion unit  903 B are integrated with the nozzle  902  (discharge portion) including the first nozzle portion  902 A and the second nozzle portion  902 B which are assembled to be integral with each other, is rotatable around the rotational axis A (central axis). 
     The connecting ring  930  has a generally cylindrical shape coaxial with the rotational axis A, and the accommodating portion  901  is connected to the outer peripheral portion  930   b  with hermetical sealing. The shutter portion  903 A is connected to the connecting ring  930  from the second end portion side in the first direction D 1 . The connecting ring  930  and the shutter portion  903 A are integrally coupled. 
     As shown in  FIG.  178   , the shutter portion  903 A has a generally cylindrical shape coaxial with the rotational axis A, and includes an end surface  903 Aa, a cylindrical portion  903 Ab, and an end surface  903 Ac perpendicular to the rotational axis A and provided on the second end side in the first direction D 1 , in this order in the first direction D 1  from the first end portion side. The shutter portion  903 A is provided with a through hole  903 Ad penetrating in the first direction D 1 . The through hole  903 Ad has a sector shape centered on the rotational axis A, and the sector angle thereof V 90  is at about 75°. A hollow flat plate-shaped opening seal  931  is mounted to the through hole  903 Ad from the second end side in the first direction D 1  by adhesion. The opening seal  931  is made of an elastic sponge or the like, and is provided so as to surround the sector-shaped through hole  903 Ad. 
     The end surface  903 Aa is provided with a cylindrical recess  903 Ag which is substantially coaxial with the rotational axis A recessed toward the second end side in the first direction D 1 . A surface  903 Ah is provided at the bottom portion of the recess  903 Ag. The surface  903 Ah is a surface inclined toward the second end portion side of the first direction D 1  as goes toward the through hole  903 Ad. 
     In addition, the end surface  903 Ac is provided with two-sided recess portions  903 Ae coaxial with the rotational axis A and recessed toward the first end portion in the first direction D 1 . A surface  903 Af perpendicular to the rotational axis A is provided at the bottom portion of the recess  903 Ae. 
     As shown in  FIG.  179   , the first nozzle portion  902 A has a hollow cylindrical shape coaxial with the rotational axis A, and includes an end surface  902 Aa and a first cylindrical portion  902 Ah and a disk portion  902 Ab having a diameter larger than that of the first cylindrical portion  902 Ah and a second cylinder portion  902 Ac having a diameter smaller than that of the disk portion  902 Ab provided coaxially with the rotational axis A, in this order from the first end side in the first direction D 1 , and an end surface  902 Af is provided on the second end side of the first direction D 1 . In addition, the first nozzle portion  902 A is provided with a through hole  902 Ae coaxial with the rotational axis A. Further, a through hole  902 Ad, which is a sector-shaped through hole centered on the rotational axis A is provided. The end surface  902 Aa is provided with a cylindrical recess  902 Am coaxial with the rotational axis A and recessed toward the second end in the first direction D 1 , and a surface  902 Ak perpendicular to the rotational axis A at the bottom portion of the recess  902 Am. In addition, the end surface  902 Af is provided with a D-cut recess  902 Ag on the first end side in the first direction D 1 , and the bottom portion of the recess  902 Ag is provided with a surface  902 An perpendicular to the rotational axis A. 
     In the second nozzle portion  902 B, a hollow outer cylindrical portion  902 Ba and an inner cylindrical portion  902 Bb which are coaxial with the rotational axis A are connected by an end surface  902 Bc placed on the second end side in the first direction D 1 . On the outer surface of the outer cylindrical portion  902 Ba, a recess  902 Bj recessed inside in the radial direction r of the imaginary circle VC is provided. The recess  902 Bj is structured to engage with the drive transmission portion  208   a  of the operating lever  208  and the driven transmission portion  209   e  of the apparatus-side shutter  209 , when the toner pack  920  is mounted to the mounting portion  206 . 
     The inner cylindrical portion  902 Bb is provided with an end surface  902 Be on the first end portion side in the first direction D 1 . The outer peripheral portion  902 Bf of the end surface  902 Be has a D-cut shape, is fitted into the recess  902 Ag of the first nozzle portion  902 A from the second end side in the first direction D 1 , and the end surface  902 Be abuts to the surface  902 An of the first nozzle portion  902 A, and the second nozzle portion  902 B is fixed to the first nozzle portion  902 A by adhesive. 
     The end surface  902 Be is provided with a recess  902 Bd recessed toward the second end side in the first direction D 1 . In addition, the side surface portion  902 Bh of the inner cylindrical portion  902 Bb is provided with a discharge opening  902 Bk which is in fluid communication with the recess  902 Bd and is directed to the outside in the radial direction r of the imaginary circle VC centered on the rotational axis A. The recess  902 Bd is a toner passage leading to the discharge opening  902 Bk. A discharge seal  933  is mounted on the side surface portion  902 Bh of the second nozzle portion  902 B. The discharge seal  933  has a hollow flat plate shape, and is mounted by adhesive along the side surface portion  902 Bh so that the through hole portion  933   a  surrounds the discharge opening  902 Bk. The discharge seal  933  is made of an elastic sponge. The recess  902 Bj of the outer cylindrical portion  902 Ba is provided on the outer surface on the opposite side of the discharge opening  902 Bk with the rotational axis A interposed therebetween. 
     The end surface  902 Bc is provided with a first recess portion  902 Bg having a cylindrical shape which is coaxial with the rotational axis A and which is recessed toward the first end portion in the first direction D 1 . In addition, a second recess portion  902 Bp having a cylindrical recess shape which has a diameter smaller than that of the first recess portion  902 Bg and which is coaxial with the rotational axis A, is provided on the first end side, in the first direction D 1 , of the first recess portion  902 Bg. The first recess portion  902 Bg and the second recess portion  902 Bp are connected by a surface  902 Bn which is a flat surface perpendicular to the rotational axis A. Further, the second nozzle portion  902 B is provided with a through hole  902 Bm penetrating in the first direction D 1  coaxially with the rotational axis A. 
     As shown in  FIG.  178   , the projecting portion unit  903 B has a cylindrical shape, and includes a shaft portion  903 Ba, a first cylindrical portion  903 Bb having a diameter larger than that of the shaft portion  903 Ba, a second cylindrical portion  903 Bc having a diameter larger than that of the first cylindrical portion  903 Bb, and a cylindrical projecting portion  903 Bg (projecting portion, engaging portion) which are coaxial with the rotational axis A, in this order from the first end side in the first direction D 1 . That is, in this embodiment, the projecting portion  903 Bg is provided on the shutter unit  903  (shutter portion  903 A), not on the nozzle  902 . 
     The projecting portion  903 Bg has the same shape as the projecting portion  202   b  of Embodiment 2 described above, and therefore, the description thereof will be omitted. 
     An end surface  903 Bf and a two-way shaped two-sided cut portion  903 Be are provided on the first end side of the shaft portion  903 Ba on the first end side in the first direction D 1 . The second cylindrical portion  903 Bc is provided with an end surface  903 Bh perpendicular to the rotational axis A on the first end side in the first direction D 1 . 
     A hollow cylindrical shutter seal  922  is fitted on the outer periphery of the first cylindrical portion  903 Bb from the first end portion side of the first direction D 1 . The shutter seal  922  is made of an elastic sponge. The inner diameter of the shutter seal  922  is slightly smaller than the outer diameter of the first cylindrical portion  903 Bb, and therefore, the shutter seal  922  is mounted in close contact therewith, while expanding the inner diameter. Further, the shutter seal  922  is pushed toward the second end portion side in the first direction D 1  and is abutted against the end surface  903 Bh. 
     Here, as shown in  FIG.  177   , the first nozzle portion  902 A and the second nozzle portion  902 B are fixed by adhesive as described above. The shutter portion  903 A and the projecting portion unit  903 B are mounted, in the first direction D 1 , to the first nozzle portion  902 A and the second nozzle portion  902 B fixed to each other. 
     Specifically, the shaft portion  903 Ba of the projecting portion unit  903 B penetrates a through hole  902   m  (see  FIG.  182   ) of the second nozzle portion  902 B and the through hole  902 Ae of the first nozzle portion  902 A from the second end side in the first direction D 1 . Thereafter, the two-sided cut portion  903 Be of the projecting portion unit  903 B is fitted into the recess  903 Ae of the shutter portion  903 A, and the end surface  903 Bf abuts to the surface  903 Af (see  FIG.  182   ) and is fixed by adhesive. In addition, at this time, the shutter seal  922  mounted on the projecting portion unit  903 B is pushed into the first recess portion  902 Bg of the second nozzle portion  902 B from the second end side in the first direction D 1  (see  FIG.  182   ). Here, the outer diameter of the shutter seal  922  is slightly larger than the inner diameter of the first recess portion  902 Bg of the second nozzle portion  902 B, and the shutter seal  922  is closely mounted while being packed at the outer diameter portion. In addition, the shutter seal  922  is mounted so as to be abutted against the surface  902 Bn of the second nozzle portion  902 B and packed in the first direction D 1 . 
     Further, the opening seal  931  (see  FIG.  178   ) mounted to the shutter portion  903 A is compressed between in the first direction between the end surface  903 Ac of the shutter portion  903 A and the surface  902 Ak of the first nozzle portion  902 A (see  FIG.  179   ), and therefore is mounted without gap. 
     (Mounting Operation) 
     Next, referring to  FIGS.  180 ,  181  and  182   , the mounting to the image forming apparatus  1  will be described in the following. The operation of the mounting portion  206  in the mounting is the same as that of Embodiment 2, and therefore, the description thereof will be omitted. 
       FIG.  180    is a top view and a side view illustrating a state in which the toner pack  920  is mounted on the mounting portion  206 . Part (a) of  FIG.  180    and part (b) of  FIG.  180    are top views in a state in which the toner pack  920  is mounted and a state in which toner is replenished into the toner accommodating chamber  36  of the developer container  32 , respectively. Part (c) of  FIG.  180    and part (d) of  FIG.  180    are side views in a state in which the toner pack  920  is mounted and a state in which toner is replenished into the toner accommodating chamber  36  of the developer container  32 , respectively. 
       FIG.  181    and  FIG.  182    are cross-sectional views showing each cross-section along the sectional line shown in  FIG.  180   . 
     Part (a) of  FIG.  181   , part (b) of  FIG.  181   , part (c) of  FIG.  181   , and part (d) of  FIG.  181    are cross-sectional views taken along a line X 901 -X 901 , a cross-sectional view taken along a line X 903 -X 903 , a cross-sectional view taken along a line X 902 -X 902 , and a cross-sectional view taken along a line X 904 -X 904  in  FIG.  180   , respectively. Part (a) of  FIG.  182    and part (b) of  FIG.  182    are a sectional view taken along a line X 905 -X 905  and a sectional view taken along a line X 906 -X 906  in  FIG.  180   . 
     As shown in  FIG.  180   , the toner pack  920  is mounted on the mounting portion  206  in the same manner as in Embodiment 2. At this time, as shown in part (c) of  FIG.  181   , the discharge seal  933  mounted to the second nozzle portion  902 B is mounted while being packed by the cover  210  in the radial direction r of the imaginary circle VC. 
     At this time, as shown in part (a) of  FIG.  181   , the through hole  903 Ad of the shutter portion  903 A and the through hole  902 Ad of the first nozzle portion  902 A are placed at positions deviated from each other in the rotational direction about the rotational axis A. Here, as shown in part (a) of  FIG.  182   , an opening seal  931  is mounted to the second end side of the first direction D 1  of the through hole  903 Ad of the shutter portion  903 A, and the toner in the through hole  903 Ad prevented from leaking, by the shutter portion  903 A, an opening seal  931  and a first nozzle portion  902 A. 
     As shown in  FIG.  181   , after the toner pack  920  is mounted on the mounting portion  206 , the user rotates the operating lever  208  in the arrow D direction as in Embodiment 2. 
     At this time, the first nozzle portion  902 A and the second nozzle portion  902 B rotate integrally with each other with the operating lever  208  in the same manner as the pack side shutter  203  of Embodiment 2. This is because the recess  902 Bj of the second nozzle portion  902 B of the nozzle  902  engages with the drive transmission portion  208   a  of the operating lever  208  and the driven transmission portion  209   e  of the apparatus-side shutter  209 . 
     By the rotation of the first nozzle portion  902 A and the second nozzle portion  902 B, as shown in part (b) of  FIG.  181   , the through hole  903 Ad of the shutter portion  903 A and the through hole  902 Ad of the first nozzle portion  902 A become opposed. At this time, as shown in part (b) of  FIG.  182   , the toner of the toner pack  920  slides down the surface  903 Ah, passes through the through hole  903 Ad of the shutter portion  903 A, passes through the inside of the opening seal  931 , passes through the through hole  902 Ad of the first nozzle portion  902 A, and flows into the recess  902 Bd of the second nozzle portion  902 B. 
     At this time, as shown in part (b) of  FIG.  182   , an opening seal  931  is mounted to the second end side of the first direction D 1  of the through hole  903 Ad of the shutter portion  903 A so as to surround the through hole  902 Ad of the first nozzle portion  902 A. Therefore, the toner flowing in from the through hole  903 Ad of the shutter portion  903 A is prevented from leaking, by the opening seal  931  and does not flow out to other than the through hole  902 Ad. 
     Further, as shown in part (d) of  FIG.  181   , as the operating lever  208  rotates, the discharge seal  933  mounted to the second nozzle portion  902 B also rotates and moves in the arrow D direction together with the second nozzle portion  902 B, so that the discharge opening  902 Bk moves to a position facing the receiving opening  209   a  of the apparatus-side shutter  209 . At this time, the discharge seal  933  is in a state of being compressed to the receiving opening  209   a  in the radial direction r of the imaginary circle VC centered on the rotational axis A. Therefore, the discharge seal  933  seals between the discharge opening  902 Bk of the second nozzle portion  902 B and the receiving opening  209   a  of the apparatus-side shutter  209 , and the toner is prevented from leaking thereby. 
     Further, as shown in part (d) of  FIG.  182   , even when toner flows through the slight gap between the through hole  902   m  of the second nozzle portion  902 B and the shaft portion  903 Ba of the projecting portion unit  903 B along the shaft portion  903 Ba toward the second end portion side, the toner does not flow out to the outside of  920  in the first direction D 1 , because the shutter seal  922  seals between the second nozzle portion  902 B and the projecting portion unit  903 B in a compressed state. 
     Thus, the toner in the accommodating portion  901  is replenished into the toner accommodating chamber  36  of the developer container  32  through the discharge opening  902 Bk of the second nozzle portion  902 B as in Embodiment 2. 
     In addition, after the toner replenishment is finished, the operating lever  208  is rotated in the direction of arrow E in the same manner as in Embodiment 2, by which the toner pack  920  becomes able to be removed from the main assembly of the apparatus, but it is the same as that described above, and therefore, the description thereof will be omitted. 
     As described foregoing, in the toner pack  920  of this embodiment, the projection  903 Bg is provided on the shutter unit  903  which is structured to be rotatable relative to the nozzle  902 . 
     In this embodiment, the opening seal  931  seals between the shutter portion  903 A and the first nozzle portion  902 A, but as described above, it is also possible to employ a structure in which the toner seal provided at the nozzle opening is broken or pulled out. 
     Further, in this embodiment, since the toner pack  920  does not seal the discharge opening  902 Bk after finishing the toner replenishment, it is conceivable that the deposited toner may flow out from the discharge opening  902 Bk. 
     Therefore, an adhesive seal (not shown) which closes the discharge opening  902 Bk after use by the user may be mounted. 
     Embodiment 10 
     Next, referring to  FIGS.  183  to  191   , another structure will be described. The same points as those of the above-described embodiments and modified examples will be omitted. In particular, of the elements disclosed in this embodiment, those corresponding to the above-mentioned members will be assigned the same names as the above-mentioned members, and only the points different from the above-mentioned members will be described. 
     In the structure shown in Embodiment 2, the projecting portion  202   b  is provided at the nozzle  202 , but it is also possible to provide the projection on the rotatable member which is rotatable relative to the accommodating portion  201  and the nozzle  202 . Hereinafter, a structure in which a projecting portion is provided on the rotatable member will be described. 
     Referring to  FIGS.  183 ,  184 ,  185 , and  186   , the structure of the toner pack  10020  will be described.  FIG.  183    is a perspective view of a toner pack  10020  of this embodiment.  FIG.  184    is an exploded perspective view of the toner pack  10020 .  FIG.  185    is exploded views of the nozzle of this embodiment, in which part (a) of  FIG.  185    and part (b) of  FIG.  185    are exploded perspective views as seen in different directions, part (c) of  FIG.  185    is a side view, and part (d) of  FIG.  185    is a sectional view taken along a line X 1001 -X 1001  in part (c) of  FIG.  185   .  FIG.  186    is an exploded perspective view of the pack-side shutter in this embodiment, and part (a) of  FIG.  186    and part (b) of  FIG.  186    are exploded perspective views as seen in different directions. 
     As shown in  FIG.  184   , the toner pack  10020  includes an accommodating portion  201  (first accommodating portion), a first nozzle portion  1002 A, a second nozzle portion  1002 B, a shutter  1003  and a screw  1030 , in this order from the side of the first end portion in the first direction D 1 . 
     As shown in  FIG.  185   , the first nozzle portion  1002 A has a cylindrical shape coaxial with the rotational axis A (central axis), and includes a first cylindrical portion  1002 Aa a disk portion  1002 Ab having a diameter larger than that of the first cylindrical portion  1002 Aa, a second cylindrical portion  1002 Ad having a diameter smaller than that of the disk portion  1002 Ab (see part (d) of  FIG.  185   ), in this order from the first end portion side in the first direction D 1 . Inside the second cylindrical portion  1002 Ad, a through hole  1002 Af coaxial with the rotational axis A is provided. 
     The disk portion  1002 Ab is provided with a third cylindrical portion  1002 Ac which projects toward the second end portion in the first direction D 1  and has a diameter larger than that of the second cylindrical portion  1002 Ad, coaxially with the rotational axis A. The third cylindrical portion  1002 Ac projects beyond the second cylindrical portion  1002 Ad toward the second end portion in the first direction D 1 . 
     In addition, the disk portion  1002 Ab is provided with a fourth cylindrical portion  1002 Ag, which projects toward the second end portion in the first direction D 1  and has a diameter larger than that of the third cylindrical portion  1002 Ac, coaxially with the rotational axis A. 
     A D-cut portion  1002 Ak is provided on the first end portion side in the first direction D 1  inside the third cylindrical portion  1002 Ac. Inside the first cylindrical portion  1002 Aa, a slope  1002 Ah inclined toward the through hole  1002 Af is provided so as to approach the rotational axis A toward the second end portion side in the first direction D 1 . In the first nozzle portion  1002 A, the first cylindrical portion  1002 Aa is integrally coupled with the accommodating portion  201  (see  FIG.  184   ). 
     As shown in part (a) of  FIG.  185    and part (b) of  FIG.  185   , in the second nozzle portion  1002 B, the outer cylindrical portion  1002 Ba and the inner cylindrical portion  1002 Bb coaxial with the rotational axis A are connected at an end surface  1002 Bc placed on the second end portion side in the first direction D 1 . The inner cylindrical portion  1002 Bb has a cylindrical shape, and as shown in part (d) of  FIG.  185   , It is provided with a partition plate  1002 Bn so as to partition the inside of the cylindrical portion perpendicular to the rotational axis A. Here, a cylindrical recess on the first end portion side in the first direction D 1  partitioned by the partition plate  1002 Bn is referred to as a recess  1002 Bf, and a cylindrical recess on the second end portion is referred to as a recess  1002 Bg. The outer peripheral surface  1002 Bd of the inner cylindrical portion  1002 Bb is provided with a discharge opening  1002 Be (opening) which communicates with the recess  1002 Bf. On the second end portals the of the partition plate  1002 Bn in the first direction D 1 , a screw hole portion  1002 Bh recessed toward the first end portion side in the first direction D 1  is provided coaxially with the rotational axis A. A D-cut portion  1002 Bk and an end surface  1002 Bm are provided on the outer diameter portion on the first end portion side of the inner cylindrical portion  1002 Bb in the first direction D 1 . On the outer surface of the outer cylindrical portion  1002 Ba, a recess  1002 Bj recessed inside in the radial direction r of the imaginary circle VC is provided. The recess  1002 Bj is structured to engage the drive transmission portion  208   a  of the operating lever  208  and the driven transmission portion  209   e  of the apparatus-side shutter  209  when the toner pack  10020  is mounted to the mounting portion  206 . 
     The D-cut portion  1002 Bk of the second nozzle portion  1002 B is fitted into the D-cut portion  1002 Ak of the first nozzle portion  1002 A from the second end portion side in the first direction D 1 . Then, in a state that the end surface  1002 Bm abuts on the disk portion  1002 Ab, the second nozzle portion  1002 B is integrally bonded to the first nozzle portion  1002 A by adhesive or the like. 
     As shown in part (a) of  FIG.  186   , the shutter  1003  has a cylindrical shape and includes, a cylindrical portion  1003   a  and a projecting portion  1003   b  (projection portion, engagement) in this order from the first end portion side in the first direction D 1 , coaxially with the rotational axis A. The projecting portion  1003   b  has the same shape as the projecting portion  202   b  of Embodiment 2, and therefore, the description thereof will be omitted. A through hole  1003   c  is provided coaxially with the rotational axis A in the cylindrical portion  1003   a . A semi-cylindrical shutter portion  1003   d  (rotatable member) is provided coaxially with the rotational axis A on the outside of the cylindrical portion  1003   a . The shutter portion  1003   d  of the shutter  1003  is rotatable relative to the second nozzle portion  1002 B between an open position for opening the discharge opening  1002 Be (opening) provided in the outer peripheral surface  1002 Bd of the second nozzle portion  1002 B and a shielding position for shielding the discharge opening  1002 Be (opening). As shown in part (b) of  FIG.  186   , the shutter portion  1003   d  and the cylindrical portion  1003   a  are connected by an end surface  1003   e  placed on the second end portion side of the shutter portion  1003   d  in the first direction D 1 . The shutter portion  1003   d  is provided with a through hole  1003   f  which penetrates in the radial direction r of the imaginary circle VC centered on the rotational axis A. 
     The first discharge seal  1031  is mounted to the shutter portion  1003   d  of the shutter  1003  from the opposite side in the radial direction r. The first discharge seal  1031  has a flat plate shape having a through hole  1031   a , and is formed of an elastic sponge or the like. The first discharge seal  1031  is mounted on the shutter  1003  by adhesive or the like so that the through hole  1031   a  surrounds the through hole  1003   f  on the outer peripheral surface side of the shutter portion  1003   d.    
     In addition, a second discharge seal  1032  is mounted to the shutter portion  1003   d  from the side in the radial direction r. The second discharge seal  1032  has a flat plate shape including a through hole  1032   a , and is formed of an elastic sponge or the like. The second discharge seal  1032  is mounted to the shutter  1003  on the inner peripheral surface side of the shutter portion  1003   d  by adhesive or the like so that the through hole  1032   a  surrounds the through hole  1003   f . Further, as shown in part (b) of  FIG.  186   , two projections  1003   m  and  1003   n  projecting toward the radial direction r are provided on the second end portion side of the first direction D 1  of the shutter portion  1003   d.    
     Next, referring to  FIG.  187   , the mounting of the shutter  1003  will be described. Part (a) of  FIG.  187    is a side view of the toner pack  10020 , and part (b) of  FIG.  187    is a sectional view taken along a line X 1002 -X 1002  in part (a) of  FIG.  187   . 
     As shown in part (b) of  FIG.  187   , the shutter  1003  is coaxially mounted to the second nozzle portion  1002 B from the second end portion side in the first direction D 1  along the rotational axis A. At this time, the cylindrical portion  1003   a  of the shutter  1003  is inserted into the recess  1002 Bg of the second nozzle portion  1002 B. The shutter  1003  is inserted until the end surface  1003   h  on the side of the first end portion of the cylindrical portion  1003   a  in the first direction D 1  abuts to the partition plate  1002 Bn of the second nozzle portion  1002 B. At the same time, the shutter  1003  is mounted to the second nozzle portion  1002 B while packing the first discharge seal  1031  between the outer cylindrical portion  1002 Ba of the second nozzle portion  1002 B and the shutter portion  1003   d  of the shutter  1003 . Similarly, the shutter  1003  is mounted to the second nozzle portion  1002 B while packing the second discharge seal  1032  between the shutter portion  1003   d  of the shutter  1003  and the inner cylindrical portion  1002 Bb of the second nozzle portion  1002 B. 
     Thereafter, in the shutter  1003 , the first end portion side of the shutter portion  1003   d  in the first direction D 1  is fitted between the third cylindrical portion  1002 Ac and the fourth cylindrical portion  1002 Ag of the first nozzle portion  1002 A. In this manner, the cylindrical portion  1003   a  engages with the recess  1002 Bg, and the shutter portion  1003   d  engages with the third cylindrical portion  1002 Ac and the fourth cylindrical portion  1002 Ag, so that the shutter  1003  is supported so as to be rotatable about the rotational axis A relative to the second nozzle portion  1002 B. That is, the shutter  1003  is a rotatable member which is rotatable about the rotational axis A relative to the first nozzle portion  1002 A and the second nozzle portion  1002 B, which are discharge portions. 
     Next, on the shutter  1003 , a screw  1030  is threaded coaxially with the rotational axis A from the second end portion side in the first direction D 1 . As shown in part (b) of  FIG.  187   , the screw  1030  includes, the threaded portion  1030   b  and a disk portion  1030   a  having a diameter larger than that of the threaded portion  1030   b  coaxially with the rotational axis A, in this order from the first end portion side in the first direction D 1 . The screw  1030  penetrates the through hole  1003   f  of the shutter  1003  and is screwed into the screw hole portion  1002 Bh of the second nozzle portion  1002 B. The outer diameter of the threaded portion  1030   b  of the screw  1030  is smaller than the through hole  1003   f  of the shutter  1003  and does not come into contact with each other. In this manner, the shutter  1003  is supported so as to be sandwiched between the partition plate  1002 Bn of the second nozzle portion  1002 B and the disk portion  1030   a  of the screw  1030 . 
     At this time, in the direction of the rotational axis A, the shutter  1003  is supported with a slight gap between the second nozzle portion  1002 B and the screw  1030 . In this manner, the shutter  1003  is supported so as to be rotatable relative to the second nozzle portion  1002 B about the rotational axis A against the friction produced by the first discharge seal  1031  and the second discharge seal  1032 . 
     With the above-described structure, as shown in part (b) of  FIG.  187   , the toner of the accommodating portion  201  slides down the slope  1002 Ah of the first nozzle portion  1002 A and flows into the recess  1002 Bf by way of the through hole  1002 Af. The discharge opening  1002 Be leading to the recess  1002 Bf is sealed by the second discharge seal  1032  mounted in the shutter portion  1003   d  of the shutter  1003 . This is the case where the shutter  1003  is in the shielded position relative to the second nozzle portion  1002 B. 
     Next, referring to  FIGS.  188  to  191   , mounting the toner pack  10020  on the image forming apparatus  1  will be described.  FIGS.  188  and  189    are illustrations of a state in which the toner pack  10020  is mounted on the mounting portion  206 . Part (a) of  FIG.  188    is a top view, part (b) of  FIG.  188    is a side view, part (c) of  FIG.  188   , parts (a) and (b) of  FIG.  189    are sectional views taken along lines X 1003 -X 1003 , X 1004 -X 1004  and X 1005 -X 1005  in part (b) of  FIG.  188   , respectively.  FIGS.  190  and  191    are illustrations of a state in which the toner of the toner pack  10020  is being supplied into the toner accommodating chamber  36  of the developer container  32 . Part (a) of  FIG.  190    is a top view, part (b) of  FIG.  190    is a side view, and part (c) of  FIG.  190    and  FIG.  191    are sectional and cross-sectional views taken along lines X 1006 -X 1006  and X 1007 -X 1007  in part (b) of  FIG.  190   , respectively. 
     As shown in part (a) of  FIG.  188    and part (a) of  FIG.  190   , the toner pack  10020  is mounted on the mounting portion  206  in the same manner as in Embodiment 2. At this time, as shown in part (b) of  FIG.  189   , the projections  1003   m  and  1003   n  of the shutter  1003  are mounted so as to sandwich the cover  210  on the apparatus-side in the rotational direction about the center of the rotational axis A. In this manner, the shutter  1003  is positioned relative to the mounting portion  206  in the rotational direction about the rotational axis A. 
     In addition, as shown in part (a) of  FIG.  189   , the discharge opening  1002 Be of the second nozzle portion  1002 B is sealed with the second discharge seal  1032  mounted on the shutter portion  1003   d  of the shutter  1003  as described above. 
     Next, as shown in part (a) of  FIG.  190   , when the user rotates the operating lever  208  in the rotational direction D the apparatus side shutter  209 , the nozzle portion  1002 B, the first nozzle portion  1002 A, and the accommodating portion  201  rotate integrally with the operating lever  208  (see part (a) of  FIG.  190   ), as shown in part (c) of  FIG.  190    and  FIG.  191   . At this time, as described above, the shutter  1003  does not rotate relative to the mounting portion  206  because the shutter  1003  is positioned with respect to the cover  210  (see part (b) of  FIG.  189   ) in the rotational direction centered on the rotational axis A. Even when the accommodating portion  201  is formed of a bag or the like, the second nozzle portion  1002 B, the first nozzle portion  1002 A, and the accommodating portion  201  are integrally rotated by rotating the operating lever  208 , according to this embodiment, and therefore, it is easy to operate. 
     Therefore, as shown in  FIG.  191   , the second nozzle portion  1002 B rotates relative to the shutter  1003  which does not move and rotate in the rotational direction D, and the discharge opening  1002 Be becomes opposed to the through hole  1003   f  of the shutter  1003  in the radial direction r of the imaginary circle VC centered on the rotational axis A. This position is when the shutter  1003  is in the open position for the second nozzle portion  1002 B. 
     At this time, between the second nozzle portion  1002 B and the shutter  1003 , and the second discharge seal  1032  surrounding the discharge opening  1002 Be and the through hole  1003   f  is in the state of being compressed in the radial direction r and they are in close contact with each other. Similarly, the apparatus-side shutter  209  also rotates relative to the shutter  1003  in the rotational direction D, and the receiving opening  209   a  is placed to oppose the through hole  1003   f  of the shutter  1003  in the radial direction r. At this time, between the apparatus-side shutter  209  and the shutter  1003 , are surrounded, and the first discharge seal  1031  surrounding the receiving opening  209   a  and the through hole  1003   f  is in a state of being compressed in the radial direction r and they are in close contact with each other. 
     Therefore, the toner discharged from the discharge opening  1002 Be of the second nozzle portion  1002 B is discharged to the receiving opening  209   a  of the apparatus-side shutter  209  through the through hole  1003   f  of the shutter  1003 . 
     Thus, the toner in the accommodating portion  201  is replenished into the toner accommodating chamber  36  in the developer container  32  through the first nozzle portion  1002 A, the second nozzle portion  1002 B, the shutter  1003 , and the apparatus-side shutter  209 . 
     Further, after the toner is replenished, the operating lever  208  can be rotated in the direction of arrow E as in Embodiment 2, and the toner pack  10020  can be removed from the main assembly of the apparatus, and it is only the reverse of the above-described operations, and therefore, the description thereof is omitted. 
     Embodiment 11 
     Next, referring to  FIGS.  192  to  195   , the structure of the toner pack  1120  of this embodiment will be described. The same points as those of the above-described embodiments and modified examples will be omitted. In particular, of the elements disclosed in this embodiment, those corresponding to the members of Embodiment 2 will be assigned the same names as the members of Embodiment 2, and only the points different from the above-mentioned points will be described. 
     In the structure shown in Embodiment 2, the nozzle  202  of the toner pack  220  is integrally provided with the projecting portion  202   b , but by making the nozzle as a movable separate portion, the toner pack  220  can be downsized. The structure in which the nozzle is provided as a movable separate component will be described in the following. 
       FIG.  192    is a perspective view illustrating a state in which a free end member  1132  of the toner pack  1120  of this embodiment is in a second attitude.  FIG.  193    is a partially exploded perspective view of the toner pack  1120  according to this embodiment. In this embodiment, the toner pack  1120  has the same structure as that of Embodiment 2 except for the projecting portion of the nozzle and the shutter on the pack side. In this embodiment, as shown in  FIG.  193   , the projecting member  1130  is mounted to the nozzle  1102  from the second end side in the first direction D 1 . 
     Referring to  FIGS.  193  and  194   , the structure of the projecting member  1130  will be described.  FIG.  194    is an exploded perspective view of the projecting member  1130  of this embodiment, and part (a) of  FIG.  194    and part (b) of  FIG.  194    are exploded perspective views as seen from different directions. 
