Sheet processing device and image formation apparatus provided with the same
A sheet processing device includes a plurality of first units and a second unit. The first units each include, as one unit, a pressing member that presses a folding loop, a frame that movably holds the pressing member in a sheet pressing direction, and an elastic member that is disposed between the frame and the pressing member to bias the pressing member in the sheet pressing direction. The second unit supports, as one unit, a plurality of rows of first units such that the first units of each row are arranged, as a pair, so as to be opposed to each other and that an interval between the pairs is reduced stepwise from a downstream side to an upstream side in a moving direction of the second unit.
1. A sheet processing device comprising:
a plurality of first units that press a folding loop of a folded sheet bundle; and
a second unit that is moved along the folding loop while supporting the first units, wherein
the first units each include, as one unit, a pressing member that presses the folding loop, a frame that movably holds the pressing member in a sheet pressing direction, and an elastic member that is disposed between the frame and the pressing member so as to bias the pressing member in the sheet pressing direction, and
the second unit supports, as one unit, a plurality of rows of the first units such that the first units of each row are arranged, as a pair, so as to be opposed to each other and that an interval between the pair is reduced stepwise from a downstream side to an upstream side in a moving direction of the second unit.
2. The sheet processing device according to claim 1 , wherein
the pressing member of the first unit has a roller that presses the folding loop while rotating.
3. The sheet processing device according to claim 2 , wherein
the first unit further slidably supports, along an inner wall of the frame, a roller bracket that supports the pressing roller and serves as a receiving member for the elastic member disposed between the roller bracket and the frame and has, on an outer wall of the frame, a support arm whose one end is fixed to the frame and the other end movably supports the roller bracket.
4. A sheet processing device comprising:
a plurality of pressing roller units that press a folding loop of a folded sheet bundle; and
a support unit that is moved along the folding loop while supporting the pressing roller units, wherein
the pressing roller units each include, as one unit, a rotatable pressing roller that presses the folding loop, a frame that movably holds a roller bracket that holds the pressing roller, and an elastic spring that is disposed between the frame and the roller bracket so as to bias the pressing roller in a sheet pressing direction, and
the support unit supports, as one unit, a plurality of rows of the pressing roller units such that each pressing roller unit is arranged in a pair opposed to each other and that an interval between the pair is reduced stepwise from a downstream side to an upstream side in a moving direction of the support unit and includes an adjustment member for adjusting a position of the pressing roller units.
5. A sheet processing device comprising:
a plurality of rows of pressing rollers that press a folding loop of a folded sheet bundle in a thickness direction; and
a support unit that moves the plurality of rows of pressing rollers along the folding loop with the pressing rollers of each row opposed to each other and supports the plurality of rows of pressing rollers such that an interval between the opposed pressing rollers is reduced stepwise from a downstream side to an upstream side in a moving direction of the support unit, wherein
the support unit includes, between the pressing rollers of adjacent rows in the moving direction, a guide member that guides the folding loop.
6. The sheet processing device according to claim 5 , wherein
there are a plurality of rows of the guide members,
the guide members are each constituted of a guide plate having a guide portion,
the guide portions are disposed as a pair between the pressing rollers of the adjacent rows so as to extend in the moving direction and to expose peripheral surfaces of the pressing rollers therebefore and thereafter, and
the folding loop is guided to a funnel cross-sectional-shaped space formed by the pressing rollers and the guide portions.
7. The sheet processing device according to claim 6 , wherein
the guide plate is positioned between the adjacent pressing rollers in the moving direction by the pressing roller disposed upstream or downstream thereof in the moving direction.
8. The sheet processing device according to claim 7 , wherein
the guide portions are disposed opposite to each other,
an interval between the guide portions is reduced from the downstream side to upstream side in the moving direction, and
the guide portions each have a guide slope inclined corresponding to the positions of the pressing rollers therebefore and thereafter.
9. The sheet processing device according to claim 8 , wherein
the pressing roller and the guide slope positioned upstream of the pressing roller in the moving direction of the support unit are disposed such that a tangent line forming an approximate right angle to a straight line passing through a center axis of the pressing roller in a direction substantially perpendicular to the moving direction of the support unit crosses the guide slope.
