Abstract: A sheet separation device separates a two-ply sheet in which two sheets are bonded together at a portion. The sheet separation device includes a rotator, a nipping member opposite the rotator, to nip the two-ply sheet with the rotator, a conveyor to convey the two-ply sheet between the rotator and the nipping member, a winding member adjacent to the rotator, to wind the two-ply sheet around the rotator, and control circuitry. In winding the two-ply sheet, the control circuitry rotates the rotator at a first speed faster than a second speed at which the two-ply sheet moves to the rotator via the conveyor, and creates a difference in winding circumferential length between the two sheets, thereby separating the two sheets. The conveyor conveys the two-ply sheet with a bonded portion of the two-ply sheet being an upstream end or a downstream end in a conveyance direction of the two-ply sheet.

Abstract: A sheet folding system includes a plurality of sheet folding apparatuses configured to receive and perform a folding process on a sheet and circuitry configured to distribute sheets to the plurality of sheet folding apparatuses. Each of the plurality of sheet folding apparatuses includes a folding device configured to fold the sheet, a first conveyance passage configured to convey the sheet downstream in a sheet conveyance direction without passing through the folding device, a second conveyance passage configured to convey the sheet to the folding device, a third conveyance passage configured to convey the sheet from the folding device downstream in the sheet conveyance direction, and a junction between the first conveyance passage and the third conveyance passage. The circuitry controls sheet conveyance to prevent an interference, at the junction, between the sheet conveyed from the first conveyance passage and the sheet conveyed from the third conveyance passage.

Abstract: A sheet processing apparatus includes a first conveyer to convey a sheet, a first folding device to fold the sheet and put a crease in the sheet, a second conveyer to convey the sheet folded by the first folding device, a second folding device to fold the sheet and put a crease in the sheet, and a guide. The first conveyer and the second conveyer are rotatable in reverse. The guide guides the sheet conveyed downstream from the first conveyer and the sheet conveyed downstream from the second conveyer.

Abstract: A folding apparatus includes a folding device to fold a sheet bundle, an additional folding device, a conveyer, and control circuitry. The additional folding device includes a pressure roller disposed downstream from the folding device in a sheet conveyance direction and configured to press the sheet bundle after the folding device folds the sheet bundle and a sheet support member disposed opposite the pressure roller via the sheet bundle. The conveyer conveys the sheet bundle to a position at which the additional folding device presses the sheet bundle and hold the sheet bundle at the position. The control circuitry causes the additional folding device to perform additional folding processing on a first position of the sheet bundle, the conveyer to move the sheet bundle to a second position different from the first position, and the additional folding device to perform the additional folding processing at the second position again.

Abstract: A sheet processing apparatus includes a rotatable pressing member, a guide, and a contact member. The rotatable pressing member includes a pressing portion that is disposed in a predetermined range in a rotation direction of the pressing member to press a folded portion of a sheet. The guide is disposed opposite the pressing member. The contact member contacts the guide and is rotatably disposed at at least one end of the pressing member in an axial direction of the pressing member.

Abstract: A sheet processing apparatus includes: a conveying unit configured to convey a sheet along a sheet conveyance path; a conveyance-path supporting unit configured to support both ends of the sheet conveyance path with respect to a direction perpendicular to a sheet conveying direction; a first stitching unit configured to stitch the sheets conveyed; a second stitching unit configured to stitch the sheets conveyed; a first moving unit configured to move the first stitching unit in a direction perpendicular to the sheet conveying direction; and a second moving unit configured to move the second stitching unit in a direction perpendicular to the sheet conveying direction, wherein any one of the first stitching unit and the second stitching unit is movable to outside of the conveyance-path supporting unit.

Abstract: A sheet processing device is for binding sheets together. The sheet processing device includes binding units differing from each other in maximum sheet count, the maximum sheet count being a maximum number of sheets that can be bound at a time; a sheet tray configured to hold sheets until all to-be-bound sheets are placed therein, the number of the to-be-bound sheets being a largest one of the maximum sheet counts of the binding units or smaller; and a stacked-sheet-count limiting unit situated in a thickness direction of the sheets held in the sheet tray. The stacked-sheet-count limiting unit is configured to limit the number of sheets held in the sheet tray by varying a distance from a sheet support surface of the sheet tray on which the sheets are placed, depending on one of the binding units by which the sheets held in the sheet tray are to be bound.

Abstract: A sheet processing device is for binding sheets together. The sheet processing device includes binding units differing from each other in maximum sheet count, the maximum sheet count being a maximum number of sheets that can be bound at a time; a sheet tray configured to hold sheets until all to-be-bound sheets are placed therein, the number of the to-be-bound sheets being a largest one of the maximum sheet counts of the binding units or smaller; and a stacked-sheet-count limiting unit situated in a thickness direction of the sheets held in the sheet tray. The stacked-sheet-count limiting unit is configured to limit the number of sheets held in the sheet tray by varying a distance from a sheet support surface of the sheet tray on which the sheets are placed, depending on one of the binding units by which the sheets held in the sheet tray are to be bound.

Abstract: A sheet processing apparatus includes a roller pair configured to convey a sheet, a sheet bundle conveyer configured to convey a sheet bundle to the roller pair, and circuitry configured to cause the sheet bundle conveyer to contact leading edges of sheets of the sheet bundle to the roller pair and cause the roller pair to rotate in reverse to align the leading edges of the sheets of the sheet bundle.

