Abstract:
A developer cartridge that can be attached to and detached from an image forming apparatus and contains developer, the developer cartridge comprising: a first body that has an opening for supplying the developer; a second body that covers the first body, the second body having a conductive portion that can transmit electricity; and a memory unit that is disposed between the first body and the second body, the memory unit can be connected to a terminal of the image forming apparatus through the conductive portion of the second body, wherein the second body and the first body are movable relative to each other, the second body is able to open and close the opening by a relative movement with regard to the first body.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    The present application claims priority from Japanese Patent Application No. 2007-062029, which was filed on Mar. 12, 2007, the disclosure of which is herein incorporated by reference in its entirety. 
       TECHNICAL FIELD 
       [0002]    The present invention relates to a developer cartridge having a memory chip. 
       BACKGROUND 
       [0003]    In general, an image forming apparatus such as a laser printer includes a main body, a process cartridge having a developing roller, and a developer cartridge containing a toner. In the image forming apparatus, the developer cartridge can be attached to and detached from the process cartridge and the process cartridge can be attached to and detached from the main body of the apparatus. 
         [0004]    A memory chip that stores a variety of information relating to the developer cartridge is disposed in the developer cartridge. When the developer cartridge is attached to the image forming apparatus through the process cartridge, the memory chip is electrically connected to a terminal disposed in the image forming apparatus body directly or through a conductive portion disposed in the process cartridge. In this way, the image forming apparatus acquires the variety of information stored in the memory chip. 
         [0005]    As such a technology, a structure is known in which a panel-like cover covering a contact terminal of a memory chip is rotatably disposed in a developer cartridge (see Patent Document 1). When the developer cartridge is attached to a process cartridge, an end of the cover comes in contact with a part of the process cartridge and the other end of the cover pivots, whereby the contact terminal of the memory chip is exposed and is thus connected to a contact terminal of the process cartridge. According to this structure, since the contact terminal of the memory chip is covered with the cover in a state where the developer cartridge is not attached to the process cartridge, it is possible to prevent contamination or damage of the memory chip.
   [Patent Document 1] Japanese Unexamined Patent Application Publication No. 2006-221010   
 
       SUMMARY 
       [0007]    However, the above-described apparatus disclosed in Patent Document 1 has a following problem. Since a cover should be independent of existing parts (for example, a shutter for opening and closing a toner supply port) in the developer cartridge, there is a problem that the cartridge is complicated. 
         [0008]    An object of the invention is to provide a developer cartridge which can suppress contamination or damage of a memory chip (memory unit) and which can simplify a configuration thereof. 
         [0009]    In order to accomplish the above-mentioned object, according to an aspect of the invention, there is provided a developer cartridge that can be attached to and detached from an image forming apparatus and contains developer, the developer cartridge comprising: a first body that has an opening for supplying the developer; a second body that covers the first body, the second body having a conductive portion that can transmit electricity; and a memory unit that is disposed between the first body and the second body, the memory unit can be connected to a terminal of the image forming apparatus through the conductive portion of the second body, wherein the second body and the first body are movable relative to each other, the second body is able to open and close the opening by a relative movement with regard to the first body. 
         [0010]    According to this configuration, since the memory unit is disposed between the first body and the second body and is connected to the terminal of the image forming apparatus through the conductive portion of the second body, the memory unit is always protected by the second body, thereby preventing contamination or damage thereof. That is, since the memory unit is hidden in the second body by only disposing the conductive portion in the outer body, the conventional particular mechanism is not necessary, thereby further simplifying the device configuration. 
