JP6013107B2 - Paper discharge device - Google Patents

Description

  The present invention relates to a paper discharge device that discharges printed paper.

  2. Description of the Related Art Conventionally, a paper discharge device that discharges paper printed by a printing device is known.

  Some paper discharge devices have side fences for regulating the positions of both ends of paper to be discharged in the paper width direction. Furthermore, a paper discharge device having a paper discharge base on which paper is stacked in a substantially U shape is known in order to improve the alignment by applying stiffness to the paper (see, for example, Patent Document 1). .

JP 2008-195459 A

  As described above, in a paper discharge device in which sheets are stacked in a substantially U shape, the curvature of the sheet at the top of the stacked sheets increases as the number of sheets stacked increases. As a result, the gap between the side fence and the paper is widened above the stacked paper. As a result, the sheet alignment may be deteriorated.

  The present invention has been made in view of the above, and an object of the present invention is to provide a paper discharge device that can suppress a decrease in paper alignment.

  In order to achieve the above object, a first feature of the paper discharge device according to the present invention is that the discharged paper is substantially U-shaped in which both sides in the paper width direction orthogonal to the paper discharge direction are curved upward from the center. A pair of side fences that regulate the positions of both ends in the paper width direction of the paper that is suspended above the paper discharge table and is discharged onto the paper discharge table. A lifting drive unit that raises and lowers the paper table, a side fence adjustment unit that adjusts the distance between the pair of side fences, and a top surface position of the paper stacked on the paper discharge table during the paper discharge operation. And a controller for lowering the discharge table by the lift driving unit, and the control unit adjusts the interval by the side fence adjusting unit according to an increase in the number of sheets stacked on the discharge table. Characterized by controlling to narrow A.

  A second feature of the paper discharge device according to the present invention is that the side fence adjusting unit adjusts the distance by moving the pair of side fences.

  A third feature of the paper discharge device according to the present invention is that the side fence adjusting unit adjusts the interval by rotating the side fences in the paper width direction.

  A fourth feature of the paper discharge device according to the present invention is that a pair of paper discharge wings that curve the paper discharged to the paper discharge tray into a substantially U shape, and a paper discharge wing that moves the pair of paper discharge wings. A paper wing drive unit, and the control unit is configured to reduce the distance between the pair of paper discharge wings by the paper discharge wing drive unit in conjunction with the operation of reducing the interval by the side fence adjusting unit. There is to move.

  A fifth feature of the paper discharge device according to the present invention is that the control unit maintains the upper surface position of the sheets stacked on the paper discharge table when performing the operation of narrowing the interval by the side fence adjusting unit. Therefore, the operation of narrowing the interval is started after the lowering of the discharge tray for starting.

  According to the first feature of the paper discharge device according to the present invention, the distance between the pair of side fences is reduced in accordance with an increase in the number of sheets stacked on the paper discharge table. As a result, the paper discharge device can prevent the gap between the side fence and the paper from becoming large even when the curvature of the paper is large at the top of the stacked paper on the paper discharge tray. As a result, it is possible to suppress a decrease in sheet alignment.

  According to the second feature of the paper discharge device according to the present invention, it is possible to prevent the gap between the side fence and the paper from increasing by moving the pair of side fences.

  According to the third feature of the paper discharge device according to the present invention, it is possible to prevent an increase in the gap between the side fence and the paper by rotating each side fence in the paper width direction.

  According to the fourth feature of the paper discharge device according to the present invention, the leading edge of the paper discharged to the paper discharge tray collides with the side fence by moving the pair of paper discharge wings so as to reduce the distance between them. Can be prevented, and paper discharge failure can be prevented.

  According to the fifth feature of the paper discharge device according to the present invention, the side fence is placed on the paper discharge table by starting the operation of reducing the distance between the pair of side fences after the paper discharge table starts to descend. Collision with the loaded paper can be avoided.

1 is an overall schematic diagram of a paper discharge device according to a first embodiment. FIG. 3 is a block diagram illustrating a configuration of a control system of the paper discharge device according to the first embodiment. It is the figure which looked at the paper discharge stand from the left-right direction. FIG. 6 is a plan view of a paper discharge wing. It is the figure which looked at the paper discharge wing from the right side. FIG. 10 is a diagram illustrating a result of measuring a change in an upper surface inclination angle and a change in a gap between a side fence whose position is fixed and a sheet according to an increase in the number of sheets stacked. It is a figure which shows the state which the clearance gap between the side fence and the paper became large. It is a flowchart for demonstrating the movement control of a side fence. It is a figure which shows the state which narrowed the space | interval of the side fence in 1st Embodiment. It is the whole paper discharge device schematic diagram concerning a 2nd embodiment. FIG. 6 is a block diagram illustrating a configuration of a control system of a paper discharge device according to a second embodiment. It is explanatory drawing of the side fence in 2nd Embodiment. It is a figure which shows the state which narrowed the space | interval of the side fence in 2nd Embodiment.

