Sheet finishing apparatus

Abstract

In a sheet finishing apparatus of the present invention, when temporarily loading a plurality of sheets of paper on a standby tray until a processing tray finishes processing, to prevent a sheet of paper loaded first from being pressed out by a sheet of paper ejected later, a chuck for retaining the rear ends of the sheets of paper is installed on the downstream side of the standby tray, and for curled sheets of paper, a standby tray guide and an arm member for suppressing curling of the central part of the sheets of paper are installed, thus matching on the standby tray is stabilized.

1 . A sheet finishing apparatus for post-processing sheets of paper after image forming comprising: 
 a pair of paper supply rollers for receiving and conveying sheets of paper ejected from an image forming apparatus,    a standby tray for making said sheets of paper ejected from said paper supply rollers stand by,    a processing tray arranged under said standby tray for loading said sheets of paper dropped and supplied from said standby tray and/or said sheets of paper ejected from said image forming apparatus not via said standby tray,    a processing mechanism for post-processing said sheets of paper loaded on said processing tray,    a paper ejection tray for loading said post-processed sheets of paper ejected from said processing tray,    a standby tray guide for controlling movement and posture of said sheets of paper ejected from said paper supply rollers to said standby tray, and    an assist arm for pressing rear ends of said sheets of paper ejected from said paper supply rollers against said standby tray.    
   
   
       2 . A sheet finishing apparatus according to  claim 1 , wherein: 
 a chuck for retaining said rear ends of said sheets of paper is installed on the downstream side of said standby tray.    
   
   
       3 . A sheet finishing apparatus according to  claim 1 , wherein: 
 said standby tray guide is born rotatably on a side of said standby tray.    
   
   
       4 . A sheet finishing apparatus according to  claim 1 , wherein: 
 said standby tray guide has a front end rounded so as to crush upward curls of said sheets of paper.    
   
   
       5 . A sheet finishing apparatus according to  claim 1 , wherein: 
 said standby tray guide is arranged left and right of said sheets of paper almost in accordance with a width of said sheets of paper.    
   
   
       6 . A sheet finishing apparatus according to  claim 1 , wherein: 
 said assist arm is born rotatably by a mounting shaft of said paper supply rollers.    
   
   
       7 . A sheet finishing apparatus according to  claim 1 , wherein: 
 said assist arm is in a lever shape.    
   
   
       8 . A sheet finishing apparatus according to  claim 5 , wherein: 
 said assist arm is arranged between said right and left standby tray guides.    
   
   
       9 . A sheet finishing apparatus according to  claim 5 , wherein: 
 a plurality of said assist arms each of a similar or same shape is arranged and said adjacent assist arms are connected mutually.