     As shown in part (a) of  FIG.  194   , the projecting member  1130  comprises a fixed shaft  1131  and a free end member  1132 , in this order from the first end side in the first direction D 1 . The structure is such that the free end member  1132  is movable between a second attitude in which the axis of a cylindrical portion  1132   a  intersects the rotational axis A (central axis) and a first attitude in which the axis of the cylindrical portion  1132   a  is substantially aligned with the rotational axis A. Details will be described hereinafter. 
     The fixed shaft  1131  has a shaft shape and is coaxial with the rotational axis A. The fixed shaft  1131  is provided with an end surface  1131   a  on the first end side in the first direction D 1 , and a shaft portion  1131   b  having a double sided flat shape. In addition, the fixed shaft  1131  is provided with a through hole  1131   c  perpendicular to the rotational axis A. A curved end surface  1131   d  coaxial with the through hole  1131   c  is provided on the second end side of the fixed shaft  1131  in the first direction D 1 . Further, a slit portion  1131   e  is provided on the second end side of the fixed shaft  1131  in the first direction D 1  in parallel with the rotational axis A and perpendicular to the axis direction of the through hole  1131   c . The end surface  1131   d  is provided with a plurality of projections ( 1131   f ,  1131   g ,  1131   h ) projecting in a direction away from the axis of the through hole  1131   c . Here, the plurality of projections are symmetrically provided with the slit portion  1131   e  interposed therebetween, and therefore, The description will be made as to only one side thereof. The end surface  1131   d  is provided with a projection  1131   f  projecting in a direction away from the axis of the through hole  1131   c  and in a direction perpendicular to the rotational axis A. Further, the end surface  1131   d  is provided with projections  1131   g  and  1131   h  projecting in the direction away from the axis of the through hole  1131   c  and in the direction of the rotational axis A at intervals from each other. 
     The free end member  1132  has a cylindrical shape, and is provided in the direction perpendicular to the rotational axis A and the axial direction of the through hole  1131   c  of the fixed shaft  1131 . 
     The free end member  1132  is provided so that the cylindrical portion  1132   a  and the projecting portion  1132   b  projecting from the cylindrical portion  1132   a  are coaxial with each other in the radial direction r of the imaginary circle VC centered on the rotational axis A. Here, the projecting portion  1132   b  has the same shape as the projecting portion  202   b  of the nozzle  202  of Embodiment 2, and therefore, the description thereof will be omitted. 
     From the cylindrical portion  1132   a , a support plate portion  1132   c  (support portion) projecting in the axial direction of the cylindrical portion  1132   a  is provided. The support plate portion  1132   c  has a flat plate shape symmetric with respect to the axis of the cylindrical portion  1132   a , and is provided in a direction perpendicular to the axis direction of the through hole  1131   c . The support plate portion  1132   c  is provided with a through hole  1132   d  and a spherical projection  1132   e  in the radial direction r of the imaginary circle VC centered on the rotational axis A. The spherical projections  1132   e  are provided symmetrically at two positions with the support plate portion  1132   c  interposed therebetween. 
     As shown in  FIG.  194   , the support plate portion  1132   c  of the free end member  1132  is inserted into the slit portion  1131   e  of the fixed shaft  1131  in the direction perpendicular to the rotational axis A and the through hole  1131   c  (direction of arrow  11 B). Further, a parallel pin  1133 , which is a rod-shaped member, is coaxially inserted into the through hole  1132   d  of the support plate portion  1132   c  and the through hole  1131   c  of the fixed shaft  1131 . 
     In this manner, the free end member  1132  is supported so as to be rotatable relative to the fixed shaft  1131  by way of the parallel pin  1133 . In addition, at this time, the projection  1132   e  mounted on the support plate portion  1132   c  of the free end member  1132  is in contact with the projection  1131   f  of the fixed shaft  1131  and is constrained from rotating in the rotational direction  11 A centered on the through hole  1131   c  (see part (b) of  FIG.  195   ). 
     As shown in  FIG.  193   , in the fixed shaft  1131 , the shaft portion  1131   b  is inserted into the hole  1102   a  which has the double sided flat in the rotational axis direction A and which is provided in the nozzle  1102  of the toner pack  1120 , from the second end side of the first direction D 1 , until abutting to the end surface  1131   a , and then it is fixed by adhesive or the like. 
     Next, referring to  FIG.  195   , the user&#39;s operation before use will be described. 
       FIG.  195    is a side view and a sectional view illustrating a user operation of the projecting member  1130 . 
     Part (a) of  FIG.  195    is a side view illustrating the projecting member  1130 . Part (b) of  FIG.  195    is a sectional view taken along a line X 1101 -X 1101  in part (a) of  FIG.  195   , showing a state in which the free end member  1132  is in the second attitude. Part (c) of  FIG.  195    shows a state in which the free end member  1132  has moved to the first attitude from the position of part (b) of  FIG.  195   . 
     As shown in part (b) of  FIG.  195   , before the user operation, the free end member  1132  (and the cylindrical portion  1132   a ) of the projecting member  1130  is provided on the fixed shaft  1131  so as to cross the rotational axis A. 
     At this time, as described above, the projection  1132   e  of the free end member  1132  contacts the projection  1131   f  of the fixed shaft  1131  in the rotational direction  11 A centered on the through hole  1131   c , so that the rotation in the rotational direction of the rotational direction  11 A is restricted. 
     Next, the user rotates the free end member  1132  in the rotational direction  11 A relative to the fixed shaft  1131 . The projection  1132   e  of the free end member  1132  rides on the projection  1131   f  and rotates in the rotational direction  11 A while expanding between the two projections  1131   f  away from each other (through hole  1131   c  axial direction). The user further rotates the free end member  1132 , and the projection  1132   e  rides on the projection  1131   g  while expanding between the two projections  1131   g  in the direction away from each other (through hole  1131   c  axial direction) in the same manner as the projection  1131   f , until the projection  1132   e  abuts against the projection  1131   h , by which the rotation in the rotational direction  11 A stops. At this time, the projection  1132   e  of the free end member  1132  is sandwiched between the projection  1131   g  and the projection  1131   h  of the fixed shaft  1131  in the rotational direction about the through hole  1131   c , so that the free end member  1132  is fixedly supported coaxially with the rotational axis A. 
     Thereafter, the toner pack  1120  is mounted to the image forming apparatus  1 . 
     In this modified example, the nozzle  202  of Embodiment 2 has the same structure as that of Embodiment 2 except that the nozzle  202  is replaced with the nozzle  1102  and the projecting member  1130 , and other description thereof will be omitted. 
     As described in the foregoing, by making the free end member  1132  movable between the second attitude and the second attitude, and by making it possible to transport the toner pack  1129  the second attitude, the packing size of the toner pack  1120  can be reduced in the direction of the rotational axis A. When the toner pack  1120  is used, the user shifts the free end member  1132  to the first attitude, so that the rotation restricting mechanism  212  of the apparatus-side shutter  209  can be released with the mounting of the toner pack  1120  as in other embodiments. 
     Further, in this embodiment, the structure in which the free end member  1132  is one component has been described, but by employing the engaging means divided into two or more portions as separate movable portions, the outer shape is reduce, with the similar advantageous effect. 
     The structures of Embodiments 1 to 11 and the modified examples of each embodiment may be usable with combination with each other. 
     Finally, the typical structures disclosed in the present application are summarized in the following. The following, the elements may be accompanied by reference numerals and or characters signed to indicate the correspondence with the above-described embodiments. However, this correspondence is just an example for reference, and the elements in the following structure are not limited to the corresponding elements with the reference numerals and or characters in the above-described embodiments. 
     Structure Example A1 
     A toner container ( 100 ,  1050 ,  1051 ,  1052 ,  1060 ,  1070 ,  1080 ,  220 ,  2320 ,  23210 ,  2420 ,  2520 ,  2530 ,  520 ,  5120 ,  920 ,  10020 , and  1120 ) comprising: 
     an accommodating portion ( 101 ,  1015 ,  10151 ,  201 ,  2401 ,  501 ,  901 ) configured to accommodate toner; 
     a discharge portion ( 102 ,  1025 ,  202 ,  2302 ,  23102 ,  2402 A,  2502 ,  2503 ,  502 ,  5102 ,  902 ,  1002 A,  1102 ) configured to be provided with an opening ( 102   a ,  202   a ,  2402 Ag,  2502   k   2 ,  2503   k   2 ,  502   a ,  902 Bk,  10020 Be) for discharging the toner in the accommodating portion to an outside; 
     a rotatable member ( 103 ,  203 ,  903 A,  1003 ) rotatable about a central axis (A) as a rotational axis relative to the discharge portion in a first rotational direction (K, D) and a second rotational direction (L, E) opposite to the first rotational direction; and 
     a projection ( 102   b ,  1020   b ,  1021   b ,  1023   b ,  1024   b ,  1026   b ,  1027   b ,  1028   b ,  202   b ,  2302   b ,  23102   b ,  2402 Bb,  2502   b ,  2503   b ,  502   b ,  5102   b ,  903 Bg,  1003   b ,  1132   b ) provided below the opening of the discharge portion and having an inner peripheral surface facing inward in a radial direction (r) of an imaginary circle (VC) centered on the central axis, when the toner container is oriented in a predetermined direction in which the central axis extends in a direction of gravity and at least a part of the discharge portion is below the accommodating portion; 
     wherein the opening of the discharge portion is configured to face outward in the radial direction, and 
     wherein when the toner container is oriented in the predetermined direction, 
     the projection has an upward surface ( 104   a   2 ,  104   b   2 ,  1041   a   2 ,  1042   b   2 ,  1043   a   2 ,  1043   b   2 ,  1044   a   2 ,  1046   a   2 ,  1047   a   2 ,  1048   a   2 ,  204   a   3 ,  204   b   3 ,  2304   a   2 ,  2304   b   2 ,  23104   a   2 ,  23104   b   2 ,  2604   a   3 ) facing upward outside the inner peripheral surface and inside the opening of the discharge portion in the radial direction, and 
     the upward surface extends so as to go up as goes in the second rotating direction. 
     Structure Example A2 
     A toner container according to Structure Example A1, wherein the upward surface is configured to be exposed to an outside of the toner container. 
     Structure Example A3 
     A toner container according to Structure Example A1 or A2, wherein when the toner container is oriented in the predetermined direction, a cavity is provided above the upward surface of the projection. 
     Structure Example A4 
     A toner container according to any one of Structure Examples A1-A3, wherein the projection has a downstream side end surface which extends upward along the central axis from a downstream end of the upward surface in the second rotational direction and which faces a downstream side in the first rotational direction, when the toner container is oriented in the predetermined direction. 
     Structure Example A5 
     A toner container according to any one of Structure Examples A1-A4, wherein the upward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees as the toner container is viewed in the radial direction in the state in which the toner container is oriented in the predetermined direction. 
     Structure Example A6 
     A toner container according to any one of Structure Examples A1-A5, wherein as the discharge portion is viewed in the direction of the central axis, the upward surface is provided closer to inner peripheral surface than to the opening, in the radial direction. 
     Structure Example A7 
     A toner container according to Structure Example A6, wherein as the discharge portion is viewed in the direction of the central axis, a distance from the inner peripheral surface to the upward surface is not more than 30% a distance from the inner peripheral surface to the opening. 
     Structure Example A8 
     A toner container according to any one of Structure Examples A1-A7, wherein when the toner container is oriented in the predetermined direction, the projection has a downward surface facing downward extending so as to go up as goes in the first rotational direction, and at least a part of the upward surface being above at least a part of the downward surface. 
     Structure Example A9 
     A toner container according to Structure Example A8, wherein the downward surface overlaps the upward surface, as viewed in the direction of the central axis. 
     Structure Example A10 
     A toner container according to Structure Example A8 or A9, wherein the projection has a connecting portion connecting a downstream end of the downward surface in the first rotational direction and an upstream end of the upward surface in the second rotational direction with each other. 
     Structure Example A11 
     A toner container according to any one of Structure Examples A8-A10, wherein the downward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A12 
     A toner container according to any one of Structure Examples A8-A11, wherein the upward surface is longer than the downward surface, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A13 
     A toner container according to any one of Structure Examples A8-A12, wherein the projection includes a first projection and a second projection which is provided at a position different from a position at which the first portion is provided in a circumferential direction of the imaginary circle, 
     wherein the upward surface and the downward surface are first upward surface and second downward surface, respectively, 
     the first projection includes the first upward surface and the second downward surface, and 
     the second projection includes a second upward surface and a fourth downward surface. 
     Structure Example A14 
     A toner container according to Structure Example A13, wherein the second upward surface and the fourth downward surface have 150-210 degree inclusive rotational symmetry shapes of the first upward surface and the second downward surface, respectively. 
     Structure Example A15 
     A toner container according to Structure Example A14, wherein the second upward surface and the fourth downward surface have 180 degree rotational symmetry shapes of the first upward surface and the second downward surface, respectively. 
     Structure Example A16 
     A toner container according to any one of Structure Examples A8-A12, wherein the projection includes a first projection and a second projection which is provided at a position different from a position at which the first projection is provided in a circumferential direction of the imaginary circle, the first projection includes the upward surface, and the second projection includes the downward surface. 
     Structure Example A17 
     A toner container according to Structure Example A16, wherein the second projection is provided at a position diametrically opposite to the first projection. 
     Structure Example A18 
     A toner container ( 220 ,  2420 ,  2520 ,  2530 ,  320 ,  520 ,  5120 ,  620 ,  820 ,  920 ,  10020 ,  1120 ) comprising: 
     an accommodating portion ( 201 ,  2401 ,  501 ,  901 ) configured to accommodate toner; 
     a discharge portion ( 202 ,  2402 A,  2502 ,  2503 ,  302 ,  502 ,  5102 ,  902 ,  1002 A,  1102 ) configured to be provided with an opening ( 202   a ,  2402 Ag,  2502   k   2 ,  2503   k   2 ,  302   a ,  502   a ,  902 Bk,  10020 Be) for discharging the toner in the accommodating portion to an outside; 
     a rotatable member ( 203 ,  903 A,  1003 ) rotatable about a central axis (A) as a rotational axis relative to the discharge portion in a first rotational direction (K, D) and a second rotational direction (L, E) opposite to the first rotational direction; and 
     a projection ( 202   b ,  2402 Bb,  2502   b ,  2503   b ,  304 ,  3104 ,  502   b ,  5102   b ,  604 ,  804 ,  8104 ,  8204 ,  8304 ,  903 Bg,  1003   b ,  1132   b ) provided below the opening of the discharge portion and having an inner peripheral surface ( 202   b   1 ,  202   b   10 ,  804   a   11 ) facing inward in a radial direction of an imaginary circle centered on the central axis, when the toner container is oriented in a predetermined direction in which the central axis extends in a direction of gravity and at least a part of the discharge portion is below the accommodating portion, wherein the opening of the discharge portion faces in the radial direction, 
     wherein when the toner container is oriented in the predetermined direction, 
     the projection has a first downward surface ( 204   a   1 ,  304   a   1 ,  604 Aa 1 ,  804   a   1 ,  204   b   1 ,  304   b   1 ,  604 Ab 1 ,  804   b   1 ) and a second downward surface ( 204   a   2 ,  304   a   2 ,  604 Ba 1 ,  804   a   2 ,  204   b   2 ,  304   b   2 ,  604 Bb 1 ,  804   b   2 ) which face downward, and an upward surface ( 204   a   3 ,  204   b   3 ,  2604   a   3 ,  304   a   3 ,  304   b   3 ,  3104   a   3 ,  3104   b   3 ,  604 Ba 2 ,  604 Bb 2 ,  804   a   3 ) which faces upward, outside the inner peripheral surface and inside the opening of the discharge portion in the radial direction, 
     the first downward surface and the second downward surface extend so as to go up as goes in the first rotational direction, and at least a part of the first downward surface is provided at a position which is closer to the central axis in the radial direction than the second downward surface is and which is different from a position at which the second downward surface is provided in a circumferential direction of the imaginary circle, and 
     at least a part of the upward surface is above at least a part of the second downward surface. 
     Structure Example A19 
     A toner container according to Structure Example A18, wherein when the toner container is oriented in the predetermined direction, the upward surface extends so as to go up as goes in the second rotational direction. 
     Structure Example A20 
     A toner container according to Structure Example A19, wherein the upward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A21 
     A toner container according to Structure Example A18, wherein the upward surface is a surface perpendicular to the central axis. 
     Structure Example A22 
     A toner container according to Structure Example A18, wherein when the toner container is oriented in the predetermined direction, the upward surface extends so as to go on as goes in the first rotational direction. 
     Structure Example A23 
     A toner container according to any one of Structure Examples A18-A22, wherein the upward surface is configured to be exposed to an outside of the toner container. 
     Structure Example A24 
     A toner container according to any one of Structure Examples A18-A23, wherein a cavity is provided above the upward surface of the projection, when the toner container is oriented in the predetermined direction. 
     Structure Example A25 
     A toner container according to any one of Structure Examples A18-A24, wherein the projection has a downstream side end surface which extends upward along the central axis from a downstream end of the upward surface in the second rotational direction and which faces a downstream side in the first rotational direction, when the toner container is oriented in the predetermined direction. 
     Structure Example A26 
     A toner container according to any one of Structure Examples A18-A25, wherein the second downward surface overlaps the upward surface as viewed in the direction of the central axis. 
     Structure Example A27 
     A toner container according to any one of Structure Examples A18-A26, wherein the projection has a connecting portion connecting a downstream end of the second downward surface in the first rotational direction and an upstream end of the upward surface in the second rotational direction with each other. 
     Structure Example A28 
     A toner container according to any one of Structure Examples A18-A27, wherein upward surface and the second downward surface are provided at positions closer to the inner peripheral surface than to the opening in the radial direction. 
     Structure Example A29 
     A toner container according to Structure Example A28, wherein a distance from the inner peripheral surface to the upward surface and a distance from the inner peripheral surface to the second downward surface are not more than 30% a distance from the inner peripheral surface to the opening. 
     Structure Example A30 
     A toner container according to any one of Structure Examples A18-A29, wherein the second downward surface is movable relative to the first downward surface between an alignment position in which the second downward surface is aligned with the first downward surface in the circumferential direction, and a non-alignment position in which it is not aligned with the first downward surface in the circumferential direction. 
     Structure Example A31 
     A toner container according to any one of Structure Examples A18-A29, wherein the second downward surface is movable relative to the first downward surface between an alignment position in which the second downward surface is aligned with the first downward surface in the radial direction and a non-alignment position in which it is not aligned with the first downward surface in the radial direction. 
     Structure Example A32 
     A toner container according to any one of Structure Examples A18-A31, wherein the projection includes a first projection and a second projection which is provided at a position different from a position at which the first projection is provided in the circumferential direction, 
     wherein the upward surface is a first upward surface, 
     the first projection includes the first upward surface, the first downward surface and the second downward surface, 
     the second projection includes a second upward surface, a third downward surface and a fourth downward surface, wherein when the toner container is oriented in the predetermined direction, the third downward surface and the fourth downward surface extend so as to go as goes in the first rotational direction, and at least a part of the third downward surface is in the position which is closer the fourth downward surface in the circumferential direction to the central axis than the fourth downward surface in the radial direction and which is different from a position of the fourth downward surface in the circumferential direction, and 
     at least a part of the second upward surface is above at least a part of the fourth downward surface. 
     Structure Example A33 
     A toner container according to Structure Example A32, wherein for the first projection, a part of the first downward surface is upstream of the second downward surface in the first rotational direction, and 
     wherein for the second projection, a part of the third downward surface is upstream of the fourth downward surface in the first rotational direction. 
     Structure Example A34 
     A toner container according to any one of Structure Examples A18-A31, wherein when the upward surface is a first upward surface, the projection has a third downward surface, a fourth downward surface and a second upward surface having 150-210 degree inclusive rotational symmetry shapes, about the central axis, of the first downward surface, the second downward surface and the first upward surface, respectively. 
     Structure Example A35 
     A toner container according to any one of Structure Examples A18-A31, wherein when the upward surface is a first upward surface, the projection has a third downward surface, a fourth downward surface and a second upward surface having 180 degree rotational symmetry shapes, about the central axis, of the first downward surface, the second downward surface and the first upward surface, respectively. 
     Structure Example A36 
     A toner container according to any one of Structure Examples A18-A31, wherein the projection includes a first projection and a second projection which is provided at a position different from a position at which the first projection is provided in the circumferential direction, 
     wherein the first projection has the upward surface and the second downward surface, and 
     the second projection has the first downward surface. 
     Structure Example A37 
     A toner container according to Structure Example A36, wherein the second projection is provided at a position diametrically opposite to the first projection. 
     Structure Example A38 
     A toner container according to any one of Structure Examples A18-A37, wherein the first downward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A39 
     A toner container according to any one of Structure Examples A18-A38, wherein the second downward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A40 
     A toner container according to any one of Structure Examples A18-A39, wherein the second downward surface is longer than the first downward surface, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A41 
     A toner container according to any one of Structure Examples A18-A40, wherein the upward surface is longer than the first downward surface, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A42 
     A toner container according to any one of Structure Examples A18-A41, wherein the upward surface is longer than the second downward surface, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A43 
     A toner container ( 220 ,  2320 ,  23210 ,  2420 ,  2520 ,  2530 ,  320 ,  3220 ,  520 ,  5120 ,  620 ,  820 ,  920 ,  10020 ,  1120 ) comprising: 
     an accommodating portion ( 201 ,  2401 ,  501 ,  901 ) configured to accommodate toner; 
     a discharge portion ( 202   a ,  2402 Ag,  2502   k   2 ,  2503   k   2 ,  302   a ,  502   a ,  902 Bk,  10020 Be) provided with an opening for discharging the toner in the accommodating portion to an outside; 
     a rotation member ( 203 ,  903 A,  1003 ) rotatable about a central axis as a rotational axis relative to the discharge portion in a first rotational direction and a second rotational direction which is opposed to the first rotational direction, 
     a projection ( 202   b ,  2302   b ,  23102   b ,  2402 Bb,  2502   b ,  2503   b ,  304 ,  3104 ,  3204 ,  502   b ,  5102   b ,  604 ,  804 ,  8104 ,  8204 ,  8304 ,  903 Bg,  1003   b ,  1132   b ) provided below the opening of the discharge portion and having inner peripheral surface ( 202   b   1 ,  202   b   10 ,  804   a   11 ) the facing inward in a radial direction of an imaginary circle centered on the central axis, when the toner container is oriented in a predetermined direction in which the central axis extends in a direction of gravity and at least a part of the discharge portion is below the accommodating portion, wherein the opening of the discharge portion is configured to face outward in the radial direction, 
     wherein when the toner container is oriented in the predetermined direction, 
     the projection includes a downward surface ( 204   a   1 ,  204   a   2 ,  204   b   1 ,  204   b   2 ,  2304   a   1 ,  2304   b   1 ,  23104   a   1 ,  23104   b   1 ,  2604   b   1 ,  2604   a   2 ,  304   a   1 ,  304   a   2 ,  304   b   1 ,  304   b   2 ,  3104   a   2 ,  3104   b   2 ,  3204   a   1 ,  3204   b   1 ,  604 Aa 1 ,  604 Ba 1 ,  604 Ab 1 ,  604 Bb 1 ,  804   a   1 ,  804   a   2 ,  804   b   1 ,  804   b   2 ) facing downward, and an upward surface ( 204   a   3 ,  204   b   3 ,  2304   a   2 ,  2304   b   2 ,  23104   a   2 ,  23104   b   2 ,  2604   a   3 ,  304   a   3 ,  304   b   3 ,  3104   a   3 ,  3104   b   3 ,  3204   a   3 ,  3204   b   3 ,  604 Ba 2 ,  604 Bb 2 ,  804   a   3 ) facing upward in the radial direction, outside the inner peripheral surface and inside the opening of the discharge portion in the radial direction, when the toner container is oriented in the predetermined direction, 
     the downward surface extends so as to go up as goes in the first rotational direction, 
     an inner edge line ( 2304   a   4 ,  2304   b   4 ,  23104   a   4 ,  23104   b   4 ) of the downward surface on a side closer to the central axis in the radial direction includes an inner upstream edge line ( 2304   a   4 U,  2304   b   4 U,  23104   a   4 U,  23104   b   4 U) provided on an upstream side in the first rotational direction and an inner downstream edge line provided on a downstream side of the inside upstream edge line in the first rotational direction, 
     the inner downstream edge line is more remote from the central axis in the radial direction than the inner upstream edge line, and 
     at least a part of the upward surface is above at least a part of the downward surface. 
     Structure Example A44 
     A toner container according to Structure Example A43, wherein the inner upstream edge line and the inner edge line defines a first arcuation and a second arcuation centered on the central axis, respectively, the second arcuation having a radius larger than that of the first arcuation, and wherein the inner edge line includes an inner middle edge line which extends in the radial direction between the first arcuation and the second arcuation to connect between the first arcuation and the second arcuation. 
     Structure Example A45 
     A toner container according to Structure Example A43, wherein the inner upstream edge line and the inner downstream edge line are smoothly continues with each other. 
     Structure Example A46 
     A toner container according to any one of Structure Examples A43-A45, wherein an outer edge line of the downward surface on a side more remote from the central axis in the radial direction includes an outer upstream edge line on an upstream side in the first rotational direction the first rotational direction and an outer downstream edge line on a downstream side of the outer upstream edge line in the first rotational direction, wherein the outer downstream edge line is more remote from the central axis in the radial direction than the outer upstream edge line. 
     Structure Example A47 
     A toner container according to any one of Structure Examples A43-A46, wherein when the toner container is oriented in the predetermined direction, the upward surface extends so as to go up as goes in the second rotational direction. 
     Structure Example A48 
     A toner container according to Structure Example A47, wherein the upward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A49 
     A toner container according to any one of Structure Examples A43-A46, wherein the upward surface is perpendicular to the central axis. 
     Structure Example A50 
     A toner container according to any one of Structure Examples A43-A46, wherein when the toner container is oriented in the predetermined direction, the upward surface extends so as to go up as goes in the first rotational direction. 
     Structure Example A51 
     A toner container according to any one of Structure Examples A43-A50, wherein the upward surface is configured to be exposed to an outside of the toner container. 
     Structure Example A52 
     A toner container according to any one of Structure Examples A43-A51, wherein a cavity is provided above the upward surface of the projection, when the toner container is oriented in the predetermined direction. 
     Structure Example A53 
     A toner container according to any one of Structure Examples A43-A52, wherein the projection has a downstream side end surface which extends upward along the central axis from a downstream end of the upward surface in the second rotational direction and which faces a downstream side in the first rotational direction, when the toner container is oriented in the predetermined direction. 
     Structure Example A54 
     A toner container according to any one of Structure Examples A43-A53, wherein a region of the downward surface corresponding to the inner downstream edge line overlaps the upward surface as viewed in the direction of the central axis. 
     Structure Example A55 
     A toner container according to any one of Structure Examples A43-A54, wherein the projection includes a connecting portion connecting a downstream end of the downward surface in the first rotational direction and an upstream end of the upward surface in the second rotational direction with each other. 
     Structure Example A56 
     A toner container according to any one of Structure Examples A43-A55, wherein as the discharge portion is viewed in the direction of the central axis, the upward surface and the downward surface are in positions closer to the inner peripheral surface than to the opening in the radial direction. 
     Structure Example A57 
     A toner container according to any one of Structure Examples A43-A55, wherein as the discharge portion is viewed in the direction of the central axis, a distance from the inner peripheral surface to the upward surface and a distance from the inner peripheral surface to the downward surface are not more than 30% a distance from the inner peripheral surface to the opening. 
     Structure Example A58 
     A toner container according to any one of Structure Examples A43-A57, wherein the downward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A59 
     A toner container according to any one of Structure Examples A1-A58, wherein the rotatable member is provided outside the discharge portion in the radial direction. 
     Structure Example A60 
     A toner container according to Structure Example A59, wherein the rotatable member is configured to rotate about the central axis between a close position for closing the opening and an open position for opening the opening. 
     Structure Example A61 
     A toner container according to Structure Example A60, wherein an outer surface of the rotation member extending in the direction of the central axis is provided with a rotation member opening for exposing the opening of the discharge portion to an outside of the toner container when the rotatable member is in the open position, and 
     wherein an outer surface opposite from the rotatable member opening across the central axis is provided with a recess recessing inward in the radial direction. 
     Structure Example A62 
     A toner container according to Structure Example A61, wherein the projection is provided at a position closer to the central axis in the radial direction than to the recess, as the toner container is viewed in the direction of the central axis. 
     Structure Example A63 
     A toner container according to Structure Example A61 or A62, wherein the projection is inside a width of the rotation member opening in a direction perpendicular to the central axis, as viewed in the radial direction. 
     Structure Example A64 
     A toner container according to Structure Example A63, wherein the discharge portion has a first opposing surface and a second opposing surface at an outer surface extending in the direction of the central axis, the first opposing surface and the second opposing surface being opposed to each other with a gap therebetween, 
     wherein the first opposing surface and the first opposing surface are exposed through the rotation member opening, when the rotation member is in the close position. 
     Structure Example A65 
     A toner container according to Structure Example A64, wherein the first opposing surface and the second opposing surface are parallel with each other, and 
     wherein when a line parallel with the first opposing surface and passing through a center portion between the first opposing surface and the second opposing surface is a first imaginary line, and a line provided by rotating the first imaginary line about the central axis by 90 degree, the second imaginary line passes through the opening. 
     Structure Example A66 
     A toner container according to any one of Structure Examples A60-A65, wherein the rotation member is rotatable in the first rotational direction from the close position to the open position. 
     Structure Example A67 
     A toner container according to Structure Example A66, further comprising a seal for sealing between the rotation member and the discharge portion when the rotation member is in the close position. 
     Structure Example A68 
     A toner container according to any one of Structure Examples A1-A67, wherein the inner peripheral surface of the projection is centered on the central axis. 
     Structure Example A69 
     A toner container according to Structure Example A68, wherein the inner peripheral surface of the projection is cylindrical. 
     Structure Example A70 
     A toner container according to Structure Example A68, wherein the inner peripheral surface of the projection is constituted by a plurality of flat surfaces surrounding the central axis. 
     Structure Example A71 
     A toner container according to any one of Structure Examples A1-A70, wherein when the toner container is oriented in the predetermined direction, the projection is configured to project downward with respect to a lower surface of the toner container. 
     Structure Example A72 
     A toner container according to Structure Example A71, wherein when the toner container is oriented in the predetermined direction, the projection is capable of taking a projection position in which the projection projects downward with respect to the lower surface of the toner container, and a retracted position in which the projection is retracted so as not to project downward with respect to the lower surface. 
     Structure Example A73 
     A toner container according to Structure Example A71 or A72, wherein, when the toner container is oriented in the predetermined direction, the projection is provided on the lower surface of the discharge portion. 
     Structure Example A74 
     A toner container according to Structure Example A73, wherein the projection is projected downward through a hole provided in a bottom surface of the rotatable member. 
     Structure Example A75 
     A toner container according to Structure Example A71 or A72, further comprising a support member supporting the discharge portion, and wherein the projection is provided on the lower surface of the support member, when the toner container is oriented in the predetermined direction. 
     Structure Example A76 
     A toner container according to Structure Example A75, wherein the support member defines a space which is surrounded by a side surface extending in the direction of the central axis and which is provided with the discharge portion, and wherein the side surface of the support member is provided with a side surface opening configured to expose the opening of the discharge portion. 
     Structure Example A77 
     A toner container according to any one of Structure Examples A1-A71, wherein the projection is capable of transitioning with respect to the discharge portion between a first attitude in which the projection projects in the direction of the central axis and a second attitude in which the projection projects in a direction crossing the central axis. 
     Structure Example A78 
     A toner container according to any one of Structure Examples A1-A71, wherein the projection is supported by the discharge portion so as to be movable relative to the discharge portion in the direction of the central axis. 
     Structure Example A79 
     A toner container according to Structure Example A78, wherein a shaft member extending in the direction of the central axis, rotatable about the central axis relative to the discharge portion and movable in the direction of the central axis, 
     wherein a guide portion configured to guide the shaft member so that the shaft member is moved in the direction of the central axis when the shaft member is rotated, and 
     wherein the projection is supported by a lower end portion of the shaft member so as to move in the direction of the central axis together with the shaft member, when the toner container is oriented in the predetermined direction. 
     Structure Example A80 
     A toner container according to Structure Example A79, wherein in a state in which the toner container is oriented in the predetermined direction, 
     the guide portion includes a guide groove which is a cylindrical member provided outside the shaft member in the radial direction and which extends so as to go up in the direction of the central axis as goes in a predetermined rotational direction of the shaft member in a peripheral surface around the central axis, 
     the shaft member is provided with a projection projecting in the radial direction and engaged with the guide groove, and is configured such that the shaft member moves upward in the direction of the central axis while the projection of the shaft member is guided by the guide groove of the guide portion, when the shaft member is rotated in the predetermined rotational direction. 