  Embodiments of the present invention will be described below with reference to the drawings. Throughout the drawings, the same or equivalent parts and components are denoted by the same or equivalent reference numerals. However, it should be noted that the drawings are schematic and different from the actual ones. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

  Further, the embodiment described below exemplifies an apparatus or the like for embodying the technical idea of the present invention, and the technical idea of the present invention is to arrange the components and the like as follows. It is not something specific. The technical idea of the present invention can be variously modified within the scope of the claims.

(First embodiment)
FIG. 1 is an overall schematic diagram of a paper discharge device according to the first embodiment, and FIG. 2 is a block diagram illustrating a configuration of a control system of the paper discharge device according to the first embodiment. In the following description, the paper surface direction of FIG. Moreover, as shown in FIG. 1, when viewed from the user, the vertical and horizontal directions are the vertical and horizontal directions.

  As shown in FIGS. 1 and 2, the paper discharge device 1 includes a transport unit 2, a paper discharge table 3, an elevator unit 4, a lift motor 5, an upper surface detection sensor 6, and a pair of paper discharge wings 7 </ b> A, 7B, a paper discharge wing movement motor 8, a pair of side fences 9A and 9B, a side fence movement motor 10, an end fence 11, an end fence movement motor 12, a ceiling portion 13, and a control portion 14. .

  The transport unit 2 transports the printed paper P sent from a printing device (not shown) connected to the left side of the paper discharge device 1 and discharges it to the paper discharge tray 3. The transport unit 2 discharges the paper P sent out from the printing apparatus while keeping the vertical direction as it is, or discharges the paper P by turning it upside down.

  Here, a path indicated by a thick line in FIG. 1 is a transport path along which the paper P is transported in the transport unit 2. Among the transport routes, a route indicated by a solid line is a paper discharge route RD, and a route indicated by a broken line is a reverse route RR. In the following description, upstream and downstream mean upstream and downstream in the transport path.

  The transport unit 2 includes an entrance roller 21, a plurality of pairs of intermediate rollers 22, a plurality of pairs of paper discharge rollers 23, a first switching unit 24, a plurality of pairs of forward rollers 25, a reverse roller 26, and a plurality of pairs of pairs. A return roller 27, a second switching unit 28, and a paper discharge sensor 29 are provided.

  The entrance roller 21 takes the printed paper P from the printing device into the paper discharge device 1. The entrance roller 21 is disposed at the most upstream part of the paper discharge path RD. The upstream end of the paper discharge path RD is connected to the downstream end of the transport path of the printing apparatus. The entrance roller 21 is driven by a motor (not shown).

  The plurality of pairs of intermediate rollers 22 convey the paper P taken from the printing apparatus by the entrance roller 21 to the paper discharge roller 23. The plurality of pairs of intermediate rollers 22 are arranged at a predetermined interval along the paper discharge path RD on the downstream side of the entry roller 21. The intermediate roller 22 is driven by a motor (not shown).

  A plurality of pairs of paper discharge rollers 23 discharge the paper P conveyed by the intermediate roller 22 to the paper discharge tray 3. The plurality of pairs of paper discharge rollers 23 are arranged at a predetermined interval along the paper discharge path RD on the downstream side of the intermediate roller 22. Further, the paper discharge roller 23 is disposed on the upper left side with respect to the paper discharge table 3. The paper discharge roller 23 is driven by a motor (not shown).

  The first switching unit 24 switches the transport path of the paper P between the paper discharge path RD and the reverse path RR. The first switching unit 24 is disposed at a branch point between the paper discharge route RD and the reversal route RR. The first switching unit 24 is driven by a solenoid (not shown).

  The plurality of pairs of forward rollers 25 transport the paper P guided to the reverse route RR by the first switching unit 24 to the reverse roller 26. The plural pairs of forward rollers 25 are arranged at a predetermined interval along the reverse route RR between the first switching unit 24 and the reverse roller 26. The forward roller 25 is driven by a motor (not shown).

