Sheet post-processing apparatus

Abstract

A sheet post-processing apparatus of the invention includes a sheet switch flapper which divides a sheet delivered from an entrance roller into an upper conveyance path and a lower conveyance path, an upper-surface sheet output tray provided in an end portion of the upper conveyance path, a lower-surface sheet output tray which is provided in an end portion of the lower conveyance path to stack the sheet thereon, the sheet being subjected to post-processing by a post-processing mechanism, a loading sensor which is provided in the upper-surface sheet output tray to detect that a predetermined number of sheets are stacked on the upper-surface sheet output tray, and a changeover mechanism which changes the sheet switch flapper to the lower conveyance path side at the time when the loading sensor detects that the predetermined number of sheets are stacked on the upper-surface sheet output tray.

1 . A sheet post-processing apparatus comprising: 
 an entrance roller which receives and conveys a sheet conveyed from an MFP main body;    a sheet switch flapper which divides the sheet delivered from the entrance roller into an upper conveyance path and a lower conveyance path;    an upper-surface sheet output tray which is provided in an end portion of the upper conveyance path to stack the sheet delivered from the entrance roller thereon when post-processing is not performed;    a post-processing mechanism which is provided in the lower conveyance path to perform the post-processing to the sheet delivered from the entrance roller when the post-processing is performed;    another tray which is provided in an end portion of the lower conveyance path to stack the sheet thereon, the sheet being subjected to the post-processing by the post-processing mechanism;    an upper-surface sheet output tray loading sensor which is provided in the upper-surface sheet output tray to detect that a predetermined number of sheets are stacked on the upper-surface sheet output tray; and    a changeover mechanism which changes the sheet switch flapper to the lower conveyance path side at the time when the upper-surface sheet output tray loading sensor detects that the predetermined number of sheets are stacked on the upper-surface sheet output tray.    
   
   
       2 . A sheet post-processing apparatus according to  claim 1 , wherein the lower conveyance path is formed longer than the upper conveyance path.  
   
   
       3 . A sheet post-processing apparatus according to  claim 1 , wherein a time in which the sheet passes through the lower conveyance path is longer than a time in which the sheet passes through the upper conveyance path.  
   
   
       4 . A sheet post-processing apparatus comprising: 
 conveyance means for receiving and conveying a sheet conveyed from an MFP main body;    sheet switch means for dividing the sheet delivered from the conveyance means into an upper conveyance path and a lower conveyance path;    an upper-surface sheet output tray which is provided in an end portion of the upper conveyance path to stack the sheet delivered from the conveyance means thereon when post-processing is not performed;    post-processing means provided in the lower conveyance path, the means performing the post-processing to the sheet delivered from the conveyance means when the post-processing is performed;    another tray which is provided in an end portion of the lower conveyance path to stack the sheet thereon, the sheet being subjected to the post-processing by the post-processing means;    upper-surface sheet output tray loading means provided in the upper-surface sheet output tray, the means detecting that a predetermined number of sheets are stacked on the upper-surface sheet output tray; and    changeover means for changing the sheet switch means to the lower conveyance path side at the time when the upper-surface sheet output tray loading means detects that the predetermined number of sheets are stacked on the upper-surface sheet output tray.    
   
   
       5 . A sheet post-processing apparatus according to  claim 4 , wherein the lower conveyance path is formed longer than the upper conveyance path.  
   
   
       6 . A sheet post-processing apparatus according to  claim 4 , wherein a time in which the sheet passes through the lower conveyance path is longer than a time in which the sheet passes through the upper conveyance path.  
   
   
       7 . A sheet post-processing method comprising: 
 receiving and conveying a sheet conveyed from an MFP main body;    dividing the delivered sheet into an upper conveyance path and a lower conveyance path;    stacking the delivered sheet at an end portion of an upper conveyance path when post-processing is not performed;    performing the post-processing to the delivered sheet in the lower conveyance path when the post-processing is performed;    stacking the sheet subjected to the post-processing on another tray at an end portion of the lower conveyance path;    detecting that a predetermined number of sheets are stacked on the upper-surface sheet output tray with an upper-surface sheet output tray loading sensor provided in the upper-surface sheet output tray; and    changing a sheet switch flapper to the lower conveyance path side at the time when the upper-surface sheet output tray loading sensor detects that the predetermined number of sheets are stacked on the upper-surface sheet output tray.