         [0011]    According to the invention, since the memory unit can be protected by the second body by only disposing the conductive portion in the second body, it is possible to prevent the contamination or damage of the memory unit and to further simplify the device configuration. Since the memory unit is protected by the second body serving as a shutter of the opening, it is possible to further simplify the device configuration. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    Illustrative aspects of the invention will be described in detail with reference to the following figures wherein: 
           [0013]      FIG. 1  is a side sectional view illustrating a laser printer according to an embodiment of the invention; 
           [0014]      FIG. 2  is a sectional view illustrating a process cartridge according to an embodiment of the invention; 
           [0015]      FIG. 3  is a plan view illustrating a toner cartridge; 
           [0016]      FIG. 4A  is a sectional view illustrating a relation between a memory chip and a conductive portion when an inner opening and an outer opening are closed,  FIG. 4B  is a sectional view illustrating a relation between the memory chip and the conductive portion when the inner opening and the outer opening communicate with each other, and  FIG. 4C  is a sectional view illustrating a relation among the memory chip, the conductive portion, and a terminal when the toner cartridge is attached to a main casing; 
           [0017]      FIG. 5  is a plan view illustrating a toner cartridge according to another embodiment of the invention; 
           [0018]      FIG. 6A  is a sectional view illustrating a relation between the memory chip and the conductive portion when the inner opening and the outer opening are closed in the example shown in  FIG. 5 ,  FIG. 6B  is a sectional view illustrating a relation between the memory chip and the conductive portion when the inner opening and the outer opening communicate with each other, and  FIG. 6C  is a sectional view illustrating a relation among the memory chip, the conductive portion, and a terminal when the toner cartridge is attached to a main casing; 
           [0019]      FIG. 7A  to  FIG. 7C  are diagrams illustrating an example where the conductive portion is always connected to the contact terminal of the memory chip,  FIG. 7A  is a sectional view illustrating a relation between the memory chip and the conductive portion when the inner opening and the outer opening are closed,  FIG. 7B  is a sectional view illustrating a relation between the memory chip and the conductive portion when the inner opening and the outer opening communicate with each other, and  FIG. 7C  is a sectional view illustrating a relation among the memory chip, the conductive portion, and a terminal when the toner cartridge is attached to a main casing; and 
           [0020]      FIG. 8A  to  FIG. 8C  are diagrams illustrating a modified example of the example shown in  FIG. 7 ,  FIG. 8A  is a sectional view illustrating a relation between the memory chip and the conductive portion when the inner opening and the outer opening are closed,  FIG. 8B  is a sectional view illustrating a relation between the memory chip and the conductive portion when the inner opening and the outer opening communicate with each other, and  FIG. 8C  is a sectional view illustrating a relation among the memory chip, the conductive portion, and a terminal when the toner cartridge is attached to a main casing. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0021]    Hereinafter, an exemplary embodiment of the invention will be described in detail with reference to the attached drawings.  FIG. 1  is a side sectional view illustrating a laser printer according to an exemplary embodiment of the invention. In the following description, the entire configuration of a laser printer is first explained in brief and then detailed features of the invention will be explained. In the following description, directions are based on a user using a laser printer  1 . That is, in  FIG. 1 , the right side is defined as a “near side”, the left side is defined as a “far side”, the far side in the direction perpendicular to the sheet surface is defined as a “right side”, and the near side in the direction perpendicular to the surface of the fig sheet is defined as a“left side.” Since the vertical direction shown in the figures is equal to the vertical direction at the time when the user uses the apparatus, the vertical direction is defined as a “vertical direction.” 
       &lt;Entire Configuration of Laser Printer&gt; 
       [0022]    As shown in  FIG. 1 , a laser printer  1  as an example of the image forming apparatus includes a feeder unit  4  that feeds a sheet  3  into a main casing  2  as an example of a main body of the apparatus and an image forming unit  5  that forms an image on the fed sheet  3 . 
       &lt;Configuration of Feeder Unit&gt; 
       [0023]    The feeder unit  4  includes a sheet feeding tray  6  that is detachably attached to the bottom of the main casing  2  and a sheet pressing plate  7  that is disposed in the sheet feeding tray  6 . The feeder unit  4  further includes various rollers  11  that conveys the sheet  3  or removes sheet powders. 
         [0024]    In the feeder unit  4  having the above-mentioned configuration, the sheet  3  in the sheet feeding tray  6  is sent to the upper side of the sheet pressing plate  7  and is conveyed to the image forming unit  5  by the various rollers  11 . 
       &lt;Configuration of Image Forming Unit&gt; 
       [0025]    The image forming unit  5  includes a scanner unit  16 , a process cartridge  17 , and a fixing unit  18 . 
       &lt;Configuration of Scanner Unit&gt; 
       [0026]    The scanner unit  16  is disposed in the upper portion of the main casing  2  and includes a laser-emitting portion (not shown), a polygon mirror  19  that is rotationally driven, lenses  20  and  21 , and reflecting mirrors  22 ,  23 , and  24 . A laser beam based on image data and emitted from the laser-emitting portion is transmitted or reflected by the polygon mirror  19 , the lens  20 , the reflecting mirror  22 , the reflecting mirror  23 , the lens  21 , and the reflecting mirror  24  in this order as indicated by a dotted line and then is applied to the surface of a photosensitive drum  27  of the process cartridge  17  at a high speed. 