  The reverse roller 26 switches back the paper P conveyed by the forward roller 25 and conveys it to the backward roller 27. The reverse roller 26 is arranged along the reverse route RR on the downstream side of the forward roller 25. The reversing roller 26 is configured to be capable of forward and reverse rotation by a motor (not shown) in order to switch back the paper P.

  The plurality of pairs of backward rollers 27 convey the paper P switched back by the reverse roller 26 to the intermediate roller 22 at the most downstream side. The plurality of pairs of return path rollers 27 are disposed between the reversing roller 26 and the most downstream intermediate roller 22 with a predetermined interval along the reversing path RR. The return roller 27 is driven by a motor (not shown).

  The second switching unit 28 guides the paper P conveyed by the forward roller 25 to the reverse roller 26. Further, the second switching unit 28 guides the paper P, which is switched back by the reverse roller 26 and conveyed upward, to the return roller 27. The second switching unit 28 is disposed at a location where the forward path and the return path branch in the reversal path RR.

  The paper discharge sensor 29 detects the paper P discharged from the transport unit 2 to the paper discharge tray 3. The paper discharge sensor 29 is disposed on the upstream side of the most downstream paper discharge roller 23. The paper discharge sensor 29 is composed of, for example, an optical sensor having a light emitting element and a light receiving element.

  The paper discharge tray 3 is a stack on which printed paper P discharged by the paper discharge roller 23 is stacked. The paper discharge table 3 is disposed below the right side with respect to the paper discharge roller 23. As shown in FIG. 3, the sheet stacking surface 3 a of the paper discharge table 3 has a substantially V shape in which both sides in the front-rear direction are higher than the center when viewed from the left-right direction. As a result, the discharged paper P is stacked on the paper discharge tray 3 in a substantially U shape in which both sides in the paper width direction (front-rear direction) orthogonal to the paper discharge direction (left-right direction) are curved upward from the center. The As a result, the paper P can be stiff and the alignment can be improved. The paper discharge table 3 is configured to be movable up and down.

  The elevator unit 4 raises and lowers the paper discharge table 3. The elevator unit 4 has a plurality of elevator arms 30 extending in the front-rear direction. On the elevator arm 30, the paper discharge table 3 is placed. As the elevator arm 30 moves up and down, the sheet discharge table 3 moves up and down.

  The elevating motor 5 generates a driving force for elevating the paper discharge table 3 by the elevator unit 4. The elevator arm 30 and the paper discharge table 3 are raised by the forward drive of the lifting motor 5, and the elevator arm 30 and the paper discharge table 3 are lowered by the reverse drive. The raising / lowering motor 5 is equivalent to the raising / lowering drive part of a claim.

  The upper surface detection sensor 6 is for detecting the upper surface position of the uppermost paper P among the papers P stacked on the paper discharge tray 3. The upper surface detection sensor 6 maintains the upper surface position (the height position of the upper surface of the uppermost sheet P) of the sheets P stacked on the sheet discharge table 3 in the vicinity of the specified height position during the sheet discharge operation. This is used for the upper surface maintaining operation. The specified height position is set in advance as a height position corresponding to an optimum drop distance so that the sheets P dropped from the discharge roller 23 to the discharge table 3 are stacked in an orderly manner. The upper surface detection sensor 6 includes a light emitting unit 6a and a light receiving unit 6b.

  The light emitting unit 6a and the light receiving unit 6b are arranged apart from each other in the left-right direction across a region where the paper P is stacked on the paper discharge table 3. The positions of the light emitting unit 6 a and the light receiving unit 6 b in the front-rear direction are approximately the center in the front-rear direction of the paper discharge tray 3. The light emitting unit 6a is arranged so that the optical axis is at a specified height position in the height direction, and emits light in the right direction toward the light receiving unit 6b. The light receiving unit 6b receives light from the light emitting unit 6a when there is no detection target between the light emitting unit 6a and does not receive light from the light emitting unit 6a when blocked by the detection target. That is, the upper surface detection sensor 6 detects a detection object such as the paper P when the light receiving unit 6b does not receive the light from the light emitting unit 6a.

