Sheet processing apparatus and image forming apparatus

Abstract

To provide a compact sheet processing device equipped with sheet binding means.SOLUTION: A sheet processing device B comprises: first binding means 51 movable along the end edge of a sheet on a processing tray 24; and second binding means 52 disposed near the corner of the sheet in a sheet width direction on the processing tray. A first sheet end regulation member 37 for regulating the end edge of the sheet on the processing tray in a carrying-in direction is movable between a first position far from and a second position near the second binding means in the sheet width direction between the first binding means and the second binding means. The first binding means is configured to be able to execute binding of the sheet end edge in a state where the first sheet end regulation member is at the second position.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a sheet processing apparatus that performs binding processing on a bundle of sheets, and an image forming apparatus that includes such a sheet processing apparatus. [Background technology]

[0002] 2. Description of the Related Art Some conventional image forming apparatuses, such as copying machines, laser beam printers, facsimiles, and multifunction machines thereof, are equipped with a sheet processing apparatus that performs sheet processing such as binding on sheets on which images have been formed.

[0003] Image forming devices are known that are equipped with both a staple binding means that uses metal staples such as staples as a binding means for binding multiple sheets, and a stapleless binding means that processes the sheets themselves to bind them without using metal staples (see, for example, Patent Document 1).

[0004] Furthermore, the image forming apparatus described in Patent Document 1 has a configuration in which a sheet processing apparatus that performs post-processing on sheets on which images have been formed is disposed in the space within the body defined between the image forming unit and the image reading unit above it. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-61964 Summary of the Invention [Problem to be solved by the invention]

[0006] The dimensions and volume of the internal space of an image forming apparatus are usually limited in order to make the entire apparatus compact. In particular, when stapling is performed near a corner on the upstream side in the sheet conveyance direction and on the far side, there is a risk that the staple binding means and the stapleless binding means will interfere with each other in the narrow space.

[0007] The present invention has been made in consideration of the above-mentioned problems of the conventional art, and has an object to configure a sheet processing apparatus that performs both staple binding and stapleless binding processes in a more compact manner.

[0008] Another object of the present invention is to provide an image forming apparatus having a compact sheet processing device capable of both staple binding and stapleless binding in the internal space of the body, thereby making the entire apparatus compact. [Means for solving the problem]

[0009] The sheet processing apparatus of the present invention comprises: A sheet processing apparatus that performs binding processing on a sheet bundle, a tray for stacking the conveyed sheets one by one to form a sheet bundle; a plurality of abutting means arranged in front and rear directions of the sheet processing apparatus, against which the edge of the sheet on the tray abuts; a shift unit that shifts the sheet that has been abutted against the abutting means in the front-to-rear direction; a stapler configured to be able to staple a corner portion of the sheet stack abutted against the abutting means and on the rear side in the front-rear direction of the sheet stack; a stapleless binding unit that is provided on the rear side of the abutting means and is configured to be able to perform stapleless binding on a corner portion of the sheet bundle that is abutted against the abutting means and on the rear side, The abutting means is configured such that an abutting member disposed at the innermost side in the front-rear direction is movable in the front-rear direction on the front side of the stapleless binding unit in the front-rear direction, When the stapler is used to staple the corner portion of a sheet bundle consisting of predetermined sheets, the abutting member is moved to the rear side and the shift unit shifts the sheets to the front side, so that the stapler performs the staple processing on the corner portion of the sheet bundle on the front side of the abutting member that has moved to the rear side. It is characterized by:

[0010] In yet another aspect of the present invention, the image forming apparatus of the present invention comprises: Sea To image of an image forming unit that forms an image; an image reading unit disposed above the image forming unit; an internal space defined between the image forming unit and the image reading unit; The trunk Inside sky In between Equipped A sheet bundle including sheets on which images have been formed by the image forming unit is bound. Sheet processing unit 、 Equipped with The sheet processing unit is characterized by comprising the sheet processing apparatus of the present invention described above. [Effects of the Invention]

