Sheet discharge device and sheet post-processing device equipped therewith, and image forming system

Abstract

To provide an image formation device comprising a sheet discharge device capable of adjusting a projection amount of a projection member with a simple configuration.SOLUTION: A sheet discharge device comprises a pair of discharge rollers, a loading tray, a projection member and a movement mechanism. The projection member is supported reciprocatingly between a projection position and a retreat position. The movement mechanism includes a rotation shaft, a holding member connected to the rotation shaft, and a rack-and-pinion mechanism constituted by containing a pinion gear and a rack gear. A narrow region containing a narrow gear and a notched part is provided at least at a part of a movement direction of the rack gear. The pinion gear can slide between an engagement position to be engaged with the narrow gear and a release position facing the notched part for releasing meshing with the narrow gear. The projection member, in a state where the pinion gear is at the release position, can move relatively to the pinion gear in the movement direction.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The present invention relates to a sheet discharging device, a sheet post-processing device including the same, and an image forming system.

Background Art

[0002] Conventionally, there is an image forming system including an image forming apparatus (such as a copying machine or a printer) and a sheet post-processing device disposed on the downstream side of the image forming apparatus. The sheet post-processing device can execute predetermined post-processing such as binding processing and punch hole forming processing. Binding processing is post-processing in which a plurality of sheets (recording media such as printing paper and envelopes) on which an image is formed by an image forming apparatus are stacked in a bundle and the sheet bundle is stapled together. Punch hole forming processing is post-processing in which a punch hole (perforation) is made in a sheet or a sheet bundle by a punch hole forming device.

[0003] Such a sheet post-processing device is equipped with a sheet discharging device (Patent Document 1). The sheet discharging device of Patent Document 1 includes a pair of discharging rollers, a stacking tray, a plurality of protruding members, and a moving mechanism. The pair of discharging rollers discharges the sheet that has been post-processed. The stacking tray stacks the sheets discharged by the pair of discharging rollers.

[0004] Each protruding member is arranged linearly along the axial direction of the pair of discharging rollers. The protruding member is provided above the stacking tray. Further, the protruding member is supported so as to be reciprocally movable between a protruding position and a retracted position. The protruding position is a position where the sheet discharged by the pair of discharging rollers contacts the upper surface of the protruding member. The retracted position is a position retracted to the upstream side of the pair of discharging rollers from the contact position.

[0005] The moving mechanism reciprocates the protruding member between a moving position and a retracted position. Such a moving mechanism comprises a rotating shaft and a plurality of gears. The rotating shaft extends parallel to the central axis of the discharge roller pair. The plurality of gears consist of a pinion gear supported by the rotating shaft and a rack gear formed on the protruding member. The pinion gear and the rack gear are engaged. As the rotating shaft rotates, the protruding member moves via the pinion gear and the rack gear.

[0006] The sheets discharged by the discharge roller pair are first loaded onto each protruding member at a protruding position, and then loaded onto a loading tray. By first loading the sheets onto the protruding members, the downstream end of the sheet in the discharge direction is prevented from sagging, allowing it to be loaded onto the loading tray. Such a sheet discharge device can also be installed around the discharge port from which sheets are discharged, such as in an image forming apparatus. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2005-263475 [Overview of the project] [Problems that the invention aims to solve]

[0008] Incidentally, the moving mechanism for the sheet discharge device described above engages the pinion gear and rack gear during the assembly of the sheet post-processing device. If the pinion gear and rack gear are engaged and the sheet post-processing device is assembled with the positions of each protruding member misaligned in the direction of movement, a misalignment will occur in the protrusion amount of each protruding member. If a misalignment occurs in the protrusion amount of each protruding member, there is a risk that the sheets loaded on the protruding members will not be properly aligned and will be loaded into the sheet loading section. Here, because the rack gear and pinion gear of the protruding member are engaged, if one protruding member is moved to adjust the protrusion amount of each protruding member, the pinion gear rotates along with its axis of rotation. As a result, the other protruding member also moves simultaneously, making it impossible to adjust the protrusion amount of each protruding member individually. For this reason, it was necessary to disassemble the moving mechanism in order to adjust the protrusion amount of each protruding member individually, which was cumbersome.

[0009] The present invention aims to provide a sheet discharge device that allows for easy adjustment of the protrusion amount of a protruding member with a simple configuration, a sheet post-processing device equipped therewith, and an image forming system. [Means for solving the problem]

[0010] To achieve the above objective, the first configuration of the present invention provides a sheet discharge device comprising a pair of discharge rollers, a loading tray, a protruding member, and a moving mechanism. The pair of discharge rollers discharges sheets from a discharge port. The loading tray is positioned downstream of the pair of discharge rollers with respect to the sheet discharge direction, and the sheets discharged by the pair of discharge rollers are loaded onto it. The protruding member protrudes from the discharge port above the loading tray and is supported to reciprocate between a protruding position in which the leading edge of the sheet discharged by the pair of discharge rollers contacts the upper surface and guides it in the discharge direction, and a retracted position where it is retracted from above the loading tray. The moving mechanism moves the protruding member between the protruding position and the retracted position. The moving mechanism includes a rotatably supported rotating shaft extending in a width direction perpendicular to the discharge direction, a holding member connected to the rotating shaft and movably holding the protruding member, and a rack and pinion mechanism comprising a pinion gear supported on the rotating shaft and a rack gear consisting of a number of gear teeth formed on the surface of the protruding member facing the pinion gear and arranged along the direction of movement of the protruding member. At least a portion of the rack gear's direction of movement is provided with a narrow region including a narrow gear formed by cutting out a portion of the gear teeth in the axial direction, and the notch. The pinion gear is slidable in the narrow region between a meshing position in which it engages with the narrow gear and a disengagement position in which it faces the notch and disengages from the narrow gear, and the protruding member is movable relative to the pinion gear in the direction of movement when the pinion gear is in the disengagement position. [Effects of the Invention]

