Patent ID: 7896334
Filing Date: 2011-03-01
Classification: B42C,B65H

Abstract:
1. A sheet post-processing apparatus comprising: a processing tray that receives sheets subjected to image formation from an image forming apparatus; a sheet discharge tray that stacks the sheets discharged after processing in a post process; and a sheet aligning device having: a first sheet aligning device that includes a stopper, which stops the sheets, and a rotor having a paddle provided radially with respect to a rotation axis, rotates the paddle to draw in the sheets, and strikes the sheets against the stopper, thereby aligning the sheets in a conveying direction, a second sheet aligning device that aligns the sheets in a direction perpendicular to the conveying direction, and a control unit that controls aligning operations of the first sheet aligning device and the second sheet aligning device and increases, in subjecting the sheets to staple processing, when a number of the sheets conveyed thereto exceeds a predetermined number, a number of times of the aligning operation of the first sheet aligning device to be larger than a number of times of the aligning operation at a number of sheets equal to or smaller than the predetermined number of sheets.