       &lt;Configuration of Process Cartridge&gt; 
       [0027]    The process cartridge  17  is detachably attached to the main casing  2  when a front cover  2   a , which is disposed in the front of the main casing  2 , opens. The process cartridge  17  includes a developing cartridge  28  and a drum unit  51 . 
         [0028]    The developing cartridge  28  can be attached to and detached from the main casing  2  in a state where it is fitted to the drum unit  51 . The developing cartridge  28  maybe freely attached to and detached from the drum unit  51  fixed to the main casing  2 . 
         [0029]    The developing cartridge  28  includes a toner cartridge  100  that can be attached to and detached from the developing cartridge, a developing roller  31 , a thickness regulating blade  32 , and a supply roller  33 . A toner in the toner cartridge  100  is agitated by an agitator  100   a  and is then supplied to the developing roller  31  by the supply roller  33 . At this time, the toner is frictionally charged positive between the supply roller  33  and the developing roller  31 . The toner supplied to the developing roller  31  enters between the thickness regulating blade  32  and the developing roller  31  and is held as a thin layer having a constant thickness on the developing roller  31 , with the rotation of the developing roller  31 . 
         [0030]    The drum unit  51  includes a photosensitive drum  27 , a scorotron charging unit  29 , and a transfer roller  30 . 
         [0031]    The photosensitive drum  27  is rotatably supported in the body of the drum unit  51 . 
         [0032]    The scorotron charging unit  29  is a positive scorotron charging unit for generating a corona discharge from a charging wire made of tungsten or the like and serves to charge the surface of the photosensitive drum  27  to be uniformly positive. 
         [0033]    The transfer roller  30  is disposed below the photosensitive drum  27  so as to come in opposed contact with the photosensitive drum  27 . And the transfer roller  30  is rotatably supported in the body of the drum unit  51 . A transfer bias is applied to the transfer roller  30  based on the static current control at the time of transfer. 
         [0034]    The surface of the photosensitive drum  27  is uniformly charged positive by the scorotron charging unit  29  and then is exposed to a laser beam from the scanner unit  16  at a high speed. Accordingly, the potential of the exposed portion is lowered to form an electrostatic latent image based on image data. Here, the “electrostatic latent image” means an exposed portion which is exposed to the laser beam and is lowered in potential on the surface of the photosensitive drum  27  uniformly charged positive. And, with the rotation of the developing roller  31 , the toner held on the developing roller  31  is supplied to the electrostatic latent image formed on the surface of the photosensitive drum  27  at the time of coming in contact with the photosensitive drum  27 . The toner is selectively held on the surface of the photosensitive drum  27  and is visualized, thereby forming a toner image by an inversion phenomenon. 
         [0035]    Thereafter, the photosensitive drum  27  and the transfer roller  30  are rotationally driven to convey a sheet  3  therebetween. By conveying the sheet  3  between the photosensitive drum  27  and the transfer roller  30 , the toner image held on the surface of the photosensitive drum  27  is transferred to the sheet  3 . 
       &lt;Configuration of Fixing Unit&gt; 
       [0036]    The Fixing unit  18  is disposed on the downstream side of the process cartridge  17  and includes a heating roller  41  and a pressing roller  42  that is opposed to the heating roller  41  so as to press the heating roller  41 . The fixing unit  18  thermally fixes the toner transferred to the sheet  3  while the sheet  3  passes between the heating roller  41  and the pressing roller  42 . The sheet  3  thermally fixed by the fixing unit  18  is conveyed to the discharge roller  45  disposed on the downstream side of the fixing unit  18  and is sent to a sheet discharging tray  46  by the discharge roller  45 . 
       &lt;Structure of Toner Cartridge&gt; 
       [0037]    Next, a detailed structure of the toner cartridge  100  as an example of the developer cartridge according to an embodiment of the invention will be described.  FIG. 2  is a sectional view illustrating a process cartridge according to an embodiment of the invention.  FIG. 3  is a plan view illustrating a toner cartridge.  FIG. 4A  is a sectional view illustrating a relation between a memory chip and a conductive portion when an inner opening and an outer opening are closed,  FIG. 4B  is a sectional view illustrating a relation between the memory chip and the conductive portion when the inner opening and the outer opening communicate with each other, and  FIG. 4C  is a sectional view illustrating a relation among the memory chip, the conductive portion, and a terminal when the toner cartridge is attached to a main casing. 