  The pair of paper discharge wings 7A and 7B bend the paper P discharged from the transport unit 2 to the paper discharge tray 3 into a substantially U shape in which both sides in the paper width direction (front-rear direction) are curved upward from the center. Let As a result, it is possible to smooth the paper P that has been conveyed, and to smoothly discharge the paper onto the paper discharge tray 3. As shown in FIGS. 4 and 5, the paper discharge wings 7 </ b> A and 7 </ b> B are opposed to each other on the downstream side of the paper discharge roller 23 so as to be separated in the front-rear direction across the center line C. The paper discharge wings 7A and 7B respectively have guide surfaces 7a inclined upward toward the downstream side (right side) and the outside (opposite side of the center line C). When the guide surfaces 7a of the paper discharge wings 7A and 7B are in contact with the lower surfaces of both end portions in the paper width direction, the paper P is bent into a substantially U shape. The paper discharge wings 7A and 7B are configured to be movable in conjunction with each other in the front-rear direction symmetrically with respect to the center line C. That is, when the paper discharge wing 7A moves away from the center line C, the paper discharge wing 7B moves away from the center line C. When the paper discharge wing 7A approaches the center line C, the paper discharge wing 7B also moves so as to approach the center line C. To do.

  The paper discharge wing moving motor 8 moves the pair of paper discharge wings 7A and 7B. The driving force of the paper discharge wing moving motor 8 is transmitted to the paper discharge wings 7A and 7B by a paper discharge wing moving mechanism (not shown) so that the paper discharge wings 7A and 7B move. The paper discharge wing moving motor 8 is a pulse motor. The interval between the paper discharge wings 7A and 7B is narrowed by the forward rotation drive of the paper discharge wing movement motor 8, and the interval between the paper discharge wings 7A and 7B is widened by the reverse rotation drive of the paper discharge wing movement motor 8. The paper discharge wing moving motor 8 corresponds to a paper discharge wing drive unit in claims.

  The pair of side fences 9 </ b> A and 9 </ b> B regulates the positions of both ends in the paper width direction of the paper P discharged onto the paper discharge tray 3. The side fences 9 </ b> A and 9 </ b> B are erected on the lower surface of the ceiling portion 13, and are provided in a state of being suspended above the paper discharge tray 3. Further, as shown in FIG. 3, the side fences 9A and 9B are arranged side by side in the front-rear direction with the center line C interposed therebetween. The side fences 9 </ b> A and 9 </ b> B are configured to be able to move (translate) in conjunction with each other in the front-rear direction symmetrically with respect to the center line C. That is, when the side fence 9A moves away from the center line C, the side fence 9B moves away from the center line C, and when the side fence 9A approaches the center line C, the side fence 9B also moves so as to approach the center line C.

  The side fence moving motor 10 moves the pair of side fences 9A and 9B. The driving force of the side fence moving motor 10 is transmitted to the side fences 9A and 9B by a side fence moving mechanism (not shown) so that the side fences 9A and 9B move. The side fence moving motor 10 is a pulse motor. The distance between the side fences 9A and 9B is reduced by the forward rotation driving of the side fence movement motor 10, and the distance between the side fences 9A and 9B is increased by the reverse rotation driving of the side fence movement motor 10. Thereby, the mutual space | interval of the side fences 9A and 9B is adjusted. The side fence moving motor 10 corresponds to a side fence adjusting unit in claims.

  The end fence 11 regulates the position of the right end of the paper P stacked on the paper discharge tray 3. The end fence 11 is erected on the lower surface of the ceiling portion 13 and is disposed so as to be suspended above the paper discharge tray 3. The end fence 11 is configured to be movable in the left-right direction.

  The end fence moving motor 12 moves the end fence 11. The driving force of the end fence moving motor 12 is transmitted to the end fence 11 by an end fence moving mechanism (not shown) so that the end fence 11 moves. The end fence moving motor 12 is a pulse motor. The end fence 11 is moved to the right side by the forward drive of the end fence movement motor 12, and the end fence 11 is moved to the left side by the reverse drive of the end fence movement motor 12.

  The ceiling portion 13 suspends the pair of side fences 9A and 9B and the end fence 11 so as to be movable. The ceiling portion 13 is provided above the paper discharge table 3 so as to face the paper discharge table 3.

  The control unit 14 controls the overall operation of the paper discharge device 1. The control unit 14 includes a storage device such as a CPU, RAM, ROM, and HDD. During the paper discharge operation, the control unit 14 performs control to lower the paper discharge table 3 by the lifting motor 5 in order to maintain the upper surface position of the paper P stacked on the paper discharge table 3. Further, the control unit 14 performs control to move the pair of side fences 9A and 9B so as to reduce the distance between the side fences by the side fence moving motor 10 in accordance with an increase in the number of sheets P stacked on the paper discharge tray 3.

  Next, the operation of the paper discharge device 1 will be described.

