JP6068075B2 - Transport device - Google Patents

Description

  The present invention relates to a transport apparatus that performs switchback transport of paper.

  2. Description of the Related Art Conventionally, in a printing apparatus or the like, a conveyance device that performs switchback conveyance to turn a sheet upside down is known.

  In such a transport apparatus, there is a type using a reversing claw to switch between an entry path through which a sheet enters the switchback roller and an exit path through which the sheet is fed from the switchback roller.

  The tip of the reversing claw is biased by a spring to the guide plate on the approach path side. The paper entering the switchback roller passes while pushing down the reverse claw. When the paper entering the switchback roller passes, the reversing claw returns to its original position by the spring force. Thereby, an exit path is secured.

  However, when the above-described reversing claw is used, there is a risk that damage such as breakage of the leading edge of the paper may occur. In particular, in the case of high-speed conveyance or conveyance of a low-stiff sheet, the sheet is easily damaged.

  Further, in order to suppress catching of the leading edge of the paper, the reversing claw is formed in a comb shape. For this reason, a wavy waist is generated on the paper, which may cause noise due to the paper coming into contact with the guide plate of the conveyance path.

  In view of this, there has been proposed a conveyance device that switches the path by using the bending of the conveyance path and the waist of the sheet without using the reversing claw (see, for example, Patent Document 1). In this transport device, the path is switched by utilizing the fact that the rear end of the paper bent along the transport path passes through the guide plate, and the direction of the rear end changes as the paper recovers its shape due to the waist. ing.

JP-A-6-32517

  However, in the conveyance device that does not use the above-described reversing claw, when the paper recovers its shape due to the waist, it may collide with the guide plate on the outlet side, and noise may be generated. In particular, this noise is increased in the case of high-speed conveyance or conveyance of stiff paper.

  The present invention has been made in view of the above, and an object of the present invention is to provide a transport device that can reduce noise.

  In order to achieve the above object, a first feature of the transport device according to the present invention is that a pair of switchback rollers that switchback transports paper that has entered the switchback path from the entrance path and sends it to the exit path, and the entrance A first guide plate for guiding one side of the sheet in the path, a second guide plate for guiding one side of the sheet in the switchback path and the exit path, and control for controlling the switchback roller pair A path that leads from the approach path to the switchback path is a path that is bent at the junction, and the trailing edge of the sheet conveyed by the switchback roller pair passes through the first guide plate. The controller moves to the second guide plate side by the waist of the paper, and the control unit is configured to move the paper before the rear end of the paper passes through the first guide plate. In that to decelerate the conveyance speed of the sheet by the switchback rollers.

  A second feature of the transport apparatus according to the present invention is that the control unit adjusts the transport speed of the sheet by the switchback roller pair when the trailing edge of the sheet exits the first guide plate according to the type of the sheet. There is to do.

  A third feature of the transport device according to the present invention is that a transport direction by the switchback roller pair is inclined toward the second guide plate side with respect to a direction parallel to the second guide plate in transport after switchback. Be in the direction.

  A fourth feature of the transport device according to the present invention is further provided with an adjustment unit that adjusts a transport direction by the switchback roller pair, and the control unit transports the switchback roller pair by a direction according to the type of paper. The adjustment unit is controlled so as to adjust.

  According to the first feature of the transport apparatus according to the present invention, the transport speed of the paper is decelerated before the trailing edge of the paper passes through the first guide plate. Thereby, it is possible to reduce noise caused by the rear end portion of the sheet that has passed through the first guide plate colliding with the second guide plate.

  According to the second feature of the transport apparatus according to the present invention, the transport speed of the paper at the time when the trailing edge of the paper passes through the first guide plate is adjusted according to the type of the paper. Thereby, it is possible to further reduce noise caused by the rear end portion of the sheet that has passed through the first guide plate colliding with the second guide plate.

  According to the third feature of the transport apparatus according to the present invention, the transport direction by the switchback roller pair is inclined toward the second guide plate side with respect to the direction parallel to the second guide plate in the transport after the switchback. It is. Thereby, even when the paper is curled, it is possible to reduce the collision and contact of the switched back paper with the first guide plate. As a result, conveyance failure can be reduced.

  According to the 4th characteristic of the conveying apparatus which concerns on this invention, a conveyance defect can be reduced more by adjusting the conveyance direction by a switchback roller pair according to the kind of paper.