[0011] According to the sheet processing apparatus of the present invention, the entire apparatus can be configured compactly, and the corners of the sheets can be bound using either the first binding means or the second binding means. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a diagram showing the overall configuration of an image forming apparatus to which the present invention is applied; [Figure 2] 1 is a diagram showing the overall configuration of a sheet processing apparatus according to the present invention; [Figure 3] FIG. 3 is a plan view showing a main part of the sheet processing apparatus shown in FIG. 2. [Figure 4] 10A and 10B are perspective views showing the configuration and movement of a first sheet end regulating member. [Figure 5] FIG. 4 is a perspective view showing the positional relationship between a first sheet end regulating member and a stapler. [Figure 6] FIG. 10 is a perspective view of the first sheet end regulating member as viewed from the upstream side in the conveying direction. [Figure 7] 1A to 1C are explanatory diagrams showing the sheet conveying operation of the sheet processing apparatus in order. [Figure 8] 8(a) to 8(c) are explanatory diagrams showing the sheet conveying operation of the sheet processing apparatus in sequence following FIG. 7. [Figure 9] 1A and 1B are explanatory diagrams showing the sheet binding process operation in sequence in the first embodiment. [Figure 10] 10A and 10B are explanatory diagrams showing the binding process operation in sequence following FIG. 9. [Figure 11] 11A and 11B are explanatory diagrams showing the binding process operation in sequence following FIG. 10 . [Figure 12] 12A and 12B are explanatory diagrams showing the binding process operation in sequence following FIG. 11 . [Figure 13] 10A and 10B are explanatory diagrams showing the sheet binding process operation in sequence in the second embodiment. [Figure 14] 14A and 14B are explanatory diagrams showing the binding process operation in sequence following FIG. 13. [Figure 15] 15A and 15B are explanatory diagrams showing the binding process operation in sequence following FIG. 14. [Figure 16] FIG. 16 is an explanatory diagram showing the binding processing operation following FIG. 15 . [Figure 17] 11A and 11B are explanatory diagrams showing the sheet binding process operation in sequence in the third embodiment. [Figure 18] 18A and 18B are explanatory diagrams showing the binding process operation in sequence following FIG. 17. [Figure 19] 19(a) and 19(b) are explanatory diagrams showing the binding processing operation in sequence following FIG. 18. [Figure 20] 19A and 19B are explanatory diagrams showing the binding process operation in sequence following FIG. 19. [Figure 21] 10A and 10B are explanatory diagrams showing the sheet binding process operation in sequence in the fourth embodiment. [Figure 22] 22(a) and 22(b) are explanatory diagrams showing the binding processing operation in sequence following FIG. 21. [Figure 23] 23(a) and 23(b) are explanatory diagrams showing the binding processing operation in sequence following FIG. 22. [Figure 24] 24(a) and 24(b) are explanatory diagrams showing the binding processing operation in sequence following FIG. 23. [Figure 25] 25(a) and 25(b) are explanatory diagrams showing the binding processing operation following FIG. 24. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0014] [Image forming device] 1 shows the overall configuration of an image forming apparatus to which the present invention is applied, as seen from the front side. In this specification, the front side of the image forming apparatus in FIG. 1 will be referred to as the front side of the apparatus, and the back side will be referred to as the rear side of the apparatus.

[0015] The image forming apparatus in Fig. 1 is composed of an image forming unit A, a sheet processing device B, an image reading unit C, and an automatic document feeding unit D. The sheet processing device B functions as a post-processing device for sheets on which images are formed by the image forming unit A. The image forming apparatus of this embodiment is a so-called internal paper discharge type in which a large, U-shaped paper discharge space (internal space) is defined between the image forming unit A and the image reading unit C in Fig. 1, and the sheet processing device B is disposed within the internal space.

[0016] Image forming unit A forms an image on a sheet based on image data of the original image read by image reading unit C, and transports the image-formed sheet to sheet processing device B. As will be described later, sheet processing device B collates and accumulates the sheets transported from image forming unit A, binds them, and then stores them in a stacking tray. In this specification, the term "sheet transport direction" refers to the direction in which a sheet is transported from image forming unit A to sheet processing device B, and the term "sheet width direction" refers to a direction intersecting the sheet transport direction, and particularly in this embodiment, a direction perpendicular to the sheet transport direction.