  The paper discharge operation of the paper discharge device 1 is performed according to the printing operation in the printing device. The control unit 14 transports the paper P sequentially sent out from the printing apparatus by the transport unit 2 and sequentially discharges the paper P onto the paper discharge tray 3. Here, the control unit 14 receives an instruction from the printing apparatus whether to discharge the paper P sent out from the printing apparatus while maintaining the vertical direction, or to invert the paper P upside down. And the control part 14 controls the conveyance part 2 according to the instruction | indication.

  When the paper P is discharged while keeping the vertical direction of the paper P, the control unit 14 controls the transport unit 2 so that the paper P is transported and discharged along the paper discharge path RD without passing through the reverse path RR. To do. When the paper P is turned upside down and discharged, the control unit 14 controls the transport unit 2 so that the paper P is turned upside down and discharged through the reversing path RR.

  The paper P discharged from the transport unit 2 is sent out by the paper discharge roller 23 and falls through the paper discharge wings 7A and 7B, and is discharged while the position is regulated by the side fences 9A and 9B and the end fence 11. It is loaded on the paper table 3. As the sheets P are sequentially discharged, the number of sheets P stacked on the sheet discharge tray 3 increases, and the stack height gradually increases.

  For this reason, when the height position of the paper discharge tray 3 is fixed, the position of the upper surface of the uppermost sheet P on the paper discharge tray 3 is gradually increased. When the upper surface position of the uppermost sheet P becomes higher and the fall distance of the discharged sheet P changes, the alignment of the sheet on the sheet discharge table 3 may be lowered. Therefore, the paper discharge device 1 performs the upper surface maintaining operation during the paper discharge operation.

  The upper surface maintaining operation during the paper discharge operation will be described.

  First, when starting the paper discharge operation, the control unit 14 performs an upper surface positioning operation. Specifically, the control unit 14 starts to raise the discharge tray 3 by starting the forward drive of the elevating motor 5. Note that before the discharge operation is started, the discharge table 3 is lowered to a predetermined position. Further, the paper P is removed from the paper discharge tray 3, and there is no paper P on the paper discharge tray 3. When the upper surface detection sensor 6 is turned on after the forward drive of the lifting motor 5 is started, the control unit 14 stops the lifting of the discharge table 3 by stopping the lifting motor 5.

  Thereafter, the control unit 14 starts the lowering of the paper discharge table 3 by starting the reverse drive of the lifting motor 5. Then, when the upper surface detection sensor 6 is turned OFF, the control unit 14 stops the lowering of the paper discharge table 3 by stopping the elevating motor 5. Thus, the upper surface positioning operation is completed. By the upper surface positioning operation, the horizontal portion at the center of the paper stacking surface 3a of the paper discharge tray 3 is adjusted so as to be positioned at the specified height position. At this time, the lower ends of the side fences 9 </ b> A and 9 </ b> B are designed to have the same height as both ends in the front-rear direction of the paper discharge tray 3.

  Here, the state in which the upper surface detection sensor 6 is detecting the detection target (the state in which the light from the light emitting unit 6a is blocked by the detection target and the light receiving unit 6b is not receiving light) is ON, and the detection target is detected. The state where the light is not received (the state where the light receiving unit 6b receives the light from the light emitting unit 6a) is set to OFF. When the light receiving unit 6b receives light from the light emitting unit 6a, the light receiving unit 6b outputs a signal, and the control unit 14 determines ON / OFF of the upper surface detection sensor 6 based on the output signal of the light emitting unit 6a.

  After starting the discharge from the transport unit 2 to the discharge table 3, the control unit 14 performs the upper surface maintaining operation. Specifically, when the upper surface detection sensor 6 is turned on, the control unit 14 starts the lowering of the discharge table 3 by starting the reverse drive of the lifting motor 5. Thereafter, when the upper surface detection sensor 6 is turned off, the control unit 14 stops the lowering of the paper discharge table 3 by stopping the elevating motor 5. By repeating this, the upper surface position at the center of the paper P on the paper discharge tray 3 is maintained in the vicinity of the specified height position.

  Here, the change in the upper surface inclination angle according to the increase in the number of sheets P stacked on the paper discharge tray 3 and the change in the gap between the side fence 9 fixed at a position corresponding to the paper size and the paper P are measured. The results are shown in FIG. The upper surface inclination angle is an inclination angle of the upper surface of the uppermost sheet P on the paper discharge tray 3. The inclination angle of the paper stacking surface 3a of the paper discharge tray 3 is 16.5 degrees. The gap between the side fence 9 and the paper P is the distance between the side fence 9 and the end of the uppermost paper P.