1 is an overall schematic diagram of a paper discharge device provided with a transport device according to an embodiment. FIG. 2 is a block diagram illustrating a configuration of a control system of the paper discharge device illustrated in FIG. 1. It is a block diagram of the principal part of an inversion part. It is explanatory drawing of switching of the conveyance path | route at the time of switchback. It is a block diagram of an adjustment part. It is explanatory drawing of the conveyance direction by a switchback roller pair.

  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.

  FIG. 1 is an overall schematic diagram of a paper discharge device provided with a transport device according to an embodiment of the present invention, FIG. 2 is a block diagram showing the configuration of a control system of the paper discharge device shown in FIG. 1, and FIG. FIG. 4 is a diagram illustrating the switching of the conveyance path during switchback, and FIG. 5 is a diagram illustrating the configuration of the adjustment unit. In the following description, the paper surface direction of FIG. Moreover, as shown in FIG. 1, when viewed from the user, the top, bottom, left, and right are defined as the top, bottom, left, and right directions.

  As shown in FIGS. 1 and 2, the paper discharge device 1 includes a paper discharge unit 2, a paper discharge stand 3, a lift drive unit 4, a pair of side fences 5 </ b> A and 5 </ b> B, an end fence 6, and a fence drive. A unit 7, a carriage 8, and a control unit 9 are provided. In addition, the conveyance apparatus of a claim has a part of the paper discharge unit 2 (a reversing unit 12 described later) and a control unit 9.

  The paper discharge unit 2 receives printed paper sent from a printing device (not shown) connected to the left side of the paper discharge device 1 and discharges it to a paper discharge tray 3. The paper discharge unit 2 includes a paper discharge transport unit 11 and a reversing unit 12.

  Here, a path indicated by a thick line in FIG. 1 is a transport path through which the sheet is transported in the paper discharge unit 2. Among the transport routes, a route indicated by a solid line is a paper discharge route RD, a route indicated by a broken line is a reverse approach route (corresponding to an entry route in claims) RI, a route indicated by a one-dot chain line is indicated by a switchback route RS, and a two-dot chain line The route is a reverse exit route (corresponding to the exit route in the claims) RO. In the following description, upstream and downstream mean upstream and downstream in the transport direction on the transport path.

  The paper discharge transport unit 11 transports and discharges the paper sent from the printing apparatus. As shown in FIGS. 1 and 2, the paper discharge transport unit 11 includes an introduction roller pair 21, an introduction motor 22, a face-up roller pair 23, a rising roller pair 24, a rising motor 25, and a first discharge roller. A pair 26, a second discharge roller pair 27, and a discharge motor 28 are provided.

  The introduction roller pair 21 takes the printed paper from the printing device into the paper discharge device 1. The introduction roller pair 21 is disposed at the most upstream portion 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 introduction motor 22 rotationally drives the introduction roller pair 21, the face-up roller pair 23, and a first reverse approach roller pair 33 described later.

  The face-up roller pair 23 conveys the paper taken from the printing apparatus by the introduction roller pair 21 to the ascending roller pair 24. The face-up roller pair 23 is disposed on the downstream side of the introduction roller pair 21 along the paper discharge path RD.

  The ascending roller pair 24 conveys the sheet conveyed from the face-up roller pair 23 or the second intermediate roller pair 38 described later to the first discharge roller pair 26. The ascending roller pair 24 is disposed on the paper discharge path RD in the vicinity of the downstream side of the junction with the reverse exit path RO.

  The ascending motor 25 drives the ascending roller pair 24 to rotate.

  The first discharge roller pair 26 conveys the sheet conveyed from the ascending roller pair 24 to the second discharge roller pair 27. The first discharge roller pair 26 is disposed on the downstream side of the ascending roller pair 24 along the discharge path RD.

  The second discharge roller pair 27 discharges the sheet conveyed from the first discharge roller pair 26 to the sheet discharge table 3. The second discharge roller pair 27 is disposed at the most downstream part of the discharge path RD.

  The discharge motor 28 rotates the first discharge roller pair 26 and the second discharge roller pair 27.

  The reversing unit 12 performs switchback conveyance for reversing the paper taken into the paper discharge device 1 from the printing device. As shown in FIGS. 1 to 3, the reversing unit 12 includes a path switching flipper 31, a path switching solenoid 32, a first reverse approaching roller pair 33, a second reverse approaching roller pair 34, and a switchback roller pair 35. A switchback motor 36, a first intermediate roller pair 37, a second intermediate roller pair 38, an intermediate transport motor 39, a paper sensor 40, an entry side lower guide plate 41, and an entry side upper guide plate (invoice) , The outlet side upper guide plate (corresponding to the second guide plate of the claims) 43, the outlet side lower guide plate 44, and the adjusting portion 45.

