A stacking device which is detachably attached to an apparatus body of an image forming apparatus having an abutting member that abuts on a recording material and on which a recording material is stacked includes: a first supporting unit that supports the recording material from a lower side of the recording material; and a second supporting unit that supports an end of the recording material in an attachment/detachment direction of the stacking device. The second supporting unit includes a corresponding region, and a position of the corresponding region agrees with a position of the abutting member abut with the recording material in a width direction which is orthogonal to the attachment/detachment direction. At least a height of the corresponding region in a direction orthogonal to the attachment/detachment direction and the width direction is lower than a height of the abutting member.

In some examples, a sheet processing machine includes an at least one pile formation device. The at least one pile formation device is arranged so as to be displaceable at least in an inward-moving direction. The at least one pile formation device includes a plane. The at least one pile formation device is displaceable at least in a vertical direction relative to at least one lower multiple-up separating tool by means of a lifting device. In a temporary storage position, at least the plane is arranged in a vertical direction beneath a plane of the at least one lower multiple-up separating tool.

In some examples, a sheet processing machine includes an at least one pile formation device. The at least one pile formation device is arranged so as to be displaceable at least in an inward-moving direction. The at least one pile formation device includes a plane. The at least one pile formation device is displaceable at least in a vertical direction relative to at least one lower multiple-up separating tool by means of a lifting device. In a temporary storage position, at least the plane is arranged in a vertical direction beneath a plane of the at least one lower multiple-up separating tool.

A sheet handling apparatus configured to feed sheets from outside into the sheet handling apparatus, transport the fed sheets in a storage area which is outside of a storage bag in the sheet handling apparatus and store the transported sheets in the storage bag includes: a holder configured to be capable of detachably holding the storage bag; a pushing member configured to push a plurality of sheets transported in the storage area into the storage bag through the opening of the storage bag; and a pressing member configured to press the sheets stored in the storage bag held by the holder.

A sheet handling apparatus configured to feed sheets from outside into the sheet handling apparatus, transport the fed sheets in a storage area which is outside of a storage bag in the sheet handling apparatus and store the transported sheets in the storage bag includes: a holder configured to be capable of detachably holding the storage bag; a pushing member configured to push a plurality of sheets transported in the storage area into the storage bag through the opening of the storage bag; and a pressing member configured to press the sheets stored in the storage bag held by the holder.

A control device executes: either a first conveyance change control or a second conveyance change control; and a retraction control when an operation device receives an interruption operation during execution of a specified number stack control. In the first conveyance change control, a sheet conveyance device of a target unit is changed to a relay conveyance state, and the sheet conveyance device of another coupled unit that is present downstream of the target unit in a main conveyance direction is changed to a stack conveyance state. In the second conveyance change control, the sheet conveyance device of another coupled unit that is present upstream in the main conveyance direction is changed to the stack conveyance state. In the retraction control, a lift mechanism of the target unit is caused to execute a mount operation by which a stack tray is moved down to a mount position on a carriage portion.

Each of the sheets is conveyed by a horizontal conveyance unit in a state of being overlapped with a next sheet from above. Each of the sheets is conveyed out of the horizontal conveyance unit in a state of being folded along a fold line with the fold line oriented upward, the fold line extending in a conveyance direction of the horizontal conveyance unit. An oblique conveyance unit receives the sheet from the horizontal conveyance unit and successively conveys the sheets in an oblique downward direction. A sensor is arranged to detect passage of the sheets at a position where steps pass. Each of the steps is formed by two sheets adjacent to each other diverted to the oblique downward direction by the oblique conveyance unit.

An example finisher includes a first portion extending in a vertical direction and including a height adjustment unit, a second portion extending from the first portion in a lateral direction and including a finishing unit to perform a finishing process, and a stacker to receive paper discharged from the finishing unit, the stacker extending in an opposite direction to the second portion in the lateral direction. The height adjustment unit is to adjust a height of the second portion from an installation surface and includes a base plate including a horizontal slot, a guide plate including an inclined slot, and a slide lever coupling the horizontal slot and the inclined slot.

An example finisher includes a first portion extending in a vertical direction and including a height adjustment unit, a second portion extending from the first portion in a lateral direction and including a finishing unit to perform a finishing process, and a stacker to receive paper discharged from the finishing unit, the stacker extending in an opposite direction to the second portion in the lateral direction. The height adjustment unit is to adjust a height of the second portion from an installation surface and includes a base plate including a horizontal slot, a guide plate including an inclined slot, and a slide lever coupling the horizontal slot and the inclined slot.

A sheet stacking device includes a sheet stacker, an image capturing device, and circuitry. The sheet stacker stacks a sheet. The image capturing device captures an image of a whole face of the sheet stacked in the sheet stacker. The circuitry detects a size of the sheet stacked in the sheet stacker, whether the sheet stacked in the sheet stacker is a last sheet, or whether an image is formed on an image forming face of the sheet, based on image data of the image captured by the image capturing device.