Sheet collecting device, post-processing apparatus and image forming apparatus

Abstract

Providing a sheet collecting device capable of being downsized and of operating stably wherein a sheet ejecting device that conveys and ejects a sheet in the direction for making the sheet fall along a slanted sheet collecting board is provided, and a leading edge stopper that holds sheets on the sheet collecting board is set so that a trailing edge of the sheet may be at a constant height independently of a sheet size.

1 . A sheet collecting device comprising:
 a sheet collecting board including a sheet supporting surface which is inclined so that an upstream side thereof in a sheet conveyance direction when a sheet is carried in is higher than a downstream side thereof;   an ejecting device which is positioned upstream of the sheet collecting board and which ejects the sheet on the sheet collecting board by conveying the sheet in a direction so that the sheet falls along the sheet collecting board;   a leading edge stopper which stops the sheet on the sheet collecting board;   a stopper moving device which changes a position of the leading edge stopper; and   a control device which controls the stopper moving device so that a position of a trailing edge of the sheet when the sheet is carried in on the sheet collecting board is constant regardless of a difference of a size of the sheet.   
     
     
         2 . The sheet collecting device of  claim 1 ,
 wherein the control device controls the stopper moving device based on sheet size information.   
     
     
         3 . The sheet collecting device of  claim 1 ,
 wherein the ejecting device has an ejection exit for ejecting the sheet and the position of the trailing edge of the sheet on the sheet collecting board is lower than a position of the ejection exit.   
     
     
         4 . A post-processing apparatus comprising:
 the sheet collecting device of  claim 1 ;   a stapler which staples sheets on the sheet collecting board, the sheets having been collected on the sheet collecting board,   wherein the control device controls the stopper moving device so as to move and set the leading edge stopper at a second stop position after setting the leading edge stopper at a first stop position for collecting the sheets and   wherein the stapler staples the sheets supported by the leading edge stopper set at the second stop position.   
     
     
         5 . A post-processing apparatus comprising:
 the sheet collecting device of  claim 1 ;   a folding device which folds the sheet having been collected on the sheet collecting board,   wherein the control device controls the stopper moving device so as to move and set the leading edge stopper at a third stop position after setting the leading edge stopper at a first stop position for collecting the sheet and   wherein the folding device folds the sheet supported by the leading edge stopper set at the third stop position.   
     
     
         6 . The post-processing apparatus of  claim 4  comprising:
 a gripping member which grips the sheets,   wherein when the leading edge stopper moves while supporting the sheets, the control device controls the stopper moving device and the gripping member so that the leading edge stopper moves after the gripping member grips the sheets.   
     
     
         7 . The post-processing apparatus of  claim 5  comprising:
 a gripping member which grips the sheet,   wherein when the leading edge stopper moves while supporting the sheet, the control device controls the stopper moving device and the gripping member so that the leading edge stopper moves after the gripping member grips the sheet.   
     
     
         8 . An image forming apparatus comprising:
 an image forming apparatus main body which forms an image on a sheet; and   the sheet collecting device of  claim 1  which collects the sheet on which the image is formed by the image forming apparatus main body.