[0011] According to the first configuration of the present invention, the pinion gear and the rack gear can be separated and disengaged from each other while the pinion gear is in the release position. Even if one protruding member is shifted in the direction of movement in this state, the rotation axis does not rotate because the pinion gear is separated from the rack gear, and the other protruding members do not rotate either. Therefore, the position of the protruding member in the direction of movement, i.e., the amount of protrusion, can be adjusted in this state. Furthermore, since the pinion gear can move between the drive position and the separated position without disassembling the movement mechanism, the adjustment of the amount of protrusion can be made less complicated. Thus, a sheet discharge device can be provided that allows for easy adjustment of the amount of protrusion of the protruding member with a simple configuration. [Brief explanation of the drawing]

[0012] [Figure 1] Schematic diagram of an image forming system S including an image forming apparatus 200 and a sheet post-processing device 5 according to an embodiment of the present invention. [Figure 2] Side cross-sectional view showing the internal structure of the sheet post-processing device 5. [Figure 3] Figure 2 is a partial cross-sectional view showing the structure around the processing tray 8. [Figure 4] Perspective view showing the structure around the protruding member 13 of the sheet discharge device 10. [Figure 5] Side view of the support holder 20, taken from the side in the axial direction. [Figure 6] Side view of the structure near the protruding member 13 of the sheet discharge device 10, as seen from the downstream side in the sheet discharge direction. [Figure 7] A perspective view showing an enlarged view of the structure around the protruding member 13. [Figure 8] A plan view showing an enlarged view of the structure around the protruding member 13 when the pinion gear 27 is in the drive position P3. [Figure 9] A perspective view showing an enlarged view of the structure around the tip of the protruding member 13. [Figure 10] A perspective view showing an enlarged view of the structure around the tip of the rack gear 31. [Figure 11] Plan view showing a modified example of the sheet discharge device 10 according to the embodiment.

Best Mode for Carrying Out the Invention

[0013] FIG. 1 is a schematic diagram of an image forming system S including an image forming apparatus 200 and a sheet post-processing apparatus 5 according to an embodiment of the present invention. The image forming system S includes the image forming apparatus 200 and the sheet post-processing apparatus 5.

[0014] The image forming apparatus 200 is a so-called multifunction device corresponding to monochrome, having functions such as printing, scanning (image reading), facsimile transmission, etc. As shown in FIG. 1, on the upper surface of the main body 201, a document conveyance unit 203 is placed. Inside the main body 201 below the document conveyance unit 203, an image reading unit 204 is provided. An image of a document stacked on the document conveyance unit 203 or an image of a document placed on a contact glass (not shown) on the upper surface of the image reading unit 204 is read by the image reading unit 204.

[0015] The image forming apparatus 200 further includes a sheet feeding unit 205, a sheet conveyance unit 206, an exposure unit 207, an image forming unit 208, a transfer unit 209, a fixing unit 210, a sheet discharging unit 211, a relay unit 212, and a main body control unit 213.

[0016] The sheet feeding unit 205 accommodates a plurality of sheets P and separates and feeds out the sheets P one by one during printing. The sheet conveyance unit 206 conveys the sheet P sent out from the sheet feeding unit 205 to the transfer unit 209 and the fixing unit 210, and further distributes the sheet P after fixing to the sheet discharging unit 211 or the relay unit 212. The exposure unit 207 irradiates the image forming unit 208 with laser light controlled based on image data.

[0017] The image forming unit 208 includes a photosensitive drum 2081 which is an image carrier, and a developing device 2082. In the image forming unit 208, an electrostatic latent image of the document image is formed on the surface of the photosensitive drum 2081 by the laser light irradiated from the exposure unit 207. The developing device 2082 supplies toner to this electrostatic latent image for development and forms a toner image. The transfer unit 209 transfers the toner image on the surface of the photosensitive drum 2081 formed by the image forming unit 208 to the sheet P. The fixing unit 210 heats and presses the sheet P onto which the toner image has been transferred to fix the toner image on the sheet P.

[0018] The sheet P after fixing is sent to the sheet discharge unit 211 or the relay unit 212. The sheet discharge unit 211 is disposed below the image reading unit 204. The sheet discharge unit 211 has an opening at the front, and the printed paper (printed matter) is taken out from the front side. The relay unit 212 is disposed below the sheet discharge unit 211. The downstream end in the paper conveyance direction of the relay unit 212 is connected to the sheet post-processing device 5. The printed paper (printed matter) sent to the relay unit 212 passes through the relay unit 212 and is conveyed to the sheet post-processing device 5.

[0019] The main body control unit 213 includes a CPU, an image processing unit, a storage unit, and other electronic circuits and electronic components not shown. The CPU controls the operations of the respective components provided in the image forming apparatus 200 based on the control programs and data stored in the storage unit, and performs processes related to the functions of the image forming apparatus 200. Each of the sheet feeding unit 205, the sheet conveyance unit 206, the exposure unit 207, the image forming unit 208, the transfer unit 209, and the fixing unit 210 receives individual commands from the main body control unit 213 and cooperates to perform printing on the sheet P. The storage unit is composed of a combination of a non-volatile storage device such as a program ROM (Read Only Memory) and a data ROM not shown, and a volatile storage device such as a RAM (Random Access Memory).

