Patent ID: 7891651
Filing Date: 2011-02-22
Classification: B65H

Abstract:
1. A post-processing apparatus comprising: a conveyance unit including (i) a stacker for storing a plurality of sheets placed one on top of another, and (ii) a first conveyance path having a curvature for conveying the plurality of sheets placed one on top of another in the stacker in a sheet conveyance direction while the plurality of sheets are placed one on top of another; a second conveyance path connected with the first conveyance path and located downstream of the conveyance unit in the sheet conveyance direction; a stopper which is located downstream of the conveyance unit in the sheet conveyance direction and which is swingable for aligning edges of the plurality of sheets placed one on top of another by making contact with the edges; a conveyance roller which is rotatable both in a forward and reverse direction and which is provided downstream of the stopper in the sheet conveyance direction; a punching section for punching the plurality of sheets whose edges are kept in contact with the stopper; and a control section for controlling operation of the stopper, the conveyance roller, and the punching section; wherein the control section: (i) controls the conveyance roller to convey and stop the plurality of sheets placed one on top of another at a position where a trailing edge of an outside sheet among the plurality of sheets is positioned upstream of a regulating position of the stopper in the sheet conveyance direction and a trailing edge of an inside sheet among the plurality of sheets is positioned downstream of the regulating position of the stopper in the sheet conveyance direction, (ii) then controls the stopper to swing to be moved to a closed position where the stopper closes the second conveyance path and to push the trailing edge of the outside sheet to be moved to the regulating position, (iii) then controls the conveyance roller to rotate reversely to send the inside sheet in an opposite direction to the sheet conveyance direction so as to bring the trailing edge of the inside sheet into contact with the stopper for positioning at the regulating position, and (iv) then controls the punching section to punch a trailing edge side of the plurality of sheets placed one on top of another simultaneously.