Abstract: A pair of binding teeth is configured to apply pressure to a sheet bundle to crimp-bind the sheet bundle. The pair of binding teeth includes a binding unit configured to have two or more binding areas which differ in tooth height and crimping portions thereof come in contact when the binding teeth are pressed against each other in the binding areas.

Abstract: A sheet binding unit includes a first sheet binder having first and second dentate uneven sheet binding elements to conduct a first sheet binding process by engaging each other by a prescribed meshing depth while sandwiching the sheet bundle therebetween to form a dentate unevenness on the sheet bundle at a first sheet binding portion of the sheet bundle, and a second sheet binder having third and fourth dentate uneven sheet binding elements to conduct a second sheet binding process by engaging each other by a greater meshing depth than that made by first and second dentate uneven sheet binding elements of the first sheet binder while sandwiching the sheet bundle therebetween to form a dentate unevenness on the sheet bundle at a second sheet binding portion different from the first sheet binding portion of the sheet bundle.

Abstract: A sheet processing apparatus includes a first conveyer to convey a sheet, a first folding device to fold the sheet and put a crease in the sheet, a second conveyer to convey the sheet folded by the first folding device, a second folding device to fold the sheet and put a crease in the sheet, and a guide. The first conveyer and the second conveyer are rotatable in reverse. The guide guides the sheet conveyed downstream from the first conveyer and the sheet conveyed downstream from the second conveyer.

Abstract: A sheet processing apparatus includes a rotatable pressing member, a guide, and a contact member. The rotatable pressing member includes a pressing portion that is disposed in a predetermined range in a rotation direction of the pressing member to press a folded portion of a sheet. The guide is disposed opposite the pressing member. The contact member contacts the guide and is rotatably disposed at at least one end of the pressing member in an axial direction of the pressing member.

Abstract: A sheet processing apparatus includes conveyers to convey a sheet. The conveyers include a registration conveyer which a plurality of sheets is to sequentially contact and is configured to bend a preceding sheet contacting the registration conveyer toward a direction in which the preceding sheet does not obstruct an entry of a following sheet to the registration conveyer when the conveyers overlay and convey the plurality of sheets after the plurality of sheets sequentially contacts the registration conveyer.

Abstract: A sheet processing apparatus includes a folding device to fold a sheet and a fold-enhancing device to press a folded portion of the sheet folded by the folding device to perform enhanced folding processing on the sheet whose trailing edge has exited the folding device.

Abstract: A sheet processing apparatus includes an entry portion, a sheet conveyance path extending from the entry portion, a skew correction roller pair that contacts a leading edge of a sheet conveyed in a predetermined direction from the entry portion to correct skew of the sheet, and a receiving path. The skew correction roller pair conveys the skew-corrected sheet in a direction opposite the predetermined direction. The receiving path branches from the sheet conveyance path from the entry portion to the skew correction roller pair to receive the sheet conveyed in the direction opposite the predetermined direction.

Abstract: A sheet processing apparatus includes a blade having a plurality of teeth aligned in a row, a mover to move in a direction in which the plurality of teeth is aligned and form a perforation in a sheet sandwiched by the blade and the mover, and a pressure device to press the mover toward the blade.

Abstract: A folding apparatus includes a folding device to fold a sheet bundle, an additional folding device, a conveyer, and control circuitry. The additional folding device includes a pressure roller disposed downstream from the folding device in a sheet conveyance direction and configured to press the sheet bundle after the folding device folds the sheet bundle and a sheet support member disposed opposite the pressure roller via the sheet bundle. The conveyer conveys the sheet bundle to a position at which the additional folding device presses the sheet bundle and hold the sheet bundle at the position. The control circuitry causes the additional folding device to perform additional folding processing on a first position of the sheet bundle, the conveyer to move the sheet bundle to a second position different from the first position, and the additional folding device to perform the additional folding processing at the second position again.

Abstract: A sheet processing device includes: a stacking unit configured to stack a plurality of sheets to obtain a sheet bundle; a stitched-sheet number acquiring unit configured to acquire a number of sheets in the sheet bundle, which is a target to be stitched; a permanent stitching unit configured to permanently stitch the sheet bundle; a temporary stitching unit configured to be capable of temporarily stitching a plurality of areas of the sheet bundle; a selecting unit configured to select any one of the permanent stitching unit and the temporary stitching unit to be used; and a stitching-process control unit configured to, when the temporary stitching unit is selected by the selecting unit, control the temporary stitching unit so as to change a number of areas that are stitched by the temporary stitching unit.

Abstract: A sheet processing apparatus includes a first binding unit configured to bind a sheet bundle; a second binding unit with greater number of bindable sheets than number of bindable sheets of the first binding unit; and a number-of-sheets determining unit configured to determine whether number of to-be-bound sheets exceeds the number of bindable sheets of the first binding unit. The first binding unit moves to a binding position, and if the number-of-sheets determining unit determines that the number of to-be-bound sheets exceeds the number of bindable sheets of the first binding unit, the first binding unit moves away from the binding position. When the number-of-sheets determining unit determines that the number of to-be-bound sheets exceeds the number of bindable sheets of the first binding unit, the second binding unit moves to the binding position.