  As shown in FIG. 6, as the number of stacked sheets increases, the upper surface inclination angle increases. At the same time, the gap between the side fence 9 and the paper P is increased.

  That is, in the paper discharge device 1, as the number of sheets P stacked on the paper discharge tray 3 increases, the curvature of the paper P at the top of the stacked paper increases as shown in FIG. For this reason, if the positions of the side fences 9A and 9B are the same as those at the start of the paper discharge operation, the gap between the side fences 9A and 9B and the paper P becomes large above the stacked paper as shown in FIG. As a result, the alignment of the paper P may be reduced.

  Therefore, in the paper discharge device 1, during the paper discharge operation, control is performed to narrow the interval between the pair of side fences 9A and 9B in accordance with an increase in the number of sheets P stacked on the paper discharge tray 3.

  The movement control of the side fences 9A and 9B during the paper discharge operation will be described with reference to the flowchart of FIG.

  Here, when the paper discharge operation is started, the control unit 14 arranges the paper discharge wings 7A and 7B, the side fences 9A and 9B, and the end fence 11 according to the size of the paper P to be discharged.

  Specifically, the control unit 14 moves the discharge wings 7A and 7B to the home position by the discharge wing moving motor 8, and then discharges the wing by the number of pulses corresponding to the size of the discharged paper P. The moving motor 8 is driven to rotate forward. Thus, the paper discharge wings 7A and 7B are arranged according to the size of the paper P. The home positions of the paper discharge wings 7A and 7B are detected by a paper discharge wing HP (home position) sensor (not shown).

  Further, the control unit 14 moves the side fences 9A and 9B to the home position by the side fence moving motor 10, and then rotates the side fence moving motor 10 in the normal direction by the number of pulses corresponding to the size of the paper P to be discharged. Drive. Thus, the side fences 9A and 9B are arranged according to the size of the paper P. The home positions of the side fences 9A and 9B are detected by a side fence HP sensor (not shown).

  Further, after the end fence 11 is moved to the home position by the end fence moving motor 12, the control unit 14 drives the end fence moving motor 12 in the normal direction by the number of pulses corresponding to the size of the paper P to be discharged. . Thereby, the end fence 11 is arranged according to the size of the paper P. The home position of the end fence 11 is detected by an end fence HP sensor (not shown).

  When the discharge of the sheet P from the transport unit 2 to the discharge table 3 starts, the control unit 14 starts counting the number of discharged sheets in step S10 in FIG. Specifically, every time the paper P is detected by the paper discharge sensor, the control unit 14 adds 1 to the count of the number of paper discharged.

  Next, in step S20, the control unit 14 determines whether or not the number of discharged sheets has reached the number of side fence adjustments. Here, since the paper discharge operation is started when there is no paper P on the paper discharge tray 3, the number of paper discharges is equal to the number of stacked sheets on the paper discharge tray 3. The number of adjusted side fences is a number set in advance as the number of discharged sheets indicating the timing for performing the operation of narrowing the distance between the pair of side fences 9A and 9B. One or a plurality of side fence adjustment numbers are set as a value of the cumulative number of discharged sheets (the number of stacked sheets on the sheet discharge tray 3) such as 2000 sheets, 3000 sheets, and 3500 sheets.

  When it is determined that the number of discharged sheets has reached the number of adjusted side fences (step S20: YES), in step S30, the control unit 14 determines whether or not the upper surface detection sensor 6 is turned on. Here, the control unit 14 determines that the upper surface detection sensor 6 has been turned ON when the upper surface detection sensor 6 has been stable in an ON state for a predetermined time or longer. When it is determined that the upper surface detection sensor 6 is not turned on (step S30: NO), the control unit 14 repeats step S30.

  When it is determined that the upper surface detection sensor 6 is turned on (step S30: YES), in step S40, the control unit 14 starts the lowering of the discharge table 3 by starting the reverse drive of the elevating motor 5.

  Next, in step S50, the control unit 14 determines whether or not the upper surface detection sensor 6 is turned off. Here, the control unit 14 determines that the upper surface detection sensor 6 has been turned off when the upper surface detection sensor 6 has been stable in the OFF state for a predetermined time or longer. When it is determined that the upper surface detection sensor 6 is not OFF (step S50: NO), the control unit 14 repeats step S50.

  When it is determined that the upper surface detection sensor 6 has been turned off (step S30: YES), in step S60, the control unit 14 stops the lifting motor 5 to end the lowering of the paper discharge tray 3.