[0020] The sheet post-processing device 5 is detachably connected to the side of the image forming apparatus 200. The sheet post-processing device 5 comprises a post-processing housing 50, a sheet transport path 42, a processing tray 8, a perforation processing unit 61, a staple processing unit 62, a transport roller pair 71, an intermediate roller pair 72, a first sheet detection unit S1, a discharge roller pair 73, a second sheet detection unit S2, a sheet discharge device 10, and a post-processing control unit 100, all of which are located within the post-processing housing 50.

[0021] A sheet loading entrance 41 is provided on the side of the post-processing housing 50 facing the image forming apparatus 200. The sheet P that has passed through the relay section 212 is loaded into the sheet loading entrance 41 and into the sheet post-processing device 5.

[0022] The sheet transport path 42 extends from the sheet loading entrance 41 to above the processing tray 8 in a direction away from the image forming apparatus 200 (to the left in Figure 1). The processing tray 8 is capable of temporarily loading sheets P onto its upper surface. The sheet transport path 42 loads the sheets P loaded from the sheet loading entrance 41 onto the upper surface of the processing tray 8.

[0023] The processing tray 8 is inclined so as to have a downward slope from the downstream end to the upstream end in the sheet conveying direction. The processing tray 8 has a bundle discharge member 81. The bundle discharge member 81 is provided at the upstream end of the processing tray 8 with respect to the sheet conveying direction.

[0024] The bundle discharge member 81 supports the upstream end (rear end) of the sheet bundle. The bundle discharge member 81 is fixed to a drive belt (not shown) located on the back side of the processing tray 8, and a portion of it protrudes in an L-shape when viewed from the side from the mounting surface of the processing tray 8. By rotating the drive belt by the post-processing control unit 100, the bundle discharge member 81 reciprocates along the mounting surface of the processing tray 8 in the sheet conveying direction.

[0025] The perforation unit 61 is positioned between the sheet entrance 41 and the downstream end of the sheet transport path 42 in the sheet transport direction. The perforation unit 61 performs perforation on the sheet P being transported along the sheet transport path 42. Perforation is the process of forming punch holes (binding holes). Here, punch holes are made along one side edge in the width direction of the sheet, perpendicular to the sheet transport direction.

[0026] The stapling unit 62 is located below the sheet transport path 42 and upstream of the sheet transport direction of the processing tray 8. The stapling unit 62 performs stapling (binding) on ​​the bundle of sheets P loaded on the processing tray 8. Stapling is the process of binding the bundle of sheets P with staples. In this case, so-called edge binding is performed, where the corners or ends of the sheet bundle are bound with staples.

[0027] Figure 2 is a side cross-sectional view showing the internal structure of the sheet post-processing device 5. Figure 3 is a partial cross-sectional view showing the structure around the processing tray 8 in Figure 2. As shown in Figures 2 and 3, the conveying roller pair 71, intermediate roller pair 72, and discharge roller pair 73 are arranged in that order from the upstream side in the sheet conveying direction.

[0028] The transport roller pair 71 is located adjacent to the downstream side of the perforation processing unit 61 with respect to the sheet transport direction. The transport roller pair 71 transports the sheet after perforation, or the sheet that has not been perforated, to the downstream side in the sheet transport direction (direction of arrow H11 in Figure 2).

[0029] The intermediate roller pair 72 is positioned at the downstream end of the sheet transport path 42 with respect to the sheet transport direction. The intermediate roller pair 72 is located above the upstream end (right end in Figure 2) of the processing tray 8. The intermediate roller pair 72 discharges the sheets P that have been transported from the sheet inlet 41 into the sheet transport path 42 onto the processing tray 8.

[0030] The intermediate roller pair 72 consists of a first drive roller 721 and a first driven roller 722. The first drive roller 721 is connected to a drive source such as a motor (not shown) and its rotation is controlled by the post-processing control unit 100. The first driven roller 722 forms a first nip section 72N that presses against the first drive roller 721 with a predetermined nip pressure to nip and transport the sheet. The first driven roller 722 rotates in conjunction with the first drive roller 721.

[0031] The first sheet detection unit S1 is positioned immediately downstream of the intermediate roller pair 72 with respect to the sheet discharge direction. The first sheet detection unit S1 is a sensor that optically detects sheets and detects when the leading edge of a sheet being transported by the transport roller pair 71 enters the intermediate roller pair 72. The first sheet detection unit S1 also detects when a sheet being transported by the intermediate roller pair 72 has passed through the intermediate roller pair 72.

[0032] The discharge roller pair 73 is positioned downstream of the intermediate roller pair 72 with respect to the sheet discharge direction. The discharge roller pair 73 overlaps with the downstream end of the processing tray 8 with respect to the sheet discharge direction.

[0033] The discharge roller pair 73 consists of a second drive roller 731 (discharge roller) and a second driven roller 732 that presses against the second drive roller 731 with a predetermined nip pressure. The second drive roller 731 and the second driven roller 732 form a second nip section 73N that nips and conveys the sheet P. The second nip section 73N is released by a nip release mechanism (not shown) when stapling is performed by the staple processing section 62. The sheet P is loaded onto the processing tray 8 with the second nip section 73N released. The stapled sheet bundle is discharged to the sheet discharge device 10 by the discharge roller pair 73 with the second nip section 73N restored, or by the bundle discharge member 81.

[0034] The second drive roller 731 is supported by the drive roller shaft 731a and rotates together with the drive roller shaft 731a. A drive source such as a motor is connected to the drive roller shaft 731a (not shown), and its rotation is controlled by the post-processing control unit 100. When the drive roller shaft 731a rotates, the two second drive rollers 731 rotate simultaneously together with the drive roller shaft 731a.

[0035] The second sheet detection unit S2 is located immediately downstream of the discharge roller pair 73. The second sheet detection unit S2 consists of an actuator and a photosensor (both not shown), and is capable of detecting whether a sheet is being discharged and whether the rear end of the sheet has passed the discharge roller pair 73.