[0017] [Image formation unit] 1, the image forming unit A is made up of a paper feed section 1, an image forming section 2, a paper discharge section 3, and a signal processing section (not shown), all of which are housed in a device housing 4. The paper feed section 1 is made up of cassettes 5 (in the illustrated embodiment, multiple cassettes 5a, 5b, and 5c) that store sheets. Each of the cassettes 5a to 5c has a built-in paper feed roller 6 that feeds out sheets, and a separation means (not shown) such as a separation claw or separation roller that separates sheets one by one, and is configured to be able to store sheets of different sizes.

[0018] The paper feed unit 1 has a paper feed path 7 that feeds sheets from cassettes 5 to the image forming unit 2. The paper feed unit 1 feeds sheets from cassettes 5a, 5b, and 5c that correspond to the size selected by the control unit, and feeds them to the downstream image forming unit 2 via the paper feed path 7. At the end of the paper feed path 7, a pair of registration rollers 8 is provided that aligns the leading edge of the sheets fed from each cassette 5 and keeps the sheets waiting until they are fed in accordance with the image formation timing of the image forming unit 2.

[0019] The image forming unit 2 can employ various image forming mechanisms for forming an image on a sheet, such as an electrostatic printing mechanism, an inkjet image forming method, an offset printing method, a silk printing method, etc. The image forming unit 2 shown in the figure is of a type that forms an image on a sheet by a known electrostatic printing mechanism.

[0020] A plurality of drums 9a-9d (four drums 9a-9d corresponding to four color components in the illustrated embodiment) are arranged within the device housing 4. Each drum 9a, 9b, 9c, and 9d is composed of a photoconductor, and is provided with a light emitter (such as a laser head) 10 and a developing device 11. A latent image (electrostatic image) is formed on each drum 9a-9d by the light emitter 10, and toner ink is applied by the developing device 11. The ink images applied to each drum are transferred to a transfer belt 12 for each color component and synthesized. The transferred image formed on the transfer belt 12 is transferred by a charger 13 onto a sheet fed from a paper feed unit 1, fixed by a fixing device (heating roller) 14, and then sent to a paper discharge unit 3.

[0021] The paper discharge unit 3 is provided with a paper discharge outlet 16 that conveys the sheet to a paper discharge space (internal space) 15, and a paper discharge path 17 that guides the sheet from the image forming unit 2 to the paper discharge outlet 16. Furthermore, a duplex path 18 is connected to the paper discharge unit 3 in order to turn over the sheet with an image formed on its front side and feed it again to the image forming unit 2.

[0022] The duplex path 18 inverts a sheet on which an image has been formed on the front side by the image forming unit 2 and re-sends it to the image forming unit 2. A sheet on which an image has been formed on the back side by the image forming unit 2 is discharged from the paper discharge outlet 16. For this reason, the duplex path 18 is equipped with a switchback path that reverses the conveying direction of the sheet sent from the image forming unit 2 and returns it, and a U-turn path 18a that inverts the returned sheet.

[0023] [Image reading unit] The image reading unit C includes a platen 19a made of transparent glass and a reading carriage 19b that moves back and forth along the platen 19a. The reading carriage 19b is made up of a light source lamp, an optical mirror that reflects light from the document, and a photoelectric conversion element. The photoelectric conversion element is made up of line sensors arranged in the document width direction (main scanning direction) on the platen.

[0024] The document image on the platen 19a is read by scanning the reading carriage 19b while it moves in the sub-scanning direction perpendicular to the main scanning direction. Also, the reading carriage 19b can read the document image traveling at a predetermined speed on the platen 19a while remaining stationary.

[0025] [Automatic document feeder unit] The automatic document feeder unit D is disposed above the image reading surface of the platen 19a and includes a feeder mechanism that feeds document sheets set on a paper feed tray one by one to the platen 19a, reads the images on the document sheets using the reading carriage 19b, and then stores the document sheets in an output tray. The feeder mechanism is configured to run the document sheets from the paper feed tray over the image reading surface of the platen 19a at a predetermined speed.

