Sheet processing apparatus, image forming system, and sheet processing method

摘要

A sheet processing apparatus (PD) includes: a sheet stacking unit (F) on which sheets are accommodated and stacked as a sheet bundle (SB); an aligning member (51a,51b) that is movable along a trailing end, in a conveying direction, of the sheet bundle (SB) stacked on the sheet stacking unit (F) and that aligns the trailing end of the sheet bundle (SB) in the sheet conveying direction by abutting thereon; a binding unit (S1) that moves along the trailing end of the sheet bundle (SB) in the sheet conveying direction and binds the aligned sheet bundle (SB); and a moving unit (55) that moves the aligning member (51a) in the sheet conveying direction. A distance from the trailing end of the sheet bundle (SB) in the sheet conveying direction to a binding position is adjusted by moving the aligning member (51a) in the sheet conveying direction.