Abstract:
A feeding path with opposing guide members. One of the guide members is divided into a plurality of parts in a sheet width direction. The parts selectively open and close portions of the feeding path. The parts move in a space where a sheet processing device moves.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a sheet stacking and aligning device for aligning and stacking sheets, a sheet processing apparatus comprising the sheet stacking and aligning device, and an image forming apparatus comprising the sheet processing apparatus. 
   2. Description of the Related Art 
   Conventionally, for reducing the occupied area at the time of installing an image forming apparatus and a sheet processing apparatus in the sheet processing apparatus connected with the image forming apparatus such as a printing apparatus, a copying machine, and a printer, there is an image forming apparatus system comprising a sheet processing apparatus  500  between an image forming apparatus main body  200  (printer part) and an original reading device  150  as shown in  FIG. 13 . 
   According to the image forming apparatus system, a sheet S with an image formed by the image forming apparatus main body  200  is stacked temporarily on a processing tray  540  in the sheet processing apparatus  500  so as to execute the sheet process such as the aligning and binding process for the sheets S, or the like thereat. Thereafter, they are discharged to a stack tray  581  having an inclined stacking surface as shown in  FIG. 13  by a bundle discharging means  580 . The discharged sheets S are moved on the inclined stacking surface of the stack tray by their self weight so as to have the sheet rear end aligned by the rear end aligning wall. The number of the stacked sheets depends on the width of the vertically movable stroke of the stack tray  581 . 
   Moreover, according to another sheet processing apparatus  500  connected with the image forming apparatus, for changing the binding position in the binding process to be executed by the sheet processing apparatus according to the paper size of the sheet S discharged from the image forming apparatus, the image orientation, the mode set by the user, or the like, a stapler for executing the binding process can be moved. 
   In contrast, in the case the sheet is choked in the feeding path  510  of the sheet processing apparatus  500 , a left door  210  of the image forming apparatus main body  200  is opened in the arrow X direction of  FIG. 13  and the upper feeding guide  501  of the sheet processing apparatus  500  is opened in the arrow Y direction for eliminating the choked sheet. 
   However, in the case the sheet is choked in the feeding path  510  of the sheet processing apparatus  500 , since the choked sheet is eliminated by opening the upper feeding guide  501  of the sheet processing apparatus  500  in the arrow B direction, a problem is involved in that an space for opening the upper feeding guide  501  is required in the upper part of the upper feeding guide  501 . 
   Moreover, since the number of sheets to be stacked on the sheet processing apparatus  500  depends on the vertical movable stroke of the stack tray  581 , for enlarging the number of sheets to be stacked, the sheet processing apparatus should be shifted upward for enlarging the vertical movable stroke of the stack tray  581 . 
   Therefore, in order to provide the space for eliminating the sheets choked in the feeding path  510  and enlarging the number of sheets to be stacked-on the stack tray  581 , a problem is involved in that the entire apparatus becomes bulky and the cost is increased. 
   SUMMARY OF THE INVENTION 
   Accordingly, an object to the present invention is to provide a sheet processing apparatus capable of ensuring the space for eliminating choked sheets, and realizing the miniaturization of the apparatus while achieving a large amount of the sheets to be stacked. 
   In order to solve the above-mentioned problems, a representative configuration of the sheet processing apparatus according to the present invention comprises a stacking means for stacking sheets fed from an image forming apparatus main body, a feeding path comprising guide members for feeding the sheets to the stack means, disposed facing with each other, a discharging means for discharging the sheets to the stack means, and a sheet processing means for processing a sheet bundle stacked on the stack means at a predetermined position, wherein one of the guide members disposed facing with each other is divided in the sheet width-direction so as to be selectively opened or closed in a space where the sheet-processing means moves. 
   Since one of the guide members disposed facing with each other is divided so as to be opened, the eliminating processing space for eliminating a sheet choked in the feeding path of the sheet processing apparatus can be ensured so that the operability can be improved. Moreover, since one of the feeding rollers is supported by the divided guide member and the other feeding roller provided to the facing guide member is forced per the divided guide member, the feeding roller can be pressured evenly so that obliqueness of the sheet generated by the uneven feeding roller pressure can be prevented. 