         [0038]    As shown in  FIG. 2 , the toner cartridge  100  constitutes a process cartridge  17  along with the developing cartridge  28  and the drum unit  51 . And the toner cartridge  100  is detachably attached to the main casing  2  in a state where it is attached to the developing cartridge  28 . Specifically, as shown in FIG.  3 , the toner cartridge  100  includes an inner body  101  that contains a toner T, an outer body  102  that is movable relative to the inner body  101 , and a memory chip  103  as an example of the memory unit disposed between the inner body  101  and the outer body  102 . Here, the memory chip  103  stores a variety of information such as an amount of toner contained in the toner cartridge  100 . The variety of information is read by a reading device disposed in the main casing  28  and is used to perform various control operations for the laser printer  1 . 
         [0039]    The inner body  101  is formed in a hollow cylinder shape and is rotatably supported by a cylindrical inner circumferential surface of the outer body  102 . An inner opening  101   a  for supplying the toner T to the developing cartridge  28  is formed at a far position on a cylindrical outer circumferential surface of the inner body  101 . A flat seat portion  101   b  on which the memory chip  103  is disposed is formed at a far upper position on the cylindrical outer circumferential wall of the inner body  101 . The inner body  101  is fixed to the developing cartridge  28 . 
         [0040]    The outer body  102  is formed in a hollow cylinder shape and an outer opening  102   a  that can communicate with the inner opening  101   a  of the inner body  101  is formed at a far position on a cylindrical outer circumferential wall thereof. A conductive portion  102   b  that can transmit electricity is formed at a far upper position on the cylindrical outer circumferential wall of the outer body  102  from the outer circumferential surface of the outer body  102  to the inner circumferential surface. The conductive portion  102   b  can be connected to a contact terminal  103   a  of the memory chip  103  and a wire-shaped terminal  2   b  disposed in the main casing  2  shown in  FIG. 1  when the inner opening  101   a  of the inner body  101  communicates with the outer opening  102   a  of the outer body  102 . The conductive portion  102   b  can be formed integrally with the outer body  102  by performing an insert molding process on a metal plate having a predetermined shape with a resin. 
         [0041]    As shown in  FIG. 3 , a drive delivery portion  100   c , which is fixed to the right end of a rotation shaft  100   b  of an agitator  100   a  disposed to be rotatable relative to the inner body  101  and the outer body  102 , is disposed on the right end surface of the outer body  102 . When power is supplied to the drive delivery portion  100   c  from the main casing  2  side, the agitator  100   a  rotates. A grip portion  102   e  is disposed on the front side of the outer circumferential surface of the outer body  102 . The grip portion  102   e  is a portion gripped by a user and is formed to protrude forward from the center in the axis direction of the outer body  102 . Since the conductive portion  102   b  is disposed on the left side of the outer body  102 , the grip portion  102   e  is disposed at a position deviating in the axis direction of the agitator  100   a  from the conductive portion  102   b.    
         [0042]    As shown in  FIG. 2 , the memory chip  103  is an example of the memory unit and is fixed to the seat portion  101   b  of the inner body  101  in a state where the contact terminal  103   a  thereof faces the outside in the diameter direction of the inner body  101 . Accordingly, as shown in  FIG. 4A , the contact terminal  103   a  of the memory chip  103  is separated from the conductive portion  102   b , when the inner opening  101   a  and the outer opening  102   a  are closed. And, as shown in  FIG. 4B , the contact terminal  103   a  comes in contact with the conductive portion  102   b , when the inner opening  101   a  communicates with the outer opening  102   a . As shown in  FIG. 3 , while the drive deliver portion  100   c  is disposed at the right end of the rotation shaft  100   b  of the agitator  100   a , the memory chip  103  is disposed at the left end of the rotation shaft  100   b . Accordingly, the vibration of the drive delivery portion  100   c  is hardly transmitted to the memory chip  103 . 
         [0043]    A sealing member S for preventing the movement of toner from the inner opening  101   a  to the memory chip  103  is disposed between the inner body  101  and the outer body  102 , that is, between the memory chip  103  and the inner opening  101   a.    