[0036] The sheet discharge device 10 includes a sheet receiving wall 11b, a loading tray 11, an upper surface detection sensor S3, a lower limit detection sensor S4, and a tray lifting drive unit 113. In addition to the above configuration, the sheet discharge device 10 also includes a protruding member 13, a sheet holding member 14, a paddle member 15, a support holder 20 (holding member), and a moving mechanism 26, the details of which will be described later.

[0037] The sheet receiving wall 11b constitutes the side of the post-processing housing 50 opposite to the image forming apparatus 200. The loading tray 11 is positioned downstream of the discharge roller pair 73 with respect to the sheet discharge direction. The loading tray 11 is supported so as to be able to move up and down relative to the sheet receiving wall 11b via the tray lifting drive unit 113. The loading tray 11 has a sheet loading surface 11a formed on its upper surface. The sheet loading surface 11a is inclined to move upward as it moves away from the sheet receiving wall 11b. The upstream end of the sheet loading surface 11a with respect to the sheet discharge direction is located below the discharge roller pair 73.

[0038] The loading tray 11 is the final discharge location for sheets in the sheet post-processing device 5. Sheet bundles that have completed stapling in the processing tray 8 are discharged toward the loading tray 11 by the discharge roller pair 73 and loaded onto the sheet loading surface 11a. If stapling is not performed by the stapling processing device 62, the sheets P are transported to the loading tray 11 without being loaded onto the processing tray 8. The sheet receiving wall 11b catches the upstream end (rear end) of the sheet as it slides down along the sheet loading surface 11a.

[0039] The top surface detection sensor S3 is located slightly downstream of the upstream end of the loading tray 11 with respect to the sheet discharge direction. It is a photosensor that detects the top surface of the sheet P loaded on the sheet loading surface 11a.

[0040] The lower limit detection sensor S4 is positioned in the post-processing housing 50 below the lower limit position of the loading tray 11. The lower limit detection sensor S4 is a photosensor similar to the upper surface detection sensor S3, and can detect that the loading tray 11 has descended to its lower limit position when the optical path of the detection unit is blocked by the flag 11c protruding from the loading tray 11.

[0041] The tray lifting drive unit 113 is connected to the loading tray 11 via rails and guides (not shown), and based on the detection results of the upper surface detection sensor S3 and the lower limit detection sensor S4, a drive source such as a motor (not shown) performs a lifting operation (positioning) of the loading tray 11 according to the amount of sheets loaded on the sheet loading surface 11a. The lifting operation of the loading tray 11 is performed every predetermined number of sheets (e.g., 10 sheets) or every predetermined time interval (e.g., every few seconds). This maintains the uppermost position of the sheets on the sheet loading surface 11a at a constant height.

[0042] The post-processing control unit 100 includes a CPU (not shown) and other electronic circuits and components (not shown). The post-processing control unit 100 is communicated with the main unit control unit 213. The post-processing control unit 100 receives commands from the main unit control unit 213 and uses the CPU to control the operation of each component (punching unit 61, stapling unit 62, transport roller pair 71, intermediate roller pair 72, discharge roller pair 73, processing tray 8, sheet discharge device 10, etc.) provided in the sheet post-processing device 5 based on control programs and data stored in the memory unit, thereby performing processing related to the functions of the sheet post-processing device 5.

[0043] As shown in Figure 3, the sheet retaining member 14 is positioned on the upstream side of the loading tray 11 in the sheet discharge direction. The sheet retaining member 14 is positioned below the drive roller shaft 731a. Two sheet retaining members 14 are positioned in the sheet width direction of the loading tray 11 with a predetermined distance between them.

[0044] The sheet holding member 14 is supported at its lower end so as to be able to swing around a pivot shaft 14a that extends along the sheet width direction. The sheet holding member 14 swings around the pivot shaft 14a with one upper end as the free end in the sheet discharge direction. The swing of the sheet holding member 14 occurs between a position where it presses down on the upstream part of the sheet in the discharge direction loaded on the loading tray 11 from above, and a position where it releases the pressure on the sheet. The swing of the sheet holding member 14 is controlled by the post-processing control unit 100.

[0045] The sheet holding member 14 presses down on the rear end of the sheet P loaded on the sheet loading surface 11a from above. This allows the rear end of the sheet to be pressed down and the curl to be corrected, even if the sheet being discharged is curled.

[0046] Multiple paddle members 15 (four in this case) are provided coaxially with the drive roller shaft 731a. The paddle members 15 rotate independently of the drive roller shaft 731a. The four paddle members 15 are connected to a drive source such as a motor (not shown) and their rotation is controlled by the post-processing control unit 100.

[0047] As shown in Figure 3, the sheet holding member 14 is stopped in a position that does not protrude toward the loading tray 11 side before the sheet discharge operation begins, so as not to obstruct the discharge of the sheet P. Similarly, the paddle member 15 is waiting in a position that does not protrude toward either the processing tray 8 side or the loading tray 11 side before the sheet operation begins, so as not to obstruct the discharge of the sheet P.

[0048] The post-processing control unit 100 starts rotating the paddle member 15 after the rear end of the sheet P (the upstream end in the sheet discharge direction) has passed the second nip section 73N and before the sheet P is loaded onto the sheet loading surface 11a. The paddle member 15 then contacts the rear end of the sheet P discharged from the discharge roller pair 73 and strikes the vicinity of the rear end of the sheet P from above, pushing it downward toward the sheet loading surface 11a.

[0049] As the paddle member 15 rotates further from this state, it pulls the sheet P along the loading tray 11 toward the upstream side in the discharge direction of the sheet P, while pressing the area near the rear end of the sheet P toward the sheet receiving wall 11b of the loading tray 11.