10. The sheet processing device according to claim 8 , wherein
the guide slope and the pressing roller positioned upstream of the guide slope in the moving direction of the support unit are disposed such that a guide upstream portion of the guide slope falls within a range of a peripheral surface of the pressing roller on the side of the guide portion that is surrounded by a straight line passing through a center axis of the pressing roller and extending along the moving direction of the support unit and a perpendicular line forming an approximate right angle to the straight line.
11. The sheet processing device according to claim 8 , wherein
the guide slope and the pressing roller positioned downstream of the guide slope are disposed such that a tangent line forming an approximate right angle, at a peripheral surface of the downstream side pressing roller, to a perpendicular line passing through a center axis of the downstream side pressing roller in a direction substantially perpendicular to the moving direction of the support unit crosses the guide slope, and
the guide slope and the pressing roller positioned upstream of the guide slope are disposed such that a guide upstream portion of the guide slope falls within a range of a peripheral surface of the upstream side pressing roller on a side of the guide slope that is surrounded by a straight line passing through a center axis of the upstream side pressing roller and extending along the moving direction of the support unit and a perpendicular line forming an approximate right angle to the straight line.
12. A sheet processing device comprising:
a plurality of rows of pressing members that press a folding loop of a folded sheet bundle in a thickness direction; and
a support unit that is moved along the folding loop with the pressing members of each row opposed to each other and supports the plurality of rows of the pressing members such that an interval between the opposed pressing members is reduced stepwise from a downstream side to an upstream side in a moving direction of the support unit; and
a guide plate disposed between the pressing members of adjacent rows in the moving direction of the support unit so as to guide the folding loop, wherein
the guide plate is positioned by the pressing member therebefore or thereafter.
13. The sheet processing device according to claim 12 , wherein
the guide plate is positioned and supported by the pressing member positioned upstream thereof in the moving direction of the support unit.
14. The sheet processing device according to claim 12 , wherein
the guide plate is positioned and supported by the pressing member positioned downstream thereof in the moving direction of the support unit.
15. The sheet processing device according to claim 13 , wherein
the pressing member includes a rotatable pressing roller that presses the folding loop and a pressing roller frame mounted to the support unit that supports the pressing roller, and
the guide plate includes a guide slope that guides the folding loop between the pressing rollers therebefore and thereafter and a mounting portion mounted to the upstream side pressing roller frame.
16. The sheet processing device according to claim 15 , the mounting portion of the guide plate to the pressing roller frame is a projection portion to be fitted to a cut portion or a concave portion formed in the upstream side pressing roller frame.
17. The sheet processing device according to claim 16 , wherein
the guide slope of the guide plate extends longer to the pressing rollers therebefore and thereafter in the moving direction than the mounting portion.
18. The sheet processing device according to claim 17 , wherein
there are a plurality of rows of the guide plates,
the guide plates each have the guide slope,
the guide slopes are disposed as a pair between the pressing rollers of the adjacent rows so as to extend in a direction crossing the moving direction and to expose peripheral surfaces of the pressing rollers therebefore and thereafter, and
the folding loop is guided to and pressed in a substantially funnel cross-sectional-shaped space formed by the pressing rollers and the guide slopes.
19. The sheet processing device according to claim 18 , wherein
the guide slope and the pressing roller positioned downstream of the guide slope are disposed such that a tangent line forming an approximate right angle, at a peripheral surface of the downstream side pressing roller, to a perpendicular line passing through a center axis of the downstream side pressing roller in a direction substantially perpendicular to the moving direction of the support unit crosses the guide slope, and
the guide slope and the pressing roller positioned upstream of the guide slope are disposed such that a guide upstream portion of the guide slope falls within a range of a peripheral surface of the upstream side pressing roller on a side of the guide slope that is surrounded by a straight line passing through a center axis of the upstream side pressing roller and extending along the moving direction of the support unit and a perpendicular line forming an approximate right angle to the straight line.
20. An image forming device comprising:
an image forming section that forms an image onto a sheet; and
a sheet processing device that applies predetermined sheet processing to the sheet from the image forming section, wherein
the sheet processing device is the sheet processing device as claimed in claim 1 .