Booklet processing apparatus operative to switch between delivery mode and accumulating mode

A booklet processing apparatus comprising:

• a discharge unit arranged downstream of a booklet processing unit which perform processing on one or more booklets to discharge the processed booklets;
• an accumulating unit arranged between the booklet processing unit and the discharge unit and operative to switch between a delivery mode in which the accumulating unit delivers a predetermined number of the processed booklets to the discharge unit and an accumulation mode in which the accumulating unit accumulates the processed booklets without delivering the processed booklets to the discharge unit, the accumulating unit including
• a shelf movable in a vertical direction, the processed booklets being placed on the shelf;
• an elevating mechanism moving the shelf up and down on the basis of a thickness of the processed booklets placed on the shelf;
• and
• a conveying mechanism conveying the processed booklets from the booklet processing unit to the accumulating unit, wherein
• during operation of the accumulating unit in the delivery mode,
• the accumulating unit includes a conveyor belt or a drive roller conveyor arranged on the shelf and adapted to supply the processed booklets placed on the shelf to an entrance of the discharge unit,
• the shelf of the accumulating unit is lowered from a height equal to the exit of the processing unit by a distance corresponding to a thickness of the processed booklets,
• the shelf is moved to a height equal to the entrance of the discharge unit and stopped in a manner such that the conveyor belt or the drive roller conveyor supplies the predetermined number of the processed booklets to the discharge unit when the predetermined number of the processed booklets are accumulated on the shelf,
• thereafter the shelf is moved to the height equal to the exit of the booklet processing unit so as to receive the next processed booklets, and
• during operation of the accumulating unit in the accumulation mode,
• the shelf of the accumulating unit is lowered from the height equal to the exit of the booklet processing unit by a distance corresponding to the thickness of the processed booklets until the number of the processed booklets accumulated on the shelf reaches the maximum number of the processed booklets that can be accommodated by the accumulating unit or a predetermined numerical value.