     Structure Example A81 
     A toner container according to Structure Example A80, wherein an operating portion provided outside the shaft member in the radial direction so as to be rotatable with the shaft member, and wherein when the operating portion is rotated in the predetermined rotational direction about the central axis, the shaft member moves upward in the direction of the central axis while being rotated and guided by the guide portion so that the projection moves upward with the shaft member, in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A82 
     A toner container according to Structure Example A64 or A65, wherein as viewed in a direction perpendicular to the central axis, the projection is in a region between the first opposing surface and the second opposing surface in a direction along which the first opposing surface and the second opposing surface are arranged. 
     Structure Example A83 
     A toner container according to any one of Structure Examples A1-A71, wherein the discharge portion includes a pipe configured to pass the toner when the toner in the accommodating portion is discharged to an outside of the toner container, and the pipe is provided with a receiving opening for receiving the toner from the accommodating portion and an outlet for discharging the toner received through the receiving opening, wherein the opening is the outlet of the pipe. 
     Structure Example A84 
     A toner container according to Structure Example A83, wherein when the toner container is oriented in the predetermined direction, the receiving opening of the pipe includes a portion which faces upward and which extends so as to go in the radial direction as goes downward. 
     Structure Example A85 
     A toner container according to Structure Example A84, further comprising a pipe support member supporting the pipe, wherein when the toner container is oriented in the predetermined direction, the projection projects downward from a lower surface of the pipe support member. 
     Structure Example A86 
     A toner container according to any one of Structure Examples A83-A85, wherein the pipe is capable of transitioning to an attitude in which the outlet of the pipe faces downward. 
     Structure Example A87 
     A toner container according to any one of Structure Examples A1-A82, wherein the opening provided in an outer surface of the discharge portion extending along the central axis. 
     Structure Example A88 
     A toner container according to any one of Structure Examples A1-A82, wherein the opening of the discharge portion is provided by breaking a part of an outer surface of the discharge portion extending in the direction of the central axis. 
     Structure Example A89 
     A toner container according to Structure Example A87, wherein the discharge portion is provided with a pull-tab connected with a part of the outer surface, and 
     wherein the part of the outer surface is separated from the discharge portion to provide the opening of the discharge portion by pulling the pull-tab. 
     Structure Example A90 
     A toner container ( 100 ,  1050 ,  1051 ,  1052 ,  1060 ,  1070 ,  1080 ,  220 ,  2320 ,  23210 ,  2420 ,  2520 ,  2530 ,  2820 ,  520 ,  5120 ,  920 ,  10020 ,  1120 ) comprising: 
     an accommodating portion ( 101 ,  1015 ,  10151 ,  201 ,  2401 ,  2801 ,  501 ,  901 ) configured to accommodate toner; 
     a discharge portion ( 102 ,  1025 ,  202 ,  2302 ,  23102 ,  2402 A,  2502 ,  2503 ,  2802 ,  502 ,  5102 ,  902 ,  1002 A,  1102 ) configured to be provided with an opening ( 102   a ,  202   a ,  2402 Ag,  2502   k   2 ,  2503   k   2 ,  2802   a ,  502   a ,  902 Bk,  10020 Be) for discharging the toner in the accommodating portion to an outside; 
     a projection ( 102   b ,  1020   b ,  1021   b ,  1023   b ,  1024   b ,  1026   b ,  1027   b ,  1028   b ,  202   b ,  2302   b ,  23102   b ,  2402 Bb,  2502   b ,  2503   b ,  2802   b ,  502   b ,  5102   b ,  903 Bg,  1003   b ,  1132   b ) which includes an inner peripheral surface ( 102   b   1 ,  202   b   1 ,  202   b   10 ) centered on the central axis and which is provided below the opening of the discharge portion and projects downward, when the toner container is oriented in a predetermined direction in which the central axis extends in a direction of gravity and at least a part of the discharge portion is below the accommodating portion, 
     wherein the opening of the discharge portion is configured to face outward in a radial direction of an imaginary circle centered on the central axis, and 
     wherein when the toner container is oriented in the predetermined direction, 
     the projection has an upward surface ( 104   a   2 ,  104   b   2 ,  1041   a   2 ,  1042   b   2 ,  1043   a   2 ,  1043   b   2 ,  1044   a   2 ,  1046   a   2 ,  1047   a   2 ,  1048   a   2 ,  204   a   3 ,  204   b   3 ,  2304   a   2 ,  2304   b   2 ,  23104   a   2 ,  23104   b   2 ,  2604   a   3 ) facing upward outside the inner peripheral surface and inside the opening of the discharge portion in the radial direction, and 
     when a circumferential direction of the imaginary circle is a first circumferential direction, and a circumferential direction opposite to the first circumferential direction is a second circumferential direction, the upward surface extends so as to go up as goes in the second circumferential direction. 
     Structure Example A91 
     A toner container according to Structure Example A90, wherein the upward surface is configured to be exposed to an outside of the toner container. 
     Structure Example A92 
     A toner container according to Structure Example A90 or A91, wherein when the toner container is oriented in the predetermined direction, a cavity is provided above the upward surface of the projection. 
     Structure Example A93 
     A toner container according to any one of Structure Examples A90-A92, wherein the projection has a downstream side end surface extending upward along the central axis from a downstream end of the upward surface in the second circumferential direction and facing downstream side in the first circumferential direction, when the toner container is oriented in the predetermined direction. 
     Structure Example A94 
     A toner container according to any one of Structure Examples A90-A93, wherein the upward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees as the toner container is viewed in the radial direction in the state in which the toner container is oriented in the predetermined direction. 
     Structure Example A95 
     A toner container according to any one of Structure Examples A90-A94, wherein as the discharge portion is viewed in the direction of the central axis, the upward surface is provided at a position closer to inner peripheral surface than to the opening, in the radial direction. 
     Structure Example A96 
     A toner container according to Structure Example A95, wherein as the discharge portion is viewed in the direction of the central axis, a distance from the inner peripheral surface to the upward surface is not more than 30% a distance from the inner peripheral surface to the opening. 
     Structure Example A97 
     A toner container according to any one of Structure Examples A90-A96, wherein when the toner container is oriented in the predetermined direction, the projection has a downward surface which faces downward and which extends so as to go up as goes in the first circumferential direction, and 
     wherein at least a part of the upward surface is above at least a part of the downward surface. 
     Structure Example A98 
     A toner container according to Structure Example A97, wherein the downward surface overlaps the upward surface, as viewed in the direction of the central axis. 
     Structure Example A99 
     A toner container according to Structure Example A97 or A98, wherein the projection includes a connecting portion connecting a downstream end of the downward surface in the first circumferential direction and an upstream end of the upward surface in the second circumferential direction with each other. 
     Structure Example A100 
     A toner container according to any one of Structure Examples A97-A99, wherein the downward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A101 
     A toner container according to any one of Structure Examples A97-A100, wherein the upward surface is longer than the downward surface, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A102 
     A toner container according to any one of Structure Examples A97-A101, wherein the projection includes a first projection and a second projection which is provided at a position different from a position at which the first position is provided in a circumferential direction of the imaginary circle, 
     wherein the upward surface and the downward surface are first upward surface and second downward surface, respectively, the first projection includes the first upward surface and the second downward surface, and the second projection includes a second upward surface and a fourth downward surface. 
     Structure Example A103 
     A toner container according to Structure Example A102, wherein the second upward surface and the fourth downward surface have 150-210 degree inclusive rotation symmetry shapes of the first upward surface and second downward surface about the central axis, respectively. 
     Structure Example A104 
     A toner container according to Structure Example A103, wherein the second upward surface and the fourth downward surface have 180 degree rotation symmetry of the first upward surface and second downward surface about the central axis. 
     Structure Example A105 
     A toner container according to any one of Structure Examples A97-A101, wherein the projection includes a first projection and a second projection which is provided at a position different from a position at which the first projection is in the circumferential direction, 
     wherein the first projection includes the upward surface, and wherein the second projection includes the downward surface. 
     Structure Example A106 
     A toner container according to Structure Example A105, wherein the second projection is provided at a position diametrically opposite to the first projection. 
     Structure Example A107 
     A toner container ( 220 ,  2420 ,  2520 ,  2530 ,  2820 ,  320 ,  520 ,  5120 ,  620 ,  820 ,  920 ,  10020 ,  1120 ) comprising: 
     an accommodating portion ( 201 ,  2401 ,  2801 ,  501 ,  901 ) configured to accommodate toner; 
     a discharge portion ( 202 ,  2402 A,  2502 ,  2503 ,  2802 ,  302 ,  502 ,  5102 ,  902 ,  1002 A,  1102 ) configured to be provided with an opening ( 202   a ,  2402 Ag,  2502   k   2 ,  2503   k   2 ,  2802   a ,  302   a ,  502   a ,  902 Bk,  10020 Be) for discharging the toner in the accommodating portion to an outside; 
     a projection ( 202   b ,  2402 Bb,  2502   b ,  2503   b ,  2802   b ,  304 ,  3104 ,  502   b ,  5102   b ,  604 ,  804 ,  8104 ,  8204 ,  8304 ,  903 Bg,  1003   b ,  1132   b ) which includes an inner peripheral surface ( 202   b   1 ,  202   b   10 ,  804   a   11 ) centered on the central axis and which is provided below the opening of the discharge portion and projects downward, when the toner container is oriented in a predetermined direction in which the central axis extends in a direction of gravity and at least a part of the discharge portion is below the accommodating portion, 
     wherein the opening of the discharge portion is configured to face outward in a radial direction of an imaginary circle centered on the central axis, 
     wherein when the toner container is oriented in the predetermined direction, 
     the projection has a first downward surface ( 204   a   1 ,  304   a   1 ,  604 Aa 1 ,  804   a   1 ,  204   b   1 ,  304   b   1 ,  604 Ab 1 ,  804   b   1 ), and a second downward surface ( 204   a   2 ,  304   a   2 ,  604 Ba 1 ,  804   a   2 ,  204   b   2 ,  304   b   2 ,  604 Bb 1 ,  804   b   2 ) which face downward, and an upward surface ( 204   a   3 ,  204   b   3 ,  2604   a   3 ,  304   a   3 ,  304   b   3 ,  3104   a   3 ,  3104   b   3 ,  604 Ba 2 ,  604 Bb 2 ,  804   a   3 ) which faces upward, outside the inner peripheral surface and inside the opening of the discharge portion in the radial direction, when the toner container is oriented in the predetermined direction, 
     when a circumferential direction of the imaginary circle is a first circumferential direction, and a circumferential direction opposite to the first circumferential direction is a second circumferential direction, the first downward surface and the second downward surface extend so as to go up as go in the first circumferential direction, and at least a part of the first downward surface is at a position which is closer to the central axis in the radial direction than the second downward surface is and which is different from a position at which the second downward surface is provided in the circumferential direction, and 
     at least a part of the upward surface is above at least a part of the second downward surface. 
     Structure Example A108 
     A toner container according to Structure Example A107, wherein when the toner container is oriented in the predetermined direction, the upward surface extends so as to go up as goes in the second circumferential direction. 
     Structure Example A109 
     A toner container according to Structure Example A107 or A108, wherein the upward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees as the toner container is viewed in the radial direction in the state in which the toner container is oriented in the predetermined direction. 
     Structure Example A110 
     A toner container according to Structure Example A107, wherein the upward surface is a surface perpendicular to the central axis. 
     Structure Example A111 
     A toner container according to Structure Example A107, wherein when the toner container is oriented in the predetermined direction, the upward surface extends so as to go up as goes in the first circumferential direction. 
     Structure Example A112 
     A toner container according to any one of Structure Examples A107-A111, wherein the upward surface is configured to be exposed to an outside of the toner container. 
     Structure Example A113 
     A toner container according to any one of Structure Examples A107-A112, wherein a cavity is provided above the upward surface of the projection, when the toner container is oriented in the predetermined direction. 
     Structure Example A114 
     A toner container according to any one of Structure Examples A107-A113, wherein the projection has a downstream side end surface extending upward along the central axis from a downstream end of the upward surface in the second circumferential direction and facing downstream side in the first circumferential direction, when the toner container is oriented in the predetermined direction. 
     Structure Example A115 
     A toner container according to any one of Structure Examples A107-A114, wherein the second downward surface overlaps the upward surface as viewed in the direction of the central axis. 
     Structure Example A116 
     A toner container according to any one of Structure Examples A107-A115, wherein the projection includes a connecting portion connecting a downstream end of the second downward surface in the first circumferential direction and an upstream end of the upward surface in the second circumferential direction with each other. 
     Structure Example A117 
     A toner container according to any one of Structure Examples A107-A116, wherein as the discharge portion is viewed in the direction of the central axis, the upward surface, the first downward surface and the second downward surface are provided at positions closer to the inner peripheral surface than to the opening in radial direction. 
     Structure Example A118 
     A toner container according to Structure Example A117, wherein as the discharge portion is viewed in the direction of the central axis, a distance from the inner peripheral surface to the upward surface, a distance from the inner peripheral surface to the first downward surface, and a distance from the inner peripheral surface to the second downward surface are not more than 30% a distance from the inner peripheral surface to the opening. 
     Structure Example A119 
     A toner container according to any one of Structure Examples A107-A118, wherein the second downward surface is movable relative to the first downward surface between an alignment position in which the second downward surface is aligned with the first downward surface in the circumferential direction, and a non-alignment position in which the second downward surface is not aligned with the first downward surface in the circumferential direction. 
     Structure Example A120 
     A toner container according to any one of Structure Examples A107-A118, wherein the second downward surface is movable relative to the first downward surface between an alignment position in which the second downward surface is aligned with the first downward surface in the radial direction and a non-alignment position in which the second downward surface is not aligned with the first downward surface. 
     Structure Example A121 
     A toner container according to any one of Structure Examples A107-A120, wherein the projection includes a first projection and a second projection which is provided at a position different from a position at which the first projection is provided in the circumferential direction, 
     wherein the upward surface is a first upward surface, 
     the first projection includes the first upward surface, the first downward surface and the second downward surface, 
     the second projection includes a second upward surface, a third downward surface and a fourth downward surface, 
     wherein when the toner container is oriented in the predetermined direction, 
     the third downward surface and the fourth downward surface extend so as to go up as goes in the first circumferential direction, and at least a part of the third downward surface is at a position which is closer to the central axis in the radial direction than the fourth downward surface is and which is different from a position at which the fourth downward surface is provided in the circumferential direction, and 
     at least a part of the second upward surface is above at least a part of the fourth downward surface. 
     Structure Example A122 
     A toner container according to Structure Example A121, wherein for the first projection, a part of the first downward surface of the first projection is upstream of the second downward surface in the first circumferential direction, and for the second projection, a part of the third downward surface of the second projection is upstream of the fourth downward surface in the first circumferential direction. 
     Structure Example A123 
     A toner container according to any one of Structure Examples A107-A120, wherein when the upward surface is a first upward surface, the projection has a third downward surface, a fourth downward surface and a second upward surface having 150-210 degree inclusive rotational symmetry shapes, about the central axis, of the first downward surface, the second downward surface and the first upward surface, respectively. 
     Structure Example A124 
     A toner container according to any one of Structure Examples A107-A120, wherein when the upward surface is a first upward surface, the projection has a third downward surface, a fourth downward surface and a second upward surface having 180 degree rotational symmetry shapes, about the central axis, of the first downward surface, the second downward surface and the first upward surface, respectively. 
     Structure Example A125 
     A toner container according to any one of Structure Examples A107-A120, wherein the projection includes a first projection and a second projection which is provided at a position different from a position at which the first projection is provided in the circumferential direction, wherein the first projection has the upward surface and the second downward surface, and the second projection has the first downward surface. 
     Structure Example A126 
     A toner container according to Structure Example A125, wherein the second projection is provided at a position diametrically opposite to the first projection. 
     Structure Example A127 
     A toner container according to any one of Structure Examples A107-A126, wherein the first downward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A128 
     A toner container according to any one of Structure Examples A107-A127, wherein the second downward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A129 
     A toner container according to any one of Structure Examples A107-A128, wherein the second downward surface is longer than the first downward surface, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A130 
     A toner container according to any one of Structure Examples A107-A129, wherein the upward surface is longer than the first downward surface, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A131 
     A toner container according to any one of Structure Examples A107-A130, wherein the upward surface is longer than the second downward surface, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A132 
     A toner container ( 220 ,  2320 ,  23210 ,  2420 ,  2520 ,  2530 ,  2820 ,  320 ,  3220 ,  520 ,  5120 ,  620 ,  820 ,  920 ,  10020 ,  1120 ) comprising: 
     an accommodating portion ( 201 ,  2401 ,  2801 ,  501 ,  901 ) configured to accommodate toner; 
     a discharge portion ( 202 ,  2302 ,  23102 ,  2402 A,  2502 ,  2503 ,  2802 ,  302 ,  502 ,  5102 ,  902 ,  1002 A,  1102 ) configured to be provided with an opening ( 202   a ,  2402 Ag,  2502   k   2 ,  2503   k   2 ,  2802   a ,  302   a ,  502   a ,  902 Bk,  10020 Be) for discharging the toner in the accommodating portion to an outside; 
     a projection ( 202   b ,  2302   b ,  23102   b ,  2402 Bb,  2502   b ,  2503   b ,  2802   b ,  304 ,  3104 ,  3204 ,  502   b ,  5102   b ,  604 ,  804 ,  8104 ,  8204 ,  8304 ,  903 Bg,  1003   b ,  1132   b ) which includes an inner peripheral surface ( 202   b   1 ,  202   b   10 ,  804   a   11 ) centered on the central axis and which is provided below the opening of the discharge portion and projects downward, when the toner container is oriented in a predetermined direction in which the central axis extends in a direction of gravity and at least a part of the discharge portion is below the accommodating portion, 
     wherein the opening of the discharge portion is configured to face outward in a radial direction of an imaginary circle centered on the central axis, and 
     wherein when the toner container is oriented in the predetermined direction, 
     the projection includes a downward surface ( 204   a   1 ,  204   a   2 ,  204   b   1 ,  204   b   2 ,  2304   a   1 ,  2304   b   1 ,  23104   a   1 ,  23104   b   1 ,  2604   b   1 ,  2604   a   2 ,  304   a   1 ,  304   a   2 ,  304   b   1 ,  304   b   2 ,  3104   a   2 ,  3104   b   2 ,  3204   a   1 ,  3204   b   1 ,  604 Aa 1 ,  604 Ba 1 ,  604 Ab 1 ,  604 Bb 1 ,  804   a   1 ,  804   a   2 ,  804   b   1 ,  804   b   2 ) facing downward and an upward surface ( 204   a   3 ,  204   b   3 ,  2304   a   2 ,  2304   b   2 ,  23104   a   2 ,  23104   b   2 ,  2604   a   3 ,  304   a   3 ,  304   b   3 ,  3104   a   3 ,  3104   b   3 ,  3204   a   3 ,  3204   b   3 ,  604 Ba 2 ,  604 Bb 2 ,  804   a   3 ) facing upward in the radial direction, outside the inner peripheral surface and inside the opening of the discharge portion in the radial, when the toner container is oriented in the predetermined direction, 
     when a circumferential direction of the imaginary circle is a first circumferential direction, and a circumferential direction opposite to the first circumferential direction is a second circumferential direction, the downward surface extend so as to go up as goes in the first circumferential direction, 
     an inner edge line ( 2304   a   4 ,  2304   b   4 ,  23104   a   4 ,  23104   b   4 ) of the downward surface on a side closer to the central axis in the radial direction includes an inner upstream edge line ( 2304   a   4 U,  2304   b   4 U,  23104   a   4 U,  23104   b   4 U) on an upstream side in the first circumferential direction, and an inner downstream edge line ( 2304   a   4 D,  2304   b   4 D,  23104   a   4 D,  23104   b   4 D) on a downstream side of the inner upstream edge line in the first circumferential direction, 
     the inner downstream edge line is more remote from the central axis in the radial direction than the inner upstream edge line, and 
     at least a part of the upward surface is above at least a part of the downward surface. 
     Structure Example A133 
     A toner container according to Structure Example A132, wherein the inner upstream edge line and the inner downstream edge line defines a first arcuation and a second arcuation which are centered on the central axis, respectively, the second arcuation having a radius larger than that of the first arcuation, and wherein the inner edge line includes an inner middle edge line which extends in the radial direction between the first arcuation and the second arcuation to connect between the first arcuation and the second arcuation. 
     Structure Example A134 
     A toner container according to Structure Example A133, wherein the inner upstream edge line and the inner downstream edge line are smoothly continues with each other. 
     Structure Example A135 
     A toner container according to any one of Structure Examples A132-A134, wherein an outer edge line of the downward surface on a side more remote from the central axis in the radial direction includes an outer upstream edge line on an upstream side, and an outer downstream edge line on a downstream side of the outer upstream edge line in the first circumferential direction, wherein the outer downstream edge line is more remote from the central axis in the radial direction than the outer upstream edge line. 
     Structure Example A136 
     A toner container according to any one of Structure Examples A132-A135, wherein when the toner container is oriented in the predetermined direction, the upward surface extends so as to go up as goes in the second circumferential direction. 
     Structure Example A137 
     A toner container according to Structure Example A136, wherein the upward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A138 
     A toner container according to any one of Structure Examples A132-A135, wherein the upward surface is perpendicular to the central axis. 
     Structure Example A139 
     A toner container according to any one of Structure Examples A132-A135, wherein when the toner container is oriented in the predetermined direction, the upward surface extends so as to go up as goes in the first circumferential direction. 
     Structure Example A140 
     A toner container according to any one of Structure Examples A132-A139, wherein the upward surface is configured to be exposed to an outside of the toner container. 
     Structure Example A141 
     A toner container according to any one of Structure Examples A132-A140, wherein a cavity is provided above the upward surface of the projection, when the toner container is oriented in the predetermined direction. 
     Structure Example A142 
     A toner container according to any one of Structure Examples A132-A141, wherein the projection has a downstream side end surface extending upward along the central axis from a downstream end of the upward surface in the second circumferential direction and facing downstream side in the first circumferential direction, when the toner container is oriented in the predetermined direction. 
     Structure Example A143 
     A toner container according to any one of Structure Examples A132-A142, wherein a region of the downward surface corresponding to the inner downstream edge line overlaps the upward surface as viewed in the direction of the central axis. 
     Structure Example A144 
     A toner container according to any one of Structure Examples A132-A143, wherein the projection includes a connecting portion connecting a downstream end of the downward surface in the first circumferential direction and an upstream end of the upward surface in the second circumferential direction with each other. 
     Structure Example A145 
     A toner container according to any one of Structure Examples A132-A144, wherein as the discharge portion is viewed in the direction of the central axis, the upward surface and the downward surface are in positions closer to the inner peripheral surface than the opening in the radial direction. 
     Structure Example A146 
     A toner container according to Structure Example A145, wherein as the discharge portion is viewed in the direction of the central axis, a distance from the inner peripheral surface to the upward surface and a distance from the inner peripheral surface to the downward surface are not more than 30% a distance from the inner peripheral surface to the opening. 
     Structure Example A147 
     A toner container according to any one of Structure Examples A132-A146, wherein the downward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees, as the toner container is viewed in the radial direction in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A148 
     A toner container according to any one of Structure Examples A90-A132, wherein the inner peripheral surface of the projection is a cylindrical surface. 
     Structure Example A149 
     A toner container according to any one of Structure Examples A90-A132, wherein the inner peripheral surface of the projection is constituted by a plurality of flat surfaces surrounding the central axis. 
     Structure Example A150 
     A toner container according to any one of Structure Examples A90-A149, wherein the projection is configured to project downward with respect to a lower surface of the toner container, when the toner container is oriented in the predetermined direction. 
     Structure Example A151 
     A toner container according to Structure Example A150, wherein the projection is capable of taking a projection position in which the projection projects downward with respect to the lower surface of the toner container, and a retracted position in which the projection is retracted so as not to project with respect to the lower surface, when the toner container is oriented in the predetermined direction. 
     Structure Example A152 
     A toner container according to Structure Example A150 or A151, wherein the projection is provided on the lower surface of the discharge portion, when the toner container is oriented in the predetermined direction. 
     Structure Example A153 
     A toner container according to Structure Example A152, further comprising a rotatable member rotatable relative to the discharge portion in an outside of the discharge portion in the radial direction, 
     wherein the projection projects downward through a hole provided in a bottom surface of the rotatable member, when the toner container is oriented in the predetermined direction. 
     Structure Example A154 
     A toner container according to Structure Example A150 or A151, further comprising a support member supporting the discharge portion, 
     wherein the projection is provided on a lower surface of the support member, when the toner container is oriented in the predetermined direction. 
     Structure Example A155 
     A toner container according to Structure Example A154, wherein the support member defines a space which is surrounded by a side surface extending in the direction of the central axis and which is provided with the discharge portion, and. 
     the side surface of the support member is provided with a side surface opening configured to expose the opening of the discharge portion. 
     Structure Example A156 
     A toner container according to any one of Structure Examples A90-A150, wherein the projection is capable of transitioning with respect to the discharge portion between a first attitude in which it projects in the direction of the central axis and a second attitude in which it projects in a direction crossing the central axis. 
     Structure Example A157 
     A toner container according to any one of Structure Examples A90-A150, wherein the projection it supported by the discharge portion so as to be movable relative to the discharge portion in the direction of the central axis. 
     Structure Example A158 
     A toner container according to Structure Example A157, wherein a shaft member extending in the direction of the central axis, rotatable about the central axis relative to the discharge portion and movable in the direction of the central axis, and a guide portion for guiding the shaft member so that the shaft member moves in the direction of the central axis when the shaft member is rotated, and 
     wherein the projection it supported by a lower end portion of the shaft member so as to move in the direction of the central axis together with the shaft member, when the toner container is oriented in the predetermined direction. 
     Structure Example A159 
     A toner container according to Structure Example A158, wherein in a state in which the toner container is oriented in the predetermined direction, 
     wherein the guide portion includes a guide groove which is a cylindrical member provided outside the shaft member in the radial direction and which extends so as to go up in the direction of the central axis as goes in a predetermined rotational direction of the shaft member in a peripheral surface around the central axis, and 
     wherein the shaft member is provided with a projection projecting in the radial direction and engaged with the guide groove, and is configured such that the shaft member moves upward in the direction of the central axis while the projection of the shaft member is guided by the guide groove of the guide portion, when the shaft member is rotated in the predetermined rotational direction. 
     Structure Example A160 
     A toner container according to Structure Example A159, further comprising an operating portion provided outside the shaft member in the radial direction so as to be rotatable with the shaft member, wherein when the operating portion is rotated in the predetermined rotational direction about the central axis, the shaft member moves upward in the direction of the central axis while being rotated and guided by the guide portion so that the projection moves upward with the shaft member, in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A161 
     A toner container according to any one of Structure Examples A90-A153, wherein the discharge portion has a first opposing surface and a second opposing surface at an outer surface extending in the direction of the central axis, the first opposing surface and the second opposing surface being opposed to each other with a gap therebetween, and 
     the projection is between the first opposing surface and the second opposing surface in a direction in which the first opposing surface and the second opposing surface are arranged, as viewed in a direction perpendicular to the central axis. 
     Structure Example A162 
     A toner container according to Structure Example A161, wherein the first opposing surface and the second opposing surface are parallel with each other, and 
     wherein when a line parallel with the first opposing surface and passing through a center portion between the first opposing surface and the second opposing surface is a first imaginary line, and a line provided by rotating the first imaginary line about the central axis by 90 degrees, the second imaginary line passes through the opening. 
     Structure Example A163 
     A toner container according to any one of Structure Examples A90-A150, wherein the discharge portion includes a pipe configured to pass the toner when the toner in the accommodating portion is discharged to an outside of the toner container, and the pipe is provided with a receiving opening for receiving the toner from the accommodating portion and an outlet for discharging the toner received through the receiving opening, 
     wherein the opening is the outlet of the pipe. 
     Structure Example A164 
     A toner container according to Structure Example A163, wherein when the toner container is oriented in the predetermined direction, the receiving opening faces upward, and the pipe includes a portion extending so as to go in the radial direction as goes downward. 
     Structure Example A165 
     A toner container according to Structure Example A164, further comprising a pipe support member for supporting the pipe, and 
     wherein when the toner container is oriented in the predetermined direction, the projection projects downward from a lower surface of the pipe support member. 
     Structure Example A166 
     A toner container according to any one of Structure Examples A163-A165, wherein the pipe is capable of transitioning to an attitude in which the outlet of the pipe faces downward. 
     Structure Example A167 
     A toner container according to any one of Structure Examples A90-A162, wherein the opening is provided at an outer surface of the discharge portion extending along the central axis. 
     Structure Example A168 
     A toner container according to any one of Structure Examples A90-A162, wherein the opening of the discharge portion is configured to be provided by a part of an outer surface of the discharge portion being broken, the part of the outer surface of the discharge portion extending in the direction of the central axis. 
     Structure Example A169 
     A toner container according to Structure Example A168, wherein the discharge portion is provided with a pull-tab connected with a part of the outer surface, and 
     wherein the part of the outer surface is separated from the discharge portion to provide the opening of the discharge portion by the pull-tab being pulled. 
     Structure Example A170 
     A toner container ( 420 ) comprising: 
     an accommodating portion ( 201 ) configured to accommodate toner; 
     a discharge portion ( 402 ,  430 ) configured to be provided with an opening ( 430   a ) for discharging the toner in the accommodating portion to an outside; 
     a rotation member ( 203 ) rotatable about a central axis as a rotational axis relative to the discharge portion in a first rotational direction and a second rotational direction which is opposed to the first rotational direction; and 
     a projection ( 402   b ) provided below the opening of the discharge portion and having inner peripheral surface ( 202   b   1 ) facing inward in a radial direction of an imaginary circle centered on the central axis, when the toner container is oriented in a predetermined direction in which the central axis extends in a direction of gravity and at least a part of the discharge portion is below the accommodating portion, 
     wherein the opening of the discharge portion faces downward, and 
     wherein when the toner container is oriented in the predetermined direction, 
     the projection has an upward surface ( 204   a   3 ,  204   b   3 ) facing upward outside the inner peripheral surface in the radial direction, and 
     the upward surface extends so as to go up as goes in the second rotating direction. 
     Structure Example A171 
     A toner container ( 420 ) comprising: 
     an accommodating portion ( 201 ) configured to accommodate toner: 
     a discharge portion ( 402 ,  430 ) configured to provide an opening ( 430   a ) for discharging the toner in the accommodating portion to an outside; 
     a rotation member ( 203 ) rotatable about a central axis as a rotational axis relative to the discharge portion in a first rotational direction and a second rotational direction which is opposed to the first rotational direction; and 
     a projection ( 402   b ) provided below the opening of the discharge portion and having an inner peripheral surface ( 202   b   1 ) facing inward in a radial direction of an imaginary circle centered on the central axis, when the toner container is oriented in a predetermined direction in which the central axis extends in a direction of gravity and at least a part of the discharge portion is below the accommodating portion, wherein the opening of the discharge portion faces downward, 
     wherein when the toner container is oriented in the predetermined direction, 
     the projection has, outside the inner peripheral surface in the radial direction, a first downward surface ( 204   a   1 ,  204   b   1 ), a second downward surface ( 204   a   2 ,  204   b   2 ) which face downward, and an upward surface ( 204   a   3 ,  204   b   3 ) facing upward, and 
     the first downward surface and the second downward surface extend so as to go up as goes in the first rotational direction, and at least a part of the first downward surface is provided at a position which is closer to the central axis in the radial direction than the second downward surface is and which is different from a position at which the second downward surface is provided in a circumferential direction of the imaginary circle, and 
     at least a part of the upward surface is above at least a part of the second downward surface. 
     Structure Example A172 
     A toner container ( 420 ) comprising: 
     an accommodating portion ( 201 ) configured to accommodate toner; 
     a discharge portion ( 402 ,  430 ) configured to provide an opening ( 430   a ) for discharging the toner in the accommodating portion to an outside; and 
     a projection ( 402   b ) which includes an inner peripheral surface ( 202   b   1 ) centered on the central axis, which is provided below the opening of the discharge portion, and which projects downward, when the toner container is oriented in a predetermined direction in which the central axis extends in a direction of gravity and at least a part of the discharge portion is below the accommodating portion, 
     wherein the opening of the discharge portion faces downward, 
     wherein when the toner container is oriented in the predetermined direction, the projection has an upward surface ( 204   a   3 ,  204   b   3 ) facing upward outside the inner peripheral surface in a radial direction of an imaginary circle centered on the central axis, and 
     when a circumferential direction of the imaginary circle is a first circumferential direction, and a circumferential direction opposite to the first circumferential direction is a second circumferential direction, the upward surface extends so as to go up as goes in the second circumferential direction. 
