A sheet processing apparatus includes a sheet processing unit, a sheet feeder, and a unit cover. The sheet processing unit inserts an inner sheet into a two-ply sheet in which two sheets are overlapped and bonded together at one ends as a bonding portion. The sheet feeder is disposed above the sheet processing unit and is movable to open to expose the sheet processing unit. The sheet feeder feeds one of the two-ply sheet and the inner sheet. The unit cover is disposed above the sheet processing unit and opens to expose the sheet processing unit.

A sheet separation device includes a rotator, a nipping member to nip the two-ply sheet with the rotator, a first conveyor to convey the two-ply sheet in a first direction toward the rotator and a second direction reverse thereto, a winding member to wind the two-ply sheet around the rotator, a second conveyor to convey a sheet medium in the second direction, a separation claw to move in a width direction; a sheet guide to guide the separated two sheets to different passages; and control circuitry. The first conveyor conveys the two-ply sheet to the rotator with a bonded portion at an upstream end. The control circuitry inserts the separation claw into a space between the two sheets, adjusts a projection amount of the two-ply sheet from a nip of the first conveyor in the second direction, and inserts the sheet medium in two-ply sheet adjusted in the projection amount.

A sheet processing apparatus including a sheet feeder, a sheet processing device, a sheet ejection device, a purge unit, a multifeed sensor, and circuitry. The sheet feeder feeds a sheet toward a sheet conveyance passage. The sheet processing device performs a predetermined operation on the sheet. The sheet ejection device stacks the sheet when the predetermined operation has been performed. The purge unit stacks the sheet when the predetermined operation has not been performed. The multifeed sensor detects whether sheets are multifed and a number of multifed sheets. The circuitry counts a number of sheets, determines that the sheets stacked in the purge unit is full when a number of counted sheets reaches a predetermined number of sheets, and conveys the multifed sheets toward the purge unit and adds the number of counted sheets according to the number of multifed sheets, in response to detection of the multifed sheets.

A layer transfer device includes a housing main body having an opening, a cover movable between an open position in which the opening is open and a closed position in which the opening is closed, a heating member provided in the housing main body and configured to heat a multilayer film and a sheet, a pressure member provided on the cover and configured to nip the multilayer film and a sheet laid on the multilayer film between the heating member and the pressure member, and a shutter movable between a protecting position in which the heating member is covered with the shutter, and a retreated position in which the shutter is away from the protecting position. The shutter is in the protecting position when the cover is in the open position.

A sheet processing apparatus is configured to sandwich one or more sheet media in a two-ply sheet in which two sheets are overlaid and bonded together at a portion of the two-ply sheet. The sheet processing apparatus includes circuitry configured to control insertion processing to insert the one or more sheet media into the two-ply sheet based on a length of the two-ply sheet in a conveyance direction, a length of one of the one or more sheet media in the conveyance direction, and a number of the one or more sheet media.

A sheet processing device inserts a sheet-shaped medium into a two-ply sheet in which two sheets are overlaid and partially bonded. The sheet processing device includes control circuitry to execute a single insertion mode in which one sheet-shaped medium is inserted into the two-ply sheet and a multiple insertion mode in which a plurality of sheet-shaped media are inserted into the two-ply sheet along a conveyance direction. The control circuitry inserts the one sheet-shaped medium into the two-ply sheet in the single insertion mode and the plurality of sheet-shaped media into the two-ply sheet in the multiple insertion mode, with the two-ply sheet being stopped.

An image forming apparatus includes a sheet separation device, a first sheet feeder, a second sheet feeder, an image forming device, and circuitry. The sheet separation device is configured to separate a non-bonding portion of a two-ply sheet in which two sheets are overlapped and bonded together at a bonding portion of the two-ply sheet. The first sheet feeder is configured to feed the two-ply sheet. The second sheet feeder is configured to feed an inner sheet to be inserted between the two sheets. The image forming device is configured to form an image on a surface of the inner sheet. The circuitry is configured to cause the first sheet feeder to feed the two-ply sheet, perform a sheet separating operation on the two-ply sheet and cause the second sheet feeder to start feeding the inner sheet before completion of the sheet separating operation on the two-ply sheet.

A layer transfer device includes a supply reel, a take-up reel, a driving source, a releasable restraining device, a heating roller, a pressure roller, and a controller. The driving source drives the take-up reel. The releasable restraining device is capable of switching to a restraining state in which a multilayer film is put under restraint in being drawn out from the supply reel and to a release state in which the restraint is lifted. The controller is configured such that when the driving source is generating the mechanical power, the releasable restraining device is in the restraining state if an image area in which an image is formed on the sheet is not present in a layer transfer position between the heating roller and the pressure roller, and the releasable restraining device is in the release state if the image area is present in the layer transfer position.

A sheet processing device is configured to separate a non-bonding portion of a two-ply sheet in which two sheets are overlapped and bonded together at one end as a bonding portion of the two-ply sheet. The sheet processing device includes a first sheet feeder configured to feed the two-ply sheet, a second sheet feeder configured to feed an inner sheet to be inserted between the two sheets of the two-ply sheet in a state in which the non-bonding portion of the two-ply sheet is separated, and circuitry configured to cause the first sheet feeder to feed the two-ply sheet, perform a sheet separating operation on the two-ply sheet to separate the non-bonding portion of the two-ply sheet, and cause the second sheet feeder to start feeding the inner sheet before completion of the sheet separating operation on the two-ply sheet.

A sheet processing device sandwiches a sheet-shaped medium in a two-ply sheet in which two sheets are overlaid and partially bonded. The sheet processing device includes a separator, a conveyor, and a switching member. The separator separates the two sheets of the two-ply sheet. The conveyor is disposed downstream from the separator in a sheet conveyance direction and conveys the two-ply sheet. The switching member is disposed downstream from the conveyor in the sheet conveyance direction. The switching member switches a conveyance path of the two-ply sheet to convey the two-ply sheet to a fixing path on which fixing processing is performed on the two-ply sheet or a non-fixing path on which no fixing processing is performed on the two-ply sheet.