[0026] [Sheet processing device] 2, the sheet processing device B includes a device housing 21, a transport path 22 provided within the device housing for transporting sheets in the sheet transport direction, a processing tray 24 disposed downstream of a sheet discharge outlet 23 on the transport path, and a stacking tray 25 disposed further downstream thereof. The processing tray 24 is provided with a sheet carry-in mechanism 26 for carrying sheets discharged from the sheet discharge outlet 23 to the rear side of the processing tray 24, i.e., the upstream side in the sheet transport direction, a sheet alignment mechanism 27 for accumulating and positioning a plurality of sheets carried in on the processing tray 24 in a bundle, and a binding mechanism 28 for binding the aligned sheet bundle.

[0027] The transport path 22 is provided with a feeder mechanism in which pairs of transport rollers, such as a pair of carry-in rollers 31 and a pair of discharge rollers 32, are arranged at a predetermined interval to transport the sheet received from the image forming unit B from the carry-in entrance 30 to the discharge exit 23. It is advantageous if the transport path 22 is provided with a sheet sensor for detecting the leading and / or trailing edge of the sheet being transported.

[0028] As shown in the figure, the processing tray 24 is disposed at a predetermined step below the sheet discharge port 23 of the conveyance path 22. The processing tray 24 has a paper mounting surface 24a for supporting at least a portion of the sheets so that the sheets discharged from the sheet discharge port 23 can be stacked one above the other and accumulated into a stack, i.e., a sheet bundle. A sheet edge regulating means 29 constituting a sheet alignment mechanism 27 is disposed at the upstream end of the processing tray 24 in the sheet conveyance direction.

[0029] In this embodiment, a so-called bridge support structure is employed in which the front (downstream) portion of the sheet along the sheet conveying direction is supported by the stacking tray 25, and the opposite rear (upstream) portion is supported by the processing tray 24. As a result, the sheet processing device B reduces the overall tray size of the processing tray 24 in the sheet conveying direction, i.e., in the direction in which the sheet is carried into (or carried out of) the processing tray 24.

[0030] The sheet carry-in mechanism 26 is equipped with a transport roller device 47 for smoothly transporting sheets discharged from the sheet discharge port 23 via the step toward the back of the processing tray 24 in the correct orientation, i.e., with the left and right side edges of the sheet in the sheet width direction straight with respect to the carry-in direction. The transport roller device 47 has a roller pair consisting of an upper transport roller 48 and a lower driven roller 49, with the processing tray 24 sandwiched between them. The transport roller 48 is rotatably supported at the tip of a lift bracket 50 that is swingably supported above the processing tray 24, and the driven roller 49 is rotatably provided at a fixed position immediately below the processing tray.

[0031] The sheet carry-in mechanism 26 further includes a take-in rotating body 33 for guiding the leading edge of the sheet in the carry-in direction toward the rear side to deal with curls and skews that may occur when the sheet is transported to the rear on the processing tray 24. The take-in rotating body 33 has a take-in belt 34 made of a ring-shaped (or short cylindrical) belt member that is arranged above the processing tray 24 and in front of the sheet end regulating means 29 in the carry-in direction.

[0032] The take-in belt 34 is provided so as to be movable up and down by a lifting mechanism (not shown) toward the upper surfaces of the sheets on the paper loading surface 24a. The take-in belt 34 descends in synchronization with the timing at which the sheets carried into the processing tray 24 are sent in the carry-in direction by the transport roller device 47, engages with the upper surface of the uppermost sheet on the paper loading surface 24a, and rotates in a direction that sends the sheet in the carry-in direction.

[0033] The sheet alignment mechanism 27 is composed of the above-mentioned sheet edge regulating means 29 and side alignment means 40. As shown in Fig. 3, the sheet edge regulating means 29 includes a plurality of (three in the illustrated embodiment) sheet edge regulating members 36-38 arranged along the sheet width direction on the edge of the processing tray 24 on the rear side in the carry-in direction (upstream side in the sheet conveyance direction). The main sheet edge regulating member 36 is fixedly provided at the center position in the sheet width direction, which is the center reference of the processing tray 24. A first sheet edge regulating member 37 is arranged on the rear side of the device (right side in the figure) of the main sheet edge regulating member 36 in the sheet width direction, and a second sheet edge regulating member 38 is arranged on the front side of the device (left side in the figure).