   Moreover, since the guide member divided in the sheet width direction can be opened or closed in the space for moving the processing means, the miniaturization of the apparatus can be realized while achieving a large number of the sheets to be stacked without the need of additionally providing a rotating space for the divided guide members. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a cross sectional view of an image forming apparatus according to an embodiment; 
       FIG. 2  is a cross sectional view of a sheet processing apparatus; 
       FIG. 3  is a cross sectional view of a sheet processing apparatus; 
       FIG. 4  is an essential part cross sectional view of a sheet processing apparatus; 
       FIG. 5  is a perspective view of a feeding path of a sheet processing apparatus; 
       FIG. 6  is a diagram showing the positional relationship between a feeding roller and a spring provided in a divided feeding guide of a sheet processing apparatus; 
       FIG. 7  is a diagram for explaining an operation for eliminating a sheet choked in the feeding path of a sheet processing apparatus; 
       FIG. 8  is a diagram showing the positional relationship between a divided guide and a stapler at the time of eliminating a sheet choked in the feeding path of a sheet processing apparatus; 
       FIG. 9  is a diagram showing the positional relationship between a divided guide and a stapler at the time of eliminating a sheet choked in the feeding path of a sheet processing apparatus; 
       FIG. 10  is a diagram showing the positional relationship between a divided guide and a stapler at the time of eliminating a sheet choked in the feeding path of a sheet processing apparatus; 
       FIG. 11  is a diagram showing the positional relationship between a divided guide and a stapler at the time of eliminating a sheet choked in the feeding path of a sheet processing apparatus; 
       FIG. 12  is a diagram showing the positional relationship between a divided guide and a stapler at the time of eliminating a sheet choked in the feeding path of a sheet processing apparatus; and 
       FIG. 13  is a cross sectional view showing the entire configuration of the conventional sheet processing apparatus. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   An embodiment of a sheet processing apparatus according to the present invention will be explained with reference to the drawings.  FIG. 1  is a cross sectional view of an image forming apparatus main body  200  with a sheet processing apparatus  500  according to this embodiment mounted, and  FIGS. 2 ,  3  are cross sectional views of the sheet processing apparatus  500 . 
   (Entire Configuration) 
   As shown in  FIG. 1 , the image forming apparatus system comprises an original reading device  150 , the image forming apparatus main body  200  and the sheet processing apparatus  500 . 
   The sheet processing apparatus  500  provided above the image forming apparatus main body  200  and below the original feeding device  100 , comprises a sheet stacking and aligning device. The sheets S with an image formed, and discharged from the image forming apparatus main body  200  are stacked temporarily on the processing tray  540  as the stack means, and after the process of stabling, aligning, or the like, they are aligned and stacked on the stack tray  570  provided substantially horizontally by the sheet stacking and aligning device. 
   The sheet stacking and aligning device can be one to be connected directly with the image forming apparatus main body  200  without the processing tray  540 , or the sheet processing apparatus  500  can be one to be mounted outside the image forming apparatus main body  200 . 
   The original reading device  150  has the automatic original feeding device  100  mounted above. The automatic original feeding device  100  separates above the originals set upwardly for feeding one by one successively from the top page in the leftward direction, feeds the same onto a platen glass  102  via a curved path, and discharges the same onto the discharging tray  112  after reading the originals. 
   By directing a light beam of an unshown lamp of the scanner unit  104  to the original, and guiding the light beam reflected from the original to an image sensor  109  via mirrors  105 ,  106 , and a lens  107 , the original can be read out. The original image read by the image sensor  109  has the image process applied so as to be sent to an exposure controlling part  202  of the image forming apparatus main body  200 . 
   The exposure controlling part  202  directs a laser beam by the image information from the original reading device  150  onto a photosensitive drum  203  with the surface uniformly charged, to be an image forming means for forming an electrostatic latent image. The electrostatic latent image formed on the photosensitive drum  203  is developed by a developing device  205 , and then it is transferred onto the intermediate transfer belt  211  as a toner image. 
   In contrast, the sheets S are picked up optionally and selectively from sheet cassettes  231 ,  232  by a pick up roller  238  comprising the sheet feeding means, and separated by a separating means  237  so as to be fed one by one. After correcting the obliqueness by the resist front roller pair, they are sent to a transfer position synchronously with the rotation of the intermediate transfer belt  211  so that the toner images formed on the intermediate transfer belt  211  are transferred onto the sheets S. 
   Thereafter, the sheets S are guided by the firing roller pair  206  so that the toner images transferred on the sheets S are fixed permanently by applying the heating and pressuring process by the firing roller pair  206 . The sheets S with the toner images fixed are guided to the sheet processing apparatus  500  connected with the image forming apparatus main body  200  by the discharging roller pair  207 . 