  The path switching flipper 31 switches the paper transport path between the paper discharge path RD and the reverse approach path RI. The route switching flipper 31 is disposed at a branch point between the paper discharge route RD and the reverse approach route RI.

  The path switching solenoid 32 drives the path switching flipper 31.

  The first reverse approach roller pair 33 conveys the sheet guided to the reverse approach path RI by the path switching flipper 31 to the second reverse approach roller pair 34. The first reverse approach roller pair 33 is disposed on the downstream side of the path switching flipper 31 along the reverse approach path RI.

  The second reverse approach roller pair 34 transports the paper transported from the first reverse approach roller pair 33 to the switchback roller pair 35. The second reverse approach roller pair 34 is disposed on the downstream side of the first reverse approach roller pair 33 along the reverse approach path RI.

  The switchback roller pair 35 performs switchback conveyance of the sheet that has entered the switchback path RS from the reverse approach path RI and sends it to the reverse exit path RO. The switchback roller pair 35 is configured to be able to rotate forward and backward in order to perform switchback conveyance of paper. The switchback roller pair 35 is disposed on the switchback path RS in the vicinity of the junction with the reverse approach path RI.

  The switchback motor 36 drives the switchback roller pair 35 to rotate forward or reversely.

  The first intermediate roller pair 37 conveys the paper switched back by the switchback roller pair 35 to the second intermediate roller pair 38. The first intermediate roller pair 37 is disposed on the reverse exit path RO between the switchback roller pair 35 and the ascending roller pair 24.

  The second intermediate roller pair 38 conveys the sheet conveyed from the first intermediate roller pair 37 to the ascending roller pair 24. The second intermediate roller pair 38 is disposed on the downstream side of the first intermediate roller pair 37 along the reverse exit path RO.

  The intermediate conveyance motor 39 rotates the second reverse approach roller pair 34, the first intermediate roller pair 37, and the second intermediate roller pair 38.

  The paper sensor 40 detects the paper conveyed on the reverse approach path RI between the first reverse approach roller pair 33 and the second reverse approach roller pair 34. The paper sensor 40 is an optical sensor.

  As shown in FIG. 3, the entry side lower guide plate 41 guides the lower surface side of the sheet in the reverse entry route RI and the switchback route RS. The approach side lower guide plate 41 is bent downward in the vicinity of the junction of the reversal approach path RI and the switchback path RS.

  The approach-side upper guide plate 42 guides the upper surface side of the sheet in the reverse approach path RI. The entry side upper guide plate 42 is provided substantially parallel to the upper part of the entry side lower guide plate 41.

  The exit-side upper guide plate 43 guides the upper surface side of the sheet in the switchback path RS and the reverse exit path RO. Even in the vicinity of the connection point between the switchback route RS and the reversal exit route RO, it is formed in a flat shape that does not bend.

  The exit-side lower guide plate 44 guides the lower surface side of the sheet in the reverse exit route RO. The outlet side lower guide plate 44 is provided substantially parallel to the outlet side upper guide plate 43. The lower end portion of the outlet side lower guide plate 44 is bent to the opposite side of the outlet side upper guide plate 43 side. Thus, the sheet can smoothly enter between the outlet side upper guide plate 43 and the outlet side lower guide plate 44.

  As shown in FIGS. 2 and 3, the route leading from the reverse approach route RI to the switchback route RS is bent at the junction. The path leading from the switchback path RS to the reversal exit path RO is substantially straight. When the trailing edge of the paper that has entered the switchback path RS from the reverse approach path RI passes through the entry-side upper guide plate 42, the paper bent along the transport path recovers its original shape due to the waist of the paper. . As a result, as shown in FIG. 4, the rear end of the sheet P moves to the outlet side upper guide plate 43 side. As a result, the sheet after the switchback is conveyed through the reverse exit route RO between the exit-side upper guide plate 43 and the exit-side lower guide plate 44. In this way, the transport path is switched at the time of switchback.

  The adjustment unit 45 adjusts the conveyance direction by the switchback roller pair 35. As shown in FIG. 5, the adjustment unit 45 includes an adjustment motor 51, a drive gear 52, a sector gear 53, and a home position (HP) sensor 54.

  The adjustment motor 51 generates a driving force for rotating the sector gear 53. The adjustment motor 51 is a pulse motor.