[0034] A first binding device 51 and a second binding device 52 constituting the binding mechanism 28 are disposed immediately outside the rear edge of the processing tray 24 in the feed direction. In this embodiment, the first binding device 51 is a staple binding device that performs staple binding, as described below, and the second binding device 52 is a stapleless binding device that performs stapleless binding. In FIG. 3, the first binding device 51 is disposed closer to the front of the device (left side in the drawing) than the second sheet edge regulating member 38 in the sheet width direction, and is provided to be movable along the rear edge of the processing tray 24 in the feed direction (i.e., the sheet edge regulated by the sheet edge regulating device 29). The second binding device 52 is fixed near a corner of the processing tray 24, closer to the rear of the device (right side in the drawing) than the first sheet edge regulating member 37 in the sheet width direction.

[0035] As shown in FIG. 2 for the second sheet edge regulating member 38, the sheet edge regulating members 36-38 have sheet edge regulating portions 41-43 made of channel-shaped members with a U-shaped cross section. The main sheet edge regulating member 36 has a pair of sheet edge regulating portions 41 on either side of the center reference in the sheet width direction. Inside the U-shaped sheet edge regulating portions 41-43, regulating surfaces 41a-43a are provided for abutting and stopping the leading edge of a sheet in the carry-in direction (the upstream edge in the sheet conveyance direction) being conveyed on the processing tray 24. The regulating surfaces 41a-43a are positioned to align their positions in the sheet carry-in direction, thereby regulating and / or aligning the positions of the sheets and sheet stacks on the processing tray 24 in the sheet carry-in direction.

[0036] 3, the first sheet edge regulating member 37 and the second sheet edge regulating member 38 are arranged symmetrically in the sheet width direction, sandwiching the main sheet edge regulating member 36. While the second sheet edge regulating member 38 is fixed in the position shown in the figure, the first sheet edge regulating member 37 is provided so as to be movable in the sheet width direction between a first position (reference position) set at the position shown in FIG. 3 and a second position set toward the rear of the device (right side in the figure). Note that the second sheet edge regulating member 38 can also be configured to be movable in the sheet width direction, as necessary.

[0037] 4(a) shows the first sheet edge regulating member 37 in the first position, and FIG. 4(b) shows the first sheet edge regulating member 37 in the second position. The first sheet edge regulating member 37 has a sheet edge regulating portion 42 integrally attached to the upper surface of a slide member 44, which is provided at a height not exceeding the paper loading surface 24a. The slide member 44 is supported by a slide shaft 45 in the sheet width direction, which is fixed to the device housing 21, so that the slide member 44 can slide freely along the slide shaft. This allows the first sheet edge regulating member 37 to move integrally with the slide member 44 in the sheet width direction along the slide shaft 45.

[0038] The slide shaft 45 extends in the sheet width direction along the rear edge of the processing tray 24 in the feed direction so as to cover at least the range over which the first sheet edge regulating member 37 can move from the first position toward the rear of the device. A stopper 46 that abuts and engages with the first sheet edge regulating member 37 or the slide member 44 is provided on the slide shaft 45 and / or the device housing 21 to prevent the first sheet edge regulating member 37 from moving beyond the first position toward the front of the device.

[0039] The slide member 44 is provided with a biasing means, which in this embodiment is a coil spring 53. One end 53a of the coil spring 53 is fixed to the slide member 44, and the other end 53b is fixed to the device housing 21, so that the coil spring 53 constantly biases the slide member 44 from the rear side of the device toward the first position. Therefore, after the first sheet end regulating member 37 moves toward the second position, the biasing force of the coil spring 53 can automatically and easily return the first position.

[0040] Furthermore, an engagement member 54 that engages with the first binding means 51 that moves from the front side of the device to the rear side of the device along the sheet width direction is integrally provided on the slide member 44. As shown in Fig. 4, the engagement member 54 is formed of a rigid rod-shaped member that protrudes downstream in the feed-in direction from the slide member 44. As shown in Fig. 5, the engagement member 54 is provided at a position where it can engage with an engagement portion 55 provided at the end of the first binding means 51 on the rear side of the device.

