Sheet processing apparatus and sheet processing method

摘要

A sheet processing apparatus of the invention includes a post-processing unit that applies post-processing to sheets conveyed from an image forming apparatus, a vertical aligning unit that conveys the sheets to the post-processing unit and brings an edge of the sheets into contact with a movable stopper arranged in a conveying path for the sheets to align the sheets in a conveying direction, and a horizontal aligning unit that holds the sheets with a pair of movable aligning plates from both sides along the conveying direction to align the sheets in a direction orthogonal to the conveying direction. The sheet processing apparatus further includes a control unit that switches a position of the stopper according to a size of the sheets and controls the aligning plates to be located on both sides close to the center of the sheets when the sheets are brought into contact with the stopper. The post-processing unit applies the post-processing to the sheets aligned.