   (Sheet Processing Apparatus) 
   The sheet processing apparatus  500  comprises a processing tray  540  as a sheet stack means disposed on the sheet feeding direction upstream side, and a stack tray  570  disposed substantially horizontally on the downstream side vertically movably. The sheet processing apparatus  500  applies the sheet process such as the stapling process and the aligning process to the sheets S discharged from the discharging roller pair  207  of the image forming apparatus main body  200  by the processing tray  540  so as to stack the same on the stack tray  570 . 
   The modes for the sheet process executed by the processing tray  540  include a sorting mode for sorting a plurality of sheets, a stapling mode for stapling a plurality of sheets by a stapler  560 , or the like, and they are selected and set by an unshown setting means. Furthermore, the stapling position such as a one position stapling mode and a two position stapling mode can be selected so that the selected stapling process can be executed by moving the stapler  560  to the real stapling position depending on the setting content such as the sheet size and the binding position. 
   As shown in  FIG. 2 , the sheets S discharged from the image forming apparatus  200  are fed by the feeding roller  511  provided as the discharging means in the feeding path  510  of the sheet processing apparatus  500 , the feeding roller  512  driven thereby, and the discharging roller pair  513 . In the case the rear end of the sheets S passes by the rear end detecting sensor  514 , the sheet rear end is discharged by a predetermined speed from the discharging roller pair  513 . 
   As shown in  FIG. 2A , at the timing with the sheet S rear end passes by the discharging roller pair  513 , the sway arm  520  with one end supported rotatably is swayed in the arrow A direction so as to be supported rotatably by the other end of the sway arm  520 , nipped by the sway roller  521  to be rotated and driven by an unshown driving source and the driven roller  522  driven thereby, and sent to the sheet rear end stopper  541   
   As shown in  FIG. 2B , the sheet S sent to the sheet rear end stopper  541  is released from the nip of the sway roller  521  and the driven roller  522  according to swaying of the sway arm  520  in the arrow B direction. The sheet S released from the nip is butted against the sheet rear end stopper  541  by a return belt  542  so as to align in the sheet feeding direction. Thereafter, the sheets S are aligned in the sheet width direction by an aligning plate  550  movable in the sheet width direction orthogonal to the sheet feeding direction. The aligning plate  550  may be disposed either on one side in the width direction of the sheet S or at two positions on the both sides in the width direction of the sheet S. At the time, in the case the processing tray  540  is a substantially horizontal tray, since the alignment in the sheet feeding direction may be disturbed at the time of the alignment by the aligning plate  550 , the alignment is executed again by the return belt  542  in the feeding direction. 
   After finishing the alignment of a predetermined number of the sheets, in the case the stapling mode is selected by the operating part, the stapler  560  as the sheet processing means staples at the binding position designated by the operating part. Thereafter, as shown in  FIG. 3A , the sway arm  520  is swayed in the arrow A direction so as to rotate the sheet bundle S with the binding process in a state clamped by the sway roller  521  and the driven roller  522  in the arrow C direction for discharging the sheet bundle with the binding process onto the stack tray  570  After discharging the sheet bundle, as shown in  FIG. 3B , the sway arm  520  is swayed in the arrow B direction for preparing for the subsequent sheet process and alignment. 
   Next, the configuration of the feeding path  510  of the sheet processing apparatus will be explained with reference to  FIGS. 4 ,  5 . The feeding path  510  comprising an upper feeding guide  501  as a guiding member, a lower feeding guide  502 , and a divided feeding guide  503 , is provided above the stapler  560 . 
   The divided feeding guide  503  ( 503   a ,  503   b ,  603   c ,  503   d ) is divided in four parts in the sheet width direction. The feeding roller  511  is supported rotatably on the upper feeding guide  501 , and the driven roller  512  is supported by the divided feeding guides  503   b  and  503   c  according to the contact with the feeding roller  511 . 
   The parts  503   a ,  503   b ,  503   c ,  503   d  of the divided feeding guide  503  are interlocked with the lower feeding guide  502  each via a hinge  504  so as to be opened or closed downwardly with the hinge  504  as the fulcrum. A spring  505  is wound around each on the hinge  504 , and the divided feeding guide  503  is forced to the upper feeding guide  501  side by the spring  505 . 
