Patent ID: 7866647
Filing Date: 2011-01-11
Classification: B65H

Abstract:
1. A sheet post-processing apparatus to post-process a sheet supplied from an image forming apparatus and delivering it, comprising: a sheet feeding section including a pair of sheet feeding rollers to receive the sheet supplied from the image forming apparatus and conveying it to the downstream side; a stand-by tray to receive the sheet delivered from the sheet feeding section and holding it on a stand-by status; an assist arm arranged on an upper portion of a sheet conveying path so as to project toward the sheet delivery side of the pair of sheet feeding rollers and press from upside the sheet delivered by the sheet feeding roller pair against the standby tray, and adapted to be turned; a motor rotatable both in a first direction and in a second direction opposite to the first direction; an assist arm control section to control the assist arm by utilizing the rotary motion of the motor so as to immobilize the assist arm when the motor is driven to rotate in the first direction but turn the assist arm to press the rear end of the sheet delivered from the sheet feeding roller pair against the stand-by tray when the motor is driven to rotate in the second direction, the assist arm control section controls the assist arm so as to guide and discharge the first sheet, driving the motor to rotate in the first direction, while conveying the first sheet by means of the pair of sheet feeding rollers but press the second sheet, driving the motor to rotate in the second direction, while conveying the second sheet also by means of the pair of sheet feeding rollers; a processing tray arranged below the stand-by tray and adapted to lay the sheet supplied from the image forming apparatus on it; and a post-processing section to post-process the sheet laid on the processing tray.