  The drive gear 52 transmits the driving force of the adjustment motor 51 to the sector gear 53 to rotate the sector gear 53. The drive gear 52 is attached to the output shaft 51 a of the adjustment motor 51.

  The sector gear 53 changes the position of the contact point between the driving roller 35a and the driven roller 35b of the switchback roller pair 35. The sector gear 53 meshes with the drive gear 52. The rotation center of the sector gear 53 coincides with the center of the rotation shaft 55 of the drive roller 35a. A rotation shaft 56 of the driven roller 35 b is rotatably supported at the center of the sector gear 53. When the sector gear 53 rotates, the driven roller 35b moves on the circumference of the driving roller 35a, and these contact points move. The tangential direction at the contact point between the driving roller 35 a and the driven roller 35 b is the conveying direction by the switchback roller pair 35. Accordingly, the conveying direction of the switchback roller pair 35 changes as the contact point between the driving roller 35a and the driven roller 35b moves. Even if the driven roller 35b moves relative to the driving roller 35a, the nip pressure of the switchback roller pair 35 does not change because the distance between the centers thereof is constant.

  Further, the sector gear 53 is provided with a protrusion 53 a that is a detection target of the HP sensor 54.

  The HP sensor 54 detects the home position of the driven roller 35 b by detecting the protrusion 53 a of the sector gear 53.

  The paper discharge tray 3 is a stack on which printed paper discharged by the paper discharge unit 2 is stacked. The paper discharge table 3 is disposed below the right side of the second discharge roller pair 27. The paper discharge table 3 is configured to be movable up and down.

  The elevating drive unit 4 elevates and lowers the paper discharge table 3. The raising / lowering drive part 4 has a motor etc.

  The pair of side fences 5 </ b> A and 5 </ b> B regulates the position in the width direction (front-rear direction) of the paper discharged on the paper discharge tray 3. The side fences 5 </ b> A and 5 </ b> B are provided in a state of being suspended from the fence driving unit 7 above the paper discharge table 3, and are separated from the paper discharge table 3. The side fences 5A and 5B are arranged side by side in the front-rear direction.

  The end fence 6 regulates the position of the front end (right end) of the paper discharged to the paper discharge tray 3. The end fence 6 is provided in a state of being hung from the fence driving unit 7 above the paper discharge table 3 and is separated from the paper discharge table 3.

  The fence drive unit 7 moves the pair of side fences 5A and 5B in a direction to approach each other or a direction to separate them from each other. Moreover, the fence drive part 7 moves the end fence 6 in the left-right direction. The fence drive unit 7 is provided above the paper discharge table 3.

  The carriage 8 is for pulling out the paper discharge tray 3 on which the paper is loaded from the paper discharge device 1. When the paper discharge tray 3 is lowered to the lower limit position, it is placed on the carriage 8.

  The control unit 9 controls the overall operation of the paper discharge device 1. The control unit 9 includes a storage device such as a CPU, RAM, ROM, and HDD. The controller 9 decelerates the sheet conveyance speed before the trailing edge of the sheet exits the entry-side upper guide plate 42 during switchback conveyance.

  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 9 receives an instruction from the printing apparatus whether to discharge the sheet sent out from the printing apparatus while maintaining the vertical direction, or to turn the sheet upside down.

  In the case of discharging the paper sent out from the printing apparatus while keeping the vertical direction as it is, the control unit 9 starts driving the introduction motor 22, the lifting motor 25, and the discharge motor 28. As a result, driving of the introduction roller pair 21, the face-up roller pair 23, the ascending roller pair 24, the first and second discharge roller pairs 26 and 27 is started. Here, the control unit 9 drives the conveyance speed of each of these roller pairs to be the same as the speed V1 at which the printing apparatus feeds the paper.

  Further, the controller 9 sets the path switching flipper 31 in the direction in which the sheet is guided from the introduction roller pair 21 to the face-up roller pair 23 by the path switching solenoid 32. Further, the control unit 9 uses the fence driving unit 7 to adjust the positions of the pair of side fences 5A and 5B and the end fence 6 according to the sheet size.

  When the paper enters the paper discharge path RD from the printing apparatus, the paper is guided to the face-up roller pair 23 by the path switching flipper 31 while being conveyed by the introduction roller pair 21. Then, the sheet is conveyed by the face-up roller pair 23, the raising roller pair 24, the first and second discharge roller pairs 26 and 27, and discharged to the sheet discharge table 3.