   Moreover, as shown in  FIG. 6 , since the springs  505  are disposed in the central two parts  503   b ,  503   c  of the divided feeding guide  503  from the width direction center of the driven roller  512  at equal interval positions, compared with the case of providing the feeding guide integrally, the pressuring force between the driven roller and the feeding roller cannot be influenced by the tilt of the feeding guide by the mounting error, or the like so that the driven roller  512  can be forced by an even pressuring force with respect to the feeding roller  511 . 
   Next, the operation of eliminating the sheet S in the case the sheet S is choked in the feeding path  510  will be explained. As shown in  FIG. 7 , the right door  200   a  (the parts marked by the slant lines in  FIG. 7 ) of the image forming apparatus main body  200  is opened for eliminating the sheet S. Since the configuration of  FIG. 7  differs from the configuration of the image forming apparatus of  FIG. 1  only by the right door  200   a , explanation is omitted for the other same parts. 
     FIGS. 8 to 12  show the positional relationship of the stapler  560  and the divided feeding guide  503  in a state with the right door  200   a  ( FIG. 7 ) opened.  FIG. 8  shows the state of binding the sheets stacked on the processing tray at one point on the front side,  FIG. 9  the state of binding the sheets stacked on the processing tray at one point on the deeper side,  FIG. 10  the state of binding the sheets stacked on the processing tray at two points on the front side,  FIG. 11  the state of binding the sheets stacked on the processing tray at one point on the deeper side, and  FIG. 12  the state of executing a processing mode other than the above-mentioned. 
   As shown in  FIGS. 8 to 12 , at least one of the divided feeding guide  503  can be opened or closed downwardly. Accordingly, by opening the divided feeding guide  503  downwardly, the sheet S choked in the feeding path  510  can be confirmed visually, and by opening the divided feeding guide  503  downwardly further widely, the workability for eliminating the sheet S choked in the feeding path  510  can be improved. 
   As mentioned above, by dividing the divided feeding guide  503 , the feeding roller  511 , and the feeding roller  512  can be pressured evenly so that the obliqueness of the sheets derived from the uneven pressure of the feeding roller  511  and the feeding roller  512  can be prevented. Moreover, since the divided feeding guide  503  can be opened and closed so that the eliminating processing space for eliminating the sheet choked in the feeding path of the sheet processing apparatus can be ensured, the workability can be improved. 
   Moreover, since the divided feeding guide  503  can be opened and closed in the moving space of the stapler  560  of the sheet processing apparatus  500 , the stapler  560  moving space can be utilized as the rotating space of the divided feeding guide  503  so that the rotating space of the divided feeding guide  503  for the jamming process needs not be provided additionally, and as a result, the space can be saved for the entire sheet processing apparatus  500 . 
   Moreover, also as to the workability, since at least one of the divided feeding guides  503  can be opened without interference with the stapler  560  regardless of the position of the stapler  560 , the visual confirming property of the sheet choked in the feeding path  510  of the sheet processing apparatus  500  can be improved. 
   Moreover, since at least one of the divided feeding guides  503  without interference with the stapler  560  can be downwardly opened widely regardless of the position of the stapler  560 , the stapler  560  needs not be moved to a position without disturbing the process before the eliminating process for the sheet choked in the feeding path  510  of the sheet processing apparatus  500  so that the eliminating processing time for the choked sheet can be shortened. 
   Although an example of dividing the guide member  503  into the four parts has been explained in this embodiment, the number of dividing the guide member  503  is not limited thereto, and two or more numbers can be selected optionally. 
   Although the structure of opening the feeding path  510  by providing the parts  503   a ,  503   b ,  503   c ,  503   d  rotatably around one end has been explained in this embodiment, the feeding path  510  can be opened not only by this structure, and a movable structure of the guide member  503  for taking out the jammed sheet S per each part  503   a ,  503   b ,  503   c ,  503   d , or a detachable structure can be used as well. 
   Moreover, although the divided structure with the lower feeding guide member to be opened has been explained in this embodiment, a divided structure with the upper feeding guide member to be opened can be used as well. 
   Furthermore, although an example of the stapler for executing a binding process of a sheet bundle has been explained as the sheet processing means, it is not limited thereto, and it is needless to say that the same effect an be obtained by a punching means for applying a punching process to the sheets as the sheet processing means, a book binding means such as a gluing means for gluing on the sheet bundle end part, or a tape adhering means for adhering a binding tape on the sheet bundle end part.