     Structure Example A173 
     A toner container ( 420 ) comprising: 
     an accommodating portion ( 201 ) configured to accommodate toner; 
     a discharge portion ( 402 ,  430 ) configured to provide an opening ( 430   a ) for discharging the toner in the accommodating portion to an outside; and 
     a projection ( 402   b ) which includes an inner peripheral surface ( 202   b   1 ) centered on the central axis and which is provided below the opening of the discharge portion and projects downward, when the toner container is oriented in a predetermined direction in which the central axis extends in a direction of gravity and at least a part of the discharge portion is below the accommodating portion, 
     wherein the opening of the discharge portion faces downward, and 
     wherein when the toner container is oriented in the predetermined direction, 
     the projection has a first downward surface ( 204   a   1 ,  204   b   1 ), a second downward surface ( 204   a   2 ,  204   b   2 ), and an upward surface ( 204   a   3 ,  204   b   3 ) facing upward, outside the inner peripheral surface in a radial direction of an imaginary circle centered on the central axis, when the toner container is oriented in the predetermined direction, 
     when a circumferential direction of the imaginary circle is a first circumferential direction, and a circumferential direction opposite to the first circumferential direction is a second circumferential direction, the first downward surface and the second downward surface extend so as to go up as go in the first circumferential direction, and at least a part of the first downward surface is at a position which is closer to the central axis in the radial direction than the second downward surface is and which is different from a position at which the second downward surface is provided in the circumferential direction, and 
     at least a part of the upward surface is above at least a part of the second downward surface. 
     Structure Example A174 
     A toner container according to any one of Structure Examples A170-A173, wherein when the opening is a first opening, 
     the discharge portion including a receiving member for receiving the toner from the accommodating portion, and a discharge member provided with the first opening through which the toner received from the receiving member is discharged to an outside of the toner container, 
     the receiving member is provided with a second opening in a side surface extending in the direction of the central axis, and 
     the discharge member is movable relative to the receiving member between a first position in which the discharge member projects in the radial direction through the second opening toward the receiving member, and the first opening is exposed to an outside of the toner container, and a second position retracted from the first position toward the central axis. 
     Structure Example A175 
     A toner container according to Structure Example A174, wherein the rotatable member is rotatable about the central axis between a close position for closing the second opening of the receiving member and an open position for opening the second opening of the receiving member, and 
     wherein when the rotatable member is in the close position, the discharge member is in the second position, and movement of the discharge member to the first position is restricted by the rotatable member, and when the rotatable member is in the open position, the discharge member is movable between the first position and the second position. 
     Structure Example A176 
     A toner container ( 720 ,  7120 ,  7220 ,  7320 ) comprising: 
     an accommodating portion ( 201 ) configured to accommodate toner; 
     a discharge portion ( 302 ) configured to be provided with an opening ( 302   a ) for discharging the toner in the accommodating portion to an outside; 
     a rotation member ( 203 ) rotatable about a central axis as a rotational axis relative to the discharge portion in a first rotational direction and a second rotational direction which is opposed to the first rotational direction; and 
     a projection ( 704 ,  7204 ,  7304 ) provided below the opening of the discharge portion and projecting downward, the projection having an inner peripheral surface ( 704 Ae) facing a radial direction of an imaginary circle centered on the central axis, when the toner container is oriented in a predetermined direction in which the central axis extends in a direction of gravity and at least a part of the discharge portion is below the accommodating portion, 
     wherein the opening of the discharge portion faces outward in the radial direction, 
     wherein the projection includes a first projection member ( 704 A,  7104 A,  7204 A,  7304 A) and a second projection member ( 704 B,  7104 B,  7204 B,  7304 B), and the first projection member is rotatable relative to the second projection member about the central axis, 
     wherein when the toner container is oriented in the predetermined direction, 
     the first projection member has a downstream side end surface ( 704 Aa 1 ,  7104 Aa 1 ,  7104 Ab 1 ,  7204 Aa 1 ) which is a downstream side end surface in the first rotational direction, and 
     the second projection member has an upward surface ( 704 Ba 2 ,  704 Bb 2 ,  7104 Ba 2 ,  7104 Bb 2 ,  7204 Ba 2 ,  7304 Ba 2 ) facing upward. 
     Structure Example A177 
     A toner container according to Structure Example A176, wherein the second projection member has a downward surface extending so as to go up as goes in the first rotational direction, the downward surface being outside the downstream side end surface in the radial direction, and 
     wherein at least a part of the upward surface is above at least a part of the downward surface. 
     Structure Example A178 
     A toner container according to Structure Example A177, wherein the downstream side end surface of the first projection member is restricted by the second projection member so that it does not reach a downstream side of a downstream end, in the first rotational direction, of the downward surface of the second projection member. 
     Structure Example A179 
     A toner container according to Structure Example A178, wherein the second projection member has a downward surface extending so as to go up as goes in the first rotational direction, the downward surface being outside the downstream side end surface in the radial direction, and 
     wherein at least a part of the upward surface is above at least a part of the downward surface. 
     Structure Example A180 
     A toner container according to Structure Example A179, wherein the downstream side end surface of the first projection member is restricted by the second projection member so that the downstream side end surface does not reach a downstream side of a downstream end, in the first rotational direction, of the downward surface of the second projection member. 
     Structure Example A181 
     A toner container according to any one of Structure Examples A176-A180, wherein the downstream side end surface of the first projection member is a surface parallel with the central axis. 
     Structure Example A182 
     A toner container according to any one of Structure Examples A176-A181, wherein the first projection member has a first inner peripheral surface extending in the direction of the central axis, and the second projection member has a second inner peripheral surface extending in the direction of the central axis and centered on the central axis, and 
     wherein the first projection member is rotatable relative to the second projection member inside the second inner peripheral surface relative to the second inner peripheral surface of the second projection member in the radial direction. 
     Structure Example A183 
     A toner container according to Structure Example A182, further comprising a movable member movable relative to the first projection member in the direction of the central axis inside the first inner peripheral surface of the first projection member, the movement member is restricted in rotation relative to the second projection member about the central axis, and an urging member for urging the movable member away from the accommodating portion in the direction of the central axis, wherein the movable member is configured to rotate the first projection member relative to the second projection member in the first rotational direction by being moved toward the accommodating portion in the direction of the central axis. 
     Structure Example A184 
     A toner container according to Structure Example A182, further comprising an urging member for urging the first projection member relative to the second projection member in the direction of the central axis away from the accommodating portion, 
     wherein the second projection member is provided with a guide groove, and 
     wherein the first projection member is provided with an engaging portion for engagement with the guide groove of the second projection member, and movable relative to the second projection member in the direction of the central axis inside the second inner peripheral surface of the second projection member, and 
     wherein the first projection member is configured to be rotated in the first rotational direction relative to the second projection member while the engaging portion of the first projection member is guided by the guide groove of the second projection member, by being moved in the direction of the central axis toward the accommodating portion. 
     Structure Example A185 
     A toner container ( 100 ,  1050 ,  1051 ,  1052 ,  1060 ,  1070 ,  1080 ,  220 ,  2320 ,  23210 ,  2420 ,  2520 ,  2530 ,  2820 ,  520 ,  5120 ,  920 ,  10020 ,  1120 ) comprising: 
     an accommodating portion ( 101 ,  1015 ,  10151 ,  201 ,  2401 ,  2801 ,  501 ,  901 ) configured to accommodate toner; 
     a discharge portion ( 102 ,  1025 ,  202 ,  2302 ,  23102 ,  2402 A,  2502 ,  2503 ,  2802 ,  502 ,  5102 ,  902 ,  1002 A,  1102 ) configured to be provided with an opening ( 102   a ,  202   a ,  2402 Ag,  2502   k   2 ,  2503   k   2 ,  2802   a ,  502   a ,  902 Bk,  10020 Be) for discharging the toner in the accommodating portion to an outside, the discharge portion being aligned with the accommodating portion in the first direction (D 1 ); and 
     a projection ( 102   b ,  1020   b ,  1021   b ,  1023   b ,  1024   b ,  1026   b ,  1027   b ,  1028   b ,  202   b ,  2302   b ,  23102   b ,  2402 Bb,  2502   b ,  2503   b ,  2802   b ,  502   b ,  5102   b ,  903 Bg,  1003   b ,  1132   b ) provided below the opening of the discharge portion and projects downward, when the toner container is oriented in a predetermined direction in which the first direction is a direction of gravity and at least a part of the discharge portion is below the accommodating portion, 
     wherein the opening of the discharge portion faces outward in a second direction perpendicular to the first direction, and 
     wherein when the toner container is oriented in the predetermined direction, the projection has a downward guide surface ( 104   a   1 ,  104   b   1 ,  1041   b   1 ,  1042   a   1 ,  1043   a   1 ,  1043   b   1 ,  1044   a   1 ,  1046   a   1 ,  1047   a   1 ,  1048   a   1 ,  204   a   1 ,  204   a   2 ,  204   b   1 ,  204   b   2 ,  2304   a   1 ,  2304   b   1 ,  23104   a   1 ,  23104   b   1 ,  2604   b   1 ,  2604   a   2 ) facing downward, and an upward guide surface ( 104   a   2 ,  104   b   2 ,  1041   a   2 ,  1042   b   2 ,  1043   a   2 ,  1043   b   2 ,  1044   a   2 ,  1046   a   2 ,  1047   a   2 ,  1048   a   2 ,  204   a   3 ,  204   b   3 ,  2304   a   2 ,  2304   b   2 ,  23104   a   2 ,  23104   b   2 ,  2604   a   3 ) at least a part of which is above at least the downward guide surface and which faces upward, and 
     at least a part of the upward guide surface is above at least a part of the downward guide surface. 
     Structure Example A186 
     A toner container according to Structure Example A185, wherein the downward guide surface is a push surface. 
     Structure Example A187 
     A toner container according to Structure Example A185 or A186, wherein the upward guide surface is configured to be exposed to an outside of the toner container. 
     Structure Example A188 
     A toner container according to any one of Structure Examples A185-A187, wherein when the toner container is oriented in the predetermined direction, a cavity is provided above the upward guide surface of the projection. 
     Structure Example A189 
     A toner container according to any one of Structure Examples A185-A188, wherein as the toner container the toner container oriented in the predetermined direction is viewed in a direction perpendicular to the first direction, 
     the downward guide is configured to extend so as to go up as goes in the first horizontal direction of horizontal directions, and 
     the upward guide surface is configured to extend so as to go up as goes in a second horizontal direction which is opposite to the first horizontal direction. 
     Structure Example A190 
     A toner container according to Structure Example A189, wherein when the toner container is oriented in the predetermined direction, 
     the projection includes a connecting portion connecting a downstream end of the downward guide surface in the first horizontal direction and an upstream end of the upward guide surface in the second horizontal direction, with each other. 
     Structure Example A191 
     A toner container according to Structure Example A189 or A190, wherein when the toner container is oriented in the predetermined direction, the projection has a contacted surface which extend upward from a downstream end of the upward guide surface in the second horizontal direction along the first direction and which faces downward in the first horizontal direction. 
     Structure Example A192 
     A toner container according to any one of Structure Examples A189-A191, wherein the downward guide surface includes a first downward guide surface and a second downward guide surface which face downward, and 
     wherein as the toner container is viewed in a direction perpendicular to the first direction, when the toner container is oriented in the predetermined direction, 
     at least a part of the first downward guide surface is at a position different from a position at which the second downward guide is provided in the horizontal direction. 
     Structure Example A193 
     A toner container according to Structure Example A192, wherein when the toner container is oriented in the predetermined direction, 
     the projection includes a connecting portion connecting a downstream end of the second downward guide surface in the first horizontal direction and an upstream end of the upward guide surface in the second horizontal direction with each other. 
     Structure Example A194 
     A toner container according to Structure Example A192 or A193, wherein as viewed in the first direction, the second downward guide surface overlaps the upward guide surface. 
     Structure Example A195 
     A toner container according to any one of Structure Examples A185-A194, wherein when the toner container is oriented in the predetermined direction, the projection is configured to project downward with respect to a lower surface of the toner container. 
     Structure Example A196 
     A toner container according to Structure Example A195, wherein when the toner container is oriented in the predetermined direction, the projection is capable of taking a projection position in which the projection projects downward with respect to the lower surface of the toner container, and a retracted position in which the projection is retracted so as not to project with respect to the lower surface. 
     Structure Example A197 
     A toner container according to Structure Example A195, wherein when the toner container is oriented in the predetermined direction, the projection is provided at a lower surface of the discharge portion. 
     Structure Example A198 
     A toner container according to Structure Example A195, further comprising a support member supporting the discharge portion, wherein the projection is provided on a lower surface of the support member, when the toner container is oriented in the predetermined direction. 
     Structure Example A199 
     A toner container according to Structure Example A198, wherein the support member includes a space surrounded by a side surface extending in the first direction and provided with the discharge portion, and 
     wherein the side surface of the support member is provided with a side surface opening configured to expose the opening of the discharge portion. 
     Structure Example A200 
     A toner container according to any one of Structure Examples A185-A195, wherein the projection is capable of transitioning relative to the discharge portion between a first attitude in which the projection projects in the first direction and a second attitude in which the projection projects in a direction crossing the first direction. 
     Structure Example A201 
     A toner container according to any one of Structure Examples A185-A195, wherein the discharge portion includes a pipe configured to pass the toner when the toner in the accommodating portion is discharged to an outside of the toner container, and the pipe is provided with a receiving opening for receiving the toner from the accommodating portion and an outlet for discharging the toner received through the receiving opening, wherein the opening is the outlet of the pipe. 
     Structure Example A202 
     A toner container according to Structure Example A201, wherein when the toner container is oriented in the predetermined direction, the receiving opening faces upward, and the pipe includes a portion extending so as to go in the second direction as goes downward. 
     Structure Example A203 
     A toner container according to Structure Example A201 or A202, further comprising a pipe support member supporting the pipe, wherein when the toner container is oriented in the predetermined direction, the projection projects downward from a lower surface of the pipe support member. 
     Structure Example A204 
     A toner container according to any one of Structure Examples A201-A203, wherein the pipe is capable of transitioning to an attitude in which the outlet of the pipe faces downward. 
     Structure Example A205 
     A toner container according to any one of Structure Examples A185-A200, wherein the opening is provided in an outer surface of the discharge portion extending in the first direction. 
     Structure Example A206 
     A toner container according to any one of Structure Examples A185-A200, wherein the opening of the discharge portion is provided by a part of an outer surface of the discharge portion being broken, the part of the outer surface of the discharge portion extending in the first direction. 
     Structure Example A207 
     A toner container according to Structure Example A206, wherein the discharge portion is provided with a pull-tab connected with a part of the outer surface, and 
     wherein the part of the outer surface is separated from the discharge portion to provide the opening of the discharge portion by the pull-tab being pulled. 
     Structure Example A208 
     a toner container according to any one of Structure Examples A185-A207, further comprising a rotatable member rotatable relative to the discharge portion about a central axis as a rotational axis extending in the first direction in a first rotational direction and a second rotational direction opposite to the first rotational direction. 
     Structure Example A209 
     A toner container according to Structure Example A208, wherein the projection includes a first projection and a second projection which is provided at the position different from a position at which the first projection is provided in a circumferential direction of an imaginary circle centered on the central axis, 
     wherein the first projection has the upward guide surface and the downward guide surface, and 
     wherein the second projection has a 150-210 degree inclusive rotation symmetry shape of the first projection about the central axis. 
     Structure Example A210 
     A toner container according to Structure Example A208, wherein the projection includes a first projection and a second projection which is provided at the position different from a position at which the first projection is provided in a circumferential direction of an imaginary circle centered on the central axis, 
     wherein the first projection has the upward guide surface, 
     wherein the second projection has the downward guide surface. 
     Structure Example A211 
     A toner container according to Structure Example A208, wherein the projection includes a first projection and a second projection which is provided at the position different from a position at which the first projection is provided in a circumferential direction of an imaginary circle having a center on the central axis, 
     wherein the downward guide surface includes a first downward guide surface and a second downward guide surface which face downward, and 
     wherein the upward guide surface is a first upward guide surface, 
     the first projection has the first upward guide surface, the first downward guide surface and a second downward surface, 
     the second projection has a second upward guide surface, a third downward guide surface and a fourth downward guide surface, and 
     the second upward guide surface, the third downward guide surface and the fourth downward guide surface have shapes which are 150-210 degree inclusive rotation symmetry, about the central axis, of the first upward guide surface, the first downward guide surface and the second downward guide surface, respectively. 
     Structure Example A212 
     A toner container according to any one of Structure Examples A208-A211, wherein the rotatable member is provided outside the discharge portion in the radial direction of an imaginary circle centered on the central axis. 
     Structure Example A213 
     A toner container according to any one of Structure Examples A208-A212, wherein the rotatable member is configured to rotate about the central axis between a close position for closing the opening and an open position for opening the opening. 
     Structure Example A214 
     A toner container according to Structure Example A213, wherein an outer surface of the rotation member extending in the direction of the central axis is provided with a rotation member opening for exposing the opening of the discharge portion to an outside of the toner container when the rotatable member is in the open position, and 
     wherein an outer surface in the surface opposite to the rotational member across the central axis is provided with the recess recessing inward in a radial direction of an imaginary circle centered on the central axis. 
     Structure Example A215 
     A toner container according to Structure Example A214, wherein the projection is at a position closer to the central axis in the radial direction than the recess is, as the toner container is viewed in the direction of the central axis. 
     Structure Example A216 
     A toner container according to Structure Example A213, wherein an outer surface of the rotation member extending in the direction of the central axis is provided with a rotation member opening for exposing the opening of the discharge portion to an outside of the toner container when the rotatable member is in the open position, and 
     wherein as viewed in a radial direction of an imaginary circle centered on the central axis, the projection is in a width of the rotation member opening in a direction perpendicular to the central axis. 
     Structure Example A217 
     A toner container according to Structure Example A214, wherein the discharge portion has a first opposing surface and a second opposing surface at an outer surface thereof extending in the direction of the central axis, the first opposing surface and the second opposing surface being opposed to each other with a gap therebetween, 
     wherein the first opposing surface and the first opposing surface are exposed through the rotation member opening, when the rotation member is in the close position. 
     Structure Example A218 
     A toner container according to Structure Example A217, wherein the first opposing surface and the second opposing surface are parallel with each other, and 
     wherein when a line parallel with the first opposing surface and passing through a center portion between the first opposing surface and the second opposing surface is a first imaginary line, a second imaginary line which is a line provided by rotating the first imaginary line about the central axis by 90 degrees passes through the opening. 
     Structure Example A219 
     A toner container according to any one of Structure Examples A213-A218, wherein the rotation member is rotatable from the close position to the open position is the first rotational direction. 
     Structure Example A220 
     A toner container according to Structure Example A219, further comprising a seal for sealing between the rotation member and the discharge portion when the rotation member is in the close position. 
     Structure Example A221 
     A toner container according to any one of Structure Examples A185-A211, wherein the projection has an inner peripheral guide surface extending in the first direction about the central axis. 
     Structure Example A222 
     A toner container according to Structure Example A221, wherein the inner peripheral guide surface of the projection is a cylindrical surface. 
     Structure Example A223 
     A toner container according to Structure Example A221, wherein the inner peripheral guide surface of the projection includes a plurality of flat surfaces around the central axis. 
     Structure Example A224 
     A toner container ( 100 ,  1050 ,  1051 ,  1052 ,  1060 ,  1070 ,  1080 ,  220 ,  2320 ,  23210 ,  2420 ,  2520 ,  2530 ,  2820 ,  320 ,  3220 ,  520 ,  5120 ,  620 ,  720 ,  7220 ,  820 ,  920 ,  10020 ,  1120 ) comprising: 
     an accommodating portion ( 101 ,  1015 ,  10151 ,  201 ,  2401 ,  2801 ,  501 ,  901 ) configured to accommodate toner; 
     a discharge portion ( 102 ,  1025 ,  202 ,  2302 ,  23102 ,  2402 A,  2502 ,  2503 ,  2802 ,  302 ,  502 ,  5102 ,  902 ,  1002 A,  1102 ) configured to be provided with an opening ( 102   a ,  202   a ,  2402 Ag,  2502   k   2 ,  2503   k   2 ,  2802   a ,  302   a ,  502   a ,  902 Bk,  10020 Be) for discharging the toner in the accommodating portion to an outside, the discharge portion being aligned with the accommodating portion in a first direction (D 1 ); and 
     a projection ( 102   b ,  1020   b ,  1021   b ,  1023   b ,  1024   b ,  1026   b ,  1027   b ,  1028   b ,  202   b ,  2302   b ,  23102   b ,  2402 Bb,  2502   b ,  2503   b ,  2802   b ,  304 ,  3104 ,  3204 ,  502   b ,  5102   b ,  604 ,  704 ,  7204 ,  804 ,  8104 ,  8204 ,  8304 ,  903 Bg,  1003   b ,  1132   b ) provided below the opening of the discharge portion and projecting downward, when the toner container is oriented in a predetermined direction in which the first direction is a direction of gravity and at least a part of the discharge portion is below the accommodating portion, 
     wherein the opening of the discharge portion faces outward in a second direction perpendicular to the first direction, and 
     wherein when the toner container is oriented in the predetermined direction, the projection has a downward guide surface) facing downward, an upward engagement surface ( 104   a   2 ,  104   b   2 ,  1041   a   2 ,  1042   b   2 ,  1043   a   2 ,  1043   b   2 ,  1044   a   2 ,  1046   a   2 ,  1047   a   2 ,  1048   a   2 ,  204   a   3 ,  204   b   3 ,  2304   a   2 ,  2304   b   2 ,  23104   a   2 ,  23104   b   2 ,  2604   a   3 ,  304   a   3 ,  304   b   3 ,  3104   a   3 ,  3104   b   3 ,  3204   a   3 ,  3204   b   3 ,  604 Ba 2 ,  604 Bb 2 ,  704 Ba 2 ,  704 Bb 2 ,  7204 Ba 2 ,  804   a   3 ) facing upward, wherein at least a part of the upward engagement surface is above at least a part of the downward guide surface, and 
     at least a part of the upward engagement surface is above at least a part of the downward guide surface. 
     Structure Example A225 
     A toner container according to Structure Example A224, wherein the upward engagement surface is configured to be exposed to an outside of the toner container. 
     Structure Example A226 
     A toner container according to Structure Example A224 or A225, wherein a cavity is provided above the upward engaging surface of the projection when the toner container is oriented in the predetermined direction. 
     Structure Example A227 
     A toner container according to any one of Structure Examples A224-A226, wherein the downward guide surface is a push surface. 
     Structure Example A228 
     A toner container according to any one of Structure Examples A224-A227, 
     wherein when the toner container is oriented in the predetermined direction, 
     as the toner container is viewed in a direction perpendicular to the first direction, 
     the downward guide surface extends so as to go up as goes in a first horizontal direction of the horizontal directions. 
     Structure Example A229 
     A toner container according to Structure Example A228, wherein when the toner container is oriented in the predetermined direction, the upward engagement surface is a surface parallel with the first horizontal direction. 
     Structure Example A230 
     A toner container according to Structure Example A228 or A229, wherein when the toner container is oriented in the predetermined direction, the upward engagement surface extends so as to go up as goes in the first horizontal direction. 
     Structure Example A231 
     A toner container according to any one of Structure Examples A228-A230, wherein when the toner container is oriented in the predetermined direction, 
     the projection includes a connecting portion connecting a downstream end of the downward guide surface in the first horizontal direction and a downstream end of the upward engagement surface in the first horizontal direction, with each other. 
     Structure Example A232 
     A toner container according to any one of Structure Examples A228-A231, wherein when the toner container is oriented in the predetermined direction, the projection has a contacted surface extending upward in the first direction from an upstream end of the upward engagement surface in the first horizontal direction and facing a downstream side on the first horizontal direction. 
     Structure Example A233 
     A toner container according to any one of Structure Examples A228-A232, wherein the downward guide surface includes a first downward guide surface and a second downward guide surface which face downward, 
     wherein as the toner container is viewed in a direction perpendicular to the first direction when the toner container is oriented in the predetermined direction, 
     at least a part of the first downward guide surface is at a position different from a position at which the second downward guide surface is provided in the horizontal direction. 
     Structure Example A234 
     A toner container according to Structure Example A233, wherein when the toner container is oriented in the predetermined direction, 
     the projection includes a connecting portion connecting a downstream end of the second downward guide surface in the first horizontal direction and a downstream end of the upward engagement surface in the first horizontal direction, with each other. 
     Structure Example A235 
     A toner container according to Structure Example A233 or A234, wherein as viewed in the first direction, the second downward guide surface overlaps the upward engagement surface. 
     Structure Example A236 
     A toner container according to any one of Structure Examples A224-A235, wherein when the toner container is oriented in the predetermined direction, the projection is configured to project downward with respect to a lower surface of the toner container. 
     Structure Example A237 
     A toner container according to any one of Structure Examples A224-A236, wherein the opening is provided in an outer surface of the discharge portion extending in the first direction. 
     Structure Example A238 
     A toner container according to any one of Structure Examples A224-A237, further comprising a rotatable member rotatable relative to the discharge portion about a central axis as a rotational axis extending in the first direction in a first rotational direction and a second rotational direction opposite to the first rotational direction. 
     Structure Example A239 
     A toner container according to Structure Example A238, wherein the projection includes a first projection and a second projection which is provided at the position different from a position at which the first projection is provided in a circumferential direction of an imaginary circle centered on the central axis, 
     wherein the first projection has the upward engagement surface and the downward guide surface, and 
     the second projection has a 150-210 degree inclusive rotation symmetry shape of the first projection about the central axis. 
     Structure Example A240 
     A toner container according to Structure Example A233 or A234, further comprising a rotatable member rotatable, relative to the discharge portion about a central axis as a rotational axis extending in the first direction, in a first rotational direction and a second rotational direction opposite to the first rotational direction, 
     wherein the projection includes a first projection and a second projection which is provided at the position different from a position at which the first projection is provided in a circumferential direction of an imaginary circle centered on the central axis, and 
     wherein the upward engagement surface is a first upward engagement surface, 
     the first projection has the first upward engagement surface, the first downward guide surface and a second downward surface, 
     the second projection has a second upward engagement surface, a third downward guide surface and a fourth downward guide surface, and 
     the second upward engagement surface, the third downward guide surface and the fourth downward guide have shapes which are 150-210 degree rotational symmetric, about the central axis, of the first upward engagement surface, the first downward guide surface and the second downward guide surface. 
     Structure Example A241 
     A toner container according to any one of Structure Examples A224-A237, wherein the projection has an inner peripheral guide surface centered on a central axis extending in the first direction. 
     Structure Example A242 
     A toner container according to any one of Structure Examples A224-A240, wherein the projection is supported by the discharge portion so as to be movable in the first direction relative to the discharge portion. 
     Structure Example A243 
     A toner container according to Structure Example A78, further comprising a shaft member rotatable about the central axis relative to the discharge portion and movable in the direction of the central axis, and 
     a guide configured to guide the shaft member so that the shaft member is moved in the direction of the central axis when the shaft member is rotated, 
     wherein the projection is supported by a lower end portion of the shaft member so as to move in the direction of the central axis together with the shaft member, when the toner container is oriented in the predetermined direction. 
     Structure Example A244 
     A toner container according to Structure Example A243, wherein in a state in which the toner container is oriented in the predetermined direction, 
     the guide is a cylindrical member provided outside of the shaft member in the radial direction and is provided with a guide groove which extends on a peripheral surface around the central axis so as to go up in the direction of the central axis as goes in a predetermined rotational direction of the shaft member, 
     the shaft member is provided with a projection projecting in the radial direction and engaged with the guide groove, and 
     when the shaft member is rotated in the predetermined rotational direction, the projection of the shaft member is guided by the guide groove of the guide so that the shaft member moves upward in the direction of the central axis. 
     Structure Example A245 
     A toner container according to Structure Example A244, further comprising an operating portion provided outside the shaft member in the radial direction so as to be rotatable with the shaft member, and wherein when the operating portion is rotated about the central axis in a state in which the toner container is oriented in the predetermined direction, the shaft member is rotated and is guided by the guide to move upward so that the projection is moved upward together with the shaft member. 
     Structure Example A246 
     A toner container ( 100 ,  1050 ,  1051 ,  1052 ,  1060 ,  1070 ,  1080 ,  220 ,  2320 ,  23210 ,  2420 ,  2520 ,  2530 ,  520 ,  5120 ,  920 ,  10020 ,  1120 ) mountable to and dismountable from a mounting portion ( 106 ,  206 ) of an image forming apparatus, the mounting portion including a rotatable guided member, the toner container comprising: 
     an accommodating portion ( 101 ,  1015 ,  10151 ,  201 ,  2401 ,  501 ,  901 ) configured to accommodate toner; 
     a discharge portion ( 102 ,  1025 ,  202 ,  2302 ,  23102 ,  2402 A,  2502 ,  2503 ,  502 ,  5102 ,  902 ,  1002 A,  1102 ) configured to be provided with an opening ( 102   a ,  202   a ,  2402 Ag,  2502   k   2 ,  2503   k   2 ,  502   a ,  902 Bk,  10020 Be) for discharging the toner in the accommodating portion to an outside; a rotatable member ( 103 ,  203 ,  903 A,  1003 ) rotatable in a first rotational direction relative to the discharge portion about a central axis as a rotational axis and a second rotational direction opposed to the first rotational direction; and 
     a projection ( 102   b ,  1020   b ,  1021   b ,  1023   b ,  1024   b ,  1026   b ,  1027   b ,  1028   b ,  202   b ,  2302   b ,  23102   b ,  2402 Bb,  2502   b ,  2503   b ,  502   b ,  5102   b ,  903 Bg,  1003   b ,  1132   b ) provided below the opening of the discharge portion and having inner peripheral surface ( 102   b   1 ,  202   b   1 ,  202   b   10 ) facing inward in a radial direction of an imaginary circle centered on the central axis, when the toner container is oriented in a predetermined direction in which the central axis extends in a direction of gravity and at least a part of the discharge portion is below the accommodating portion, 
     wherein the opening of the discharge portion is configured to face outward in the radial direction, and 
     wherein when the toner container is oriented in the predetermined direction, the projection has a downward guide surface ( 104   a   1 ,  104   b   1 ,  1041   b   1 ,  1042   a   1 ,  1043   a   1 ,  1043   b   1 ,  1044   a   1 ,  1046   a   1 ,  1047   a   1 ,  1048   a   1 ,  204   a   1 ,  204   a   2 ,  204   b   1 ,  204   b   2 ,  2304   a   1 ,  2304   b   1 ,  23104   a   1 ,  23104   b   1 ,  2604   b   1 ,  2604   a   2 ) facing downward and an upward guide surface facing upward outside of the inner peripheral surface and inside of the opening of the discharge portion in the radial direction, and an upward guide surface ( 104   a   2 ,  104   b   2 ,  1041   a   2 ,  1042   b   2 ,  1043   a   2 ,  1043   b   2 ,  1044   a   2 ,  1046   a   2 ,  1047   a   2 ,  1048   a   2 ,  204   a   3 ,  204   b   3 ,  2304   a   2 ,  2304   b   2 ,  23104   a   2 ,  23104   b   2 ,  2604   a   3 ) facing upward, 
     when the toner container is moved down in the direction of the central axis toward the mounting portion in a state in which the toner container is oriented in the predetermined direction, 
     the downward guide is configured to guide the guided member so that the guided member is rotated about the central axis in the first rotational direction, and 
     the upward guide surface is configured to guide the guided member so that the guided member is moved upward after the guided member is rotated in the first rotational direction by the downward surface. 
     Structure Example A247 
     A toner container according to Structure Example A246, wherein the rotatable member is provided outside the discharge portion in the radial direction. 
     Structure Example A248 
     A toner container according to any one of Structure Examples A246-A247, wherein the rotatable member is rotatable about the central axis between a close position for closing the opening and an open position for opening the opening, and wherein the rotatable member is provided with a rotatable member opening for exposing the opening of the discharge portion to an outside of the toner container when the rotatable member is in the open position. 
     Structure Example A249 
     A toner container according to Structure Example A248, wherein a rotational direction of the rotatable member from the close position toward the open position is the first rotational direction. 
     Structure Example A250 
     A toner container according to Structure Example A248 or A249, further comprising a seal for sealing between the rotatable member and the discharge portion when the rotatable member is in the close position. 
     Structure Example A251 
     A toner container according to any one of Structure Examples A248-A250, wherein the mounting portion includes a positioning portion projecting inward in the radial direction, and the discharge portion includes a positioned portion having a first opposing surface and a second opposing surface which extend in a direction perpendicular to the central axis on the outer surface extending in the direction of the central axis and which are opposed to each other with a gap therebetween, the positioned portion being configured to be engaged with the positioning portion in a state in which the toner container is mounted on the mounting portion, and 
     wherein the positioned portion of the discharge portion is exposed through the rotatable member opening when the rotatable member is in the close position. 