  At this time, at the timing when the sheet passes through the face-up roller pair 23, the control unit 9 changes the conveying speed by the ascending roller pair 24, the first and second discharge roller pairs 26, 27 to a discharge speed V2 that is higher than the introduction speed V1. And accelerate.

  Thereafter, the control unit 9 returns the conveyance speed of the ascending roller pair 24 from V2 to V1 at the timing when the sheet passes through the ascending roller pair 24. Then, at the timing when the sheet passes through the second discharge roller pair 27, the control unit 9 returns the conveyance speed by the first and second discharge roller pairs 26, 27 from V2 to V1.

  Here, the control unit 9 determines the timing for changing the conveyance speed based on the detection timing of the paper by a plurality of sensors (not shown).

  On the other hand, when the paper is turned upside down and discharged, the control unit 9 starts driving the introduction motor 22, the lifting motor 25, the discharge motor 28, the switchback motor 36, and the intermediate conveyance motor 39. Accordingly, the introduction roller pair 21, the ascending roller pair 24, the first and second discharge roller pairs 26 and 27, the first and second reverse approach roller pairs 33 and 34, the switchback roller pair 35, the first and second intermediate portions Driving of the roller pair 37, 38 is started.

  Here, the control unit 9 drives the conveyance speed by the introduction roller pair 21 and the first reverse entry roller pair 33 to be the introduction speed V1. Further, the control unit 9 includes the ascending roller pair 24, the first and second discharge roller pairs 26 and 27, the second reverse approach roller pair 34, the switchback roller pair 35, and the first and second intermediate roller pairs 37 and 38. The conveyance speed is driven so as to be a reversal speed V3 higher than the introduction speed V1 and the discharge speed V2.

  Further, the control unit 9 sets the path switching flipper 31 in the direction in which the sheet is guided to the reverse approach path RI by the path switching solenoid 32. Further, the control unit 9 uses the fence driving unit 7 to adjust the positions of the pair of side fences 5A and 5B and the end fence 6 according to the sheet size.

  Further, the control unit 9 adjusts the conveyance direction by the switchback roller pair 35 by the adjustment unit 45. Specifically, as shown in FIG. 6, the controller 9 causes the conveyance direction by the switchback roller pair 35 after the switchback indicated by the arrow 61 to be parallel to the outlet-side upper guide plate 43 indicated by the arrow 62. On the other hand, it adjusts so that it may become the direction inclined to the exit side upper guide plate 43 side. The control unit 9 adjusts the conveyance direction by the switchback roller pair 35, that is, the inclination angle θ in FIG. 6 according to the type of paper. Specifically, the slanted paper such as thin paper has a larger inclination angle θ than the stiff paper. The controller 9 adjusts the tilt angle θ by driving the adjustment motor 51. At this time, the control unit 9 controls the tilt angle θ by the number of drive pulses of the adjustment motor 51 from the home position of the driven roller 35b.

  When the paper enters the paper discharge path RD from the printing apparatus, the paper is guided to the reverse approach path RI by the path switching flipper 31 while being conveyed by the introduction roller pair 21. Then, the sheet is conveyed by the first and second reverse approach roller pairs 33 and 34 and the switchback roller pair 35. Here, while the conveyance speed by the first reverse entry roller pair 33 is V1, the conveyance speed by the second reverse entry roller pair 34 and the switchback roller pair 35 is the reversal speed V3 larger than V1, so the paper Is accelerated when it reaches the second reverse entry roller pair 34.

  Here, the control unit 9 decelerates the sheet conveyance speed from the reverse speed V3 before the trailing edge of the sheet passes through the entry-side upper guide plate 42. Specifically, the control unit 9 determines that when a predetermined time elapses after the trailing edge of the paper passes through the paper sensor 40 and the paper sensor 40 is switched from ON (paper detection) to OFF (paper non-detection), The conveyance motor 39 and the switchback motor 36 are controlled to start decelerating the conveyance speed. The deceleration start timing and the deceleration acceleration are set according to the conveyance speed Va (<V3) by the switchback roller pair 35 at the time when the trailing edge of the sheet passes through the entry-side upper guide plate 42.

  The transport speed Va is set according to the type of paper. Specifically, for a stiff paper such as a thick paper, the transport speed Va is set to be lower than that for a stiff paper such as a lightweight paper.

  Thereafter, the control unit 9 stops the switchback motor 36. The switchback roller pair 35 stops in a state where the rear end portion of the sheet is nipped.