[0050] Furthermore, the paddle member 15 begins to rotate, and before the paddle member 15 passes the upstream end of the loading tray 11 in the sheet discharge direction, the sheet holding member 14 begins to swing. The sheet holding member 14 then moves to a holding position that presses down on the upstream end of the sheets loaded on the loading tray 11 in the discharge direction from above.

[0051] Then, when the sheet loading operation by the sheet post-processing device 5 is completed, the upstream end of the sheet P in the discharge direction comes into contact with the sheet receiving wall 11b provided on the upstream side of the loading tray 11 in the sheet discharge direction. As a result, the sheet P is aligned to a predetermined position on the loading tray 11.

[0052] Figure 4 is a perspective view showing the structure around the protruding member 13 of the sheet discharge device 10. As shown in Figures 3 and 4, the protruding member 13 is a rod-shaped member that extends in an arc along the sheet discharge direction. The protruding member 13 is located below the sheet discharge port 2. More specifically, the protruding member 13 is located below the processing tray 8 and below the discharge path of the sheets discharged from the discharge roller pair 73 along the processing tray 8. Multiple protruding members 13 (two in this case) are arranged at predetermined intervals with the center of the loading tray 11 in between in the sheet width direction. The protruding member 13 and the paddle member 15 are aligned in the sheet width direction.

[0053] The support holder 20 is fixed to the post-processing housing 50 (not shown). As shown in Figure 4, one support holder 20 is provided at a position that overlaps with each protruding member 13 in the sheet width direction.

[0054] Figure 5 is a side view of the support holder 20, viewed from the axial direction (along the rotation axis 32, which will be described later). Figure 6 is a side view of the structure of the sheet discharge device 10 near the protruding member 13, viewed from the downstream side in the sheet discharge direction (lower left side in Figure 4). Note that the first set collar 28 and the pinion gear 27 are omitted from Figure 6. As shown in Figures 4 to 6, the support holder 20 has side wall portions 21a and 21b, a guide rail 22, a cover rib 23, and a positioning projection 24.

[0055] The side wall portions 21a and 21b are plate-like portions formed at both ends of the support holder 20 in the axial direction. The side wall portions 21a and 21b face each other in the axial direction. Collar support holes 25 that penetrate in the axial direction are formed in the side wall portions 21a and 21b. The protruding member 13 is positioned between the side wall portions 21a and 21b in the axial direction.

[0056] The guide rail 22 has a rib shape that protrudes from the side wall portions 21a and 21b toward the inside of the support holder 20 in the axial direction. The guide rail 22 extends parallel to the direction of movement of the protruding member 13, following the arc shape of the protruding member 13. The cover rib 23 is provided so as to face the guide rail 22 in a direction perpendicular to the axial direction and the sheet discharge direction. A gap is formed between the cover rib 23 and the guide rail 22.

[0057] The protruding member 13 is positioned between the guide rail 22 and the cover rib 23. The protruding member 13 is supported by the support holder 20 so as to be able to reciprocate between a protruding position P1 and a retracted position P2 along the guide rail 22. Hereinafter, the direction in which the protruding member 13 moves will be simply referred to as the "direction of movement".

[0058] The protruding position P1 is the position where the protruding member 13 protrudes from the support holder 20 in the direction of movement (the position shown by the dashed line in Figures 3 and 6). The retracted position P2 is the position where the protruding member 13 retracts inside the support holder 20 in the direction of movement (the position shown by the solid line in Figure 3, and the dashed and solid lines in Figure 5). Of the directions of movement, the direction in which the protruding member 13 moves toward the protruding position P1 is called the "protruding direction," and the direction in which the protruding member 13 moves toward the retracted position P2 is called the "retracted direction."

[0059] As shown in Figure 5, the positioning projection 24 is connected to the lower end of the guide rail 22 (the downstream end in the retraction direction). The positioning projection 24 protrudes from the guide rail 22 so as to be perpendicular to the guide rail 22. The positioning projection 24 faces the protruding member 13 in the direction of movement.

[0060] When the protruding member 13 moves in the retraction direction and reaches the retraction position P2, it comes into contact with the positioning projection 24. In this state, the protruding member 13 is restricted from moving in the retraction direction by the positioning projection 24 and is positioned at the reference position P2', which is the furthest from the protruding position P1 within the retraction position P2. When the protruding member 13 is at the reference position P2', the tip of the protruding member 13 (the downstream end in the protruding direction) is located inside (upstream in the protruding direction) the tip of the support holder 20.

[0061] The moving mechanism 26 moves the protruding member 13 between the protruding position P1 and the retracted position P2. As shown in Figures 4 to 6, the moving mechanism 26 is composed of the support holder 20, the rotating shaft 32, the fixing member 45, the pinion gear 27, the rack gear 31, and the drive device 131.

[0062] The rotating shaft 32 extends parallel to the drive roller shaft 731a. The rotating shaft 32 is inserted into the collar support holes 25 of each support holder 20. The rotating shaft 32 faces the protruding member 13 in the radial direction. A pinion gear 27 is externally mounted on the rotating shaft 32.

[0063] Figure 7 is an enlarged perspective view showing the structure around the protruding member 13. Figure 8 is an enlarged plan view showing the structure around the protruding member 13 when the pinion gear 27 is in the drive position P3. Figure 9 is an enlarged perspective view showing the structure around the tip of the protruding member 13.

