Patent ID: 8042796
Filing Date: 2011-10-25
Classification: B65H

Abstract:
1. A sheet finishing apparatus comprising: a conveyance mechanism to convey a sheet supplied from an image forming apparatus in a conveyance direction; a puncher having a plurality of punching blades and a corresponding plurality of punching blade receiving holes to bore punch holes in the sheet conveyed by the conveyance mechanism; a moving mechanism to locate the puncher at a penetrate position where the punch holes are bored in the sheet and a standby position where the puncher is retracted from the penetrate position in a direction perpendicular to the conveyance direction; a first detection section which is disposed upstream of the puncher in the conveyance direction and detects a leading edge of the sheet; a second detection section which is disposed upstream of the puncher in the conveyance direction and detects a lateral edge of the sheet while the puncher is moved from the standby position to the penetrate position; and a control section which controls the moving mechanism based on a detection timing of the first detection section and according to a size of the sheet and a movement speed of the sheet, and prevents a front corner of the sheet from coinciding with one of the punching blade receiving holes, wherein the control section controls a movement start timing of the puncher to the standby position according to positions of the punching blade receiving holes and the number of the punching blade receiving holes.