Patent ID: 7052005
Filing Date: 2006-05-30
Classification: B65H

Abstract:
1. A sheet postprocessing apparatus which executes postprocessing including a folding process for a sheet on which an image is transferred/formed by an image forming apparatus, comprising a sheet folding section having first and second folding sections which are arranged in series in a sheet convey direction to execute the folding process for the sheet, the first folding section having a first folding path for folding the sheet and a first through path for not folding, and the second folding section having a second folding path for folding the sheet and a second through path for not folding, wherein said sheet folding section is configured such that the first folding section performs a first folding process in a Z-fold process, a first folding process in an internal three-fold process, and a center folding process, wherein the second folding section performs a second folding process in the Z-fold process, a second folding process in the internal three-fold process, and wherein each of the first and second folding sections comprises a pair of folding rollers which rotate in tight contact with each other, an upstream driven roller which is detachably brought into tight contact with one of the pair of folding rollers to be driven/rotated, a downstream driven roller which is brought into tight contact with the other of the pair of folding rollers to be driven/rotated, and a sensor which detects passage of a leading end portion of a sheet guided into the folding section.