Sheet separation device, laminator, image forming apparatus, and image forming system
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.
1. A sheet separation device configured to separate a two-ply sheet in which two sheets are bonded together at a portion of the two-ply sheet, the sheet separation device comprising:
a rotator;
a nipping member disposed opposite the rotator and configured to nip the two-ply sheet with the rotator;
a conveyor configured to convey the two-ply sheet between the rotator and the nipping member with a bonded portion of the two-ply sheet being an upstream end or a downstream end of the two-ply sheet in a conveyance direction of the two-ply sheet;
a winding member disposed adjacent to the rotator and configured to wind the two-ply sheet around the rotator; and
control circuitry configured to rotate the rotator at a first speed faster than a second speed at which the two-ply sheet moves to the rotator via the conveyor in winding the two-ply sheet around the rotator, to create a difference in winding circumferential length between the two sheets and separate the two sheets.
2. The sheet separation device according to claim 1 ,
wherein the conveyor includes a pair of rotators configured to nip and convey the two-ply sheet, and
wherein a nipping force to nip the two-ply sheet between the rotator and the nipping member is greater than a nipping force to nip the two-ply sheet between the pair of rotators.
3. The sheet separation device according to claim 1 ,
wherein the control circuitry is configured to rotate the rotator in a state where the conveyor is not driven in winding the two-ply sheet around the rotator.
4. The sheet separation device according to claim 1 ,
wherein the nipping member is a first nipping member, and the winding member includes at least one second nipping member configured to nip the two-ply sheet with the rotator, and
wherein the at least one second nipping member is disposed around a circumference of the rotator and downstream from the first nipping member in a winding direction in which the rotator rotates to wind the two-ply sheet.
5. The sheet separation device according to claim 4 ,
wherein a nipping force to nip the two-ply sheet between the rotator and the at least one second nipping member is greater than a nipping force to nip the two-ply sheet between the rotator and the first nipping member.
6. The sheet separation device according to claim 4 ,
wherein the winding member includes a plurality of second nipping members around the circumference of the rotator, and
wherein a nipping force to nip the two-ply sheet between the rotator and each of the plurality of second nipping members increases in the winding direction in which the rotator rotates to wind the two-ply sheet.
7. The sheet separation device according to claim 4 ,
wherein the winding member includes a guide member at a distance from an outer circumferential surface of the rotator in a direction orthogonal to a rotation axis of the rotator, and
wherein the guide member is configured to guide the two-ply sheet along the outer circumferential surface of the rotator.
8. The sheet separation device according to claim 1 ,
wherein the conveyor is configured to convey the two-ply sheet in both a direction toward the rotator and a reverse direction retracting from the rotator.
9. The sheet separation device according to claim 8 ,
wherein, in winding the two-ply sheet around the rotator, the rotator winds the two-ply sheet with the bonded portion of the two-ply sheet being the upstream end in the conveyance direction in which the conveyor conveys the two-ply sheet toward the rotator.
10. The sheet separation device according to claim 9 , further comprising a separation claw disposed between the rotator and the conveyor in the conveyance direction and configured to move in a width direction of the two-ply sheet,
wherein the control circuitry is configured to:
insert, in the width direction, the separation claw into a space between the two sheets of the two-ply sheet; and
cause the conveyor to convey the two-ply sheet in the reverse direction retracting from the rotator with the separation claw inserted in the space, to separate the two sheets of the two-ply sheet.
11. The sheet separation device according to claim 10 , further comprising a sheet guide configured to guide the separated two sheets of the two-ply sheet to different passages,
wherein the conveyor is configured to convey the separated two sheets to the sheet guide, to open the two-ply sheet.
12. The sheet separation device according to claim 11 , further comprising:
a first stacking tray configured to store the two-ply sheet;
a first feeder configured to feed the two-ply sheet from the first stacking tray to the conveyor;
a second stacking tray configured to store a sheet medium to be inserted into the two-ply sheet; and
a second feeder configured to feed, from the second stacking tray, the sheet medium into the two-ply sheet.
13. A laminator comprising:
the sheet separation device according to claim 1 ; and
a heat and pressure member configured to heat and press together the two sheets of the two-ply sheet.
14. An image forming apparatus comprising:
a two-ply sheet tray configured to store the two-ply sheet;
a two-ply sheet feeder configured to feed the two-ply sheet from the two-ply sheet tray;
an image forming device configured to form an image on the two-ply sheet; and
the sheet separation device according to claim 1 , to separate the two sheets of the two-ply sheet.
15. The image forming apparatus according to claim 14 , further comprising a heat and pressure member configured to heat and press the two-ply sheet,
wherein the sheet separation device and the heat and pressure member comprise a laminator.
16. The image forming apparatus according to claim 14 , further comprising:
a medium tray configured to store a sheet medium;
a medium feeder configured to feed the sheet medium from the medium tray;
an image forming device configured to form an image on the sheet medium; and
an inserter configured to insert the sheet medium on which the image is formed into the two-ply sheet.
17. An image forming apparatus comprising:
a medium tray configured to store a sheet medium;
a medium feeder configured to feed the sheet medium from the medium tray;
an image forming device configured to form an image on the sheet medium;
the sheet separation device according to claim 1 , to separate the two sheets of the two-ply sheet; and
an inserter configured to insert the sheet medium on which the image is formed into the two-ply sheet.
18. The image forming apparatus according to claim 17 , further comprising a heat and pressure member configured to heat and press the two-ply sheet,
wherein the sheet separation device and the heat and pressure member comprise a laminator.
19. An image forming system comprising:
an image forming apparatus; and
the sheet separation device according to claim 1 , removably coupled to the image forming apparatus.
20. The image forming system according to claim 19 , further comprising a heat and pressure member configured to heat and press the two-ply sheet,
wherein the sheet separation device and the heat and pressure member comprise a laminator.