[0064] As shown in Figures 7 and 8, the pinion gear 27 is a spur gear having multiple gear teeth on its outer circumference. The rotating shaft 32 passes through the radial center of the pinion gear 27. One pinion gear 27 is positioned along the longitudinal direction of the rotating shaft 32, overlapping each of the protruding members 13 (see Figure 4). The pinion gear 27 is located between a pair of side walls 21a and 21b of the support holder 20 in the axial direction. The pinion gear 27 faces the protruding members 13 in the radial direction.

[0065] The rotating shaft 32 is inserted through a through hole (not shown) formed in the radial center of the pinion gear 27 with a small gap between them. That is, the pinion gear 27 is supported so as to be able to reciprocate (slide) in the axial direction relative to the rotating shaft 32. The pinion gear 27 has a gear-side connecting portion 33 that protrudes toward one direction in the axial direction.

[0066] The fixing member 45 holds the pinion gear 27 in the axial direction. The fixing member 45 has a first set collar 28 (connecting member) and a second set collar 29 (positioning member).

[0067] A first set collar 28 is positioned on one axial side (side wall 21b side) of the pinion gear 27. The first set collar 28 is inserted into a collar support hole 25 in the side wall 21b with a small gap in between. The first set collar 28 is not fixed to the support holder 20. A through hole (not shown) is formed in the radial center of the first set collar 28, and the rotating shaft 32 is inserted into this through hole. The first set collar 28 is fixed to the rotating shaft 32. When the rotating shaft 32 rotates, the first set collar 28 rotates integrally with the rotating shaft 32 and slides against the collar support hole 25.

[0068] A retaining ring 34a is positioned on one side of the first set collar 28 in the axial direction (opposite the side wall portion 21b, the left side in Figure 8). The retaining ring 34a is a metal E-ring. The retaining ring 34a is detachably mounted on the rotating shaft 32. The retaining ring 34a is in contact with the first set collar 28 in the axial direction. The first set collar 28 is positioned between the side wall portion 21b and the retaining ring 34a in the axial direction, and its axial movement is restricted by contact with the side wall portion 21b and the retaining ring 34a.

[0069] The first set collar 28 has a collar-side connecting portion 35 that protrudes from the first set collar 28 toward the other side in the axial direction (the side of the side wall portion 21b, the right side in Figure 8). The collar-side connecting portion 35 has an engaging recess 36 that is recessed toward the radially inward direction of the rotation axis 32 (see Figure 6).

[0070] The engaging recess 36 is formed so that the gear-side connecting portion 33 can be inserted into it. With the gear-side connecting portion 33 inserted into the engaging recess 36, the engaging recess 36 and the gear-side connecting portion 33 face each other with respect to the circumferential direction of the rotating shaft 32. When the first set collar 28 rotates in this state, the engaging recess 36 comes into contact with the gear-side connecting portion 33, and the pinion gear 27 rotates together with the first set collar 28.

[0071] In the axial direction, a second set collar 29 is positioned on the other side of the pinion gear 27 (opposite the first set collar 28, which has the pinion gear 27 in between, on the right side in Figure 8). The second set collar 29 is inserted into a collar support hole 25 in the side wall portion 21a. A through hole (not shown) is formed in the radial center of the second set collar 29, and the rotating shaft 32 is inserted into this through hole with a small gap. The second set collar 29 is prevented from rotating relative to the collar support hole 25. When the rotating shaft 32 rotates, the outer circumferential surface of the rotating shaft 32 slides against the inner circumferential surface of the second set collar 29.

[0072] As shown in Figure 8, a retaining ring 34b is positioned on the other side of the second set collar 29 in the axial direction (opposite to the first set collar 28, on the right side in Figure 8). The retaining ring 34b is a metal E-ring. The retaining ring 34b is detachably mounted on the rotating shaft 32. With the retaining ring 34b mounted on the rotating shaft 32, the second set collar 29 is in contact with the retaining ring 34b on the other side in the axial direction, restricting its movement to the other side in the axial direction.

[0073] In this state, the pinion gear 27 and the second set collar 29 are facing each other in the axial direction. In this state, the pinion gear 27 is in contact with the second set collar 29, and its movement to the other side in the axial direction (opposite side of the first set collar 28, to the right in Figure 8) is restricted.

[0074] Figure 9 is a plan view showing the state after removing the retaining ring 34b and moving the pinion gear 27 to the separated position P4 from the state shown in Figure 8. As shown in Figure 9, with the retaining ring 34b removed from the rotating shaft 32, the second set collar 29 can be removed along the rotating shaft 32 to the outside of the collar support hole 25.

[0075] Figure 10 is a magnified perspective view showing the structure around the tip of the rack gear 31. As shown in Figures 8 to 10, the rack gear 31 is a rack gear consisting of multiple gear teeth arranged along the direction of movement of the protruding member 13. The rack gear 31 is formed on the surface 37 of the protruding member 13 facing the pinion gear 27.

[0076] The rack gear 31 is engageable with the pinion gear 27. The pinion gear 27 and the rack gear 31, when engaged with each other, constitute a rack-and-pinion gear mechanism with the pinion gear 27 as the pinion gear. That is, when the pinion gear 27 rotates while the pinion gear 27 and the rack gear 31 are engaged with each other, the rack gear 31 moves along the direction of rotation of the pinion gear 27. As a result, the protruding member 13 moves.

[0077] A narrow region 40 is formed at the downstream end of the rack gear 31 in the direction of protrusion. The narrow region 40 includes a notch 38 and a narrow gear 39. The notch 38 cuts out the rack gear 31 from the other side (the second set collar 29 side, the right side in Figures 8 and 9) to the one side (the first set collar 28 side, the left side in Figures 8 and 9) in the axial direction.

[0078] The narrow gear 39 is the remaining portion of the rack gear 31 that has been cut out by the notch 38. The narrow gear 39 is adjacent to one side of the notch 38 in the axial direction. The pinion gear 27 engages with the rack gear 31 at the narrow gear 39 and separates from the rack gear 31 at the notch 38.