  Next, in step S70, the control unit 14 moves the pair of side fences 9A and 9B so as to reduce the distance between them.

  Specifically, the control unit 14 drives the side fence movement motor 10 to rotate forward by a specified number of pulses corresponding to the number of side fence adjustments. As a result, the side fences 9A and 9B move inward (center line C side) by a specified amount of movement. By narrowing the distance between the side fences 9A and 9B in this way, as shown in FIG. 9, even if the curvature of the sheet P is large at the upper part of the stacked sheets on the sheet discharge table 3, the side fences 9A and 9B The gap with the paper P should not be large. When the movement of the side fences 9A and 9B ends, the control unit 14 returns to step S20.

  If it is determined in step S20 that the number of discharged sheets has not reached the number of adjusted side fences (step S20: NO), in step S80, the control unit 14 determines whether or not the discharge of the number of printed sheets has been completed. To do. If it is determined that the number of printed sheets has not been discharged (step S80: NO), the control unit 14 returns to step S20. If it is determined that the number of printed sheets has been discharged (step S80: YES), the control unit 14 ends the series of processes.

  As described above, in the paper discharge device 1, the interval between the pair of side fences 9 </ b> A and 9 </ b> B is narrowed in accordance with an increase in the number of sheets P discharged to the paper discharge tray 3 and stacked on the paper discharge tray 3. . Specifically, the pair of side fences 9A and 9B are moved in directions close to each other to narrow the interval between them. As a result, the paper discharge device 1 can prevent the gap between the side fences 9A and 9B and the paper P from becoming large even when the curvature of the paper P is large above the stacked paper on the paper discharge tray 3. As a result, the paper discharge device 1 can suppress a decrease in the alignment of the paper P stacked on the paper discharge tray 3.

  In the paper discharge device 1, when the interval between the side fences 9A and 9B is narrowed, the side fences 9A and 9B are moved after the paper discharge table 3 is lowered by the upper surface maintaining operation. Thereby, the paper discharge device 1 can avoid the side fences 9A and 9B from colliding with the paper P stacked on the paper discharge tray 3 when the interval between the side fences 9A and 9B is narrowed. As a result, the side fences 9A and 9B and the paper P can be prevented from being damaged.

  In the present embodiment, the movement of the side fences 9A and 9B is started after the lowering of the discharge table 3, but after the start of the lowering of the discharge table 3, that is, the start of the lowering operation of the discharge table 3. At the same time or during the lowering operation, the movement of the side fences 9A and 9B may be started.

  Further, in conjunction with the movement of the pair of side fences 9A and 9B, the pair of paper discharge wings 7A and 7B may be moved so as to narrow the mutual interval. That is, in response to the interval between the pair of side fences 9A and 9B being narrowed, the curvature of the paper P formed by the paper discharge wings 7A and 7B is increased, and the distance between both ends of the paper P in the paper width direction is increased. It may be made smaller.

  In this case, the control unit 14 also moves the paper discharge wings 7A and 7B when moving the side fences 9A and 9B in step S70 of FIG. Specifically, the control unit 14 drives the paper discharge wing moving motor 8 to rotate forward by a specified number of pulses corresponding to the number of adjusted side fences. As a result, the paper discharge wings 7A and 7B are moved inward by a specified movement amount, and the distance between them is reduced. The distance between the discharged paper wings 7A and 7B after the movement is such that the leading edge of the paper P that is curved into a substantially U shape by the action of the paper discharge wings 7A and 7B and discharged to the paper discharge tray 3 is the side fence 9A, The size is set so as not to collide with the left end of 9B.

  Thereby, it is possible to prevent the leading edge of the paper P that passes through the paper discharge wings 7A and 7B and is discharged to the paper discharge tray 3 from colliding with the left ends of the side fences 9A and 9B. As a result, the paper discharge device 1 can prevent paper discharge failure.

(Second Embodiment)
FIG. 10 is an overall schematic diagram of a paper discharge device according to the second embodiment, and FIG. 11 is a block diagram illustrating a configuration of a control system of the paper discharge device according to the second embodiment.

  As shown in FIGS. 10 and 11, the paper discharge device 1 </ b> A according to the second embodiment further includes the configuration of the paper discharge device 1 according to the first embodiment shown in FIGS. 1 and 2. Side fence rotation motors 31A and 31B are provided.

