Sheet compiler for use in a finisher, such as used with a printing apparatus

Abstract

In a high-speed copier or printer, a set of sheets is occasionally withheld while a finisher performs an operation such as compiling and stapling. When the operation of the finisher resumes, a set of buffered sheets is conveyed as a stack into a sloped compiler tray. An upper compiler member, such as a flapper, pushes the top sheet of the stack toward the backstop of the compiler tray, while a lower compiler member pushes the bottom sheet of the stack toward the backstop of the compiler tray. In this way, all of the sheets are aligned against the backstop, such as for stapling.

1 . An apparatus for interacting with sheets, comprising: 
 a sloped compiler tray for receiving sheets;    a backstop at a lower edge of the compiler tray;    an upper compiler member positioned to contact a top sheet retained in the compiler tray, the upper compiler member being movable to convey the top sheet toward the backstop; and    a lower compiler member positioned to contact a bottom sheet retained in the compiler tray, the lower compiler member being movable to convey the bottom sheet toward the backstop.    
     
     
         2 . The apparatus of  claim 1 , further comprising 
 a buffer for conveying a stack of sheets into the compiler tray.    
     
     
         3 . The apparatus of  claim 1 , further comprising 
 a print engine for outputting sheets to the buffer.    
     
     
         4 . The apparatus of  claim 3 , the print engine outputting sheets at a substantially regular frequency.  
     
     
         5 . The apparatus of  claim 1 , further comprising 
 a control system for determining that a stack of sheets are being conveyed to the compiler tray.    
     
     
         6 . The apparatus of  claim 5 , the stack including at least three sheets.  
     
     
         7 . The apparatus of  claim 1 , the upper compiler member including a flapper.  
     
     
         8 . The apparatus of  claim 1 , the lower compiler member including a roll.  
     
     
         9 . The apparatus of  claim 8 , a portion of the roll being disposed through an opening in the compiler tray.  
     
     
         10 . The apparatus of  claim 1 , further comprising 
 a control system to stop moving the lower compiler member to convey the bottom sheet toward the backstop, when the stack of sheets is being ejected from the compiler tray.    
     
     
         11 . The apparatus of  claim 1 , further comprising 
 an electrostatographic print engine for outputting sheets to be conveyed to the buffer.    
     
     
         12 . The apparatus of  claim 1 , further comprising 
 a stapler for stapling sheets in the compiler tray.    
     
     
         13 . A method of interacting with sheets, comprising: 
 providing a sloped compiler tray for receiving sheets and a backstop at a lower edge of the compiler tray;    moving an upper compiler member positioned to contact a top sheet retained in the compiler tray, to convey a top sheet retained in the compiler tray toward the backstop; and    moving a lower compiler member positioned to contact a bottom sheet retained in the compiler tray, to convey the bottom sheet toward the backstop.    
     
     
         14 . The method of  claim 13 , further comprising 
 conveying a stack of sheets into the compiler tray.    
     
     
         15 . The method of  claim 14 , further comprising 
 determining that a stack of sheets are being conveyed to the compiler tray.    
     
     
         16 . The method of  claim 14 , the stack including at least three sheets.  
     
     
         17 . The method of  claim 13 , further comprising 
 stopping moving the lower compiler member to convey the bottom sheet toward the backstop, when the stack of sheets is being ejected from the compiler tray.    
     
     
         18 . The method of  claim 13 , further comprising 
 a print engine outputting sheets at a substantially regular frequency; and    buffering the sheets from the print engine to form a stack of sheets.