[0079] Returning to Figure 8, with the retaining ring 34a installed and the axial movement of the second set collar 29 restricted, the pinion gear 27 is positioned at the drive position P3. The drive position P3 is the axial position of the pinion gear 27 where it engages with the rack gear 31 (position of the pinion gear 27 in Figure 8). When the pinion gear 27 is in the drive position P3 and is in a position where it overlaps with the notch 38 in the direction of movement, the pinion gear 27 is engaged with the narrow gear 39.

[0080] As shown in Figure 9, when the retaining ring 34a is removed and the restriction on the movement of the second set collar 29 and the pinion gear 27 is released, the pinion gear 27 becomes capable of reciprocating in the axial direction between the drive position P3 and the separation position P4. The separation position P4 is the position of the pinion gear 27 located on the other side of the drive position P3 in the axial direction (position of the pinion gear 27 in Figure 9).

[0081] The meshing position P3' is defined as the position where the pinion gear 27 overlaps with the narrow region 40 in the direction of movement and with the narrow gear 39 in the axial direction. When the pinion gear 27 is in the meshing position P3', the pinion gear 27 engages with the rack gear 31 via the narrow gear 39.

[0082] The pinion gear 27 is in a release position P4' when it is in a position P4 separated from the axial direction and overlapping with the narrow region 40 in the direction of movement. When the pinion gear 27 is in the release position P4', the engagement between the pinion gear 27 and the narrow gear 39, i.e., the rack gear 31, is released. When the pinion gear 27 is in the separated position P4 and is located on the retraction side of the narrow region 40 in the direction of movement, the pinion gear 27 is engaged with the rack gear 31.

[0083] Regardless of whether the pinion gear 27 is in the drive position P3 or the separated position P4, the gear-side connecting portion 33 is inserted into the engaging recess 36, preventing the pinion gear 27 from rotating relative to the first set collar 28.

[0084] Returning to Figure 4, the drive unit 131 consists of a drive motor 807, a drive transmission pulley 806, and a drive transmission belt 805. The drive motor 807 has a main body 808, a motor shaft 809 protruding from the main body 808, and a motor gear 810 fixed to the end of the motor shaft 809, and outputs rotational driving force via the motor shaft 809 and the motor gear 810. The rotational control of the drive motor 807 (rotation angle, rotation speed, etc.) is performed by the post-processing control unit 100.

[0085] The drive transmission pulley 806 is a toothed pulley fixed to the rotating shaft 32 and rotates integrally with the rotating shaft 32. The drive transmission belt 805 is an endless toothed belt wrapped around the motor gear 810 and the drive transmission pulley 806.

[0086] When rotational driving force is output from the drive motor 807, the motor gear 810 rotates, and the rotational driving force is transmitted to the rotating shaft 32 via the drive transmission belt 805 and drive transmission pulley 806, causing the rotating shaft 32 to rotate. As the rotating shaft 32 rotates, the two protruding members 13 move simultaneously between the protruding position P1 and the retracted position P2 by the moving mechanism 26 as described above.

[0087] By adopting the configuration of the above embodiment, the pinion gear 27 and the rack gear 31 can be separated and disengaged from each other while the pinion gear 27 is in the released position P4'. In this state, even if one of the protruding members 13 is shifted in the direction of movement, the rotation shaft 32 does not rotate and the other protruding member 13 does not move because the pinion gear 27 is separated from the rack gear 31. Therefore, in this state, the position of the protruding member 13 in the direction of movement, i.e., the amount of protrusion, can be adjusted.

[0088] Specifically, after moving the protruding member 13 until the pinion gear 27 overlaps with the notch 38 in the direction of movement, moving the pinion gear 27 to the separated position P4 (release position P4') causes the pinion gear 27 to face the notch 38 and separate from the rack gear 31. As a result, each protruding member 13 becomes movable in the direction in which the rack gear 31 is not formed (towards the retracted position P2). Then, after adjusting the protrusion amount of each protruding member 13, moving the pinion gear 27 back to the drive position P3 allows for precise alignment of the protrusion amounts of each protruding member 13. Furthermore, since the pinion gear 27 can move between the drive position P3 and the release position P4' without disassembling the movement mechanism 26, the complexity of adjusting the protrusion amount can be suppressed. Therefore, a sheet discharge device 10 is provided that allows for easy adjustment of the protrusion amount of the protruding members 13 with a simple configuration.

[0089] Furthermore, as described above, by removing the retaining ring 34b, the second set collar 29 and the pinion gear 27 can be moved between the drive position P3 and the separated position P4, and the positioning and release of the pinion gear 27 can be switched with a simple configuration.

[0090] Furthermore, the removal of the retaining ring 34b and the second set collar 29, the movement of the pinion gear 27 between the drive position P3 and the separated position P4, and the adjustment of the protrusion amount of the protruding member 13 can all be performed manually by the user. Therefore, the protrusion amount of each protruding member 13 can be adjusted even when the power to the seat post-processing device is turned off.

[0091] Furthermore, as described above, the notch 38 is formed at the downstream end of the rack gear 31 with respect to the protruding direction. Therefore, when the protruding member 13 is in the retracted position P2, the pinion gear 27 and the notch 38 overlap in the direction of movement. This allows each protruding member 13 to be reliably positioned in the retracted position P2 by bringing it into contact with the positioning projection 24. Consequently, the amount of protrusion of each protruding member 13 becomes easy to adjust.