     Structure Example A252 
     A toner container according to any one of Structure Examples A248-A251, wherein the image forming apparatus includes an apparatus side shutter of a cylindrical shape having an open upper part and rotatable about the central axis, the apparatus side shutter being provided with an apparatus side shutter opening in a side surface portion of the apparatus side shutter extending along the central axis, and a projection projecting inward in the radial direction in a region of the apparatus side shutter side surface portion opposed to the apparatus side shutter opening in the radial direction, and 
     wherein in a state in which the toner container is mounted on the mounting portion, 
     the rotatable member is provided, in a rotatable member side surface portion extending along the central axis, with the rotatable member opening which is in fluid communication with the apparatus side shutter opening in the radial direction, and a recess recessed inward in the radial direction and engageable with the projection of the apparatus side shutter. 
     Structure Example A253 
     A toner container according to Structure Example A252, wherein the guided member is disposed at a position closer to the central axis than the projection of the apparatus side shutter side surface portion of the apparatus side shutter in the radial direction, and 
     wherein the projection is closer to the central axis in the radial direction than the recess of the rotatable member, as the toner container is viewed in the direction of the central axis. 
     Structure Example A254 
     A toner container according to Structure Example A252 or A253, wherein the guided member is below the apparatus side shutter opening of the apparatus side shutter in the direction of the central axis, and 
     wherein the projection projects downward with respect to a lower the surface of the toner container, when the toner container is oriented in the predetermined direction. 
     Structure Example A255 
     A toner container according to any one of Structure Examples A246-A254, wherein the projection is configured to project downward from a bottom surface of the discharge portion, when the toner container is oriented in the predetermined direction, and 
     wherein the projection projects downward beyond the bottom surface of the rotatable member through a hole provided in the bottom surface of the rotatable member. 
     Structure Example A256 
     A toner container ( 100 ,  1050 ,  1051 ,  1052 ,  1060 ,  1070 ,  1080 ,  220 ,  2320 ,  23210 ,  2420 ,  2520 ,  2530 ,  2820 ,  520 ,  5120 ,  920 ,  10020 ,  1120 ) mountable to and dismountable from a mounting portion ( 106 ,  206 ) of an image forming apparatus, the mounting portion including a rotatable guided member ( 114 ,  214 ), the toner container comprising: 
     an accommodating ( 101 ,  1015 ,  10151 ,  201 ,  2401 ,  2801 ,  501 ,  901 ) portion configured to accommodate toner; 
     a discharge portion ( 102 ,  1025 ,  202 ,  2302 ,  23102 ,  2402 A,  2502 ,  2503 ,  2802 ,  502 ,  5102 ,  902 ,  1002 A,  1102 ) configured to be provided with an opening ( 102   a ,  202   a ,  2402 Ag,  2502   k   2 ,  2503   k   2 ,  2802   a ,  502   a ,  902 Bk,  10020 Be) for discharging the toner in the accommodating portion to an outside; and 
     a projection ( 102   b ,  1020   b ,  1021   b ,  1023   b ,  1024   b ,  1026   b ,  1027   b ,  1028   b ,  202   b ,  2302   b ,  23102   b ,  2402 Bb,  2502   b ,  2503   b ,  2802   b ,  502   b ,  5102   b ,  903 Bg,  1003   b ,  1132   b ) which includes an inner peripheral surface ( 102   b   1 ,  202   b   1 ,  202   b   10 ) centered on the central axis, which is provided below the opening of the discharge portion, and which projects downward, when the toner container is oriented in a predetermined direction in which the central axis extends in a direction of gravity and at least a part of the discharge portion is below the accommodating portion, 
     wherein the opening of the discharge portion is configured to face outward in a radial direction of an imaginary circle centered on the central axis, and 
     wherein when the toner container is oriented in the predetermined direction, the projection has a downward guide surface ( 104   a   1 ,  104   b   1 ,  1041   b   1 ,  1042   a   1 ,  1043   a   1 ,  1043   b   1 ,  1044   a   1 ,  1046   a   1 ,  1047   a   1 ,  1048   a   1 ,  204   a   1 ,  204   a   2 ,  204   b   1 ,  204   b   2 ,  2304   a   1 ,  2304   b   1 ,  23104   a   1 ,  23104   b   1 ,  2604   b   1 ,  2604   a   2 ) facing downward and an upward guide surface facing upward outside of the inner peripheral surface and inside of the opening of the discharge portion in the radial direction, and an upward guide surface ( 104   a   2 ,  104   b   2 ,  1041   a   2 ,  1042   b   2 ,  1043   a   2 ,  1043   b   2 ,  1044   a   2 ,  1046   a   2 ,  1047   a   2 ,  1048   a   2 ,  204   a   3 ,  204   b   3 ,  2304   a   2 ,  2304   b   2 ,  23104   a   2 ,  23104   b   2 ,  2604   a   3 ) facing upward, 
     when the toner container is moved down in the direction of the central axis toward the mounting portion in a state in which the toner container is oriented in the predetermined direction, 
     the rotational direction of the guided member about the central axis is a first rotational direction, and the rotating direction opposite to the first rotational direction is a second rotational direction, 
     the downward guide surface is configured to guide the guided member so that the guided member rotates in the first rotational direction, and 
     the upward guide surface is configured to guide the guided member so that the guided member moves up after the guided member is rotated in the first rotational direction by the downward guide surface. 
     Structure Example A257 
     A toner container according to any one of Structure Examples A246-A256, wherein the downward guide surface is configured to contact a contacted portion of the guided member to push the guided member so as to rotate the guided member in the first rotational direction, when the toner container is moved down along the central axis toward the mounting portion in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A258 
     A toner container according to Structure Example A257, wherein the downward guide surface extends so as to go up as goes in the first rotational direction. 
     Structure Example A259 
     A toner container according to any one of Structure Examples A246-A258, wherein the upward guide surface is configured to guide the guided member so as to move the guided member up while it is rotated in the second rotational direction. 
     Structure Example A260 
     A toner container according to any one of Structure Examples A246-A258, wherein the image forming apparatus includes an urging member for urging the guided member in the direction in which the guided member rotates in the second rotational direction, 
     wherein the upward guide surface is configured to guide the guided member so that the guided member is moved up while being rotated in the second rotational direction by an urging force of the urging member. 
     Structure Example A261 
     A toner container according to Structure Example A259 or A260, wherein the upward guide surface extends so as to go up as goes in the second rotational direction. 
     Structure Example A262 
     A toner container according to any one of Structure Examples A246-A261, wherein the guided member has a contact surface which is a downstream end surface in the second rotational direction, and 
     wherein the projection includes a contacted surface configured to stop rotation of the guided member in the second rotational direction by contacting the contact surface of the guided member rotated in the second rotational direction while being guided by the upward guide surface. 
     Structure Example A263 
     A toner container according to Structure Example A262, wherein when the toner container is oriented in the predetermined direction, the contacted surface extends upward from a downstream end of the upward guide surface in the second rotational direction along the direction of the central axis and faces downstream side in the second rotational direction. 
     Structure Example A264 
     A toner container according to Structure Example A262 or A263, wherein when the toner container is oriented in the predetermined direction, a cavity is provided right above the upward guide surface of the projection, wherein a portion of the guided member provided with the contact surface is capable of entering the cavity, when the contact surface of the guided member contacts the contacted surface. 
     Structure Example A265 
     A toner container according to any one of Structure Examples A246-A264, comprising a connecting portion, 
     wherein when the toner container is oriented in the predetermined direction, the connecting portion connects the downstream end of the downward guide surface in the first rotational direction and an upstream end of the upward guide surface in the second rotational direction with each other, the connecting portion being configured to guide the guided member so as to switch the rotational direction of the guided member from the first rotational direction to the second rotational direction. 
     Structure Example A266 
     A toner container according to any one of Structure Examples A246-A265, wherein the downward guide surface includes a first downward guide surface and a second downward guide surface which face downward, 
     wherein when the toner container is moved down in the direction of the central axis toward the mounting portion in a state in which the toner container is oriented in the predetermined direction, 
     the first downward guide surface guides the guided member so that the guided member is rotated in the first rotational direction, and 
     the second downward guide surface guides the guided member so that the guided member further is rotated in the first rotational direction after the guided member is guided by the first downward guide surface to be rotated in the first rotational direction. 
     Structure Example A267 
     A toner container according to Structure Example A266, wherein the guided member includes a first contacted portion and a second contacted portion which is provided at a position more away from the central axis in the radial direction than the first contacted portion is, 
     wherein the first downward guide surface is configured to push the first contacted portion to rotate the guided member in the first rotational direction by contacting the first contacted portion, 
     wherein the second downward guide surface is configured to push the second contacted portion to further rotate the guided member in the first rotational direction by contacting the second contacted portion after the guided member is rotated by the first downward guide surface in the first rotational direction. 
     Structure Example A268 
     A toner container according to Structure Example A266 or A267, wherein at least a part of the first downward guide surface is provided at a position which is closer to the central axis in the radial direction than the second downward guide surface is and which is different from the second downward guide surface in a circumferential direction of the imaginary circle. 
     Structure Example A269 
     A toner container according to Structure Example A267, comprising a connecting portion, 
     wherein when the toner container is oriented in the predetermined direction, 
     the connecting portion connects a downstream end of the second downward guide surface in the first rotational direction and an upstream end of the upward guide surface in the second rotational direction with each other, the connecting portion being configured to guide the second contacted portion of the guided member so as to switch the rotational direction of the guided member from the first rotational direction to the second rotational direction. 
     Structure Example A270 
     A toner container according to any one of Structure Examples A246-A269, wherein the guided member includes a first engaging claw extending upward and a second engaging claw which extends upward and which is provided at a position different from a position at which the first engaging claw is provided in a circumferential direction of the imaginary circle, and 
     wherein the projection includes a first projection configured to engage with the first engaging claw and a second projection configured to engage with the second engaging claw, when the toner container is moved down along the central axis relative to the image forming apparatus in a state in which the toner container is oriented in the predetermined direction, 
     the first projection has the upward guide surface, 
     the second projection has the downward guide surface, and 
     the second projection has a 150-210 degree inclusive rotation symmetry shape of the first projection about the central axis. 
     Structure Example A271 
     A toner container according to any one of Structure Examples A266-A269, wherein the guided member includes a first engaging claw extending upward, and a second engaging claw which extends upward and which is provided at a position different from a position at which the first engaging claw is provided in a circumferential direction of the imaginary circle, 
     wherein the projection includes a first projection configured to engage with the first engaging claw and a second projection configured to engage with the second engaging claw, when the toner container is moved down along the central axis relative to the image forming apparatus in a state in which the toner container is oriented in the predetermined direction, and 
     wherein the upward guide surface is a first upward guide surface, 
     the first projection has the first upward guide surface, the first downward guide surface and the second downward guide surface, 
     the second projection has a second upward guide surface, a third downward guide surface and a fourth downward guide surface, and 
     the second upward guide surface, the third downward guide surface and the fourth downward guide surface have shapes of 150-210 degree inclusive rotational symmetry, about the central axis, of the first upward guide surface, the first downward guide surface and the second downward surface, respectively. 
     Structure Example A272 
     A toner container according to Structure Example A271, wherein the second upward guide surface, the third downward guide surface and a fourth downward surface have shapes of 180 degree rotational symmetry, about the central axis, of the first upward guide surface, the first downward guide surface and the second downward surface, respectively. 
     Structure Example A273 
     A toner container according to any one of Structure Examples A246-A272, wherein the image forming apparatus includes a shaft portion extending upward along the central axis and supporting the guided member so as to be rotatable about the central axis, 
     wherein the inner peripheral surface of the projection is configured to engage with the shaft portion when the toner container is moved down along the central axis relative to the image forming apparatus in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A274 
     A toner container according to Structure Example A273, wherein the inner peripheral surface of the projection is cylindrical. 
     Structure Example A275 
     A toner container according to Structure Example A273, wherein the inner peripheral surface of the projection is constituted by a plurality of flat surfaces surrounding the central axis. 
     Structure Example A276 
     A toner container according to any one of Structure Examples A246-A275, wherein as the discharge portion is viewed in the direction of the central axis, the downward guide surface and the upward guide surface are provided at positions closer to the inner peripheral surface in the radial direction than to the opening. 
     Structure Example A277 
     A toner container according to Structure Example A276, wherein as the discharge portion is viewed in the direction of the central axis, a distance from the inner peripheral surface to the upward guide surface and a distance from the inner peripheral surface to the upward guide surface are not more than 30% a distance from the inner peripheral surface to the opening. 
     Structure Example A278 
     An image forming system ( 1000 ) comprising a toner container ( 100 ,  1050 ,  1051 ,  1052 ,  1060 ,  1070 ,  1080 ,  220 ,  2320 ,  23210 ,  2420 ,  2520 ,  2530 ,  520 ,  5120 ,  920 ,  10020 ,  1120 ) and an image forming apparatus ( 1 ) to which the toner container is detachably mountable, 
     wherein the image forming apparatus includes a mounting portion ( 106 ,  206 ) to which the toner container is detachably mountable and which is provided with a rotatable guided member ( 114 ,  214 ), and 
     wherein the toner container includes, 
     an accommodating portion ( 101 ,  1015 ,  10151 ,  201 ,  2401 ,  501 ,  901 ) configured to accommodate toner, 
     a discharge portion ( 102 ,  1025 ,  202 ,  2302 ,  23102 ,  2402 A,  2502 ,  2503 ,  502 ,  5102 ,  902 ,  1002 A,  1102 ) configured to be provided with an opening ( 102   a ,  202   a ,  2402 Ag,  2502   k   2 ,  2503   k   2 ,  502   a ,  902 Bk,  10020 Be) for discharging the toner in the accommodating portion to an outside; 
     a rotatable member ( 103 ,  203 ,  903 A,  1003 ) rotatable relative to the discharge portion about a central axis as a rotational axis, in a first rotational direction about the central axis and a second rotational direction opposed to the first rotational direction, and 
     a projection ( 102   b ,  1020   b ,  1021   b ,  1023   b ,  1024   b ,  1026   b ,  1027   b ,  1028   b ,  202   b ,  2302   b ,  23102   b ,  2402 Bb,  2502   b ,  2503   b ,  502   b ,  5102   b ,  903 Bg,  1003   b ,  1132   b ) provided below the opening of the discharge portion and having inner peripheral surface ( 102   b   1 ,  202   b   1 ,  202   b   10 ) facing inward in a radial direction of an imaginary circle centered on the central axis, when the toner container is oriented in a predetermined direction in which the central axis extends in a direction of gravity and at least a part of the discharge portion is below the accommodating portion, 
     wherein the opening of the discharge portion is configured to face outward in the radial direction, 
     wherein when the toner container is oriented in the predetermined direction, 
     the projection has a downward guide surface ( 104   a   1 ,  104   b   1 ,  1041   b   1 ,  1042   a   1 ,  1043   a   1 ,  1043   b   1 ,  1044   a   1 ,  1046   a   1 ,  1047   a   1 ,  1048   a   1 ,  204   a   1 ,  204   a   2 ,  204   b   1 ,  204   b   2 ,  2304   a   1 ,  2304   b   1 ,  23104   a   1 ,  23104   b   1 ,  2604   b   1 ,  2604   a   2 ) facing downward and an upward guide surface facing upward outside of the inner peripheral surface and inside of the opening of the discharge portion in the radial direction, and an upward guide surface ( 104   a   2 ,  104   b   2 ,  1041   a   2 ,  1042   b   2 ,  1043   a   2 ,  1043   b   2 ,  1044   a   2 ,  1046   a   2 ,  1047   a   2 ,  1048   a   2 ,  204   a   3 ,  204   b   3 ,  2304   a   2 ,  2304   b   2 ,  23104   a   2 ,  23104   b   2 ,  2604   a   3 ) facing upward, 
     when the toner container is moved down along the central axis toward the mounting portion in a state in which the toner container is oriented in the predetermined direction, 
     the downward guide surface is configured to guide the guided member so that the guided member is rotated about the central axis in the first rotational direction, and 
     the upward guide surface is configured to guide the guided member so that the guided member is moved up after the guided member is rotated in the first rotational direction by the downward guide surface. 
     Structure Example A279 
     An image forming system according to Structure Example A278, wherein the rotatable member is provided outside the discharge portion in the radial direction. 
     Structure Example A280 
     An image forming system according to Structure Example A278 or A279, wherein the rotatable member is configured to be rotatable about the central axis between a close position for closing the opening and an open position for opening the opening, the rotatable member being provided with a rotatable member opening for exposing the opening of the discharge portion to an outside of the toner container. 
     Structure Example A281 
     An image forming system according to Structure Example A280, wherein a rotational direction of the rotatable member from the close position toward the open position is the first rotational direction. 
     Structure Example A282 
     An image forming system according to Structure Example A280 or A281, further comprising a seal for sealing between the rotatable member and the discharge portion when the rotatable member is in the close position. 
     Structure Example A283 
     An image forming system according to Structure Example A281 or A282, wherein the mounting portion includes a positioning portion projecting inward in the radial direction, and the discharge portion includes a positioned portion having a first opposing surface and a second opposing surface which extend in a direction perpendicular to the central axis on the outer surface extending in the direction of the central axis and which are opposed to each other with a gap therebetween, the positioned portion being configured to be engaged with the positioning portion in a state in which the toner container is mounted on the mounting portion, positioned portion, and wherein the positioned portion of the discharge portion is exposed through the rotatable member opening when the rotatable member is in the close position. 
     Structure Example A284 
     An image forming system according to any one of Structure Examples A280-A283, wherein the image forming apparatus includes an apparatus side shutter of a cylindrical shape having an open upper part and rotatable about the central axis, the apparatus side shutter being provided with an apparatus side shutter opening in a side surface portion of the apparatus side shutter extending along the central axis, and a projection projecting inward in the radial direction in a region of the apparatus side shutter side surface portion opposed to the apparatus side shutter opening in the radial direction, and 
     wherein in a state in which the toner container is mounted on the mounting portion, 
     the rotatable member is provided, in a rotatable member side surface portion extending along the central axis, with the rotatable member opening which is in fluid communication with the apparatus side shutter opening in the radial direction, and a recess recessed inward in the radial direction and engageable with the projection of the apparatus side shutter. 
     Structure Example A285 
     An image forming system according to Structure Example A284, wherein the guided member is disposed at a position closer to the central axis than the projection of the apparatus side shutter side surface portion of the apparatus side shutter in the radial direction is, and 
     wherein the projection is closer to the central axis in the radial direction than the recess of the rotatable member is, as in the toner container is viewed in the direction of the central axis. 
     Structure Example A286 
     An image forming system according to Structure Example A284 or A285, wherein the guided member is below the apparatus side shutter opening of the apparatus side shutter in the direction of the central axis, and 
     wherein the projection projects downward with respect to a lower the surface of the toner container, when the toner container is oriented in the predetermined direction. 
     Structure Example A287 
     An image forming system according to Structure Example A286, wherein the projection is configured to project downward from a bottom surface of the discharge portion, when the toner container is oriented in the predetermined direction, and 
     wherein the projection projects downward beyond the bottom surface of the rotatable member through a hole provided in the bottom surface of the rotatable member. 
     Structure Example A288 
     An image forming system ( 1000 ) comprising a toner container ( 100 ,  1050 ,  1051 ,  1052 ,  1060 ,  1070 ,  1080 ,  220 ,  2320 ,  23210 ,  2420 ,  2520 ,  2530 ,  2820 ,  520 ,  5120 ,  920 ,  10020 ,  1120 ), and an image forming apparatus ( 1 ) to which the toner container is mountable, 
     wherein the toner container includes, 
     an accommodating portion ( 101 ,  1015 ,  10151 ,  201 ,  2401 ,  2801 ,  501 ,  901 ) configured to accommodate toner, 
     a discharge portion ( 102 ,  1025 ,  202 ,  2302 ,  23102 ,  2402 A,  2502 ,  2503 ,  2802 ,  502 ,  5102 ,  902 ,  1002 A,  1102 ) configured to be provided with an opening ( 102   a ,  202   a ,  2402 Ag,  2502   k   2 ,  2503   k   2 ,  2802   a ,  502   a ,  902 Bk,  10020 Be) for discharging the toner in the accommodating portion to an outside, and 
     a projection ( 102   b ,  1020   b ,  1021   b ,  1023   b ,  1024   b ,  1026   b ,  1027   b ,  1028   b ,  202   b ,  2302   b ,  23102   b ,  2402 Bb,  2502   b ,  2503   b ,  2802   b ,  502   b ,  5102   b ,  903 Bg,  1003   b ,  1132   b ) which includes an inner peripheral surface ( 102   b   1 ,  202   b   1 ,  202   b   10 ) centered on the central axis, which is provided below the opening of the discharge portion, and which projects downward, when the toner container is oriented in a predetermined direction in which the central axis extends in a direction of gravity and at least a part of the discharge portion is below the accommodating portion, 
     wherein the discharge portion is configured to face outward in a radial direction of an imaginary circle centered on the central axis, and 
     wherein when the toner container is oriented in the predetermined direction, the projection has a downward guide surface ( 104   a   1 ,  104   b   1 ,  1041   b   1 ,  1042   a   1 ,  1043   a   1 ,  1043   b   1 ,  1044   a   1 ,  1046   a   1 ,  1047   a   1 ,  1048   a   1 ,  204   a   1 ,  204   a   2 ,  204   b   1 ,  204   b   2 ,  2304   a   1 ,  2304   b   1 ,  23104   a   1 ,  23104   b   1 ,  2604   b   1 ,  2604   a   2 ) facing downward outside of the inner peripheral surface and inside of the opening of the discharge portion in the radial direction, and an upward guide surface ( 104   a   2 ,  104   b   2 ,  1041   a   2 ,  1042   b   2 ,  1043   a   2 ,  1043   b   2 ,  1044   a   2 ,  1046   a   2 ,  1047   a   2 ,  1048   a   2 ,  204   a   3 ,  204   b   3 ,  2304   a   2 ,  2304   b   2 ,  23104   a   2 ,  23104   b   2 ,  2604   a   3 ) facing upward, and 
     wherein the image forming apparatus includes a mounting portion to which the toner container is mountable and which is provided with a rotatable guided member ( 114 ,  214 ), 
     wherein when the toner container is moved down along the central axis toward the mounting portion in a state in which the toner container is oriented in the predetermined direction, 
     the downward guide surface is configured to guide the guided member so that the guided member is rotated in the first rotational about the central axis, and 
     the upward guide surface is configured to guide the guided member so that the guided member is moved up after the guided member is rotated in the first rotational direction by the downward guide surface. 
     Structure Example A289 
     An image forming system according to any one of Structure Examples A278-A288, wherein the downward guide surface is configured to contact a contacted portion of the guided member to push the guided member so as to rotate the guided member in the first rotational direction, when the toner container is moved down along the central axis toward the mounting portion in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A290 
     An image forming system according to Structure Example A289, wherein the downward guide surface extends so as to go up as goes in the first rotational direction. 
     Structure Example A291 
     An image forming system according to any one of Structure Examples A278-A290, wherein the upward guide surface is configured to guide the guided member so that the guided member is moved up while it is rotated in the second rotational direction. 
     Structure Example A292 
     An image forming system according to any one of Structure Examples A278-A290, wherein the image forming apparatus includes an urging member for urging the guided member in a direction of rotating the guided member in a second rotational direction opposite to the first rotational direction, and 
     wherein the upward guide surface is configured to guide the guided member so that the guided member is moved up while being rotated in the second rotational direction by an urging force of the urging member. 
     Structure Example A293 
     An image forming system according to Structure Example A291 or A292, wherein the upward guide surface extends so as to go up as goes in the second rotational direction. 
     Structure Example A294 
     An image forming system according to any one of Structure Examples A278-A293, wherein the guided member has a contact surface which is a downstream end surface in the second rotational direction opposite to the first rotational direction, and 
     wherein the projection includes a contacted surface configured to stop rotation of the guided member in the second rotational direction by contacting the contact surface of the guided member rotated in the second rotational direction while being guided by the upward guide surface. 
     Structure Example A295 
     An image forming system according to Structure Example A294, wherein when the toner container is oriented in the predetermined direction, the contacted surface extends upward from a downstream end of the upward guide surface in the second rotational direction along the direction of the central axis and faces downstream side in the second rotational direction. 
     Structure Example A296 
     An image forming system according to Structure Example A262 or A263, wherein when the toner container is oriented in the predetermined direction, a cavity is provided right above the upward guide surface of the projection, a portion of the guided member provided with the contact surface is capable of entering the cavity, when the contact surface of the guided member contacts the contacted surface. 
     Structure Example A297 
     An image forming system according to any one of Structure Examples A278-A296, comprising a connecting portion, 
     wherein when the toner container is oriented in the predetermined direction, 
     the connecting portion connects the downstream end of the downward guide surface in the first rotational direction and an upstream end of the upward guide surface in the second rotational direction opposite to the first rotational direction with each other, the connecting portion being configured to guide the guided member so as to switch the rotational direction of the guided member from the first rotational direction to the second rotational direction. 
     Structure Example A298 
     An image forming system according to any one of Structure Examples A278-A297, wherein the downward guide surface includes a first downward guide surface and a second downward guide surface which face downward, 
     wherein when the toner container is moved down in the direction of the central axis toward the mounting portion in a state in which the toner container is oriented in the predetermined direction, 
     the first downward guide surface guides the guided member so that the guided member is rotated in the first rotational direction, and 
     the second downward guide surface guides the guided member so that the guided member is further rotated in the first rotational direction after the guided member is guided by the first downward guide surface to rotate in the first rotational direction. 
     Structure Example A299 
     An image forming system according to Structure Example A298, wherein the guided member includes a first contacted portion and a second contacted portion which is provided at a position more away from the central axis in the radial direction than the first contacted portion is, 
     wherein the first downward guide surface is configured to push the first contacted portion to rotate the guided member in the first rotational direction by contacting the first contacted portion, and 
     wherein the second downward guide surface is configured to push the second contacted portion to further rotate the guided member in the first rotational direction by contacting the second contacted portion after the guided member is rotated by the first downward guide surface in the first rotational direction. 
     Structure Example A300 
     An image forming system according to Structure Example A298 or A299, wherein at least a part of the first downward guide surface is configured to be provided at a position which is closer to the central axis in the radial direction than the second downward guide surface is and which is different from at a position at which the second downward guide surface is provided in a circumferential direction of the imaginary circle. 
     Structure Example A301 
     An image forming system according to Structure Example A299, comprising a connecting portion, 
     wherein when the toner container is oriented in the predetermined direction, 
     the connecting portion connects a downstream end of the second downward guide surface in the first rotational direction and an upstream end of the upward guide surface in the second rotational direction with each other, the connecting portion being configured to guide the second contacted portion of the guided member so as to switch the rotational direction of the guided member from the first rotational direction to the second rotational direction. 
     Structure Example A302 
     An image forming system according to any one of Structure Examples A278-A301, wherein the guided member includes a first engaging claw extending upward, and a second engaging claw which extends upward and is provided at a position different from a position at which the first engaging claw is provided in a circumferential direction of the imaginary circle, 
     wherein the projection includes a first projection configured to engage with the first engaging claw, and a second projection configured to engage with the second engaging claw, when the toner container is moved down along the central axis relative to the image forming apparatus in a state in which the toner container is oriented in the predetermined direction, and 
     wherein the first projection has the upward guide surface, and 
     the second projection has the downward guide surface. 
     Structure Example A303 
     An image forming system according to any one of Structure Examples A298-A301, wherein the guided member includes a first engaging claw extending upward, and a second engaging claw which extends upward and is provided at a position different from a position at which the first engaging claw is provided in a circumferential direction of the imaginary circle, 
     wherein the projection includes a first projection configured to engage with the first engaging claw, and a second projection configured to engage with the second engaging claw, when the toner container is moved down along the central axis relative to the image forming apparatus in a state in which the toner container is oriented in the predetermined direction, and 
     wherein when the upward guide surface is a first upward guide surface, 
     the first projection has the first upward guide surface, the first downward guide surface and a second downward surface, 
     the second projection has a second upward guide surface, a third downward guide surface and a fourth downward guide surface, and 
     the second upward guide surface, the third downward guide surface and the fourth downward guide surface have shapes of 150-210 degree inclusive rotational symmetry, about the central axis, of the first upward guide surface, the first downward guide surface and the second downward surface, respectively. 
     Structure Example A304 
     An image forming system according to Structure Example A303, wherein the second upward guide surface, the third downward guide surface and the fourth downward surface have shapes of 180 degree rotational symmetry, about the central axis, of the first upward guide surface, the first downward guide surface and the second downward surface, respectively. 
     Structure Example A305 
     An image forming system according to any one of Structure Examples A278-A304, wherein the image forming apparatus includes a shaft portion extending upward along the central axis and supporting the guided member so that the guided member is rotatable about the central axis, 
     wherein the inner peripheral surface of the projection is configured to engage with the shaft portion when the toner container is moved down along the central axis relative to the image forming apparatus in a state in which the toner container is oriented in the predetermined direction. 
     Structure Example A306 
     An image forming system according to Structure Example A305, wherein the inner peripheral surface of the projection is cylindrical. 
     Structure Example A307 
     An image forming system according to Structure Example A305, wherein the inner peripheral surface of the projection is constituted by a plurality of flat surfaces surrounding the central axis. 
     Structure Example A308 
     An image forming system according to any one of Structure Examples A278-A307, wherein as the discharge portion is viewed in the direction of the central axis, the downward guide surface and the upward guide surface are provided at positions closer to the inner peripheral surface in the radial direction than the opening. 
     Structure Example A309 
     An image forming system according to Structure Example A308, wherein as the discharge portion is viewed in the direction of the central axis, a distance from the inner peripheral surface to the upward guide surface and a distance from the inner peripheral surface to the downward guide surface are not more than 30% a distance from the inner peripheral surface to the opening. 
     Structure Example A310 
     An attachment ( 1090   b ,  2102 A,  21102 A,  2230 ) for being mounted to an image forming apparatus, the attachment comprising: 
     a projection having an inner peripheral surface with a center thereof on a central axis and projecting in a direction of the central axis outside the inner peripheral surface in a radial direction of an imaginary circle having a center on the central axis; 
     wherein when the attachment is oriented in a predetermined direction in which the central axis extends in a direction of gravity and the projection projects downward, 
     the projection has an upward surface, and 
     when a circumferential direction of the imaginary circle is a first circumferential direction, and a direction opposite to the first circumferential direction is a second circumferential direction, the upward surface extends so as to go up as goes in the second circumferential direction. 
     Structure Example A311 
     An attachment ( 1090   b ,  2102 A,  21102 A,  2230 ) for being mounted to an image forming apparatus, the attachment comprising: 
     a projection member ( 2202 ); and 
     a rotatable member ( 2203 ) rotatable about a central axis as a rotational axis relative to the projection member, 
     wherein the projection member has an inner peripheral surface ( 2202   b   1 ) facing inward in a radial direction of an imaginary circle centered on the central axis and a projection ( 2202   b ) projecting in a direction of the central axis outside the inner peripheral surface in the radial direction, 
     wherein when the attachment is oriented in a predetermined direction in which the central axis extends in a direction of gravity and the projection projects downward, 
     the projection member is supported by the rotatable member so that the projection projects downward with respect to a lower surface of the rotatable member, 
     the projection has an upward surface ( 2204   a   3 ), and 
     wherein when a circumferential direction of the imaginary circle is a first circumferential direction, and a direction opposite to the first circumferential direction is a second circumferential direction, the upward surface extends so as to go up as goes in the second circumferential direction. 
     Structure Example A312 
     An attachment according to Structure Example A311, wherein the rotatable member is provided, in an outer surface extending in the direction of the central axis, with a rotatable member opening, and a recess recessed inward in the radial direction, and 
     the recess is provided on a side opposite from the rotatable member opening across the central axis. 
     Structure Example A313 
     An attachment according to Structure Example A312, wherein as the attachment is viewed in the direction of the central axis, the projection is at a position closer to the central axis in the radial direction than to the recess. 
     Structure Example A314 
     An attachment according to Structure Example A312 or A313, wherein the projection is inside a width of the rotation member opening in a direction perpendicular to the central axis, as in viewed in the radial direction. 
     Structure Example A315 
     An attachment according to any one of Structure Examples A310-A314, wherein the upward surface is configured to be exposed to an outside of the attachment. 
     Structure Example A316 
     An attachment according to any one of Structure Examples A310-A315, wherein when the attachment is oriented in the predetermined direction, a cavity is provided above the upward surface of the projection. 
     Structure Example A317 
     An attachment according to any one of Structure Examples A310-A313, wherein when the attachment is oriented in the predetermined direction, the projection has a downstream side end surface which extends upward along the direction of the central axis from a downstream end of the upward surface in the second circumferential direction and which faces downstream side in the first circumferential direction. 
     Structure Example A318 
     An attachment according to any one of Structure Examples A310-A314, wherein when the attachment is viewed in the radial direction in a state in which the attachment is oriented in the predetermined direction, the upward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees. 
     Structure Example A319 
     An attachment according to any one of Structure Examples A310-A318, wherein when the attachment is oriented in the predetermined direction, the projection has a downward surface facing downward and extending so as to go up as goes in the first circumferential direction, and at least a part of the upward surface is above at least a part of the downward surface. 