[0041] When the first binding means 51 moves toward the rear of the device in the sheet width direction beyond the second sheet edge regulating member 38 and the main sheet edge regulating member 36, the engagement portion 55 abuts against and presses the engagement member 54, causing the slide member 44 and the first sheet edge regulating member 37 to move integrally with the first binding means 51 toward the second position against the biasing force of the coil spring 53, and to stop when the first binding means 51 stops. When the first binding means 51 moves from its stopped position toward the front of the device, the slide member 44 and the first sheet edge regulating member 37 correspondingly move toward the first position due to the biasing force of the coil spring 53. When the first binding means 51 moves further toward the front of the device beyond the first position, the slide member 44 and the first sheet edge regulating member 37 are engaged by the stopper 46 and stopped at the first position.

[0042] The first sheet edge regulating member 37 is further provided with a guide portion 57 for sheets being carried into the processing tray 24. As shown in Fig. 6, the guide portion 57 has a guide surface 58 facing the sheet surface on the processing tray 24. The guide surface 58 has a flat portion 58a at the downstream end in the carrying-in direction that is substantially parallel to the paper loading surface 24a, and an inclined surface portion 58b that curves outward from the flat portion 58a toward the upstream side in the carrying-in direction.

[0043] The guide portion 57 is attached to the upper end portion of the sheet end regulating portion 42 on the upstream side in the carry-in direction via a parallel link mechanism 59. As shown in Figures 5 and 6, the parallel link mechanism 59 is a four-joint link structure in which two sets of parallel link arms 61a to 61d, 62a to 62d are rotatably connected by four common support shafts 63a to 63d so as to form a parallelogram, and is arranged symmetrically on the left and right sides, and the guide portion 57 is attached integrally to the support shaft 63a on the upstream side in the carry-in direction.

[0044] The parallel link mechanism 59 is provided with a spring 64 that constantly urges the guide portion 57 toward the paper loading surface 24a. As a result, a sheet carried onto the processing tray 24 is guided downstream in the carry-in direction by the guide surface 58 and is pressed toward the paper loading surface 24a by the flat portion 58a. Even if the height of the sheets on the processing tray 24 increases, the parallel link mechanism 59 lifts the guide portion 57 against the urging force of the spring 64, so that the sheets on the processing tray 24 are constantly pressed toward the paper loading surface 24a, preventing the uppermost sheet from floating above the sheets below.

[0045] The side alignment means 40 moves sheets and sheet stacks on the processing tray 24 in the sheet width direction and regulates and / or aligns the position of the sheets in the sheet width direction with their side edges. To this end, the side alignment means 40 has a pair of side alignment members 65, 66 arranged on either side of the center reference of the processing tray 24, as shown in FIG. 3. The side alignment members 65, 66 are flat plate-like members that extend vertically upward from the paper loading surface 24a of the processing tray 24 with their inner surfaces facing each other. The inner surfaces of the side alignment members 65, 66 engage with adjacent side edges in the sheet width direction of the sheets on the processing tray 24 and function as regulation surfaces 65a, 66a that regulate the position of the sheets in the sheet width direction.

[0046] Each side alignment member 65, 66 is integrally connected to a movable support portion (not shown) disposed on the rear side of the processing tray 24 via linear slits 67, 68 formed through the processing tray in the sheet width direction. For example, by individually rotating pinions meshing with racks formed on each movable support portion using a drive motor, the side alignment members 65, 66 can be moved independently toward or away from each other and stopped at desired widthwise positions. This allows the sheet widthwise positions of each side alignment member 65, 66 to be individually set according to the size of the sheets to be carried into the processing tray 24, and when moving a sheet stack in the sheet width direction, the position, movement amount, and offset amount from the center reference can be determined.

[0047] [First binding method] As described above, the first binding means 51 is a known stapling unit that uses metal staples to staple multiple locations on the edge of a sheet. As shown in Fig. 2, the first binding means 51 has an opening 71 that opens upstream in the feed direction toward the processing tray 24 in order to staple the downstream edge of the sheet on the processing tray 24 in the feed direction. The downstream edge of the sheet on the processing tray 24 in the feed direction protrudes from the paper mounting surface 24a downstream in the feed direction and enters the opening 71, where it is stapled.

