| 摘要 |
PROBLEM TO BE SOLVED: To accurately perform punching even if a connecting distance between an image forming apparatus and an aftertreatment device for forming a punch hole is long.SOLUTION: A puncher moves a punch unit 710 to a waiting position according to sizes of paper sheets P to be punched based on paper size information transmitted from an image forming apparatus (S100, S110). When a first sheet is conveyed from the image forming apparatus, the punch unit is moved from a waiting position in the sheet width direction, whereby a side edge of the sheet is detected (S120). When the side end of the sheet is detected, the punch unit is moved from the paper detecting position to a punch position (S120), and a punch hole is formed in the first sheet (S130). Since a second sheet is conveyed to the puncher slightly late by delay control, the punching operation can be performed in the first sheet at a time when the vibration of the punch unit is stopped. Accordingly, the displacement of the punch hole of the first sheet caused by the effect of the vibration of the punch unit can be prevented. |
