Sheet buffer with a series of clamping gates

Abstract

A buffer device temporarily retains a number of sheets between a printing apparatus and a finisher, such as a stacker-stapler. The device defines a baffle for the passage of sheets therethrough. Arranged in series in the baffle is a set of gates. Each gate is positionable in an open position or a clamping position that causes a sheet passing nearby to be stopped. By clamping each of a set of sheets as it passes through the baffle, and then setting all the gates to the open position, an accumulated set of sheets can be conveyed out of the baffle substantially simultaneously.

1 . An apparatus, comprising: 
 a baffle, suitable for passage of sheets in a process direction therethrough; and    a first gate and a second gate, disposed within the baffle in series along the process direction, each of the first gate and second gate being positionable in an open position and a clamping position causing a sheet near the gate to be stopped.    
     
     
         2 . The apparatus of  claim 1 , wherein, for the first gate and the second gate, a sheet can pass relative to the gate whether the gate is in the open position or the clamping position.  
     
     
         3 . The apparatus of  claim 1 , further comprising 
 a selectably-engageable drive member, downstream of the baffle along the process direction, capable of effectively contacting a sheet that is stopped by the first gate.    
     
     
         4 . The apparatus of  claim 3 , the selectably-engageable drive member capable of moving at least one sheet out of the baffle.  
     
     
         5 . The apparatus of  claim 3 , the selectably-engageable drive member capable of moving a plurality of sheets out of the baffle substantially simultaneously.  
     
     
         6 . The apparatus of  claim 1 , the first gate being capable of stopping a first sheet and the second gate being capable of stopping a second sheet.  
     
     
         7 . The apparatus of  claim 6 , the first gate being capable of releasing the first sheet and the second gate being capable of releasing the second sheet substantially simultaneously so that the first sheet and second sheet can be moved from the baffle substantially simultaneously.  
     
     
         8 . The apparatus of  claim 7 , wherein, when the first sheet and second sheet are moved from the baffle, the second sheet leads the first sheet.  
     
     
         9 . The apparatus of  claim 1 , the baffle forming a contact surface, and the first gate and the second gate each urging against the contact surface when in the clamping position.  
     
     
         10 . The apparatus of  claim 1 , further comprising 
 a printing apparatus.    
     
     
         11 . The apparatus of  claim 1 , further comprising 
 an electrostatographic image receptor.    
     
     
         12 . The apparatus of  claim 1 , further comprising 
 a finisher.    
     
     
         13 . An apparatus, comprising: 
 a baffle, suitable for passage of sheets in a process direction therethrough; and    a first gate, disposed within the baffle, positionable in an open position and a clamping position causing a sheet near the gate to be stopped, wherein a sheet can pass relative to the first gate whether the first gate is in the open position or the clamping position.    
     
     
         14 . The apparatus of  claim 13 , the baffle forming a contact surface, and the first gate urging against the contact surface when in the clamping position.  
     
     
         15 . The apparatus of  claim 13 , further comprising 
 a selectably-engageable drive member, downstream of the baffle along the process direction, capable of effectively contacting a sheet that is stopped by the first gate.    
     
     
         16 . The apparatus of  claim 15 , the selectably-engageable drive member capable of moving a plurality of sheets out of the baffle substantially simultaneously.  
     
     
         17 . The apparatus of  claim 13 , further comprising 
 a second gate disposed in series with the first gate within the baffle, the second gate being positionable in an open position and a clamping position causing a sheet near the gate to be stopped, wherein a sheet can pass relative to the second gate whether the second gate is in the open position or the clamping position.    
     
     
         18 . The apparatus of  claim 17 , the first gate being capable of stopping a first sheet and the second gate being capable of stopping a second sheet.  
     
     
         19 . The apparatus of  claim 17 , the first gate being capable of releasing the first sheet and the second gate being capable of releasing the second sheet substantially simultaneously so that the first sheet and second sheet can be moved from the baffle substantially simultaneously.  
     
     
         20 . The apparatus of  claim 13 , further comprising 
 an electrostatographic image receptor.