     Structure Example A320 
     An attachment according to Structure Example A319, wherein the downward surface overlaps the upward surface, as viewed in the direction of the central axis. 
     Structure Example A321 
     An attachment according to Structure Example A319 or A320, wherein the projection includes a connecting portion connecting a downstream end of the downward surface in the first circumferential direction and an upstream end of the upward surface in the second circumferential direction with each other. 
     Structure Example A322 
     An attachment according to any one of Structure Examples A319-A321, wherein when the attachment is viewed in the radial direction in a state in which the attachment is oriented in the predetermined direction, the downward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees. 
     Structure Example A323 
     An attachment according to any one of Structure Examples A319-A322, wherein when the attachment is viewed in the radial direction in a state in which the attachment is oriented in the predetermined direction, the upward surface is longer than the downward surface. 
     Structure Example A324 
     An attachment according to any one of Structure Examples A319-A323, wherein the projection includes a first projection and a second projection which is provided at a position different from a position at which the first position is provided in a circumferential direction of the imaginary circle, 
     wherein the upward surface and the downward surface are a first upward surface and a second downward surface, respectively, 
     wherein the first projection includes the first upward surface and the second downward surface, and 
     wherein the second projection includes a second upward surface and a fourth downward surface. 
     Structure Example A325 
     An attachment according to Structure Example A324, wherein the second upward surface and the fourth downward surface have 150-210 degree inclusive rotational symmetry shapes of the first upward surface and the second downward surface, respectively. 
     Structure Example A326 
     An attachment according to any one of Structure Examples A319-A323, wherein the projection includes a first projection and a second projection which is provided at a position different from a position at which the first projection is provided in the circumferential direction, 
     wherein the first projection includes the upward surface, and 
     wherein the second projection includes the downward surface. 
     Structure Example A327 
     An attachment ( 2102 A,  21102 A,  2230 ) for mounting to an image forming apparatus, the attachment comprising: 
     a projection ( 2102 Ab,  21102 Ab,  2202   b ) having an inner peripheral surface ( 2102 Ab  1 ,  21102 Ab  1 ,  2202   b   1 ) centered on a central axis and projecting in a direction of the central axis outside the inner peripheral surface in a radial direction of an imaginary circle centered on the central axis, 
     wherein when the attachment is oriented in a predetermined direction in which the central axis extends in a direction of gravity and the projection projects downward, 
     the projection has a first downward surface ( 2104   a   1 ,  21104   a   1 ,  2204   a   1 ) and a second downward surface ( 2104   a   2 ,  21104   a   2 ,  2204   a   2 ) which face downward, and an upward surface ( 2104   a   3 ,  21104   a   3 ,  2204   a   3 ) which faces upward, 
     wherein when a circumferential direction of the imaginary circle is a first circumferential direction, and a circumferential direction opposite to the first circumferential direction is a second circumferential direction, the first downward surface and the second downward surface extend so as to go up as go in the first circumferential direction, and at least a part of the first downward surface is at a position which is closer to the central axis in the radial direction than the second downward surface is and which is different from a position at which the second downward surface is provided in the circumferential direction, and 
     at least a part of the upward surface is above at least a part of the second downward surface. 
     Structure Example A328 
     An attachment ( 1090   b ,  2102 A,  21102 A,  2230 ) for being mounted to an image forming apparatus, the attachment comprising: 
     a projection member ( 2202 ); a rotatable member ( 2203 ) rotatable about a central axis as a rotational axis relative to the projection member, 
     wherein the projection member has an inner peripheral surface ( 2202   b   1 ) facing inward in a radial direction of an imaginary circle centered on the central axis and a projection ( 2202   b ) projecting in the direction of the central axis outside the inner peripheral surface in the radial direction, 
     wherein when the attachment is oriented in a predetermined direction in which the central axis extends in a direction of gravity and the projection projects downward, the projection member is supported by the rotatable member so that the projection projects downward with respect to a lower surface of the rotatable member, 
     the projection has a first downward surface ( 2204   a   1 ) and a second downward surface ( 2204   a   2 ) which face downward, and an upward surface ( 2204   a   3 ) which faces upward, 
     when a circumferential direction of the imaginary circle is a first circumferential direction, and a circumferential direction opposite to the first circumferential direction is a second circumferential direction, the first downward surface and the second downward surface extend so as to go up as go in the first circumferential direction, and at least a part of the first downward surface is at a position which is closer to the central axis in the radial direction than the second downward surface is and which is different from a position at which the second downward surface is provided in the circumferential direction, and 
     at least a part of the upward surface is above at least a part of the second downward surface. 
     Structure Example A329 
     An attachment according to Structure Example A328, wherein the rotatable member is provided, in an outer surface extending in the direction of the central axis, with a rotatable member opening, and a recess recessed inward in the radial direction, and 
     wherein the recess is provided on a side opposite from the rotatable member opening across the central axis. 
     Structure Example A330 
     An attachment according to Structure Example A329, wherein as the attachment is viewed in the direction of the central axis, the projection is at a position closer to the central axis in the radial direction than to the recess. 
     Structure Example A331 
     An attachment according to Structure Example A329 or A330, wherein the projection is inside a width of the rotatable member opening in a direction perpendicular to the central axis, as viewed in the radial direction. 
     Structure Example A332 
     An attachment according to any one of Structure Examples A327-A331, wherein when the attachment is oriented in the predetermined direction, the upward surface extends so as to go up as goes in the second circumferential direction. 
     Structure Example A333 
     An attachment according to Structure Example A332, wherein when the attachment is viewed in the radial direction in a state in which the attachment is oriented in the predetermined direction, the upward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees. 
     Structure Example A334 
     An attachment according to any one of Structure Examples A327-A333, wherein the upward surface is configured to be exposed to an outside of the attachment. 
     Structure Example A335 
     An attachment according to any one of Structure Examples A327-A334, wherein when the attachment is oriented in the predetermined direction, a cavity is provided above the upward surface of the projection. 
     Structure Example A336 
     An attachment according to any one of Structure Examples A327-A335, wherein when the attachment is oriented in the predetermined direction, the projection has a downstream side end surface which extends upward along the direction of the central axis from a downstream end of the upward surface in the second circumferential direction and which faces downstream side in the first circumferential direction. 
     Structure Example A337 
     An attachment according to any one of Structure Examples A327-A336, wherein the second downward surface overlaps the upward surface as viewed in the direction of the central axis. 
     Structure Example A338 
     An attachment according to any one of Structure Examples A327-A337, wherein the projection includes a connecting portion connecting a downstream end of the second downward surface in the first circumferential direction and an upstream end of the upward surface in the second circumferential direction with each other. 
     Structure Example A339 
     An attachment according to any one of Structure Examples A327-A338, wherein the projection includes a first projection and a second projection which is provided at a position different from a position at which the first projection is provided in the circumferential direction, 
     wherein the upward surface is a first upward surface, 
     wherein the first projection includes the first upward surface, the first downward surface and the second downward surface, 
     wherein the second projection includes a second upward surface, a third downward surface and a fourth downward surface, 
     wherein when the attachment is oriented in the predetermined direction, 
     the third downward surface and the fourth downward surface extend so as to go up as goes in the first circumferential direction, and at least a part of the third downward surface is at a position which is closer to the central axis in the radial direction than the fourth downward surface is and which is different from a position at which the fourth downward surface is provided in the circumferential direction, and 
     at least a part of the second upward surface is above at least a part of the fourth downward surface. 
     Structure Example A340 
     An attachment according to Structure Example A339, wherein for the first projection, a part of the first downward surface is upstream of the second downward surface in the first circumferential direction, and 
     wherein for the second projection, a part of the third downward surface is upstream of the fourth downward surface in the first circumferential direction. 
     Structure Example A341 
     An attachment according to any one of Structure Examples A327-A338, wherein when the upward surface is a first upward surface, the projection has a third downward surface, a fourth downward surface and a second upward surface having 150-210 degree inclusive rotational symmetrical shapes, about the central axis, of the first downward surface, the second downward surface and the first upward surface, respectively. 
     Structure Example A342 
     An attachment according to any one of Structure Examples A327-A338, wherein when the upward surface is a first upward surface, the projection has a third downward surface, a fourth downward surface and a second upward surface having 180 degree rotational symmetrical shapes, about the central axis, of the first downward surface, the second downward surface and the first upward surface, respectively. 
     Structure Example A343 
     An attachment according to any one of Structure Examples A327-A338, wherein the projection includes a first projection and a second projection which is provided at a position different from a position at which the first projection is provided in the circumferential direction, 
     wherein the first projection has the upward surface and the second downward surface, and 
     wherein the second projection has the first downward surface. 
     Structure Example A344 
     An attachment according to Structure Example A343, wherein the second projection is provided at a position diametrically opposite to the first projection. 
     Structure Example A345 
     An attachment according to any one of Structure Examples A327-A344, wherein when the attachment is viewed in the radial direction in a state in which the attachment is oriented in the predetermined direction, the downward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees. 
     Structure Example A346 
     An attachment according to any one of Structure Examples A327-A345, wherein when the attachment is viewed in the radial direction in a state in which the attachment is oriented in the predetermined direction, the second downward surface inclines with respect to the central axis by an angle not less than 30 degrees and not more than 60 degrees. 
     Structure Example A347 
     An attachment according to any one of Structure Examples A327-A346, wherein when the attachment is viewed in the radial direction in a state in which the attachment is oriented in the predetermined direction, the second downward surface is longer than the first downward surface. 
     Structure Example A348 
     An attachment according to any one of Structure Examples A327-A347, wherein when the attachment is viewed in the radial direction in a state in which the attachment is oriented in the predetermined direction, the upward surface is longer than the first downward surface. 
     Structure Example A349 
     An attachment according to any one of Structure Examples A327-A348, wherein when the attachment is viewed in the radial direction in a state in which the attachment is oriented in the predetermined direction, the upward surface is longer than the second downward surface. 
     Structure Example A350 
     An attachment ( 1090   b ,  2102 A,  21102 A,  2230 ) for being mounting to an image forming apparatus, the attachment comprising: 
     a projection ( 2102 Ab,  21102 Ab,  2202   b ) having an inner peripheral surface ( 2102 Ab  1 ,  21102 Ab  1 ,  2202   b   1 ) centered on a central axis and projecting in a direction of the central axis outside the inner peripheral surface in a radial direction of an imaginary circle centered on the central axis; 
     wherein when the attachment is oriented in a predetermined direction in which the central axis extends in a direction of gravity and the projection projects downward, 
     the projection has a downward guide surface ( 1049   a   1 ,  2104   a   1 ,  2104   a   2 ,  21104   a   1 ,  21104   a   2 ,  2204   a   1 ,  2204   a   2 ) facing downward, and an upward guide surface ( 1049   a   2 ,  2104   a   3 ,  21104   a   3 ,  2204   a   3 ) facing upward, at least a part of the upward guide surface being above at least a part of the downward guide surface. 
     Structure Example A351 
     An attachment ( 2230 ) for being mounted to an image forming apparatus, the attachment comprising: 
     a projection member ( 2202 ); a rotatable member ( 2203 ) rotatable about a central axis as a rotational axis relative to the projection member, 
     wherein the projection member has an inner peripheral surface ( 2202   b   1 ) facing inward in a radial direction of an imaginary circle centered on the central axis and a projection ( 2202   b ) projecting in the direction of the central axis outside the inner peripheral surface in the radial direction, and 
     wherein when the attachment is oriented in a predetermined direction in which the central axis extends in a direction of gravity and the projection projects downward, 
     the projection member is supported by the rotatable member so that the projection projects downward with respect to a lower surface of the rotatable member, 
     the projection has a downward guide surface ( 2204   a   1 ,  2204   a   2 ) facing downward, and an upward guide surface ( 2204   a   3 ) facing upward, at least a part of the upward guide surface being above at least a part of the downward guide. 
     Structure Example A352 
     An attachment according to Structure Example A351, wherein the rotatable member is provided, in an outer surface extending in the direction of the central axis, with a rotatable member opening, and a recess recessed inward in the radial direction, and 
     wherein the recess is provided on a side opposite from the rotatable member opening across the central axis. 
     Structure Example A353 
     An attachment according to Structure Example A352, wherein as the attachment is viewed in the direction of the central axis, the projection is at a position closer to the central axis in the radial direction than to the recess. 
     Structure Example A354 
     An attachment according to Structure Example A352 or A353, wherein the projection is inside a width of the rotation member opening in a direction perpendicular to the central axis, as in viewed in the radial direction. 
     Structure Example A355 
     An attachment according to any one of Structure Examples A350-A354, wherein the downward guide surface is a push surface. 
     Structure Example A356 
     An attachment according to Structure Example A350 or A355, wherein the upward guide surface is configured to be exposed to an outside of the attachment. 
     Structure Example A357 
     An attachment according to any one of Structure Examples A350-A356, wherein when the attachment is oriented in the predetermined direction, a cavity is provided above the upward guide surface of the projection. 
     Structure Example A358 
     An attachment according to any one of Structure Examples A350-A357, wherein when the attachment is oriented in the predetermined direction, 
     a circumferential direction of the imaginary circle is a first circumferential direction, and a circumferential direction opposed to the first circumferential direction is a second circumferential direction, 
     the downward guide surface is configured to extend so as to go up as goes in the first circumferential direction, and 
     the upward guide surface is configured to go up as goes in the second circumferential direction. 
     Structure Example A359 
     An attachment according to Structure Example A358, wherein when the attachment is oriented in the predetermined direction, 
     the projection includes a connecting portion connecting a downstream end of the downward guide surface in the first circumferential direction and an upstream end of the upward guide surface in the second circumferential direction with each other. 
     Structure Example A360 
     An attachment according to Structure Example A358 or A359, wherein when the attachment is oriented in the predetermined direction, the projection has a contacted surface which extends upward in the direction of the central axis from the downstream end of the upward guide surface in the second circumferential direction and which faces a downstream side in the first circumferential direction. 
     Structure Example A361 
     An attachment according to any one of Structure Examples A358-A360, wherein the downward guide surface includes a first downward guide surface and a second downward guide surface which face downward, 
     wherein when the attachment is oriented in the predetermined direction, 
     at least a part of the first downward guide surface is provided at a position different from a position at which the second downward guide surface is provided in the circumferential direction of the imaginary circle. 
     Structure Example A362 
     An attachment according to Structure Example A361, wherein when the attachment is oriented in the predetermined direction, 
     the projection includes a connecting portion connecting a downstream end of the second downward guide surface in the first circumferential direction and an upstream end of the upward guide surface in the second circumferential direction with each other. 
     Structure Example A363 
     An attachment according to Structure Example A361 or A362, wherein the second downward guide surface overlaps the upward guide surface, as is viewed in the direction of the central axis. 
     Structure Example A364 
     An attachment according to any one of Structure Examples A350-A363, wherein the projection includes a first projection and a second projection which is provided at a position different from a position at which the first position is provided in a circumferential direction of the imaginary circle, 
     wherein the first projection has the upward guide surface and the downward guide surface, and 
     wherein the second projection has a 150-210 degree inclusive rotation symmetry shape of the first projection about the central axis. 
     Structure Example A365 
     An attachment according to any one of Structure Examples A350-A363, wherein the projection includes a first projection and a second projection which is provided at a position different from a position at which the first position is provided in a circumferential direction of the imaginary circle, wherein the first projection has the upward guide surface, and wherein the second projection has the downward guide surface. 
     Structure Example A366 
     An attachment according to Structure Example A361, wherein the projection includes a first projection and a second projection which is provided at a position different from a position at which the first projection is provided in a circumferential direction of the imaginary circle, 
     wherein the upward guide surface is a first upward guide surface, 
     the first projection has the first upward guide surface, the first downward guide surface and a second downward surface, and 
     the second projection has a second upward guide surface, a third downward guide surface and a fourth downward guide, and 
     the second upward guide surface, the third downward guide surface and the fourth downward guide surface have shapes of 150-210 degree inclusive rotational symmetry, about the central axis, of the first upward guide surface, the first downward guide surface and the second downward surface, respectively. 
     Structure Example A367 
     An attachment ( 1090   b ,  2102 A,  21102 A,  2230 ) mountable to a mounting portion ( 106 ,  206 ) of an image forming apparatus, the mounting portion including a rotatable guided member ( 114 ,  214 ), the attachment comprising: 
     a projection ( 2102 Ab,  21102 Ab,  2202   b ) having an inner peripheral surface ( 2102 Ab 1 ,  21102 Ab 1 ,  2202   b   1 ) centered on a central axis and projecting in a direction of the central axis outside the inner peripheral surface in a radial direction of an imaginary circle having a center on the central axis; 
     wherein when the attachment is oriented in a predetermined direction in which the central axis extends in a direction of gravity and the projection projects downward, 
     the projection has a downward guide surface ( 1049   a   1 ,  2104   a   1 ,  2104   a   2 ,  21104   a   1 ,  21104   a   2 ,  2204   a   1 ,  2204   a   2 ) facing downward, and an upward guide surface ( 1049   a   2 ,  2104   a   3 ,  21104   a   3 ,  2204   a   3 ) facing upward, at least a part of the upward guide being above at least a part of the downward guide surface, 
     wherein when the attachment is moved downward along the central axis in a state in which the attachment is oriented in the predetermined direction, 
     the projection is configured such that the downward guide surface guides the guided member so that the guided member is rotated in a first rotational direction about the central axis, and such that the upward guide surface guides the guided member so that the guided member is moved upward after the guided member is rotated in the first rotational direction. 
     Structure Example A368 
     An attachment ( 2230 ) mountable to a mounting portion ( 106 ,  206 ) of an image forming apparatus, the mounting portion including a rotatable guided member ( 114 ,  214 ), the attachment comprising: 
     a projection member ( 2202 ); a rotatable member ( 2203 ) rotatable about a central axis as a rotational axis relative to the projection member, 
     wherein the projection member has an inner peripheral surface ( 2202   b   1 ) facing inward in a radial direction of an imaginary circle centered on the central axis and a projection ( 2202   b ) projecting in the direction of the central axis outside the inner peripheral surface in the radial direction, 
     wherein when the attachment is oriented in a predetermined direction in which the central axis extends in a direction of gravity and the projection projects downward, 
     the projection member is supported by the rotatable member so that the projection projects downward with respect to a lower surface of the rotatable member, 
     the projection has a downward guide surface ( 2204   a   1 ,  2204   a   2 ) facing downward, and an upward guide surface ( 2204   a   3 ) facing upward, at least a part of the upward guide surface being above at least a part of the downward guide surface, 
     wherein when the attachment is moved downward along the central axis in a state in which the attachment is oriented in the predetermined direction, 
     the projection is configured such that the downward guide surface guides the guided member so that the guided member is rotated in a first rotational direction about the central axis, and such that the upward guide surface guides the guided member so that the guided member is moved upward after the guided member is rotated in the first rotational direction. 
     Structure Example A369 
     An attachment according to Structure Example A368, wherein the image forming apparatus includes an apparatus side shutter of a cylindrical shape having an open upper part and rotatable about the central axis, the apparatus side shutter being provided with an apparatus side shutter opening in a side surface portion of the apparatus side shutter extending along the central axis, and a projection projecting inward in the radial direction in a region of the apparatus side shutter side surface portion opposed to the apparatus side shutter opening in the radial direction, 
     wherein in a state in which the attachment is mounted on the mounting portion, 
     the rotatable member is provided, in a rotatable member side surface portion extending along the central axis, with the rotatable member opening which is in fluid communication with the apparatus side shutter opening in the radial direction, and a recess recessed inward in the radial direction and engageable with the projection of the apparatus side shutter, 
     Structure Example A370 
     An attachment according to Structure Example 369, wherein the guided member is disposed at a position closer to the central axis than the projection of the apparatus side shutter side surface portion of the apparatus side shutter is in the radial direction, and 
     wherein as the attachment is viewed in the direction of the central axis, the projection is closer to the central axis in the radial direction than to the recess of the rotatable member. 
     Structure Example A371 
     An attachment according to any one of Structure Examples A367-A370, wherein the downward guide surface is configured to contact a contacted portion of the guided member to push the guided member so as to rotate the guided member in the first rotational direction, when the attachment is moved down along the central axis toward the mounting portion in a state in which the attachment is oriented in the predetermined direction. 
     Structure Example A372 
     An attachment according to Structure Example A371, wherein the downward guide surface extends so as to go up as goes in the first rotational direction. 
     Structure Example A373 
     An attachment according to any one of Structure Examples A368-A372, wherein the upward guide surface is configured to guide the guided member so that the guided member is moved up while it is rotated in the second rotational direction. 
     Structure Example A374 
     An attachment according to any one of Structure Examples A368-A372, wherein the image forming apparatus includes an urging member for urging the guided member in a direction of rotating the guided member in a second rotational direction opposite to the first rotational direction, and wherein the upward guide surface is configured to guide the guided member so that the guided member is moved up while being rotated in the second rotational direction by an urging force of the urging member. 
     Structure Example A375 
     An attachment according to Structure Example A373 or A374, wherein the upward guide surface extends so as to go up as goes in the second rotational direction. 
     Structure Example A376 
     An attachment according to Structure Example A367 or A368, wherein the guided member has a contact surface which is a downstream end surface in the second rotational direction opposite to the first rotational direction, and 
     wherein the projection includes a contacted surface configured to stop rotation of the guided member in the second rotational direction by contacting the contact surface of the guided member rotated in the second rotational direction while being guided by the upward guide surface. 
     Structure Example A377 
     An attachment according to Structure Example A376, wherein when the attachment is oriented in the predetermined direction, the contacted surface extends upward from a downstream end of the upward guide surface in the second rotational direction along the direction of the central axis and faces downstream side in the second rotational direction. 
     Structure Example A378 
     An attachment according to Structure Example A376 or A377, wherein when the attachment is oriented in the predetermined direction, a cavity is provided right above the upward guide surface of the projection, wherein a portion of the guided member provided with the contact surface is capable of entering the cavity, when the contact surface of the guided member contacts the contacted surface. 
     Structure Example A379 
     An attachment according to Structure Example A367 or A368, comprising a connecting portion, wherein when the attachment is oriented in the predetermined direction, 
     the connecting portion connects the downstream end of the downward guide surface in the first rotational direction and an upstream end of the upward guide surface in the second rotational direction opposite to the first rotational direction with each other, the connecting portion being configured to guide the guided member so as to switch the rotational direction of the guided member from the first rotational direction to the second rotational direction. 
     Structure Example A380 
     An attachment according to any one of Structure Examples A367-A379, wherein the downward guide surface includes a first downward guide surface and a second downward guide surface which face downward, 
     wherein when the attachment is moved down in the direction of the central axis toward the mounting portion in a state in which the attachment is oriented in the predetermined direction, 
     the first downward guide surface guides the guided member so that the guided member is rotated in the first rotational direction, and 
     the second downward guide surface guides the guided member so that the guided member is further rotated in the first rotational direction after the guided member is guided by the first downward guide surface to be rotated in the first rotational direction. 
     Structure Example A381 
     An attachment according to Structure Example A380, wherein the guided member includes a first contacted portion, and a second contacted portion provided at a position more away from the central axis in the radial direction than the first contacted portion is, 
     wherein the first downward guide surface is configured to push the first contacted portion to rotate the guided member in the first rotational direction by contacting the first contacted portion, 
     wherein the second downward guide surface is configured to push the second contacted portion to further rotate the guided member in the first rotational direction by contacting the second contacted portion after the guided member is rotated by the first downward guide surface in the first rotational direction. 
     Structure Example A382 
     An attachment according to Structure Example A380 or A381, wherein at least a part of the first downward guide surface at a position which is closer to the central axis in the radial direction than the second downward guide surface is and which is different from a position at which the second downward guide surface is provided in a circumferential direction of the imaginary circle. 
     Structure Example A383 
     An attachment according to Structure Example A381, comprising a connecting portion, 
     wherein when the attachment is oriented in the predetermined direction, 
     the connecting portion connects a downstream end of the second downward guide surface in the first rotational direction and an upstream end of the upward guide surface in the second rotational direction opposite to the first rotational direction with each other, the connecting portion being configured to guide the second contacted portion of the guided member so as to switch the rotational direction of the guided member from the first rotational direction to the second rotational direction. 
     Structure Example A384 
     An attachment according to any one of Structure Examples A367-A383, wherein the guided member includes a first engaging claw extending upward, and a second engaging claw which extends upward and is provided at a position different from a position at which the first engaging claw is provided in a circumferential direction of the imaginary circle, 
     wherein the projection includes a first projection configured to engage with the first engaging claw and a second projection configured to engage with the second engaging claw, when the attachment is moved down along the central axis relative to the image forming apparatus in a state in which the attachment is oriented in the predetermined direction, 
     wherein the first projection has the upward guide surface, and 
     wherein the second projection has the downward guide surface. 
     Structure Example A385 
     An attachment according to any one of Structure Examples A380-A383, wherein the guided member includes a first engaging claw extending upward, and a second engaging claw which extends upward and is provided at a position different from a position at which the first engaging claw is provided in a circumferential direction of the imaginary circle, 
     wherein the projection includes a first projection configured to engage with the first engaging claw and a second projection configured to engage with the second engaging claw, when the attachment is moved down along the central axis relative to the image forming apparatus in a state in which the attachment is oriented in the predetermined direction, 
     wherein when the upward guide surface is a first upward guide surface, 
     the first projection has the first upward guide surface, the first downward guide surface and a second downward surface, 
     the second projection has a second upward guide surface, a third downward guide surface and a fourth downward guide surface, and 
     the second upward guide surface, the third downward guide surface and the fourth downward guide surface have shapes of 150-210 degree inclusive rotational symmetry, about the central axis, of the first upward guide surface, the first downward guide surface and the second downward surface, respectively. 
     Structure Example A386 
     An attachment according to Structure Example A385, wherein the second upward guide surface, the third downward guide surface and a fourth downward surface have shapes of 180 degree rotational symmetry, about the central axis, of the first upward guide surface, the first downward guide surface and the second downward surface, respectively. 
     Structure Example A387 
     An attachment according to any one of Structure Examples A367-A386, wherein the image forming apparatus includes a shaft portion extending upward along the central axis and supporting the guided member so as to be rotatable about the central axis, 
     wherein the inner peripheral surface of the projection is configured to engage with the shaft portion when the attachment is moved down along the central axis relative to the image forming apparatus in a state in which the attachment is oriented in the predetermined direction. 
     Structure Example A388 
     An attachment according to Structure Example A387, wherein the inner peripheral surface of the projection is cylindrical. 
     Structure Example A389 
     An attachment according to Structure Example A387, wherein the inner peripheral surface of the projection is constituted by a plurality of flat surfaces surrounding the central axis. 
     Structure Example A390 
     A mounting kit comprising: 
     an accommodating portion configured to accommodate toner; 
     a discharge portion configured to be provided with an opening for discharging the toner in the accommodating portion to an outside, the discharge portion and the accommodating portion being arranged in a first direction, the mounting kit comprising; 
     a toner container configured such that the opening faces in a second direction crossing the first direction; and 
     an attachment according to any one of Structure Examples A313-A389. 
     Structure Example A391 
     A mounting kit according to Structure Example A390, wherein when the toner container is oriented in a predetermined direction in which at least a part of the discharge portion is below the accommodating portion and the first direction is a direction of gravity, 
     the attachment is configured to be attached to a bottom surface of the toner container. 
     Structure Example A392 
     A mounting kit according to Structure Example A390, wherein when the toner container is oriented in a predetermined direction in which at least a part of the discharge portion is below the accommodating portion and the first direction is a direction of gravity, 
     the bottom surface of the toner container is provided with a recess to receive a part of the attachment. 
     Structure Example A393 
     An image forming system ( 1000 ) comprising an image forming apparatus ( 1 ), an attachment ( 1090   b ,  2102 A,  21102 A,  2230 ) mountable to the image forming apparatus, 
     wherein the image forming apparatus includes a mounting portion ( 106 ,  206 ) to which the attachment is mountable, the mounting portion including a rotatable guided member ( 114 ,  214 ), and 
     wherein the attachment has an inner peripheral surface ( 2102 Ab  1 ,  21102 Ab  1 ,  2202   b   1 ) centered on the central axis, the attachment including a projection ( 2102 Ab,  21102 Ab,  2202   b ) projecting in a direction of the central axis outside of the inner peripheral surface in a radial direction of an imaginary circle centered on the central axis, and 
     wherein when the attachment is oriented in a predetermined direction in which the central axis extends in a direction of gravity and the projection projecting downward, 
     the projection has a downward guide surface ( 1049   a   1 ,  2104   a   1 ,  2104   a   2 ,  21104   a   1 ,  21104   a   2 ,  2204   a   1 ,  2204   a   2 ) facing downward, and an upward guide surface ( 1049   a   2 ,  2104   a   3 ,  21104   a   3 ,  2204   a   3 ) facing upward, at least a part of the upward guide surface being above at least a part of the downward guide surface, 
     wherein when the attachment is moved downward along the central axis toward the mounting portion in a state in which the attachment is oriented in the predetermined direction, 
     the downward guide surface is configured to guide the guided member so that the guided member is rotated in the first rotational about the central axis, and the upward guide surface is configured to guide the guided member so that the guided member is moved up after the guided member is rotated in the first rotational direction by the downward guide surface. 
     Structure Example A394 
     An image forming system ( 1000 ) comprising an image forming apparatus ( 1 ), and an attachment ( 2230 ) mountable to the image forming apparatus, 
     wherein the image forming apparatus includes a mounting portion ( 106 ,  206 ) to which the attachment is mountable, the mounting portion including a rotatable guided member ( 114 ,  214 ), and 
     wherein the attachment includes a projection member ( 2202 ), a rotatable member ( 2203 ) rotatable about a central axis as a rotational axis relative to the projection member, 
     wherein the projection member has an inner peripheral surface ( 2202   b   1 ) facing inward in a radial direction of an imaginary circle centered on the central axis and a projection ( 2202   b ) projecting in the direction of the central axis outside the inner peripheral surface in the radial direction, 
     wherein when the attachment is oriented in a predetermined direction in which the central axis extends in a direction of gravity and the projection projects downward, 
     the projection member is supported by the rotatable member so that the projection projects downward with respect to a lower surface of the rotatable member, 
     the projection has a downward guide surface ( 1049   a   1 ,  2104   a   1 ,  2104   a   2 ,  21104   a   1 ,  21104   a   2 ,  2204   a   1 ,  2204   a   2 ) facing downward, and an upward guide surface ( 1049   a   2 ,  2104   a   3 ,  21104   a   3 ,  2204   a   3 ) facing upward, at least a part of the upward guide surface being above at least a part of the downward guide surface, and 
     wherein when the attachment is moved downward along the central axis in a state in which the attachment is oriented in the predetermined direction, 
     the projection is configured such that the downward guide surface guides the guided member so that the guided member is rotated in a first rotational direction about the central axis, and such that the upward guide surface guides the guided member so that the guided member is moved upward after the guided member is rotated in the first rotational direction. 
     Structure Example A395 
     An image forming system according to Structure Example A394, wherein the image forming apparatus includes an apparatus side shutter of a cylindrical shape having an open upper part and rotatable about the central axis, the apparatus side shutter being provided with an apparatus side shutter opening in a side surface portion of the apparatus side shutter extending along the central axis, and a projection projecting inward in the radial direction in a region of the apparatus side shutter side surface portion opposed to the apparatus side shutter opening in the radial direction, 
     wherein in a state in which the attachment is mounted on the mounting portion, 
     the rotatable member is provided, in a rotatable member side surface portion extending along the central axis, with the rotatable member opening which is in fluid communication with the apparatus side shutter opening in the radial direction, and a recess recessed inward in the radial direction and engageable with the projection of the apparatus side shutter. 
     Structure Example A396 
     An image forming system according to Structure Example A395, wherein the guided member is disposed at a position closer to the central axis than the projection of the apparatus side shutter side surface portion of the apparatus side shutter is in the radial direction, and 
     wherein as the attachment is viewed in the direction of the central axis, the projection is closer to the central axis in the radial direction than to the recess of the rotatable member. 
     Structure Example A397 
     An image forming system according to any one of Structure Examples A393-A396, wherein the downward guide surface is configured to contact a contacted portion of the guided member to push the guided member so as to rotate the guided member in the first rotational direction, when the attachment is moved down along the central axis toward the mounting portion in a state in which the attachment is oriented in the predetermined direction. 
     Structure Example A398 
     An image forming system according to Structure Example A397, wherein the downward guide surface extends so as to go up as goes in the first rotational direction. 
     Structure Example A399 
     An image forming system according to any one of Structure Examples A393-A398, wherein the upward guide surface is configured to guide the guided member so that the guided member is moved up while it is rotated in the second rotational direction. 
     Structure Example A400 
     An image forming system according to any one of Structure Examples A393-A398, wherein the image forming apparatus includes an urging member for urging the guided member in a direction of rotating the guided member in a second rotational direction opposite to the first rotational direction, and 
     wherein the upward guide surface is configured to guide the guided member so that the guided member is moved up while being rotated in the second rotational direction by an urging force of the urging member. 