  The side fence rotation motors 31A and 31B rotate the side fences 9A and 9B in the sheet width direction. In the paper discharge device 1A, the side fences 9A and 9B are configured to be rotatable in the paper width direction about the shafts 32A and 32B as shown in FIG. 12 by driving the side fence rotation motors 31A and 31B. Yes. Thereby, the mutual space | interval of the side fences 9A and 9B is adjusted. The shafts 32A and 32B are shafts provided at the upper ends of the side fences 9A and 9B and extending in parallel with the paper discharge direction. The side fence rotation motors 31 </ b> A and 31 </ b> B correspond to a side fence adjustment unit in claims.

  In the second embodiment, instead of moving the side fences 9A and 9B in step S70 of FIG. 8 described in the first embodiment, the control unit 14 uses the side fence rotation motors 31A and 31B to move the side fences. 9A and 9B are rotated by a specified angle. Thereby, as shown in FIG. 13, the space | interval of the side fences 9A and 9B is narrowed.

  In this manner, in the paper discharge device 1A, even if the curvature of the paper P is large at the top of the stacked paper on the paper discharge tray 3, the gap between the paper P at the lower ends of the side fences 9A and 9B is large. Can be prevented. As a result, the paper discharge device 1 </ b> A can suppress a decrease in the alignment of the paper P stacked on the paper discharge tray 3.

  When the side fences 9A and 9B are rotated, the reduction amount of the interval between the upper portions of the side fences 9A and 9B is smaller than that of the lower portion. Therefore, it is possible to prevent the leading end of the discharged paper P from colliding with the left end of the side fences 9A and 9B without reducing the interval between the paper discharge wings 7A and 7B. However, an operation of narrowing the interval between the paper discharge wings 7A and 7B in conjunction with the rotation of the side fences 9A and 9B may be performed.

  Note that the distance between the side fences 9A and 9B may be narrowed by combining the rotation of the side fences 9A and 9B and the movement (parallel movement) of the side fences 9A and 9B. For example, when the inclination of the side fences 9A and 9B reaches a predetermined angle, the distance between the side fences 9A and 9B may be narrowed thereafter.

  If the inclinations of the side fences 9A and 9B become too large, there is a possibility that a problem that the paper P leans against the side fences 9A and 9B may occur. By combining the rotation of the side fences 9A and 9B and the movement of the side fences 9A and 9B as described above, it is possible to reduce the occurrence of such problems and suppress the deterioration of the alignment of the paper P.

  The present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the components without departing from the scope of the invention in the implementation stage. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

DESCRIPTION OF SYMBOLS 1,1A Paper discharge apparatus 2 Conveyance part 3 Paper discharge stand 4 Elevator part 5 Lifting motor 6 Upper surface detection sensor 7A, 7B Paper discharge wing 8 Paper discharge wing movement motor 9A, 9B Side fence 10 Side fence movement motor 11 End fence 12 End Fence moving motor 13 Ceiling part 14 Control part 31A, 31B Side fence rotation motor

Claims (5)

A paper discharge tray on which the discharged paper is stacked in a substantially U shape in which both sides in the paper width direction orthogonal to the paper discharge direction are curved upward from the center;
A pair of side fences that are suspended above the paper discharge tray and regulate the positions of both ends of the paper discharged on the paper discharge tray in the paper width direction;
An elevating drive unit for elevating and lowering the discharge table;
A side fence adjusting unit that adjusts the distance between the pair of side fences;
A control unit that lowers the sheet discharge table by the lift drive unit in order to maintain the upper surface position of the sheets stacked on the sheet discharge table during the sheet discharge operation;
The paper discharge device, wherein the control unit controls the side fence adjustment unit to narrow the interval in accordance with an increase in the number of sheets stacked on the paper discharge table.   The paper discharge device according to claim 1, wherein the side fence adjusting unit adjusts the interval by moving the pair of side fences.   The paper discharge device according to claim 1, wherein the side fence adjusting unit adjusts the interval by rotating the side fences in a paper width direction. A pair of paper discharge wings that bend the paper discharged to the paper discharge tray into a substantially U shape;
A paper discharge wing drive unit that moves the pair of paper discharge wings;
The control unit moves the pair of paper discharge wings so as to reduce a distance between the pair of paper discharge wings by the paper discharge wing driving unit in conjunction with an operation of narrowing the interval by the side fence adjusting unit. The paper discharge device according to any one of 1 to 3.   When the controller performs the operation of narrowing the interval by the side fence adjusting unit, the interval after the start of lowering of the discharge table for maintaining the upper surface position of the paper stacked on the discharge table is set. The paper discharge device according to claim 1, wherein an operation of narrowing the head is started.