Image forming apparatus and sheet feeding method

Abstract

The present invention has been made to provide an image forming apparatus and a sheet feeding method capable of feeding a sheet without any problem even in the case where the rear end of the sheet is held between separating rollers at the time when the sheet is fed for a transfer process after aligning control. An image forming apparatus comprises a drive controller 101 that controls the drive of feeding rollers disposed on the upstream side in the feeding direction relative to an intermediate feeding roller that feeds a sheet to a regist roller that performs skew correction for the sheet; and a timing determination section 102 that determines the timing at which the regist roller starts feeding the skew corrected sheet after the skew correction. When the timing determination section 102 determines that a predetermined timing for the regist roller to start feeding the skew corrected sheet has come, the drive controller 101 drives the feeding rollers by a predetermined time from the predetermined timing.

1 . An image forming apparatus comprising: 
 a drive controller that controls the drive of feeding rollers disposed on the upstream side in the feeding direction relative to an intermediate feeding roller that feeds a sheet to a regist roller that performs skew correction for the sheet; and    a timing determination section that determines the timing at which the regist roller starts feeding the skew corrected sheet after the skew correction, wherein    when the timing determination section determines that a predetermined timing for the regist roller to start feeding the skew corrected sheet has come, the drive controller drives the feeding rollers by a predetermined time from the predetermined timing.    
     
     
         2 . An image forming apparatus comprising: 
 a drive controller that controls the drive of feeding rollers disposed on the upstream side in the feeding direction relative to an intermediate feeding roller that feeds a sheet to a regist roller that performs skew correction for the sheet;    a sheet size determination section that determines the sheet size in the feeding direction of a sheet to be subjected to the skew correction performed by the regist roller; and    a timing determination section that determines the timing at which the regist roller starts feeding the skew corrected sheet after the skew correction, wherein    in the case where the sheet size determination section determines that a sheet to be subjected to the skew correction performed by the regist roller is larger than a predetermined size, when the timing determination section determines that a predetermined timing for the regist roller to start feeding the skew corrected sheet has come, the drive controller drives the feeding rollers by a predetermined time from the predetermined timing.    
     
     
         3 . The image forming apparatus according to  claim 1 , wherein 
 the predetermined time is a time needed from a predetermined timing to the time for the rear end of a sheet to be released from between the separating rollers in the case where the rear end of the skew corrected sheet is, at the predetermined timing, held between the separation rollers that supply the sheet to the sheet feeding path.    
     
     
         4 . A sheet feeding method comprising: 
 a drive control step that controls the drive of feeding rollers disposed on the upstream side in the feeding direction relative to an intermediate feeding roller that feeds a sheet to a regist roller that performs skew correction for the sheet; and    a timing determination step that determines the timing at which the regist roller starts feeding the skew corrected sheet after the skew correction, wherein    when the timing determination step determines that a predetermined timing for the regist roller to start feeding the skew corrected sheet has come, the drive control step drives the feeding rollers by a predetermined time from the predetermined timing.    
     
     
         5 . A sheet feeding method comprising: 
 a drive control step that controls the drive of feeding rollers disposed on the upstream side in the feeding direction relative to an intermediate feeding roller that feeds a sheet to a regist roller that performs skew correction for the sheet;    a sheet size determination step that determines the sheet size in the feeding direction of a sheet to be subjected to the skew correction performed by the regist roller; and    a timing determination step that determines the timing at which the regist roller starts feeding the skew corrected sheet after the skew correction, wherein    in the case where the sheet size determination step determines that a sheet to be subjected to the skew correction performed by the regist roller is larger than a predetermined size, when the timing determination step determines that a predetermined timing for the regist roller to start feeding the skew corrected sheet has come, the drive control step drives the feeding rollers by a predetermined time from the predetermined timing.    
     
     
         6 . The sheet feeding method according to  claim 4 , wherein 
 the predetermined time is a time needed from a predetermined timing to the time for the rear end of a sheet to be released from between the separating rollers in the case where the rear end of the skew corrected sheet is, at the predetermined timing, held between the separation rollers that supply the sheet to the sheet feeding path.