     Structure Example A401 
     An image forming system according to Structure Example A399 or A400, wherein the upward guide surface extends so as to go up as goes in the second rotational direction. 
     Structure Example A402 
     An image forming system according to any one of Structure Examples A393-A401, wherein the guided member has a contact surface which is a downstream end surface in the second rotational direction opposite to the first rotational direction, and 
     wherein the projection includes a contacted surface configured to stop rotation of the guided member in the second rotational direction by contacting the contact surface of the guided member rotated in the second rotational direction while being guided by the upward guide surface. 
     Structure Example A403 
     An image forming system according to Structure Example A402, wherein when the attachment is oriented in the predetermined direction, the contacted surface extends upward from a downstream end of the upward guide surface in the second rotational direction along the direction of the central axis and faces downstream side in the second rotational direction. 
     Structure Example A404 
     An image forming system according to Structure Example A402 or A403, wherein when the attachment is oriented in the predetermined direction, a cavity is provided right above the upward guide surface of the projection, wherein a portion of the guided member provided with the contact surface is capable of enter the cavity, when the contact surface of the guided member contacts the contacted surface. 
     Structure Example A405 
     An image forming system according to any one of Structure Examples A393-A404, comprising a connecting portion, 
     wherein when the attachment is oriented in the predetermined direction, the connecting portion connects the downstream end of the downward guide surface in the first rotational direction and an upstream end of the upward guide surface in the second rotational direction opposite to the first rotational direction with each other, the connecting portion being configured to guide the guided member so as to switch the rotational direction of the guided member from the first rotational direction to the second rotational direction. 
     Structure Example A406 
     An image forming system according to any one of Structure Examples A393-A405, wherein the downward guide surface includes a first downward guide surface and a second downward guide surface which face downward, 
     wherein when the attachment is moved down in the direction of the central axis toward the mounting portion in a state in which the attachment is oriented in the predetermined direction, 
     the first downward guide surface guides the guided member so that the guided member is rotated in the first rotational direction, and 
     the second downward guide surface guides the guided member so that the guided member further is rotated in the first rotational direction after the guided member is guided by the first downward guide surface to be rotated in the first rotational direction. 
     Structure Example A407 
     An image forming system according to Structure Example A406, wherein the guided member includes a first contacted portion and a second contacted portion which is provided at a position more away from the central axis in the radial direction than the first contacted portion is, wherein the first downward guide surface is configured to push the first contacted portion to rotate the guided member in the first rotational direction by contacting the first contacted portion, 
     wherein the second downward guide surface is configured to push the second contacted portion to further rotate the guided member in the first rotational direction by contacting the second contacted portion after the guided member is rotated by the first downward guide surface in the first rotational direction. 
     Structure Example A408 
     An image forming system according to Structure Example A406 or A407, wherein at least a part of the first downward guide surface is provided at a position which is closer to the central axis in the radial direction than the second downward guide surface is and which is different from a position at which the second downward guide surface is provided in a circumferential direction of the imaginary circle. 
     Structure Example A409 
     An image forming system according to Structure Example A407, comprising a connecting portion, 
     wherein when the attachment is oriented in the predetermined direction, the connecting portion connects a downstream end of the second downward guide surface in the first rotational direction and an upstream end of the upward guide surface in the second rotational direction opposite to the first rotational direction with each other, the connecting portion being configured to guide the second contacted portion of the guided member so as to switch the rotational direction of the guided member from the first rotational direction to the second rotational direction. 
     Structure Example A410 
     An image forming system according to any one of Structure Examples A393-A408, wherein the guided member includes a first engaging claw extending upward and a second engaging claw which extends upward which is provided at a position different, in a circumferential direction of the imaginary circle, from at a position at which the first engaging claw is provided, 
     wherein the projection includes a first projection configured to engage with the first engaging claw and a second projection configured to engage with the second engaging claw, when the attachment is moved down along the central axis relative to the image forming apparatus in a state in which the attachment is oriented in the predetermined direction, 
     wherein the first projection has the upward guide surface, 
     wherein the second projection has the downward guide surface. 
     Structure Example A411 
     An image forming system according to any one of Structure Examples A406-A408, wherein the guided member includes a first engaging claw extending upward, and a second engaging claw which extends upward and is provided at a position different, in a circumferential direction of the imaginary circle, from a position at which the first engaging claw is provided, 
     wherein the projection includes a first projection configured to engage with the first engaging claw and a second projection configured to engage with the second engaging claw, when the attachment is moved down along the central axis relative to the image forming apparatus in a state in which the attachment is oriented in the predetermined direction, 
     wherein the upward guide surface is a first upward guide surface, 
     the first projection has the first upward guide surface and the first downward guide surface and a second downward surface, 
     the second projection has a second upward guide surface, a third downward guide surface and a fourth downward guide surface, and 
     the second upward guide surface, the third downward guide surface and the fourth downward guide surface have shapes of 150-210 degree inclusive rotational symmetry, about the central axis, of the first upward guide surface, the first downward guide surface and the second downward surface, respectively. 
     Structure Example A412 
     An image forming system according to Structure Example A411, wherein the second upward guide surface, the third downward guide surface and a fourth downward surface have shapes of 180 degree rotational symmetry, about the central axis, of the first upward guide surface, the first downward guide surface and the second downward surface, respectively. 
     Structure Example A413 
     An image forming system according to any one of Structure Examples A393-A412, wherein the image forming apparatus includes a shaft portion extending upward along the central axis and supporting the guided member so as to be rotatable about the central axis, and 
     wherein the inner peripheral surface of the projection is configured to engage with the shaft portion when the attachment is moved down along the central axis relative to the image forming apparatus in a state in which the attachment is oriented in the predetermined direction. 
     Structure Example A414 
     An image forming system according to Structure Example A413, wherein the inner peripheral surface of the projection is cylindrical. 
     Structure Example A415 
     An image forming system according to Structure Example A413, wherein the inner peripheral surface of the projection is constituted by a plurality of flat surfaces surrounding the central axis. 
     Structure Example A416 
     A method of use of an attachment ( 1090   b ,  2102 A,  21102 A,  2230 ) to be mounted to an image forming apparatus ( 1 ), wherein the image forming apparatus includes a main assembly accommodating portion ( 36 ) for accommodating toner, and a mounting portion ( 106 ,  206 ) for mounting the attachment, 
     the mounting portion including, 
     a frame ( 107 ,  117 ,  207 ,  217 ) provided with a frame opening ( 117   a ,  217   a ) in fluid communication with the main assembly accommodating portion, 
     an apparatus side shutter ( 109 ,  209 ) provided with a rotation restricted portion ( 109   c ,  209   c ) and an apparatus side shutter ( 109   a ,  209   a ), the apparatus side shutter is rotatable about a rotational axis between a non-fluid-communication position in which the apparatus side shutter opening is not in fluid communication with the frame opening and a fluid communication position in which the apparatus side shutter opening is in fluid communication with the frame opening, 
     a restricting member ( 113 ,  213 ) including a rotation restriction portion ( 113   c ,  213   c ) movable in a direction along the rotational axis between a restriction position in which the rotation restriction portion engages with the rotation restricted portion of the apparatus side shutter to restrict rotation of the apparatus side shutter from the non-fluid-communication position to the fluid communication position, and a release position which is above the restriction position and in which restriction against the rotation of the apparatus side shutter from non-fluid-communication position to the fluid communication position is released, 
     a release member ( 114 ,  214 ) including a contacted portion ( 214   e A,  214   e B) and rotatable about the rotational axis in a first rotational direction and a second rotational direction opposite to the first rotational direction, the release member being movable upward with the restricting member so as to move the restricting member from the restriction position to the release position, and 
     an urging member urging the release member in a direction of moving the release member in the second rotational direction, 
     a rise restriction portion ( 110   e ,  210   e ) for restricting upward movement of the release member, 
     wherein the attachment includes a projection ( 2102 Ab,  21102 Ab,  2202   b ) having an inner peripheral surface ( 2102 Ab  1 ,  21102 Ab  1 ,  2202   b   1 ) centered on a central axis, and a projection ( 2102 Ab,  21102 Ab,  2202   b ) projecting in a direction of the central axis outside the inner peripheral surface in a radial direction of an imaginary circle centered on the central axis, 
     wherein when the attachment is oriented in a predetermined direction in which the central axis extends in a direction of gravity and the projection projects downward, the projection has a downward surface ( 1049   a   1 ,  2104   a   1 ,  2104   a   2 ,  21104   a   1 ,  21104   a   2 ,  2204   a   1 ,  2204   a   2 ) facing downward, and an upward surface ( 1049   a   2 ,  2104   a   3 ,  21104   a   3 ,  2204   a   3 ) facing upward, at lease a part of the upward surface being above at lease a part of the downward surface, 
     the method comprising: 
     a first step of moving the attachment downward toward the mounting portion along the central axis in a state in which the attachment is oriented in the predetermined direction to bring the downward surface into contact with the contacted portion of the release member so as to rotate the release member in the first rotational direction against an urging force of the urging member to a rise restriction release region in which upward movement of the release member is not restricted by the rise restriction portion, and 
     a second step of guiding, after the first step, the contacted portion of the release member by the upward surface so as to move the release member upward while being rotated in the second rotational direction by the urging force. 
     Structure Example A417 
     An using method according to Structure Example A416, wherein the apparatus side shutter includes a shaft portion centered on the rotational axis and extending upward along rotational axis, and the inner peripheral surface of the attachment is engaged with the shaft portion of the apparatus side shutter in the first step. 
     Structure Example A418 
     A method of use according to Structure Example A416 or A417, wherein the attachment includes a projection member having the projection, and a rotatable member rotatable relative to the projection member about the central axis, the rotatable member being provided with a recess recessed inward in the radial direction in a rotatable member side surface portion extending along rotational axis, 
     wherein the apparatus side shutter includes a projection projecting inward in the radial direction on an inner peripheral surface of a side surface portion of the apparatus side shutter extending along the rotational axis, and 
     wherein the first step includes engaging the recess of the rotatable member with the projection of the apparatus side shutter. 
     Structure Example A419 
     A method of use according to any one of Structure Examples A416-A418, further comprising a third step of mounting the toner container containing the toner to the mounting portion after the attachment is mounted on the mounting portion. 
     Structure Example A420 
     A method of releasing rotation restriction on a shutter of an image forming apparatus, wherein the image forming apparatus includes a main assembly accommodating portion ( 36 ) for accommodating toner, and a mounting portion ( 106 ,  206 ) for mounting a toner container ( 100 ,  1050 ,  1051 ,  1052 ,  1060 ,  1070 ,  1080 ,  1090 ,  220 ,  2120 ,  2220 ,  2320 ,  23210 ,  2420 ,  2520 ,  2530 ,  2820 ,  320 ,  3220 ,  520 ,  5120 ,  620 ,  720 ,  7120 ,  7220 ,  7320 ,  820 ,  920 ,  10020 ,  1120 ), 
     wherein the mounting portion includes, 
     a frame ( 107 ,  117 ,  207 ,  217 ) provided with a frame opening ( 117   a ,  217   a ) in fluid communication with the main assembly accommodating portion, 
     a shutter ( 109 ,  209 ) provided with a rotation restricted portion ( 109   c ,  209   c ) and a shutter opening ( 109   a ,  209   a ) and rotatable about a rotational axis between a non-fluid-communication position in which the shutter opening is not in fluid communication with the frame opening and a fluid communication position in which the shutter opening is in fluid communication with the frame opening, 
     a restricting member ( 113 ,  213 ) including a rotation restriction portion ( 113   c ,  213   c ) including a rotation restriction portion ( 113   c ,  213   c ) movable in a direction along the rotational axis between a restriction position in which the rotation restriction portion engages with the rotation restricted portion of the shutter to restrict rotation of the apparatus side shutter from the non-fluid-communication position to the fluid communication position, and a release position which is above the restriction position and in which restriction against the rotation of the apparatus side shutter from non-fluid-communication position to the fluid communication position is released, 
     a release member ( 114 ,  214 ) rotatable about the rotational axis in a first rotational direction and a second rotational direction opposite to the first rotational direction, the release member being movable upward along the rotational axis with the restricting member so as to move the restricting member from the restriction position to the release position, 
     an urging member ( 116 ,  216 ) urging the release member in a direction of moving the release member in the second rotational direction, 
     a rise restriction portion ( 110   e ,  210   e ) for restricting upward movement of the release member, 
     the method comprising: 
     a first step of rotating the release member in the first rotational direction against an urging force of the urging member to a rise restriction release region in which upward movement of the release member is not restricted by the rise restriction portion, and 
     a second step of moving, after the first step, the release member upward so that the restricting member is moved together from the restriction position to the release position. 
     Structure Example A421 
     An image forming system ( 1000 ) comprising a toner container ( 100 ,  1050 ,  1051 ,  1052 ,  1060 ,  1070 ,  1080 ,  220 ,  2320 ,  23210 ,  2420 ,  2520 ,  2530 ,  2820 ,  420 ,  520 ,  5120 ,  920 ,  10020 ,  1120 ) and an image forming apparatus ( 1 ) to which the toner container is mountable, 
     wherein the toner container includes, 
     a first accommodating portion ( 101 ,  1015 ,  10151 ,  201 ,  2401 ,  2801 ,  501 ,  901 ) configured to accommodate toner, 
     a discharge portion ( 102 ,  1025 ,  202 ,  2302 ,  23102 ,  2402 A,  2502 ,  2503 ,  2802 ,  402 ,  430 ,  502 ,  5102 ,  902 ,  1002 A,  1102 ) provided with an opening ( 102   a ,  202   a ,  2402 Ag,  2502   k   2 ,  2503   k   2 ,  2802   a ,  430   a ,  502   a ,  902 Bk,  10020 Be) for discharging the toner in the first accommodating portion to an outside of the toner container, and 
     wherein when the toner container is oriented in a predetermined direction in which the central axis extends in a direction of gravity and at least a part of the discharge portion is below the accommodating portion, the toner container further includes an inner peripheral surface ( 102   b   1 ,  202   b   1 ,  202   b   10 ) centered on a central axis, and a projection ( 102   b ,  1020   b ,  1021   b ,  1023   b ,  1024   b ,  1026   b ,  1027   b ,  1028   b ,  202   b ,  2302   b ,  23102   b ,  2402 Bb,  2502   b ,  2503   b ,  2802   b ,  402   b ,  502   b ,  5102   b ,  903 Bg,  1003   b ,  1132   b ) projecting downward below the opening of the discharge portion, the projection including an upward surface ( 104   a   2 ,  104   b   2 ,  1041   a   2 ,  1042   b   2 ,  1043   a   2 ,  1043   b   2 ,  1044   a   2 ,  1046   a   2 ,  1047   a   2 ,  1048   a   2 ,  204   a   3 ,  204   b   3 ,  2304   a   2 ,  2304   b   2 ,  23104   a   2 ,  23104   b   2 ,  2604   a   3 ) facing upward, and a downward surface ( 104   a   1 ,  104   b   1 ,  1041   b   1 ,  1042   a   1 ,  1043   a   1 ,  1043   b   1 ,  1044   a   1 ,  1046   a   1 ,  1047   a   1 ,  1048   a   1 ,  204   a   1 ,  204   a   2 ,  204   b   1 ,  204   b   2 ,  2304   a   1 ,  2304   b   1 ,  23104   a   1 ,  23104   b   1 ,  2604   b   1 ,  2604   a   2 ) facing downward, which are provided outside the inner peripheral surface and inside the opening of the discharge portion in a radial direction of an imaginary circle centered on the central axis, and 
     wherein the image forming apparatus includes, 
     a photosensitive drum ( 21 ), 
     a developing roller ( 31 ) for supplying the toner to the photosensitive drum, 
     a second accommodating portion ( 36 ) configured to accommodate the toner supplied from the toner container, 
     a mounting portion ( 106 ,  206 ) to which the toner container is mountable, 
     wherein the mounting portion includes, 
     a frame ( 107 ,  117 ,  207 ,  217 ) provided with a frame opening ( 117   a ,  217   a ) in fluid communication with the second accommodating portion, 
     an apparatus side shutter provided with a rotation restricted portion ( 109   c ,  209   c ) and an apparatus side shutter opening ( 109   a ,  209   a ) and rotatable about a rotational axis between a fluid communication position in which the apparatus side shutter opening is in fluid communication with the frame opening and a non-fluid-communication position in which the apparatus side shutter opening is not in fluid communication with the frame opening, the apparatus side shutter being further provided with a shaft portion ( 109   d ,  209   d ) centered on the rotational axis and extending in a direction of the rotational axis, 
     a restricting member ( 113 ,  213 ) including a rotation restriction portion ( 113   c ,  213   c ) movable in a direction along the rotational axis between a restriction position in which the rotation restriction portion engages with the rotation restricted portion of the apparatus side shutter to restrict rotation of the apparatus side shutter from the non-fluid-communication position to the fluid communication position, and a release position which is above the restriction position and in which restriction against the rotation of the apparatus side shutter from non-fluid-communication position to the fluid communication position is released, 
     a release member ( 114 ,  214 ) including a contacted portion ( 214   e A,  214   e B) and supported by the shaft portion of the apparatus side shutter so as to be rotatable about the rotational axis in a first rotational direction and a second rotational direction opposite to the first rotational direction, the release member being movable upward with the restricting member so as to move the restricting member from the restriction position to the release position, 
     an urging member ( 116 ,  216 ) urging the release member in a direction of moving the release member in the second rotational direction, 
     a rise restriction portion ( 110   e ,  210   e ) for restricting upward movement of the release member, 
     wherein when the toner container is moved down toward the mounting portion in a state in which the toner container is oriented in the predetermined direction, 
     the inner peripheral surface of the projection is engaged with the shaft portion of the apparatus side shutter, 
     the release member is rotated in the first rotational direction against an urging force of the urging member to a rise restriction release region in which upward movement of the release member is not restricted by the rise restriction portion, and 
     the upward surface guides the contacted portion of the release member so that after the release member is rotated in the first rotational direction by the downward surface, the release member is moved up while being rotated in the second rotational direction by the urging force, by which the restricting member is moved from the restriction position to the release position by the release member. 
     Structure Example A422 
     An image forming system according to Structure Example A421, wherein the downward surface includes a first downward surface and a second downward surface which is provided at a position more away from the rotational axis in the radial direction than the first downward surface is, 
     wherein the contacted portion includes a first contacted portion and a second contacted portion which is provided at a position more away from the rotational axis in the radial direction than the first contacted portion is, 
     wherein after the first downward surface contacts with the first contacted portion to rotate the release member in the first rotational direction against the urging force, the second downward surface contacts the second contacted portion to rotate the release member further in the first rotational direction, and thereafter, the upward surface guides the second contacted portion so that the release member is moved upward while being rotated in the second rotational direction by the urging force of the urging member. 
     Structure Example A423 
     An image forming system according to Structure Example A422, wherein the image forming apparatus includes a cover covering an upper part of the release member, the cover being provided with a cover opening in a top surface thereof, 
     wherein as the mounting portion is viewed in a direction of the rotational axis in a state in which the toner container is not mounted on the mounting portion, the first contacted portion is exposed through the cover opening, and the second contacted portion is covered by the cover, 
     wherein as the mounting portion is viewed in the direction of the central axis, the second contacted portion is exposed through the cover opening by the first downward surface contacting with the first contacted portion to rotate the release member in the first rotational direction, and 
     wherein in a state in which the second contacted portion is exposed through the cover opening, the release member is further rotated in the first rotational direction by the second downward surface contacting with the second contacted portion. 
     Structure Example A424 
     An image forming system according to any one of Structure Examples A421-A423, wherein the toner container includes a rotatable member rotatable, about a central axis as a rotational axis relative to the discharge portion, in a first rotational direction and in a second rotational direction opposite to the first rotational direction, the rotatable member including a push portion, 
     wherein the apparatus side shutter of the mounting portion is provided with a pushed portion engaged with the push portion when the toner container is mounted to the mounting portion, 
     wherein when the rotatable member is rotated, the pushed portion of the apparatus side shutter is pushed by the push portion of the rotatable member to rotate the apparatus side shutter from the non-fluid-communication position to the fluid communication position. 
     Structure Example B1 
     A toner container mountable to and dismountable from an image forming apparatus, the image forming apparatus including a release member ( 114 ,  214 ) for releasing rotation restriction of an apparatus side shutter which is rotatable for fluid communication with a toner receiving opening ( 117   a ,  217   a ), the release member rotatable about a rotational axis in a first rotational direction and a second rotational direction opposite to the first rotational direction and movable upward, the toner container comprising: 
     an accommodating portion configured to accommodate toner ( 101 ,  1015 ,  10151 ,  201 ,  2401 ,  2801 ,  501 ,  901 ); 
     a discharge portion ( 102 ,  1025 ,  202 ,  2302 ,  23102 ,  2402 A,  2502 ,  2503 ,  2802 ,  302 ,  502 ,  5102 ,  902 ,  1002 A,  1102 ) configured to be provided with an opening ( 102   a ,  202   a ,  2402 Ag,  2502   k   2 ,  2503   k   2 ,  2802   a ,  302   a ,  502   a ,  902 Bk,  10020 Be) for discharging the toner in the accommodating portion to the receiving opening; and 
     an engaging portion ( 202   b ,  2302   b ,  23102   b ,  2402 Bb,  2502   b ,  2503   b ,  2802   b ,  304 ,  3104 ,  3204 ,  502   b ,  5102   b ,  604 ,  804 ,  8104 ,  8204 ,  8304 ,  903 Bg,  1003   b ,  1132   b ) having a first engagement surface and a second engagement surface, 
     wherein the first engagement surface ( 104   a   1 ,  104   b   1 ,  1041   b   1 ,  1042   a   1 ,  1043   a   1 ,  1043   b   1 ,  1044   a   1 ,  1046   a   1 ,  1047   a   1 ,  1048   a   1 ,  204   a   1 ,  204   a   2 ,  204   b   1 ,  204   b   2 ,  2304   a   1 ,  2304   b   1 ,  23104   a   1 ,  23104   b   1 ,  2604   b   1 ,  2604   a   2 ) is configured to engage with an engaged portion ( 114   e ,  214   e ) of the release member so as to rotate the release member in the first rotational direction when the toner container is mounted to the image forming apparatus, and 
     wherein the second engagement surface ( 104   a   2 ,  104   b   2 ,  1041   a   2 ,  1042   b   2 ,  1043   a   2 ,  1043   b   2 ,  1044   a   2 ,  1046   a   2 ,  1047   a   2 ,  1048   a   2 ,  204   a   3 ,  204   b   3 ,  2304   a   2 ,  2304   b   2 ,  23104   a   2 ,  23104   b   2 ,  2604   a   3 ,  304   a   3 ,  304   b   3 ,  3104   a   3 ,  3104   b   3 ,  3204   a   3 ,  3204   b   3 ,  604 Ba 2 ,  604 Bb 2 ,  704 Ba 2 ,  704 Bb 2 ,  7204 Ba 2 ,  804   a   3 ) is configured to engage with the engaged portion so as to move upward the release member after the release member is rotated in the first rotational direction by engagement of the release member with the first engagement surface, when the toner container is mounted to the image forming apparatus. 
     Structure Example B2 
     A toner container according to Structure Example B1, wherein when the toner container takes an attitude of being mounted to the image forming apparatus, 
     the accommodating portion, the discharge portion and the engaging portion are arranged in this order in a mounting direction in which the toner container is mounted to the image forming apparatus. 
     Structure Example B3 
     A toner container according to Structure Example B1 or B2, wherein when the toner container takes an attitude of being mounted to the image forming 
     apparatus, at least a part of the second engagement surface is above the first engagement surface. 
     Structure Example B4 
     A toner container according to any one of Structure Examples B1-B3, wherein when the toner container takes an attitude of being mounted to the image forming apparatus, 
     the second engagement surface and the first engagement surface overlap with each other, as views in a mounting direction in which the toner container is mounted to the image forming apparatus. 
     Structure Example B5 
     A toner container according to any one of Structure Examples B1-B4, wherein the engaged portion includes a first engaged surface ( 214   e   2 ) facing upward and a second engaged surface ( 214   e   3 ) facing downward, 
     wherein the first engagement surface and the second engagement surface are configured to engage with the first engaged surface and the second engaged surface, respectively. 
     Structure Example B6 
     A toner container according to any one of Structure Examples B1-B5, wherein when the toner container takes an attitude of being mounted to the image forming apparatus, 
     wherein the second engagement surface faces upward. 
     Structure Example B7 
     A toner container according to Structure Example B6, wherein when the toner container takes an attitude of being mounted to the image forming apparatus, the second engagement surface extends so as to go up as goes in the second rotational direction. 
     Structure Example B8 
     A toner container according to Structure Example B6, wherein when the toner container takes an attitude of being mounted to the image forming apparatus, the second engagement surface is perpendicular to the rotational axis. 
     Structure Example B9 
     A toner container according to Structure Example B6, wherein when the toner container takes an attitude of being mounted to the image forming apparatus, the second engagement surface is an upward surface extending so as to go up as goes in the first rotational direction. 
     Structure Example B10 
     A toner container according to any one of Structure Examples B1-B9, wherein when the toner container takes an attitude of being mounted to the image forming apparatus, the first engagement surface is a surface facing downward. 
     Structure Example B11 
     A toner container according to Structure Example B10, wherein when the toner container takes an attitude of being mounted to the image forming apparatus, the first engagement surface is a downward surface extending so as to go up as goes in the first rotational direction. 
     Structure Example B12 
     A toner container according to any one of Structure Examples B1-B9, wherein the first engagement surface is a surface parallel with the rotational axis. 
     Structure Example B13 
     A toner container according to any one of Structure Examples B1-B12, wherein when the toner container takes an attitude of being mounted to the image forming apparatus, 
     the toner container further comprises a downstream side end surface extending upward along the direction of rotational axis from a downstream end of the second engagement surface and facing downstream side in the second rotational direction. 
     Structure Example B14 
     A toner container according to any one of Structure Examples B1-B13, wherein the first engagement surface and the second engagement surface are exposed to an outside of the toner container. 
     Structure Example B15 
     A toner container according to any one of Structure Examples B1-B14, wherein the image forming apparatus includes a restricting member movable along the rotational axis between a restriction position for restricting rotation of the apparatus side shutter and a release position, above the restriction position, for releasing the rotation restriction of the apparatus side shutter, 
     wherein the release member is configured to move upward with the restricting member so as to move the restricting member from the restriction position to the release position, and 
     wherein the second engagement surface is configured to engage with the engaged portion so as to move upward the release member with the restricting member. 
     Structure Example B16 
     A toner container according to Structure Example B15, wherein the image forming apparatus includes a rise restriction portion for restricting upward movement of the release member, 
     wherein the first engagement surface is configured to engage with the engaged portion so as to rotate the release member in the first rotational direction to a region in which at least upward movement of the release member is not restricted by the rise restriction portion, and 
     wherein the second engagement surface is configured to engage with the engaged portion so that the release member is moved upward with the restricting member in the region. 
     Structure Example B17 
     A toner container according to Structure Example B7, wherein the image forming apparatus includes an urging member for urging the release member in a direction of rotating the release member in the second rotational direction, and 
     wherein the second engagement surface is configured to guide the engaged portion so as to move the release member upward while the release member is being rotated in the second rotational direction by the urging force of the urging member. 
     Structure Example B18 
     A toner container according to Structure Example B13, wherein the image forming apparatus includes an urging member for urging the release member in a direction of rotating the release member in the second rotational direction, 
     wherein the second engagement surface is configured to guide the engaged portion so as to move the release member upward while the release member is being rotated in the second rotational direction by an urging force of the urging member, 
     wherein the release member has a contact surface which is a downstream side end surface in the second rotational direction, and 
     wherein the downstream side end surface of the engaging portion is configured to stop rotation of the release member in the second rotational direction by engaging with the first engagement surface to come into contact with the contact surface of the release member rotated in the second rotational direction. 
     Structure Example B19 
     A toner container according to Structure Example B18, wherein the engaged portion of the release member includes a first engaged surface facing upward and a second engaged surface facing downward below the first engaged surface, and 
     wherein the contact surface is provided between the first engaged surface and the second engaged surface. 
     Structure Example B20 
     A toner container according to Structure Example B18 or B19, comprising a cavity provided right above the second engagement surface, wherein a portion provided with the contact surface of the release member is capable of entering the cavity when the contact surface of the release member contacts the downstream side end surface, when the toner container takes an attitude of being mounted to the image forming apparatus. 
     Structure Example B21 
     A toner container according to any one of Structure Examples B1-B3, wherein when the toner container takes an attitude of being mounted to the image forming apparatus, 
     the engaging portion is configured to be movable upward relative to the discharge portion, and 
     when the engaging portion is moved upward relative to the discharge portion, the second engagement surface pushes the discharge portion from a lower side to move the release member upward. 
     Structure Example B22 
     A toner container according to any one of Structure Examples B10-B12, wherein the first engagement surface pushes the engaged portion of the release member to rotate the release member in the first rotational direction. 
     Structure Example B23 
     A toner container according to any one of Structure Examples B1-B22, wherein the engaged portion of the release member includes a first engaged portion and a second engaged portion which is provided at a position more away from the rotational axis in a radial direction of an imaginary circle centered on the rotational axis than the first engaged portion is, 
     wherein the first engagement surface includes a first inner engagement surface and a first outer engagement surface which is provided at a position more away from the rotational axis in the radial direction than the first inner engagement surface is, 
     wherein the first inner engagement surface is configured to engage with the first engaged portion of the release member so as to rotate the release member in the first rotational direction, and 
     wherein the first outer engagement surface is configured to engage with the second engaged portion so as to further rotate the release member in the first rotational direction after the release member is rotated in the first rotational direction by the engagement with the first inner engagement surface. 
     Structure Example B24 
     A toner container according to Structure Example B23, wherein the image forming apparatus includes a cover covering an upper part of the release member, the cover being provided with a cover opening in a top surface thereof, 
     wherein when the image forming apparatus without the toner container is viewed in a direction of the rotational axis, the cover is configured such that the first engaged portion is exposed through the cover opening, and the second engaged portion is not exposed, 
     wherein when the toner container is mounted to the image forming apparatus, the second engaged portion is exposed through the cover opening as is viewed in the direction of the rotational axis by a rotation of the release member in the first rotational direction by an engagement between the first inner engagement surface and the first engaged portion, and 
     in a state in which the second engaged portion is exposed through the cover opening, the release member is configured to be further rotated in the first rotational direction by engagement of the first outer engagement surface with the second engaged portion. 
     Structure Example B25 
     A toner container according to any one of Structure Examples B1-B5, wherein when the toner container takes an attitude of being mounted to the image forming apparatus, 
     the first engagement surface is a downward surface extending so as to go up as goes in the first rotational direction, 
     the second engagement surface is an upward surface extending so as to go up as goes in the second rotational direction, and 
     the toner container further comprises a connecting portion connecting a downstream end of the first engagement surface in the first rotational direction and an upstream end of the second engagement surface in the second rotational direction, the connecting portion being configured to guide the engaged portion so that a rotational direction of the release member is switched from the first rotational direction to the second rotational direction. 
     Structure Example B26 
     A toner container according to any one of Structure Examples B1-B25, wherein when the toner container takes an attitude of being mounted to the image forming apparatus, 
     the engaging portion is configured to project downward with respect to a lower surface of the toner container. 
     Structure Example C1 
     A toner container for accommodating toner, comprising: 
     an accommodating portion for accommodating toner; 
     a nozzle portion having an outer surface extending in a first direction, the outer surface being provided with a nozzle opening; and 
     a rotatable member configured to be rotatable about a rotational axis extending in a direction along the first direction relative to the nozzle portion, the rotatable member being provided outside of the outer surface of the nozzle portion in the radial direction of an imaginary circle having a center on the rotational axis, 
     wherein when the toner container is oriented such that at least a part of the nozzle portion is below the accommodating portion and the rotational axis extend in a direction of gravity, said toner container comprising a projected portion projecting downward beyond an end surface of the toner container which is below the nozzle opening, the projected portion having an upward surface configured to face upward and to extend so as to go down as goes in a rotational direction of the rotatable member. 
     Structure Example C2 
     A toner container according to Structure Example C1, wherein a cavity is provided above the upward surface of the projected portion. 
     Structure Example C3 
     A toner container according to Structure Example C1 or C2, wherein the projected portion is provided below the upward surface with a downward surface which faces downward and which extends so as to go up as goes in the rotational direction. 
     Structure Example C4 
     A toner container according to Structure Example C3, wherein as viewed in a direction of the rotational axis, the downward surface overlaps the upward surface. 
     Structure Example C5 
     A toner container according to Structure Example C3, wherein the downward surface is provided at a side opposite from the upward surface across the rotational axis in a radial direction. 