[0048] The opening 71 penetrates the staple unit in the sheet width direction, and its dimensions are somewhat larger than the sheet end regulating portions 41-43 of the sheet end regulating members 36-38 when viewed in the sheet width direction, and it is positioned at a height position that includes the sheet end regulating portions 41-43 inside it. Therefore, when the first binding means 51 is moved in the sheet width direction, it can smoothly pass through the second sheet end regulating member 38 and the main sheet end regulating member 37.

[0049] In contrast, the first sheet end regulating member 37 is provided with the above-mentioned engagement member 54, so the first binding means 51 cannot move to the rear side of the device by climbing over the first sheet end regulating member 37. In other words, the first sheet end regulating member 37 is provided so as to be movable in the sheet width direction while being located between the first binding means 51 and the second binding means 52.

[0050] In a broad sense, the first binding means 51 includes a housing having an opening 71, a staple binding processing section held in the housing that performs a staple processing on a sheet stack, a drive motor that drives the staple binding processing section to perform the staple processing, and a slide rail and drive motor that move the housing in the sheet width direction. However, in the following description, the first binding means 51 refers to a device configuration in the narrow sense that includes the staple binding processing section and the housing and moves in the sheet width direction.

[0051] [Second binding method] The second binding means 52 is a crimp binding device that performs stapleless binding using a press bind mechanism that binds a sheet stack by crimping and deforming it between a pair of upper and lower crimping teeth with uneven surfaces, for example. As shown in Fig. 3, the second binding means 52 includes a crimp binding unit 72 with upper and lower crimping teeth provided at a position downstream in the sheet feed direction on the processing tray 24 and corresponding to a corner portion on the rear side of the device in the sheet width direction. The crimp binding unit 72 has an opening (not shown) for guiding the corner portion of the sheet on the processing tray 24 between the upper and lower crimping teeth.

[0052] [Sheet transport operation of sheet processing device] 2, 7, and 8, the conveying operation of a sheet and a sheet stack in the sheet processing device B will be described. The sheet S conveyed from the image forming unit A to the sheet processing device B is sent in the sheet conveying direction from the carry-in entrance 30 along the conveying path 22 by the conveying roller pair, and is discharged from the paper discharge outlet 23 onto the processing tray 24, as shown in Fig. 2. At this time, the conveying roller 48 is held in a standby position above the processing tray 24 by the lifting bracket 50 so as not to interfere with the discharge of the sheet.

[0053] 7(a), when the rear end of sheet S1 is discharged from discharge port 23 and reaches the processing tray 24, as shown in FIG. 7(b), lifting bracket 50 rotates downward to bring upper transport roller 48 into contact with the upper surface of the sheet on processing tray 24. At this point, the next sheet S2 is transported from image forming unit A and waits in transport path 22.

[0054] Next, the conveying roller 48 is belt-driven by, for example, a drive motor (not shown) to rotate counterclockwise in the drawing. As a result, the sheet S1 is conveyed on the processing tray 24 in the carry-in direction, i.e., in the opposite direction to the stacking tray 25. The take-in rotor 33 is further rotated to convey the sheet S1 until the leading edge in the carry-in direction (the right edge in the drawing) hits the regulating surface of the sheet end regulating means 29.

[0055] 7(c), immediately after the lifting bracket 50 rotates and the transport roller 48 retreats to the upper standby position, the next sheet S2 is transported through the transport path 22 and discharged from the discharge outlet 23 onto the previous sheet S1 on the processing tray 24. As shown in FIG. 8(a), similar to FIG. 7(b), the downward rotation of the lifting bracket 50 causes the transport roller 48 to abut against the upper surface of the sheet on the processing tray 24 and rotate, and the pick-up rotor 33 is further rotated to transport the sheet S2 until its leading edge in the carry-in direction hits the regulating surface of the sheet end regulating means 29.