  Next, the control unit 9 starts the reverse drive of the switchback motor 36. As a result, the switchback roller pair 35 starts reverse driving, and the sheet is conveyed to the first intermediate roller pair 37. The conveyance speed by the switchback roller pair 35 and the first and second intermediate roller pairs 37 and 38 after the start of reverse rotation driving is set to the reverse speed V3.

  The switched-back paper is conveyed by the first and second intermediate roller pairs 37 and 38, the ascending roller pair 24, and the first and second discharge roller pairs 26 and 27, and is discharged to the paper discharge tray 3.

  At this time, the controller 9 changes the conveying speed of the ascending roller pair 24, the first and second discharge roller pairs 26 and 27 from the reverse speed V3 to the discharge speed V2 at the timing when the sheet passes through the second intermediate roller pair 38. And decelerate.

  Thereafter, the control unit 9 returns the conveyance speed of the ascending roller pair 24 from V2 to V3 at the timing when the sheet passes through the ascending roller pair 24. Then, at the timing when the sheet passes through the second discharge roller pair 27, the control unit 9 returns the conveyance speed by the first and second discharge roller pairs 26, 27 from V2 to V3.

  Here, the control unit 9 determines the timing for changing the conveyance speed based on the detection timing of the paper by a plurality of sensors (not shown).

  As described above, in the paper discharge device 1, during the switchback conveyance, the paper conveyance speed is reduced before the trailing edge of the paper passes through the entry-side upper guide plate 42. As a result, it is possible to reduce noise caused by the rear end portion of the sheet that has passed through the entry-side upper guide plate 42 colliding with the exit-side upper guide plate 43.

  In the paper discharge device 1, the paper transport speed Va at the time when the rear end of the paper passes through the entry-side upper guide plate 42 is adjusted according to the type of paper. Specifically, the conveyance speed Va is decreased as the paper is stiffer. The stronger the sheet, the easier it is to collide with the exit-side upper guide plate 43 when it passes through the entry-side upper guide plate 42, and the collision sound tends to increase. Therefore, noise can be further reduced by reducing the conveyance speed Va for a stiffer sheet.

  In the paper discharge device 1, the conveyance direction by the switchback roller pair 35 after the switchback is inclined to the outlet side upper guide plate 43 side with respect to the direction parallel to the outlet side upper guide plate 43. I have to. As a result, even when the paper is curled, it is possible to reduce the contact of the switched back paper with the entry-side upper guide plate 42. As a result, conveyance failure can be reduced.

  In the paper discharge device 1, the conveyance direction (tilt angle θ) by the switchback roller pair 35 is adjusted according to the type of paper. Specifically, the inclination angle θ is increased as the paper is weaker. The weaker the paper, the more likely it is to curl, and it is easier to collide and come into contact with the entry-side upper guide plate 42 after switchback. Therefore, the conveyance failure can be further reduced by increasing the inclination angle θ for the paper with lower stiffness.

  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.

DESCRIPTION OF SYMBOLS 1 Paper discharge apparatus 2 Paper discharge part 9 Control part 12 Reversing part 35 Switchback roller pair 41 Entrance side lower guide plate 42 Entrance side upper guide plate 43 Exit side upper guide plate 44 Exit side lower guide plate 45 Adjustment part RI Reverse approach path RS Switchback route RO Reverse exit route

Claims (3)

A pair of switchback rollers that carry back the paper that has entered the switchback path from the entry path and send it to the exit path;
A first guide plate for guiding one side of the sheet in the approach path;
A second guide plate for guiding one side of the sheet in the switchback path and the exit path;
An adjustment unit for adjusting a conveyance direction by the switchback roller pair;
A control unit that controls the switchback roller pair and the adjustment unit ;
A path that leads from the approach path to the switchback path is a path that is bent at the junction, and when the rear end of the sheet conveyed by the switchback roller pair passes through the first guide plate, It moves to the second guide plate side,
The control unit controls the adjustment unit to adjust the conveyance direction by the switchback roller pair according to the type of paper,
Further, the control unit decelerates the sheet conveying speed by the switchback roller pair before the trailing edge of the sheet passes through the first guide plate.   2. The transport according to claim 1, wherein the control unit adjusts a transport speed of the sheet by the switchback roller pair at a time point when a rear end of the sheet passes through the first guide plate according to a type of the sheet. apparatus. The controller controls the adjustment unit so that a conveyance direction by the switchback roller pair is a direction inclined toward the second guide plate with respect to a direction parallel to the second guide plate in the conveyance after the switchback. conveying apparatus according to claim 1 or 2, characterized in that control.