Abstract: A sheet stacking apparatus includes an ejector, a stacker, a wall, and an upper surface detector. The ejector ejects a sheet, and the stacker stacks the sheet ejected from the ejector. The wall contacts a trailing end of the sheet ejected from the ejector in an ejection direction to align the sheet. The upper surface detector detects an upper surface on a trailing end side of the sheet stacked on the stacker in the ejection direction. When the sheet moves toward the wall, the upper surface detector moves from a home position in which the upper surface detector detects the upper surface of the sheet to a retracted position in which the upper surface detector does not contact the sheet moving toward the wall.

Abstract: A binding device includes a stacking device configured to receive sheets, a sheet alignment member configured to align the sheets on the stacking device, a binder configured to bind the sheets on the stacking device, a binder moving device configured to move the binder, and a retreat device configured to retreat the sheet alignment member from a range of movement of the binder. The retreat device retreats the sheet alignment member in response to a pressing force acting on the sheet alignment member in a direction of movement of the binder.

Abstract: A fold-enforcing assembly includes a fold-enforcing device, a moving device to move the fold-enforcing device in a direction of a fold of a sheet bundle, and control circuitry. The fold-enforcing device includes a pressing member pair to nip and press the fold of the sheet bundle in a direction of thickness, a pressing mechanism to pressurize and depressurize the pressing member pair, and a driver to drive the pressing mechanism. Controlled by the control circuitry, the moving device moves the fold-enforcing device in accordance with a size of the sheet bundle in the direction of the fold; pressing mechanism pressurizes the pressing member pair to press a first end portion of the sheet bundle in the direction of the fold; the moving device moves the fold-enforcing device to a second end portion of the sheet bundle; and pressing mechanism depressurizes the pressing member pair in the second end portion.

Abstract: A binding device includes a stacking device configured to receive sheets, a sheet alignment member configured to align the sheets on the stacking device, a binder configured to bind the sheets on the stacking device, a binder moving device configured to move the binder, and a retreat device configured to retreat the sheet alignment member from a range of movement of the binder. The retreat device retreats the sheet alignment member in response to a pressing force acting on the sheet alignment member in a direction of movement of the binder.

Abstract: A fold-enforcing assembly includes a fold-enforcing device, a moving device to move the fold-enforcing device in a direction of a fold of a sheet bundle, and control circuitry. The fold-enforcing device includes a pressing member pair to nip and press the fold of the sheet bundle in a direction of thickness, a pressing mechanism to pressurize and depressurize the pressing member pair, and a driver to drive the pressing mechanism. Controlled by the control circuitry, the moving device moves the fold-enforcing device in accordance with a size of the sheet bundle in the direction of the fold; pressing mechanism pressurizes the pressing member pair to press a first end portion of the sheet bundle in the direction of the fold; the moving device moves the fold-enforcing device to a second end portion of the sheet bundle; and pressing mechanism depressurizes the pressing member pair in the second end portion.

Abstract: A sheet stacking apparatus includes an ejector, a stacker, a wall, and an upper surface detector. The ejector ejects a sheet, and the stacker stacks the sheet ejected from the ejector. The wall contacts a trailing end of the sheet ejected from the ejector in an ejection direction to align the sheet. The upper surface detector detects an upper surface on a trailing end side of the sheet stacked on the stacker in the ejection direction. When the sheet moves toward the wall, the upper surface detector moves from a home position in which the upper surface detector detects the upper surface of the sheet to a retracted position in which the upper surface detector does not contact the sheet moving toward the wall.

Abstract: A sheet medium adjustment apparatus, e.g., in an image forming system, includes: an ejector to eject a conveyed sheet; a stacking device to stack each sheet ejected from the sheet ejector into a stack on a tray; a moving device to shift the stacking device in a movement direction perpendicular to a sheet-ejecting direction; a sheet aligning member to align ends of the sheets in the stack that are parallel to the sheet-ejecting direction; a stepping motor to move the sheet aligning member; and an evacuation device to evacuate the aligning member by an amount representing an evacuation displacement in the movement direction at a timing of aligning the sheet, the evacuation displacement being determined adaptively according to at least one of an attribute of a given sheet in the stack, an attribute of the stack as a whole and an attribute of the tray.

Abstract: A sheet medium adjustment apparatus, e.g., in an image forming system, includes: an ejector to eject a conveyed sheet; a stacking device to stack each sheet ejected from the sheet ejector into a stack on a tray; a moving device to shift the stacking device in a movement direction perpendicular to a sheet-ejecting direction; a sheet aligning member to align ends of the sheets in the stack that are parallel to the sheet-ejecting direction; a stepping motor to move the sheet aligning member; and an evacuation device to evacuate the aligning member by an amount representing an evacuation displacement in the movement direction at a timing of aligning the sheet, the evacuation displacement being determined adaptively according to at least one of an attribute of a given sheet in the stack, an attribute of the stack as a whole and an attribute of the tray.