         [0044]    Next, a relation among the memory chip  103 , the conductive portion  102   b , and the terminal  2   b  disposed on the main casing  2  will be described. 
         [0045]    First, as shown in  FIG. 4A , when the inner opening  101   a  of the inner body  101  and the outer opening  102   a  of the outer body  102  are closed, for example, when the toner cartridge  100  remains as a single product, the contact terminal  103   a  of the memory chip  103  is separated from the conductive portion  102   b . Accordingly, in this state, even when the toner cartridge  100  is attached to the main casing  2  through the developing cartridge  28  or the like, the memory chip  103  is not electrically connected to the terminal  2   b  of the main casing  2 . 
         [0046]    When the grip portion  102   e  is made to move down by a predetermined distance from the state shown in  FIG. 4A , the inner opening  101   a  of the inner body  101  and the outer opening  102   a  of the outer body  102  communicate with each other and the contact terminal  103   a  of the memory chip  103  is connected to the conductive portion  102   b , as shown in  FIG. 4B . Accordingly, as shown in  FIG. 4C , the toner can be supplied from the toner cartridge  100  to the developing cartridge  28  (see  FIG. 2 ) and the memory chip  103  is electrically connected to the terminal  2   b  of the main casing  2  through the conductive portion  102   b.    
         [0047]    According to the above-mentioned embodiment, the following advantages can be obtained. 
         [0048]    Since the memory chip  103  can be protected by the outer body  102  by only disposing the conductive portion  102   b  in the outer body  102 , it is possible to prevent the contamination or damage of the memory chip  103  and to further simplify the device configuration. By electrically connecting the memory chip  103  to the terminal  2   b  of the main casing  2  through the conductive portion  102   b  disposed in the outer body  102 , the memory chip  103  can be always covered with the outer body  102 , thereby protecting the memory chip  103  better. 
         [0049]    When the inner opening  101   a  and the outer opening  102   a  are closed, the contact terminal  103   a  of the memory chip  103  is not electrically connected to the terminal  2   b  of the main casing  2  and thus the laser printer  1  does not work, thereby informing a user that the inner opening  101   a  and the outer opening  102   a  do not communicate with each other. That is, since the information of the memory chip  103  can be read by the laser printer  1  after the inner opening  101   a  and the outer opening  102   a  have communicated with each other so as to supply the toner from the toner cartridge  100  to the developing cartridge  28 , it is possible to suppress an erroneous operation of the laser printer  1 . 
         [0050]    The grip  102   e  is disposed at a position deviating in the axis direction of the agitator  100   a  from the conductive portion  102   b . Accordingly, even when a user handles the toner cartridge  100  with a wet handle, it is possible to prevent the conductive portion  102   b  from getting wet. 
         [0051]    While the drive delivery portion  100   c  is disposed at the right end of the rotation shaft  100   b  of the agitator  100   a , the memory chip  103  is disposed at the left end of the rotation shaft  100   b . Accordingly, the vibration of the drive delivery portion  100   c  is hardly transmitted to the memory chip  103 , thereby elongating the lifetime of the memory chip  103 . 
         [0052]    Since the sealing member S is disposed between the inner body  101  and the outer body  102  and between the memory chip  103  and the inner opening  101   a , it is possible to suppress the contamination of the memory chip  103  due to the toner. 
         [0053]    The invention is not limited to the above-mentioned embodiment, but may be modified in various forms as described below. 
         [0054]    Although it has been described in the embodiment that the inner body  101  is fixed to the developing cartridge  28  and the outer body  102  is made to rotate relative to the inner body  101 , the invention is not limited to the configuration. On the contrary, the outer body  102  may be fixed to the developing cartridge  28  and the inner body  101  may be made to rotate relative to the outer body  102 . Specifically, for example, as shown in  FIG. 5 , a grip portion  101   e  extending to the near side may be disposed on the near side of the center in the axis direction of the inner body  101  and a clearance groove  102   f  permitting the movement of the grip portion  101   e  in the circumferential direction thereof may be disposed at the center in the axis direction of the outer body  102 . In this case, as shown in  FIG. 6A , when the inner opening  101   a  and the outer opening  102   a  are closed, the contact  103   a  of the memory chip  103  can be separated from the conductive portion  102   b . As shown in  FIG. 6B , when the inner opening  101   a  and the outer opening  102   a  communicate with each other, the contact terminal  103   a  of the memory chip  103  can be brought into contact with the conductive portion  102   b  by making the grip portion  101   e  move upward from the state shown in  FIG. 6A  to rotate the inner body  101  relative to the outer body  102 . That is, as shown in  FIG. 6C , when the inner opening  101   a  and the outer opening  102   a  communicate with each other, the contact terminal  103   a  of the memory chip  103  can be connected to the terminal  2   b  of the main casing  2  through the conductive portion  102   b.    
