Sheet Conveying Device

Abstract

A sheet conveying device may include a belt having a plurality of throughholes, a fan disposed so as to interpose a portion of the belt placed in a return run position between the fan and a portion of the belt placed in the forward run position, and a case that defines a chamber with a portion of the belt placed in the forward run position. The fan creates a negative pressure within the chamber by drawing air through the throughholes of the endless belt, thereby removing dust and other unwanted particles and debris from the endless belt. In one or more examples, a brush may also be included to provide further removal of unwanted dust and particles. Further, in one or more configurations, the sheet conveying device may also include belt rollers and/or supporting members.

1 . A sheet conveying device, comprising: 
 an endless belt having a plurality of throughholes passing through in a thickness direction of the belt, a first portion in a forward run position in which the belt conveys a sheet in a sheet conveying direction and a second portion in a return run position opposite to the forward run position;    a fan disposed such that the second portion of the endless belt is located between the fan and the first portion of the endless belt; and    a case that, in conjunction with the first portion of the endless belt, defines a chamber accommodating the second portion of the belt placed in the return run position and the fan,    wherein the fan generates a negative pressure in the chamber causing air to enter the chamber via the plurality of throughholes of the endless belt.    
   
   
       2 . The sheet conveying device according to  claim 1 , wherein the plurality of throughholes are evenly disposed throughout substantially the entire surface of the endless belt.  
   
   
       3 . The sheet conveying device according to  claim 1 , further comprising a support member configured to support the first portion of the endless belt, wherein the supporting member comprises a plurality of platen rollers arranged in the sheet conveying direction, each extending in the same direction as axes of one or more belt rollers and supported by the case so as to rotate in the same direction as the one or more belt rollers.  
   
   
       4 . The sheet conveying device according to  claim 3 , wherein the plurality of platen rollers are equidistantly arranged in the sheet conveying direction.  
   
   
       5 . The sheet conveying device according to  claim 1 , further comprising a support member configured to support the first portion of the endless belt, wherein the supporting member is disposed in the chamber.  
   
   
       6 . The sheet conveying device according to  claim 1 , further comprising a tension roller configured to apply tension to the second portion of the endless belt in the return run position.  
   
   
       7 . The sheet conveying device according to  claim 1 , wherein the case includes an inlet through which the first portion of the endless belt moves to the return run position and an outlet through which the second portion of the endless belt moves to the forward run position.  
   
   
       8 . The sheet conveying device according to  claim 7 , further comprising a brush disposed near the inlet so as to contact a surface of the endless belt.  
   
   
       9 . The sheet conveying device according to  claim 8 , wherein the brush is disposed in the chamber.  
   
   
       10 . The sheet conveying device according to  claim 1 , further comprising a pair of guides configured to press the sheet onto the endless belt, a first guide of the pair of guides being disposed upstream of the forward run position in the sheet conveying direction and a second guide of the pair of guides being disposed downstream of the forward run position in the sheet conveying direction.  
   
   
       11 . The sheet conveying device according to  claim 1 , wherein the chamber comprises a first chamber and a second chamber divided by the second portion of the belt placed in the return run position and wherein the fan is disposed in the second chamber.  
   
   
       12 . The sheet conveying device according to  claim 11 , further comprising a supporting member disposed in the first chamber, the supporting member configured to support the first portion of the endless belt.  
   
   
       13 . The sheet conveying device according to  claim 11 , further comprising a tension roller configured to apply tension to the second portion of the belt placed in the return run position, the tension roller being disposed in the second chamber.