     Structure Example C6 
     A toner container according to any one of Structure Examples C1-C5, wherein the projected portion includes a cylindrical portion having a center on rotational axis, and the upward surface is provided at an outer peripheral surface in the radial direction of the cylindrical portion. 
     Structure Example C7 
     A toner container according to Structure Example C6, wherein a bottom surface of the cylindrical portion is provided with a hole having a center on the rotational axis and extending in the direction of the rotational axis. 
     Structure Example C8 
     A toner container according to any one of Structure Examples C1-C7, wherein the upward surface is a first upward surface, 
     the projected portion has a second upward surface on a side opposite from that of the first upward surface across the rotational axis in a direction perpendicular to the rotational axis, and 
     the second upward surface is configured to face upward and to extend so as to go down as goes in the rotational direction of the rotatable member. 
     Structure Example C9 
     A toner container according to any one of Structure Examples C1-C8, wherein the projected portion is configured to take a projecting position in which it is projected downward beyond the end surface and a retracted position in which is retracted so that the bottom surface of the projected portion is above the projecting position. 
     Structure Example C10 
     A toner container according to any one of Structure Examples C1-C8, wherein the upward surface is configured to be movable between an upward position in which it faces upward and extends so as to go down as goes in the rotational direction of the rotatable member, and a position in which a position of the upward surface is different from that in the upward position. 
     Structure Example C11 
     A toner container according to any one of Structure Examples C1-C8, wherein the rotatable member is configured to rotate while rubbing with the outer surface of the nozzle portion between a close position for closing the nozzle opening and an open position for opening the nozzle, and 
     the upward surface extends so as to go down as the rotatable member goes from the close position toward the open position. 
     Structure Example C12 
     A toner container according to Structure Example C11, wherein the outer surface is a first outer surface, 
     the rotatable member is provided with a rotatable member opening for exposing the nozzle opening when it is in the open position, 
     the nozzle portion includes a nozzle recess having a second outer surface recessed beyond the first outer surface in the radial direction at a position different from that of the nozzle opening in the rotational direction, and 
     at least a part of the nozzle recess is exposed through the rotatable member opening when the rotatable member is in the close position. 
     Structure Example C13 
     A toner container according to Structure Example C12, wherein the nozzle recess includes a first nozzle surface and a second nozzle surface arranged in a second direction with the second outer surface interposed therebetween in a cross-section perpendicular to the direction of the rotation axis, the first nozzle and the second nozzle extending in a direction crossing the second direction, and 
     wherein a position of the upward surface of the projected portion is between a position of the first nozzle surface and the position of the second nozzle surface. 
     Structure Example C14 
     A toner container according to Structure Example C12 or C13, wherein the rotatable member provided with a rotatable member recess recessed from an outer surface of the rotatable member at a position opposite from the nozzle recess of the nozzle portion across the rotational axis. 
     Structure Example C15 
     A toner container for accommodating toner, comprising: 
     an accommodating portion for accommodating toner; 
     a nozzle portion having a first outer surface extending in a first direction, the first outer surface being provided with a nozzle opening; 
     a rotatable member configured to be rotatable relative to the nozzle portion about a rotational axis extending along the first direction, the rotatable member being provided outside of the first outer surface of the nozzle portion in a radial direction of an imaginary circle having a center on the rotational axis; and 
     a projection, wherein when the toner container is oriented so that at least a portion of the nozzle portion is below the accommodating portion and the rotational axis extends in a vertical direction, the projected portion is configured to project downward beyond an end surface of the toner container which is below the nozzle opening, and, as viewed in a direction perpendicular to the rotation axis, the projected portion is configured to have an upward surface facing upward and extending so as to go down as goes in a predetermined direction perpendicular to the rotational axis, 
     wherein the rotatable member is provided with a rotatable member opening and configured to be movable between a close position for closing the nozzle opening and an open position for opening the nozzle opening with the nozzle opening exposed through the rotatable member opening, 
     wherein the nozzle portion is provided with a nozzle recess having a second outer surface recessed in the radial direction beyond the first outer surface at a position different from that of the nozzle opening in the rotational direction of the rotatable member, and 
     wherein at least a part of the nozzle recess is exposed through the rotatable member opening when the rotatable member is in the close position. 
     Structure Example C16 
     A toner container according to Structure Example C15, wherein a cavity is provided above the upward surface of the projected portion. 
     Structure Example C17 
     A toner container according to Structure Example C15 or C16, wherein as viewed in a direction perpendicular to the rotational axis, the projected portion has a downward surface configured to face downward and to extend so as to go up as goes in the predetermined direction, below the upward surface. 
     Structure Example C18 
     A toner container according to Structure Example C17, wherein as viewed in a direction of the rotational axis, the downward surface overlaps the upward surface. 
     Structure Example C19 
     A toner container according to Structure Example C18, wherein the downward surface is provided at a side opposite from the upward surface across the rotational axis in a radial direction. 
     Structure Example C20 
     A toner container according to any one of Structure Examples C15-C19, wherein the upward surface is a first upward surface, 
     the projected portion has a second upward surface on a side opposite from that of the first upward surface across the rotational axis in a direction perpendicular to the rotational axis, and 
     the second upward surface is configured to face upward and to extend so as to go down as goes in the predetermined direction, as viewed in a direction perpendicular to the rotational axis. 
     Structure Example C21 
     A toner container according to any one of Structure Examples C15-C20, wherein the nozzle recess includes a first nozzle surface and a second nozzle surface arranged in a second direction with the second outer surface interposed therebetween in a cross-section perpendicular to the direction of the rotation axis, the first nozzle and the second nozzle extending in a direction crossing the second direction, 
     a position of the upward surface of the projected portion is between a position of the first nozzle surface and the position of the second nozzle surface. 
     Structure Example C22 
     A toner container according to any one of Structure Examples C15-C21, wherein the rotatable member is provided with a rotatable member recess recessed from a rotatable member outer surface of the rotatable member on a side opposite from the nozzle recess of the nozzle portion across the rotational axis. 
     Structure Example C23 
     A toner container for accommodating toner, comprising: 
     an accommodating portion for accommodating toner; 
     a nozzle portion having a first outer surface extending in a first direction, the first outer surface being provided with a nozzle opening; 
     a rotatable member configured to be rotatable relative to the nozzle portion about a rotational axis extending along the first direction, the rotatable member being provided outside of the first outer surface of the nozzle portion in a radial direction of an imaginary circle having a center on the rotational axis; and 
     a projection, wherein when the toner container is oriented so that at least a portion of the nozzle portion is below the accommodating portion and the rotational axis extends in a vertical direction, the projected portion is configured to project downward beyond an end surface of the toner container which is below the nozzle opening, and, as viewed in a direction perpendicular to the rotation axis, the projected portion is configured to have an upward surface facing upward and extending so as to go down as goes in a predetermined direction perpendicular to the rotational axis, 
     wherein the nozzle portion is provided with a nozzle recess having a second outer surface recessed in the radial direction beyond the first outer surface at a position different from that of the nozzle opening in the rotational direction of the rotatable member, 
     wherein the nozzle recess includes a first nozzle surface and a second nozzle surface arranged in a second direction with the second outer surface interposed therebetween in a cross-section perpendicular to the direction of the rotation axis, the first nozzle and the second nozzle extending in a direction crossing the second direction, and 
     wherein a position of the upward surface of the projected portion is between a position of the first nozzle surface and the position of the second nozzle surface. 
     Structure Example C24 
     A toner container according to Structure Example C23, wherein a cavity is provided above the upward surface of the projected portion. 
     Structure Example C25 
     A toner container according to Structure Example C23 or C24, wherein as viewed in a direction perpendicular to the rotational axis, the projected portion has a downward surface configured to face downward and to extend so as to go up as goes in the predetermined direction, below the upward surface. 
     Structure Example C26 
     A toner container according to Structure Example C25, wherein as viewed in a direction of the rotational axis, the downward surface overlaps the upward surface. 
     Structure Example C27 
     A toner container according to Structure Example C25, wherein the downward surface is provided at a side opposite from the upward surface across the rotational axis in a radial direction. 
     Structure Example C28 
     A toner container according to any one of Structure Examples C23-C26, wherein the upward surface is a first upward surface, 
     wherein the projected portion has a second upward surface on a side opposite from that of the first upward surface across the rotational axis in a direction perpendicular to the rotational axis, and 
     the second upward surface is configured to face upward and to extend so as to go down as goes in the predetermined direction, as viewed in a direction perpendicular to the rotational axis. 
     Structure Example C29 
     A toner container for accommodating toner, comprising: 
     an accommodating portion for accommodating toner; and 
     a nozzle portion having an outer surface extending in a first direction, the outer surface being provided with a nozzle opening; 
     wherein when the toner container is oriented such that at least a part of the nozzle portion is below the accommodating portion and the rotational axis extend in a direction of gravity, said toner container comprising a projected portion projecting downward beyond an end surface of the toner container which is below the nozzle opening, the projected portion having an upward surface configured to face upward and to extend so as to go down as goes in a predetermined direction perpendicular to the first direction, as is viewed in the direction perpendicular to the first direction, and 
     wherein a ridge of the upward surface extends so as to go down as goes in the predetermined direction. 
     Structure Example C30 
     A toner container according to Structure Example C29, wherein the projected portion is configured to have a downward surface faces downward and which extends so as to go up as goes in the predetermined direction below the upward surface, and 
     the downward surface extends such that the ridge of the downward surface goes up as goes in the predetermined direction. 
     Structure Example C31 
     An image forming system comprising a toner container and an image forming apparatus ( 1 ) to which the toner container is mountable, 
     wherein the toner container includes, 
     a first accommodating portion for accommodating toner, 
     a nozzle portion having an outer surface extending downward, 
     a rotatable member rotatable relative to the nozzle portion about a rotational axis extending downward and provided outside the outer surface of the nozzle portion in a radial direction of an imaginary circle having a center on the rotational axis, the rotatable member including a push portion, and 
     a projected portion configured to project downward beyond an end surface of the toner container below the nozzle opening, the projected portion having an upward surface facing upward and extending so as to go down as goes in a direction of the rotatable member, 
     wherein the image forming apparatus includes, 
     a photosensitive drum, 
     a developing roller for supplying the toner to the photosensitive drum, 
     a second accommodating portion for accommodating the toner supplied from the toner container, 
     a mounting portion to which the toner container is mountable, 
     a frame provided with a frame opening in fluid communication with the second accommodating portion, 
     a shutter including a rotation restricted portion and a pushed portion and provided with a shutter opening, the shutter being rotatable about the rotational axis between a close position in which the shutter opening not in fluid communication with the frame opening and an open position in which the shutter is in fluid communication with the frame opening, and the pushed portion being configured to engage with the push portion of the rotatable member of the toner container, 
     a restricting member including a rotation restriction portion a movable in a direction of the rotational axis between a restriction position for restricting rotation of the shutter from the close position to the open position by engagement of the rotation restriction portion with the rotation restricted portion of the shutter and a release position for releasing rotation restriction from the movable to the open position of the shutter, the release position being above the restriction position, 
     a release member including an engaging portion extending upward and rotatable in a first rotational direction about the rotational axis and movable upward with the restricting member so that the restricting member moves from the restriction position to the release position, and 
     an urging member for urging the release member in a direction to rotate the release member in the first rotational direction, 
     wherein when the toner container is moved down toward the mounting portion, 
     after the engaging portion is rotated by contact with the projected portion of the toner container against an urging force of the urging member in a second rotational direction opposite to the first rotational direction, the release member is ridden on the upward surface by the urging force of the urging member and is moved up along the upward surface while being rotated in the first rotational direction, thus being moved from the restriction position to the release position, and 
     when the mounting of the toner container to the mounting portion is completed, the restricting member is in the release position, and by rotation of the rotatable member, the pushed portion of the shutter is pushed by the push portion of the rotatable member to rotate the shutter from the close position to the open position. 
     Structure Example C32 
     An image forming system according to Structure Example C31, wherein a cavity is provided above the upward surface of the projected portion. 
     Structure Example C33 
     An image forming system according to Structure Example C31 or C32, wherein the projected portion is provided below the upward surface with a downward surface which faces downward and which extends so as to go up as goes in the rotational direction. 
     Structure Example C34 
     An image forming system according to Structure Example C33, wherein as viewed in a direction of the rotational axis, the downward surface overlaps the upward surface. 
     Structure Example C35 
     An image forming system according to Structure Example C33, wherein the downward surface is provided at a side opposite from the upward surface across the rotational axis in a radial direction. 
     Structure Example C36 
     An image forming system according to any one of Structure Examples C31-C35, wherein the projected portion includes a cylindrical portion having a center on the rotational axis, and 
     the upward surface is provided on an outer peripheral surface in the radial direction of the cylindrical portion. 
     Structure Example C37 
     An image forming system according to Structure Example C36, wherein a bottom surface of the cylindrical portion is provided with a hole having a center on the rotational axis and extending in the direction of the rotational axis. 
     Structure Example C38 
     An image forming system according to any one of Structure Examples C31-C37, wherein the upward surface is a first upward surface, 
     wherein the projected portion has a second upward surface on a side opposite from that of the first upward surface across the rotational axis in a direction perpendicular to the rotational axis, and 
     wherein the second upward surface is configured to face upward and to extend so as to go down as goes in the rotational direction of the rotatable member. 
     Structure Example C39 
     An image forming system according to any one of Structure Examples C31-C38, wherein the projected portion is configured to take a projecting position in which it is projected downward beyond the end surface and a retracted position in which is retracted so that the bottom surface of the projected portion is above the projecting position. 
     Structure Example C40 
     An image forming system according to any one of Structure Examples C31-C38, wherein the upward surface is movable between a first position in which it extends so as to go down as goes in a rotational direction of the rotatable member and faces upward, and a second position in which upward surface faces in a direction different from that in the first position. 
     Structure Example C41 
     An image forming system according to any one of Structure Examples C31-C38, wherein the rotatable member is configured to rotate while rubbing with the outer surface of the nozzle portion between a close position for closing the nozzle opening and an open position for opening the nozzle, and 
     wherein the upward surface extends so as to go down as the rotatable member goes from the close position toward the open position. 
     Structure Example C42 
     An image forming system according to Structure Example C41, wherein the outer surface is a first outer surface, 
     wherein the rotatable member is provided with a rotatable member opening for exposing the nozzle opening when it is in the open position, 
     wherein the nozzle portion includes a nozzle recess having a second outer surface recessed beyond the first outer surface in the radial direction at a position different from that of the nozzle opening in the rotational direction, and 
     wherein at least a part of the nozzle recess is exposed through the rotatable member opening when the rotatable member is in the close position. 
     Structure Example C43 
     An image forming system according to Structure Example C42, wherein the nozzle recess includes a first nozzle surface and a second nozzle surface arranged in a second direction with the second outer surface interposed therebetween in a cross-section perpendicular to the direction of the rotation axis, the first nozzle and the second nozzle extending in a direction crossing the second direction, and 
     wherein a position of the upward surface of the projected portion is between a position of the first nozzle surface and the position of the second nozzle surface. 
     Structure Example C44 
     An image forming system according to Structure Example C42 or C43, wherein the rotatable member provided with a rotatable member recess recessed from an outer surface of the rotatable member at a position opposite from the nozzle recess of the nozzle portion across the rotational axis. 
     Structure Example C45 
     An image forming system according to any one of Structure Examples C31-C44, wherein the urging member is there first urging member, and the image forming apparatus includes a second urging member for urging the restricting member in a direction of moving the restricting member from the release position to the restriction position. 
     Structure Example C46 
     A mounting kit for mounting to an image forming apparatus, the mounting kit comprising a toner container for accommodating toner, an attachment, 
     wherein the toner container including, 
     an accommodating portion for accommodating toner; 
     a nozzle portion having an outer surface extending in a first direction, the outer surface being provided with a nozzle opening; 
     a rotatable member configured to be rotatable about a rotational axis extending in a direction along the first direction relative to the nozzle portion, the rotatable member being provided outside of the outer surface of the nozzle portion in the radial direction of an imaginary circle having a center on the rotational axis, and 
     wherein the attachment has a cylindrical shape with an outer peripheral surface having a center thereof on a central axis, and wherein when the attachment is oriented such that the central axis extends in a vertical direction, the attachment has an upward surface configured to extend so as to go down as goes in a circumferential direction of the outer peripheral surface and to face upward. 
     Structure Example C47 
     A mounting kit according to Structure Example C46, wherein the attachment has a downward surface configured to extend so as to go up as goes in the circumferential direction of the outer peripheral surface and to face downward. 
     Structure Example C48 
     A mounting kit according to Structure Example C46 or C47, wherein the attachment is configured to be mountable to the nozzle portion of the toner container. 
     Structure Example C49 
     An image forming system comprising an image forming apparatus and an attachment mountable to the image forming apparatus, 
     wherein the image forming apparatus includes, 
     a photosensitive drum, 
     a developing roller ( 31 ) for supplying the toner to the photosensitive drum, 
     an accommodating portion for accommodating toner to be supplied to the developing roller, 
     a mounting portion to which the attachment is mountable, the mounting portion including, 
     a frame provided with a frame opening in fluid communication with the accommodating portion, 
     a shutter including a rotation restricted portion and provided with a shutter opening, the shutter being movable between a close position in which the shutter opening is not fluid communication with the frame opening, and an open position in which the shutter opening is in fluid communication with the frame opening, 
     a restricting member including a rotation restriction portion a movable in a direction of the rotational axis between a restriction position for restricting rotation of the shutter from the close position to the open position by engagement of the rotation restriction portion with the rotation restricted portion of the shutter and a release position for releasing rotation restriction from the movable to the open position of the shutter, the release position being above the restriction position, and 
     a release member including an engaging portion extending upward and rotatable in a first rotational direction about the rotational axis and movable upward with the restricting member so that the restricting member moves from the restriction position to the release position, and 
     an urging member for urging the release member in a direction to rotate the release member in the first rotational direction, and 
     wherein the attachment has a cylindrical shape with an outer peripheral surface having a center thereof on the central axis, wherein when the attachment is oriented such that central axis extends a vertical direction, the attachment has an upward surface configured to extend so as to go down as goes in a circumferential direction of the outer peripheral surface and to face upward, and 
     wherein when the attachment moved down toward the mounting portion, 
     after the engaging portion is rotated by contact with the attachment against an urging force of the urging member in a second rotational direction opposite to the first rotational direction, the release member is ridden on the upward surface of the attachment by the urging force of the urging member and is moved up along the upward surface while being rotated in the first rotational direction, thus being moved from the restriction position to the release position, and wherein when mounting of the attachment to the mounting portion, the restricting member is in the release position. 
     Structure Example C50 
     An image forming system according to Structure Example C49, further comprising a toner container including, an accommodating portion for accommodating toner, 
     a nozzle portion having an outer surface extending in a first direction, the outer surface being provided with a nozzle opening, and 
     a rotatable member including a push portion and configured to be rotatable relative to the nozzle portion about a rotational axis extending in the first direction, the rotatable member being provided outside an outer surface of the nozzle portion in a radial direction of an imaginary circle having a center on rotational axis, 
     wherein the toner container being mountable to the mounting portion after the attachment is mounted to the mounting portion, 
     wherein the shutter of the mounting portion includes a pushed portion engaged with the push portion when the toner container is mounted to the mounting portion, and 
     wherein when the rotatable member of the toner container is rotated, the shutter is moved from the close position to the open position by the pushed portion of the shutter being pushed by the push portion of the rotatable member. 
     Structure Example C51 
     A rotation restriction releasing method for a shutter of an image forming apparatus to which a toner container is mountable, 
     wherein the image forming apparatus including, 
     a photosensitive drum, 
     a developing roller for supplying the toner to the photosensitive drum, 
     an accommodating portion for accommodating toner supplied from the toner container, and 
     a mounting portion to which the toner container is mountable, the mounting portion including, 
     a frame provided with a rise restriction portion and a frame opening in fluid communication with the accommodating portion, 
     a shutter including a rotation restricted portion and provided with a shutter opening, the shutter being rotatable about a rotational axis between a close position in which the shutter opening is not in fluid communication with the frame opening, and an open position in which the shutter opening is in fully communication with the frame opening, 
     a restricting member including a rotation restriction portion a movable in a direction of the rotational axis between a restriction position for restricting rotation of the shutter from the close position to the open position by engagement of the rotation restriction portion with the rotation restricted portion of the shutter and a release position for releasing rotation restriction from the movable to the open position of the shutter, the release position being above the restriction position, 
     a release member including an engaging portion extending upward, and a rise restricted portion, the release member being rotatable about the rotational axis between a rise restriction position in which the rise restricted portion is locked by the rise restriction portion and the rise restricted portion is restricted in movement together with the restricting member so that the restricting member moves from the restriction position to the release position, and a rise restriction release position in which the rise restricted portion is not locked by the rise restriction portion and the rise restricted portion is movable together with the restricting member so that the restricting member moves from the restriction position to the release position, and 
     an urging member for urging the release member in a direction of rotating the release member from the rise restriction release position to the rise restriction position, 
     the method comprising: 
     a first step of rotating the release member against an urging force of the urging member from the rise restriction position to the rise restriction release position; and 
     a second step of moving the release member together with the restricting member so that the restricting member moves from the restriction position to the release position, after the first step. 
     Structure Example D1 
     An image forming system comprising an image forming apparatus and a toner container mountable to the image forming apparatus, 
     wherein the image forming apparatus including, 
     an apparatus side shutter ( 109 ,  209 ) rotatable to be brought into fluid communication with a toner receiving opening ( 117   a ,  217   a ), and 
     a release member ( 114 ,  214 ) for releasing rotation restriction for the apparatus side shutter, the release member rotatable about a rotational axis in a first rotational direction and a second rotational direction opposite to the first rotational direction and movable upward, and 
     wherein the toner container including, 
     an accommodating portion configured to accommodate toner ( 101 ,  1015 ,  10151 ,  201 ,  2401 ,  2801 ,  501 ,  901 ), 
     a discharge portion ( 102 ,  1025 ,  202 ,  2302 ,  23102 ,  2402 A,  2502 ,  2503 ,  2802 ,  302 ,  502 ,  5102 ,  902 ,  1002 A,  1102 ) configured to provide an opening ( 102   a ,  202   a ,  2402 Ag,  2502   k   2 ,  2503   k   2 ,  2802   a ,  302   a ,  502   a ,  902 Dk,  10020 De) for discharging the toner in the accommodating portion to the receiving opening; and 
     an engaging portion ( 202 D,  2302 D,  23102 D,  2402 DD,  2502 D,  2503 D,  2802 D,  304 ,  3104 ,  3204 ,  502 D,  5102 D,  604 ,  804 ,  8104 ,  8204 ,  8304 ,  903 Dg,  1003 D,  1132 D) having a first engagement surface and a second engagement surface, 
     wherein when the toner container is mounted to the image forming apparatus, 
     the first engagement surface ( 104   a   1 ,  104 D 1 ,  1041 D 1 ,  1042   a   1 ,  1043   a   1 ,  1043 D 1 ,  1044   a   1 ,  1046   a   1 ,  1047   a   1 ,  1048   a   1 ,  204   a   1 ,  204   a   2 ,  204 D 1 ,  204 D 2 ,  2304   a   1 ,  2304 D 1 ,  23104   a   1 ,  23104 D 1 ,  2604 D 1 ,  2604   a   2 ) is engaged with an engaged portion ( 114   e ,  214   e ) of the release member so that the release member is rotated in the first rotational direction, and 
     the second engagement surface ( 104   a   2 ,  104 D 2 ,  1041   a   2 ,  1042 D 2 ,  1043   a   2 ,  1043 D 2 ,  1044   a   2 ,  1046   a   2 ,  1047   a   2 ,  1048   a   2 ,  204   a   3 ,  204 D 3 ,  2304   a   2 ,  2304 D 2 ,  23104   a   2 ,  23104 D 2 ,  2604   a   3 ,  304   a   3 ,  304 D 3 ,  3104   a   3 ,  3104 D 3 ,  3204   a   3 ,  3204 D 3 ,  604 Da 2 ,  604 DD 2 ,  704 Da 2 ,  704 DD 2 ,  7204 Da 2 ,  804   a   3 ) is engaged with the engaged portion so that after the release member is rotated in the first rotational direction by engagement with the first engagement surface, the release member is moved upward. 
     Structure Example D2 
     An image forming system according to Structure Example D1, wherein when the toner container is mounted on the image forming apparatus, 
     the accommodating portion, the discharge portion and the engaging portion of the toner container are arranged in this order in a mounting direction in which the container is mounted to the image forming apparatus. 
     Structure Example D3 
     An image forming system according to Structure Example D1 or D2, wherein when the toner container is mounted on the image forming apparatus, 
     at least a part of the second engagement surface is above the first engagement surface. 
     Structure Example D4 
     An image forming system according to any one of Structure Examples D1-D3, wherein when the toner container is mounted on the image forming apparatus, and 
     the second engagement surface and the first engagement surface overlap with each other, as views in a mounting direction in which the toner container is mounted to the image forming apparatus. 
     Structure Example D5 
     An image forming system according to any one of Structure Examples D1-D4, wherein the engaged portion of the release member has a first engaged surface ( 214   e   2 ) facing upward and a second engaged surface ( 214   e   3 ) facing downward, and 
     wherein the first engagement surface and the second engagement surface are configured to engage with the first engaged surface and the second engaged surface, when the toner container is mounted to the image forming apparatus. 
     Structure Example D6 
     An image forming system according to any one of Structure Examples D1-D5, wherein when the toner container is mounted on the image forming apparatus, the second engagement surface faces upward. 
     Structure Example D7 
     An image forming system according to Structure Example D6, wherein when the toner container is mounted on the image forming apparatus, the second engagement surface extends so as to go up as goes in the second rotational direction. 
     Structure Example D8 
     An image forming system according to Structure Example D6, wherein when the toner container is mounted on the image forming apparatus, 
     the second engagement surface is perpendicular to the rotational axis. 
     Structure Example D9 
     An image forming system according to Structure Example D6, wherein when the toner container is mounted on the image forming apparatus, 
     the second engagement surface extends so as to go up as goes in the first rotational direction. 
     Structure Example D10 
     An image forming system according to any one of Structure Examples D1-D9, wherein when the toner container is mounted on the image forming apparatus, the first engagement surface faces downward. 
     Structure Example D11 
     An image forming system according to Structure Example D10, wherein when the toner container is mounted on the image forming apparatus, the first engagement surface is a downward surface extending so as to go up as goes in the first rotational direction. 
     Structure Example D12 
     An image forming system according to any one of Structure Examples D1-D9, wherein the first engagement surface is a surface parallel with the rotational axis. 
     Structure Example D13 
     An image forming system according to any one of Structure Examples D1-D12, wherein when the toner container is mounted on the image forming apparatus, the toner container further comprises a downstream side end surface extending upward along the direction of rotational axis from a downstream end of the second engagement surface and facing downstream side in the second rotational direction. 
     Structure Example D14 
     An image forming system according to any one of Structure Examples D1-D13, wherein the first engagement surface and the second engagement surface of the toner container are exposed to an outside of the toner container so as to be engageable with the engaged portion of the release member. 
     Structure Example D15 
     An image forming system according to any one of Structure Examples D1-D14, wherein the image forming apparatus includes a restricting member movable along the rotational axis between a restriction position for restricting rotation of the apparatus side shutter and a release position, above the restriction position, for releasing the rotation restriction on the apparatus side shutter, and 
     wherein the release member is configured to move upward with the restricting member so as to move the restricting member from the restriction position to the release position, and 
     wherein the second engagement surface is engaged with the engaged portion so that the release member moves upward together with the restricting member, when the toner container is mounted to the image forming apparatus. 
     Structure Example D16 
     An image forming system according to Structure Example D15, wherein the image forming apparatus includes a rise restriction portion for restricting upward movement of the release member, 
     wherein when the toner container is mounted to the image forming apparatus, 
     the first engagement surface is engaged with the engaged portion so that the release member is rotated in the first rotational direction two and the region in which at least upward movement of the release member is not restricted by the rise restriction portion, 
     the second engagement surface is engaged with the engaged portion so that the release member is moved upward together with the restricting member. 
     Structure Example D17 
     An image forming system according to Structure Example D7, wherein the image forming apparatus includes an urging member for urging the release member in a direction of rotating the release member in the second rotational direction, and 
     wherein when the toner container is mounted to the image forming apparatus, the second engagement surface guides the engaged portion so that the release member is moved upward by an urging force of the urging member, while being rotated in the second rotational direction. 
     Structure Example D18 
     An image forming system according to Structure Example D13, wherein the image forming apparatus includes an urging member for urging the release member in a direction of rotating the release member in the second rotational direction, and the second engagement surface guides the engaged portion when the toner container is mounted to the image forming apparatus, so that the release member is moved upward while being rotated in the second the rotational direction by the urging force of the urging member, 
     wherein the release member has a contact surface which is a downstream side end surface in the second rotational direction, and 
     wherein the downstream side end surface of the engaging portion is configured to stop rotation of the release member in the second rotational direction by engaging with the first engagement surface to come into contact with the contact surface of the release member rotated in the second rotational direction. 
     Structure Example D19 
     An image forming system according to Structure Example D18, wherein the engaged portion of the release member as a first engaged surface facing upward, and a second engaged surface facing downward below the first engaged surface, and the contact surface provided between the first engaged surface and the second engaged surface. 
     Structure Example D20 
     An image forming system according to Structure Example D18 or D19, wherein when the toner container is mounted on the image forming apparatus, a cavity is provided right above the second engagement surface, wherein when the contact surface of the release member is brought into contact with the downstream side and the surface, a portion of the release member which is provided with a contact surface enters the cavity. 
     Structure Example D21 
     An image forming system according to any one of Structure Examples D1-D3, wherein when the toner container is mounted on the image forming apparatus, 
     the engaging portion is configured to be movable upward relative to the discharge portion, and 
     when the engaging portion is moved upward relative to the discharge portion, the second engagement surface pushes the discharge portion from a lower side to move the release member upward. 
     Structure Example D22 
     An image forming system according to any one of Structure Examples D10-D12, wherein the first engagement surface pushes the engaged portion of the releasing member to rotate the releasing member in the first rotational direction. 
     Structure Example D23 
     An image forming system according to any one of Structure Examples D1-D22, wherein the engaged portion of the release member includes a first engaged portion and a second engaged portion which is provided at a position more away from the rotational axis in a radial direction of an imaginary circle having a center on the rotational axis than the first engaged portion, 
     wherein the first engagement surface includes a first inner engagement surface and a first outer engagement surface which is provided at a position more away from the rotational axis in the radial direction than the first inner engagement surface, 
     wherein when the toner container is mounted to the image forming apparatus, 
     the first inner engagement surface is engaged with the first engaged portion of the release member so that the release member is rotated in the first rotational direction, and 
     the first outer engagement surface is engaged with the second engaged portion so that after the release member is rotated in the first rotational direction through engagement with the engagement surface, the release member is further rotated in the first rotational direction. 
     Structure Example D24 
     An image forming system according to Structure Example D23, wherein the image forming apparatus includes a cover covering a part of the release member at an upper part, the cover being provided with a cover opening in a top surface thereof, 
     when the image forming apparatus without the toner container is viewed in a direction of the rotational axis, the cover is configured such that the first engaged portion is exposed through the cover opening, and the second engaged portion is not exposed, 
     when the toner container is mounted to the image forming apparatus, the first inner engagement surface is engaged with the first engaged portion to rotate the release member in the first rotational direction, the second engaged portion is exposed through the cover opening as is viewed in the direction of the rotational axis, and 
     in a state in which the second engaged portion exposed through the cover opening, the release member is configured to be further rotated in the first rotational direction by engagement of the first outer engagement surface with the second engaged portion. 
     Structure Example D25 
     An image forming system according to any one of Structure Examples D1-D5, wherein when the toner container is mounted on the image forming apparatus, 
     the first engagement surface is a downward surface extending so as to go up as goes in the first rotational direction, 
     the second engagement surface is an upward surface extending so as to go up as goes in the second rotational direction, 
     the toner container further comprises a connecting portion connecting a downstream end of the first engagement surface in the first rotational direction and an upstream end of the second engagement surface in the second rotational direction, the connecting portion being configured to guide the engaged portion so that a rotational direction of the release member is switched from the first rotational direction to the second rotational direction. 
     Structure Example D26 
     An image forming system according to any one of Structure Examples D1-D25, wherein when the toner container is mounted on the image forming apparatus, the engaging portion is configured to project downward with respect to a lower surface of the toner container. 
     INDUSTRIAL APPLICABILITY 
     According to the present invention, there is provided a toner container mountable to an image forming apparatus, and an image forming system. 
     The present invention is not limited to the above embodiments, and various modifications and modifications can be made without departing from the spirit and scope of the present invention. 
     Therefore, the following Structure Examples are attached to publicize the scope of the present invention. 
     This application Structure Examples priority on the basis of Japanese Patent Application Patent Application No. 2020-202977 filed on Dec. 7, 2020, and all of the contents thereof are incorporated herein.