         [0055]    Although it has been described in the embodiment that the memory chip  103  is disposed on the outer circumferential surface of the inner body  101 , the invention is not limited to it, but the memory chip  103  may be disposed on the inner circumferential surface of the outer body  102 . Specifically, for example, as shown in  FIGS. 7 and 8 , the memory chip  103  may be fixed to the inner circumferential surface of the outer body  102  in a state where the contact terminal  103   a  thereof faces the inside in the diameter direction and a conductive portion  102   b ′ formed from the inner circumferential surface of the outer body  102  to the outer circumferential surface may be connected to the contact  103   a . In this structure, the outer body  102  may be made to rotate by means of the operation of the grip portion  102   e  disposed in the outer body  102  as shown in  FIG. 7 , or the inner body  101  may be made to rotate by means of the operation of the grip portion  101   e  disposed in the inner body  101  as shown in  FIG. 8 . According to this structure, since the contact terminal  103   a  of the memory chip  103  is always connected to the conductive portion  102   b ′, the electrical connection between the contact  103   a  of the memory chip  103  and the conductive portion  102   b ′ can be obtained more reliably. 
         [0056]    In the example shown in  FIG. 7 , as shown in  FIGS. 7A and 7C , the conductive portion  102   b ′ can be connected to and disconnected from the terminal  2   b  of the main casing  2  by means of the rotation of outer body  102 . That is, as shown in  FIG. 7A , the conductive portion  102   b ′ is disposed at the position which does not permit the contact with the terminal  2   b  of the main casing  2 , when the inner opening  101   a  and the outer opening  102   a  are closed. As shown in  FIGS. 7B and 7C , the conductive portion  102   b ′ is disposed at a position which can permit the contact with the terminal  2   b  of the main casing  2 , when the inner opening  101   a  and the outer opening  102   a  communicate with each other. Accordingly, in this example, similarly to the above-mentioned embodiment, since the information of the memory chip  103  can be read by the laser printer  1  after the inner opening  101   a  and the outer opening  102   a  have communicated with each other so as to supply the toner from the toner cartridge  100  to the developing cartridge  28 , it is possible to suppress an erroneous operation of the laser printer  1 . 
         [0057]    In comparison with the example shown in  FIG. 7 , since the example shown in  FIG. 8  shows a structure for the inner body  101  relative to the outer body  102 , the conductive portion  102   b ′ is disposed at a position which can always permit the contact with the terminal  2   b  of the main casing  2 , as shown in  FIG. 8C . That is, the conductive portion  102   b ′ can be more reliably brought into contact with the terminal  2   b  of the main casing  2 . 
         [0058]    Although it has been described in the above-mentioned embodiment that the toner cartridge  100  is attached to the main casing  2  in a state where the developing cartridge  28  and the drum unit  51  is incorporated into a bundle, the invention is not limited to the configuration. For example, when the parts of the developing cartridge  28  are fixed to the main casing  2 , the toner cartridge  100  may be attached directly to the main casing  2 . 
         [0059]    Although it has been described in the embodiment that the developing cartridge  28  is freely attached to and detached from the drum unit  51 , the developing cartridge  28  and the drum unit  51  may be formed in a bundle (not separable). 
         [0060]    Although the invention has been applied to the laser printer  1  in the above-mentioned embodiment, the invention is not limited to it, but the invention may be applied to other image forming apparatus such as copiers or multi-function devices. 
         [0061]    Although it has been described in the embodiment that the inner body  101  and the outer body  102  are formed in a hollow cylinder shape and the inner body  101  rotates relative to the outer body  102 , the invention is not limited to it. For example, the inner body and the outer body may be both in a hollow rectangular shape and the inner body and the outer body may be made to move relative to each other along a predetermined side thereof. 
         [0062]    Although it has been described in the above-mentioned embodiment that the toner cartridge  100  contains a positively-charging developer, the toner cartridge may contain a negatively-charging developer.