According to an embodiment, a sheet processing apparatus includes a transport unit and a holding unit. The transport unit transports a first sheet to a first position. The transport unit transports a second sheet, which is transported after the first sheet, to a second position displaced to the upstream side of a sheet transport direction relative to the first position. The transport unit transports a third sheet, which is transported after the second sheet, to a third position displaced to the downstream side of the sheet transport direction relative to the second position. In the case where the second sheet is transported to the second position, the holding unit holds the first sheet at the first position. In the case where the third sheet is transported to the third position, the holding unit holds the second sheet at the second position.

Equipment for stacking sheets with a stack support, input rollers for feeding entering sheets and transport belts with lower branches arranged above the stack support. A compensation mechanism modifies the height of the stack support, while the transport belts are motorized to drag the entering sheets with the lower branches and deposit the sheets on the stack support or on stacked sheets. An arrest member is provided for the entering sheets, a pressure member for the stack to be stacked and a sensor device for a last sheet of the stack. The arrest member arrests the sheets in stacking while the pressure member is contiguous to the stop member and operates on the last sheet of the stack with a stabilizing function and in which the compensation mechanism is servoized to the sensor, for maintaining constant the height of the last sheet of the stack from a reference plane.

A medium ejection apparatus including: a placement mount on which media are placed; a medium-leading-edge position restriction part that moves between a restriction position at which the restriction part restricts a position of a leading edge portion of a medium ejected toward the placement mount with reference to an ejection direction of the medium and a retracted position retracted from the restriction position; and a medium position control unit that controls the medium-leading-edge position restriction part such that the medium-leading-edge position restriction part performs a leading-edge restriction operation of moving from the retracted position to the restriction position and moving from the restriction position to the retracted position when the medium-leading-edge position restriction part and an upper surface of a medium are not in contact with each other.

The sheet discharge apparatus sets a discharge speed at which a sheet is discharged by a discharge device to a first discharge speed when a bundle of sheets includes a first number of sheets and sets the discharge speed to a second discharge speed that is lower than the first discharge speed when the bundle of sheets includes a second number of sheets that is greater than the first number of sheets.

According to an embodiment, a sheet processing apparatus includes a transport unit and a holding unit. The transport unit transports a first sheet to a first position. The transport unit transports a second sheet, which is transported after the first sheet, to a second position displaced to the upstream side of a sheet transport direction relative to the first position. The transport unit transports a third sheet, which is transported after the second sheet, to a third position displaced to the downstream side of the sheet transport direction relative to the second position. In the case where the second sheet is transported to the second position, the holding unit holds the first sheet at the first position. In the case where the third sheet is transported to the third position, the holding unit holds the second sheet at the second position.

A post-processing apparatus for post-processing paper discharged from an image forming apparatus comprises: a paper discharging roller for conveying both first and second paper sequentially discharged from an image forming apparatus to an intermediate loading part; a main paddle part for conveying the first and second paper loaded on the intermediate loading part to a compiling region; a reverse roller for conveying, together with the main paddle part, the first and second paper to the compiling region; and a binding part for processing the first and second paper conveyed to the compiling region, the paper discharging roller allows the first paper to stand by on a standby path, and conveys the first and second paper to the intermediate loading part in a state in which the leading end of the first paper protrudes further than the leading end of the second paper.

A sheet stacking apparatus is provided. A conveyor unit performs stacking of sheets discharged from a printing apparatus and conveying of stacked sheets. A detection unit detects whether or not the printing apparatus is currently discharging a sheet. A control unit, so as to secure a stacking space for a sheet discharged from the printing apparatus on the conveyor unit, controls a feeding operation of the conveyor unit correspondingly to a period of time over which the detection unit detected that the printing apparatus is discharging a sheet.

A method of grouping sheet units, which belong together in sheet groups, a sheet stream comprising two superposed sheet units each by means of a grouping unit, a grouping unit for a sheet handling system, and a sheet handling system that allow a high processing speed and a high cycle efficiency of a sheet handling system are disclosed. A sheet unit can be held back in the grouping unit. Depending on whether the downstream subsequent sheet units transferred into the grouping unit belong to a sheet group, the held-back sheet unit can be released by itself and together with one or together with both downstream subsequent sheet units.

A sheet discharging apparatus includes a stacking portion, a first conveyance portion, a detection portion, a second conveyance portion, a third conveyance portion, and a control portion. The control portion is configured to execute a discharge operation by causing the sheet discharging apparatus to reverse a conveyance direction of a first sheet conveyed from the first conveyance portion to the second conveyance portion and deliver the first sheet to the third conveyance portion by using the second conveyance portion, convey the first sheet toward the second conveyance portion by the third conveyance portion, and discharge the first sheet and the second sheet to the stacking portion by using the second conveyance portion in a state where the first sheet and the second sheet are superimposed on each other.

A three side trimmer has a trimming unit 1, an accumulating unit 3, a discharge unit 2 and a conveying mechanism 4 conveying trimmed booklets BK to the accumulating unit. The accumulating unit has a shelf 5 movable in a vertical direction, and a drive roller conveyor 7 on the shelf. The accumulating unit, in a mode, delivers the trimmed booklets to the discharge unit at every accumulation of a predetermined number of the trimmed booklets and, in another mode, accumulates the trimmed booklets without delivering.