Abstract: A sheet separation device separates a non-bonding portion of a two-ply sheet in which two sheets are overlapped and bonded together at one end of the two-ply sheet. The sheet separation device includes a separator that includes a first separator and a second separator. The first separator is inserted into a gap between the two sheets of the two-ply sheet. The second separator is inserted between the two sheets at said another end of the two-ply sheet that is opposite to the one end of the two-ply sheet and moves in a width direction of the two-ply sheet after the first separator is inserted into the gap and relatively moves from the one end to said another end.

Abstract: A sheet separation device separates 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 sheet separation device includes a winding roller and a gripper. The winding roller rotates and winds the two-ply sheet to separate the two-ply sheet. The gripper is disposed in the winding roller and configured to grip a gripped portion of the two-ply sheet at one end of the two-ply sheet without abutting a tip of the gripped portion at the one end of the two-ply sheet on a member.

Abstract: An image forming system includes a sheet processing apparatus, a heat presser, an image forming apparatus, and control circuitry. The sheet processing apparatus separates a two-ply sheet in which two sheets are overlaid and bonded together at a portion of the two-ply sheet, and sandwiches a sheet medium between the sheets of the two-ply sheet. The heat presser heats and presses the two-ply sheet. The control circuitry performs a first mode to cause the sheet processing apparatus to sandwich the sheet medium, on which an image has been formed by the image forming apparatus, between the two sheets of the two-ply sheet and cause the heat presser to laminate the two-ply sheet, and a second mode to cause the heat presser to laminate a sheet set that includes the sheet medium sandwiched between the two sheets of the two-ply sheet by a user.

Abstract: A sheet processing apparatus laminates a partially joined two-ply sheet and a sheet medium inserted in the two-ply sheet. The sheet processing apparatus includes a heat presser, an information acquisition device, and control circuitry. The heat presser heats and presses the two-ply sheet and the sheet medium. The information acquisition device acquires information on the two-ply sheet and the sheet medium. The control circuitry sets a fixing temperature of the heat presser in accordance with the information of the two-ply sheet and the sheet medium acquired by the information acquisition device.

Abstract: A 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 one end as a bonding portion of the two-ply sheet. The sheet separation device includes a conveyance roller pair and circuitry. The conveyance roller pair is configured to convey the two-ply sheet while nipping the two-ply sheet, when separating the non-bonding portion of the two-ply sheet. The circuitry is configured to control sheet conveyance. The circuitry is configured to stop the conveyance roller pair, cause a leading end of the two-ply sheet conveyed toward the conveyance roller pair to contact a nip region of the conveyance roller pair while the conveyance roller pair is stopped, and start the conveyance roller pair to rotate to nip the two-ply sheet.

Abstract: An image forming system includes an image forming apparatus, a sheet processing device, and control circuitry. The image forming apparatus forms an image on a sheet. The sheet processing device performs post-processing on the sheet. The sheet processing device includes a first conveyance path through which the sheet is conveyed and subjected to the post-processing and a second conveyance path through which the sheet is conveyed without the post-processing. In response to an instruction of print jobs including both a print job of one or N copies subjected to the post-processing and a print job not subjected to the post-processing, the circuitry executes the job not subjected to the post-processing during execution of an M-th copy of the job subjected to the post-processing and causes the sheet to be conveyed through the second conveyance path, where N is two or greater and M satisfies 1?M<N.

Abstract: 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.

Abstract: A sheet separation device that conveys a two-ply sheet in a state where the one side joined is located on an upstream side or a downstream side of the two-ply sheet in a conveyance direction, separates the two-ply sheet into the two sheets, and inserts an inner sheet from a non-joined side opposite the joined side in the sheet conveyance direction so that the inner sheet is sandwiched between the two sheets overlaid with each other includes a conveying roller pair including a pair of rollers and circuitry. The conveying roller pair conveys the two-ply sheet and holds a joined portion of in the two-ply sheet at which the two sheets are joined, at a nip portion of the conveying roller pair when the inner sheet is inserted into the two-ply sheet. The circuitry contacts the inner sheet against the joined portion of the two-ply sheet to perform skew correction.

Abstract: A sheet processing device includes a sheet storage and a sheet displacer. The sheet storage includes a first storage portion that includes a first wall that is one side wall of the sheet storage and a second wall that is part of another side wall of the sheet storage and a second storage portion that includes a third wall continuous to the first wall and the second wall. The sheet displacer displaces a preceding sheet stored in the sheet storage and contacts an upper end of the preceding sheet to displace the preceding sheet such that the upper end of the preceding sheet moves toward the third wall. The second wall and the third wall are coupled via a bent portion that bends in a manner such that a storage space of the second storage portion is greater than a storage space of the first storage portion.

Abstract: A sheet feeder includes a sheet stacker, a sheet feed roller, a separation roller pair, and a lifter. Sheets are conveyed and stacked on the sheet stacker. The sheet feed roller feeds the sheets. The separation roller pair separates the sheets fed by the sheet feed roller one by one. The lifter lifts and lowers the sheet stacker depending on a stack amount of the sheets. The sheet stacker includes a first stacking face, a second stacking face, and a bent portion integrally connecting the stacking faces such that the stacking faces form a specified angle. The sheet stacker stacks the sheets such that a center of gravity of the sheets is positioned above the first stacking face and integrally displaces the stacking faces when the lifter operates.

