Jammed sheet reverse using active retard feeder

Abstract

A fully active retard feeder is configured to move a partially feed sheet back into a feed tray in response to a jam either in the nip of the feed head or in a location downstream of the feed head and thereby ease user jam clearance.

What is claimed is: 
     
         1 . A media transport jam clearance system for engaging a media sheet fed from a stack of media sheets and returning the engaged sheet to the media stack, the system comprising:
 a feed roll, carried on a feed roll shaft adjacent the stack;   a retard roll, carried on a retard roll shaft, the retard roll being loaded against the feed roll to create a feed nip lying in a media transport path;   a nudger roll, carried on a nudger roll shaft positioned above the media stack;   a drive motor operatively coupled to the drive roll shaft, retard roll shaft and the nudger roll shaft;   a feed clutch engageably coupling the feed roll shaft to drive the feed roll shaft in a feed direction to propel media sheets from the media stack to the media transport path;   a slip clutch engageably coupling the retard roll shaft to drive the retard roll shaft in a direction opposite the feed direction, the slip clutch breakaway torque being below the torque imposed by the media sheet; and   wherein, in a clear jam state, the feed clutch is disengaged from the feed roll shaft and the nudger roll shaft, and the slip clutch is engaged to the retard roll shaft to rotate the retard roll and drive the sheet in the direction opposite the feed direction.   
     
     
         2 . The media transport jam clearance system of  claim 1 , operable in a multiple sheet jam state, wherein, in the multiple sheet jam state, when the media transport jam clearance system engages two or more sheets, the slip clutch breakaway torque being more than the load imposed by two or more media sheets, the feed clutch is disengaged from the feed roll shaft and the slip clutch is engaged to the retard roll shaft to rotate the retard roll and drive the sheets in the direction opposite the feed direction. 
     
     
         3 . The media transport jam clearance system of  claim 1 , wherein said nudger roll is configured to move between a raised position out of contact with the media stack and a nudging position in contact with the topmost sheet in the media stack. 
     
     
         4 . (canceled) 
     
     
         5 . (canceled) 
     
     
         6 . The media transport jam clearance system of  claim 3 , wherein the feed clutch engageably couples the nudger roll shaft. 
     
     
         7 . The media transport jam clearance system of  claim 6 , wherein, in the clear jam state, the feed clutch is disengaged from the nudger roll shaft. 
     
     
         8 . The media transport jam clearance system of  claim 6 , operable in a multiple sheet jam state, wherein, in the multiple sheet jam state, the feed clutch is engaged to the nudger roll shaft. 
     
     
         9 . (canceled) 
     
     
         10 . A method for transporting media in a media transport path in a clear jam state, comprising:
 providing a media transport jam clearance system for engaging a single media sheet partially fed from a stack of media sheets and returning the engaged partially fed single media sheet to the media stack in response to a downstream jam in said media transport path, said media transport clearance system including: a feed roll carried on a feed roll shaft adjacent said stack; a retard roll carried on a retard roll shaft, said retard roll being loaded against said feed roll to create a feed nip lying in said media transport path; a feed clutch engagably coupling said feed roll shaft to drive said feed roll shaft in a feed direction to propel media sheets from said media stack to said media transport path; and a slip clutch engageably coupling said retard roll shaft to drive said retard roll shaft in a direction opposite said feed direction, the slip clutch having a breakaway torque being below the load imposed by said media sheet;   disengaging said feed clutch from said feed roll shaft; and   engaging said slip clutch to said retard roll shaft to rotate said retard roll and drive said single media sheet in the direction opposite the feed direction.   
     
     
         11 . The method of  claim 10  for transporting media in a multiple sheet jam state, wherein, in said multiple sheet jam state, when said media transport jam clearance system engages two or more media sheets, said slip clutch breakaway torque being more than the load imposed by two or more media sheets, the method further comprising:
 engaging said feed clutch to said feed roll shaft; and 
 engaging said slip clutch to said retard roll shaft to rotate said retard roll and drive said media sheet in the direction opposite the feed direction. 
 
     
     
         12 . The method of  claim 10 , wherein the media transport jam clearance system further includes a nudger roll, carried on a nudger roll shaft positioned above said media stack and configured to move between a raised position out of contact with said media stack and a nudging position in contact with the topmost sheet in said media stack. 
     
     
         13 . The method of  claim 12 , wherein the media transport jam clearance system further includes a drive motor operatively coupled to said nudger roll shaft. 
     
     
         14 . The method of  claim 12 , further comprising raising said nudger roll out of contact with said media stack. 
     
     
         15 . The method of  claim 12 , wherein said feed clutch engageably couples said nudger roll shaft. 
     
     
         16 . The method of  claim 15 , further comprising disengaging said feed clutch from said nudger roll shaft. 
     
     
         17 . The method of  claim 15  for transporting media in a multiple sheet jam state, wherein, in said multiple sheet jam state, the method further comprising engaging said feed clutch to said nudger roll shaft. 
     
     
         18 . The method of  claim 10 , including feeding a partially fed single sheet caught between said feed roll and retard roll back into said stack in response to a misfeed. 
     
     
         19 . The media transport jam clearance system of  claim 1 , wherein said feed roll is adapted to freewheel when a jam is detected within a nip formed between said feed roll and retard roll. 
     
     
         20 . The media transport jam clearance system of  claim 1 , wherein said feed roll is adapted to freewheel when a jam is detected downstream of said media stack.