Patent ID: 7201370
Filing Date: 2007-04-10
Classification: B65H,Y10S

Abstract:
1. A sheet processing apparatus comprising: a switchback portion configured to receive conveyed sheets and send them in an opposite direction, thereby invert a conveying direction of the sheets; a first detector to detect lengths of the sheets in the conveying direction before being received by the switchback portion; a second detector to detect lengths of the sheets in the conveying direction after being sent from the switchback portion; and a first overlapped sheets detector to detect overlapping of the sheets when detection results of the first and second detectors are different, wherein the switchback portion includes a drive roller, driven to rotate in both forward and backward directions, on one side of the sheets, and a driven roller, following the sheets, in a state that the sheets are held between the drive roller and the driven roller, and wherein the switchback portion is so constructed that: