Patent ID: 7431291

Claim:
A delivery processing apparatus comprising: an alignment stage, which stacks sheets to be aligned; a conveying rotary member, which conveys a sheet to the alignment stage; an alignment member movable to a direction intersecting with a sheet conveyance direction in order to align the sheets stacked on the alignment stage; a stacking tray, which stacks a bundle of aligned sheets; a pair of delivery rotary members movable between a conveying position for delivering the bundle of the sheets to the stacking tray and a separating position, wherein the pair of delivery rotary members are separated from each other; and a detecting unit including a detection member selectively moving between a detection position and a non-detection position, which detects a stacking amount of the sheets stacked on the stacking tray, wherein the detection unit starts a detection of the stacking amount of the sheets stacked on the stacking tray after the pair of delivery rotary members is moved to the conveying position and the alignment member is moved to an escaping position where the delivery of the sheets is not prevented by the alignment member.