Abstract: A sheet processing apparatus including a sheet feeder, a sheet processing device, a sheet ejection device, a purge unit, a multifeed sensor, a sheet sensor, and circuitry. The circuitry stops an operation of the sheet processing apparatus when the multifeed sensor has not detected multifeed of the sheet and the sheet sensor does not detect a trailing end of the sheet after a first set time from detection of a leading end of the sheet, stop the operation when the multifeed sensor has detected the multifeed and the sheet sensor does not detect the trailing end of the sheet after a second set time from the detection, and conveys the sheet toward the purge unit without stopping the operation when the multifeed sensor has detected the multifeed and the sheet sensor detects the trailing end of the sheet before the second set time elapses from the detection.

Abstract: 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.

Abstract: An image forming system includes an image forming apparatus and a sheet laminator. The image forming apparatus forms an image on a sheet being conveyed as an inner sheet. The sheet laminator performs a sheet laminating operation on a two-ply sheet in which the sheet conveyed from the image forming apparatus is inserted between two sheets of the two-ply sheet. The sheet laminator includes a heater and circuitry. The heater heats the two-ply sheet during the sheet laminating operation. The circuitry is to execute a control mode when a specific abnormal event occurs among a plurality of abnormal events that occurs in the image forming apparatus, where the control mode maintains heating by the heater of the sheet laminator for a predetermined time and interrupt the heating by the heater when an abnormal event other than the specific abnormal event occurs.

Abstract: A sheet processing device includes a conveyor, a rotator, a separator, and control circuitry. The conveyor conveys a sheet-shaped medium into a two-ply sheet in which two sheets are overlaid and partially bonded, and includes a drive roller and a driven roller. The rotator winds the two-ply sheet. The separator separates the two sheets of the two-ply sheet. The control circuitry causes the conveyor to convey the two-ply sheet in a winding direction to wind the two-ply sheet around the rotator to generate a space between the two sheets, and causes the separator to insert into the space between the two sheets to separate the two sheets. The drive roller and the rotator are disposed on a same side with respect to a sheet conveyance passage of the two-ply sheet, and the driven roller and the rotator are disposed on opposite sides with respect to the sheet conveyance passage.

Abstract: A laminating device inserts a sheet-shaped medium into a two-ply sheet in which two sheets are overlaid and partially bonded, and includes a loader, a fixing device, and control circuitry. The loader loads the sheet-shaped medium or a cleaning sheet. The fixing device laminates the two-ply sheet in which the sheet-shaped medium is sandwiched between the two sheets of the two-ply sheet. The control circuitry performs a cleaning mode of conveying a plurality of cleaning sheets from the loader to clean the fixing device. The cleaning mode is to convey a subsequent cleaning sheet of the plurality of cleaning sheets at a position different from a position of a preceding cleaning sheet of the plurality of cleaning sheets in a direction orthogonal to a conveyance direction of the plurality of cleaning sheets.

Abstract: 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.

Abstract: A sheet separation device separates 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 sheet separation device includes a winding roller, a conveyance roller pair, and a separation claw. The winding roller rotates and winds the two-ply sheet. The conveyance roller pair conveys the two-ply sheet toward the winding roller. The separation claw is inserted into a gap between the two sheets at a position between the winding roller and the conveyance roller pair. The separation claw is disposed in a space that is bounded by an imaginary plane and includes the winding roller. The imaginary plane passes through a nip of the conveyance roller pair and a winding start position at which the two-ply sheet starts to be wound around the winding roller.

Abstract: A sheet processing device separates a two-ply sheet in which two sheets are overlapped and partially bonded and sandwich a sheet medium between the two sheets. The sheet processing device includes a relay conveyance path, a sheet loader, and control circuitry. The sheet medium is fed from an image forming apparatus connected upstream of the sheet processing device through the relay conveyance path. The sheet loader loads at least one of the two-ply sheet and the sheet medium. The control circuitry performs a mixing mode to feed the two-ply sheet or the sheet medium from the sheet loader.

Abstract: A sheet separation device separates a non-bonding portion of a two-ply sheet in which two sheets are overlapped and bonded together at one end of the two-ply sheet. The sheet separation device includes a separator that includes a first separator and a second separator. The first separator is inserted into a gap between the two sheets of the two-ply sheet. The second separator is inserted between the two sheets at said another end of the two-ply sheet that is opposite to the one end of the two-ply sheet and moves in a width direction of the two-ply sheet after the first separator is inserted into the gap and relatively moves from the one end to said another end.

Abstract: A sheet separation device separates 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 sheet separation device includes a winding roller and a gripper. The winding roller rotates and winds the two-ply sheet to separate the two-ply sheet. The gripper is disposed in the winding roller and configured to grip a gripped portion of the two-ply sheet at one end of the two-ply sheet without abutting a tip of the gripped portion at the one end of the two-ply sheet on a member.