[0092] Furthermore, the present invention is not limited to the embodiments described above, and various modifications are possible without departing from the spirit of the invention. For example, in the above embodiments, the image forming apparatus 200 of the image forming system S is a multifunction device for monochrome printing, but it is not limited to this. The image forming apparatus 200 may be, for example, a monochrome copier, a monochrome printer, or an image forming apparatus for color printing such as a color copier or a color printer.

[0093] Furthermore, as shown in Figure 11, a configuration can be adopted in which the narrow region 40 is formed over the entire area of ​​the rack gear 31 in the direction of movement. In other words, the notch 38 is formed over the entire area of ​​the rack gear 31 in the direction of movement. In this case, with the pinion gear 27 positioned at the drive position P3, the rack gear 31 engages with more than half of the pinion gear 27 in the axial direction. In this way, regardless of the position of the protruding member 13 in the direction of movement, moving it to the other side in the axial direction (opposite side of the first set collar 28) will cause the pinion gear 27 to overlap with the notch 38. Therefore, the pinion gear 27 and the rack gear 31 can be easily separated.

[0094] Furthermore, the post-processing control unit 100 can execute a positioning mode. When the positioning mode is executed, the motor gear 810 is rotated by a predetermined rotational angle, and the rotation is stopped when the notch 38 reaches a position where it overlaps with the pinion gear 27 in the direction of movement. The execution of the positioning mode can be input from an input unit (not shown), such as a touch panel, provided on the main control unit 213. Alternatively, it may be configured to be input from a higher-level device (such as a personal computer) connected to the image forming system S.

[0095] In this state, the user can visually confirm the misalignment of each protruding member 13 in the direction of movement. Furthermore, the user can disengage the pinion gear 27 and the rack gear 31 after the alignment mode has been executed. [Industrial applicability]

[0096] The present invention can be used in a sheet post-processing device that is positioned downstream of an image forming apparatus and performs predetermined post-processing on sheets discharged from the image forming apparatus. The present invention makes it possible to match the protrusion amounts of each protruding member. Furthermore, it can be installed not only in a sheet post-processing device but also at the sheet discharge port of an image forming apparatus. [Explanation of symbols]

[0097] 5 Sheet Post-processing Device 10 Sheet Discharge Device 11 Loading tray 13. Protruding member 20 Support holder (holding member) 24 Positioning projection 26 Moving mechanism 27 Pinion Gear 28. First set of collars (connecting parts) 29. Second set collar (positioning member) 31 Rack Gear 32 Rotation axis 38 Notch 40 Narrow area 73 Discharge rollers 731 Second drive roller (discharge roller) 731a Drive roller shaft 200 Image forming apparatus P Sheet P1 protrusion position P2 Evacuation position P2´ Reference position P3 Drive position P3´ Meshing position P4 Separate position P4´ release position S Image Forming System

Claims

1. A pair of discharge rollers that discharge the sheet from the discharge port, A loading tray is provided, which is positioned downstream of the pair of discharge rollers with respect to the sheet discharge direction, and on which the sheets discharged by the pair of discharge rollers are loaded. Multiple protruding members are supported so as to be able to reciprocate between a protruding position that extends from the discharge port above the loading tray and in which the leading edge of the sheet discharged by the pair of discharge rollers contacts the upper surface and is guided in the discharge direction, and a retracted position that is retracted from above the loading tray. A moving mechanism for moving each of the aforementioned protruding members between the protruding position and the retracted position, In a sheet discharge device equipped with, The aforementioned moving mechanism is A rotatably supported rotating shaft extending in a width direction perpendicular to the discharge direction, A plurality of holding members connected to the rotating shaft, each of the protruding members being movably held, A plurality of rack and pinion mechanisms comprising: a plurality of pinion gears supported on the rotation shaft at positions overlapping with each of the protruding members in the width direction; and a plurality of rack gears consisting of a plurality of gear teeth formed on the surface of each of the protruding members facing the respective pinion gears and arranged along the direction of movement of the protruding member; It has, At least a portion of the movement direction of each rack gear is provided with a narrow region including a narrow gear formed by cutting out a portion of the gear teeth in the axial direction, and a notched portion. Each pinion gear is slidable between a meshing position in the narrow region where it engages with the narrow gear, and a disengagement position where it faces the notch and disengages from the narrow gear. A sheet discharge device characterized in that each of the protruding members is movable relative to the pinion gear in the direction of movement when the pinion gear is in the release position.

2. Each of the holding members is A positioning member for positioning the pinion gear at the meshing position, A connecting member that engages with the rotating shaft and the pinion gear to restrict the rotation of the pinion gear relative to the rotating shaft, The sheet discharge device according to claim 1, characterized by having the following features.

3. The sheet discharge device according to claim 1, characterized in that the narrow region is formed in a position opposite to the pinion gear with respect to the direction of movement when the protruding member is in the retracted position.

4. The sheet discharge device according to claim 3, characterized in that the holding member has a positioning projection that contacts the protruding member and positions the protruding member at a reference position furthest from the protruding position in the retracted position with respect to the direction of movement.

5. The sheet discharge device according to any one of claims 1 to 4, characterized in that the narrow region is formed over the entire area of ​​the rack gear with respect to the direction of movement.

6. A post-processing mechanism for performing predetermined post-processing on the aforementioned sheet, A sheet discharge device according to any one of claims 1 to 4, comprising a pair of discharge rollers positioned downstream of the post-processing mechanism with respect to the discharge direction, wherein the sheet that has been post-processed by the post-processing mechanism is loaded onto the loading tray by the pair of discharge rollers, A sheet post-processing device equipped with the following:

7. A sheet post-processing device according to claim 6, An image forming apparatus connected to the sheet post-processing apparatus, which forms an image on the sheet and transports the image-formed sheet to the sheet post-processing apparatus, An image forming system comprising the following features.

Images