[0056] In this way, a predetermined number of sheets S are accumulated on the processing tray 24, and when they are aligned in the sheet width direction and the carry-in direction by the sheet alignment mechanism 27, binding processing is performed using the first binding means 51 or the second binding means 52. As shown in Fig. 8(b), the bound sheet bundle Sb is conveyed in the sheet conveying direction on the processing tray 24 by rotating the conveying roller 48 and the pick-up rotor 33 that are in contact with the upper surface of the bound sheet bundle Sb in the reverse direction, and the bundle is discharged onto the stacking tray 25 as shown in Fig. 8(c).

[0057] [Binding operation] The following describes the sheet binding operation by the sheet processing device B. In the following Examples 1 to 4, the sheet width dimension of the sheets to be bound is divided into a case where it is greater than a predetermined value and a case where it is equal to or less than the predetermined value. In each example, the sheets are bound near the corners on the rear side of the device and on the leading edge side in the feed direction.

[0058] [Example 1] In Example 1, A4 size sheets are placed horizontally with their long sides in the sheet width direction, and the sheet width dimension is greater than a predetermined value, and staple binding processing is performed on the corner portions of the sheets using first binding means 51. The following will explain this with reference to Figures 9 to 12.

[0059] 9(a) shows the initial position of FIG. 3, in which the first sheet edge regulating member 37 is in the first position and the side alignment members 65, 66 are in the outermost positions in the sheet width direction. From this initial position, as shown in FIG. 9(b), the first binding means 51 is moved toward the rear of the device in the sheet width direction until the first sheet edge regulating member 37 is positioned integrally with the first binding means 51 in the second position. Thereafter, as shown in FIG. 10(a), the first sheet S1 is discharged onto the processing tray 24.

[0060] 10(b), the sheet carry-in mechanism 26 is operated to bring the leading edge Se of the sheet S in the carry-in direction into contact with the regulating surfaces 41a-43a of the sheet edge regulating portions 41-43, and the side alignment members 65, 66 are moved to regulate both side edges Ss of the sheet S in the sheet width direction, thereby aligning the position of the sheet S in the carry-in direction and the sheet width direction. Next, the side alignment members 65, 66 are returned to their original outermost positions in the sheet width direction, and then the second sheet S2 is discharged onto the preceding sheet S1 on the processing tray 24, as shown in FIG.

[0061] 10(b), the sheet carry-in mechanism 26 and the side alignment members 65, 66 are operated to align sheet S2 together with the sheets stacked below it in the carry-in direction and the sheet width direction, as shown in Fig. 11(b). After a predetermined number of sheets have been aligned on the processing tray 24 in this manner, the side alignment members 65, 66 are moved a predetermined amount in the sheet width direction toward the front of the device, as shown in Fig. 12(a), to shift the sheet stack Sb to a position where the corner portion thereof is aligned with the binding position of the first binding means 51.

[0062] In this state, the first binding means 51 performs the binding process to staple the sheet bundle Sb at the corner portion as shown in Fig. 12(b). The bound sheet bundle Sb is discharged from the processing tray 24 onto the stacking tray 25 as described above with reference to Fig. 8.

[0063] [Example 2] In Example 2, A4 size sheets are arranged vertically with their short sides in the sheet width direction, and the sheet width dimension is equal to or less than a predetermined value, and staple binding processing is performed on the corner portions of the sheets using first binding means 51. The following will be described with reference to Figures 13 to 16.

[0064] 13(a) shows the initial position of FIG. 3, in which the first sheet edge regulating member 37 is in the first position and the side alignment members 65, 66 are positioned at the outermost positions in the sheet width direction. With this initial position, the first sheet S1 is discharged onto the processing tray 24, as shown in FIG. 13(b). At this time, it is convenient to move the side alignment members 65, 66 inward from the outermost positions in advance.

[0065] 14(a), the sheet carry-in mechanism 26 is operated to bring the leading edge Se of the sheet S in the carry-in direction into contact with the regulating surfaces 41a-43a of the sheet edge regulating portions 41-43, and the side alignment members 65, 66 are moved to regulate both side edges Ss of the sheet S in the sheet width direction, thereby aligning the position of the sheet S in the carry-in direction and the sheet width direction. After the side alignment members 65, 66 are returned to the positions shown in FIG. 13(b), the second sheet S2 is discharged onto the preceding sheet S1 in the processing tray 24, as shown in FIG.

[0066] 14(a), the sheet carry-in mechanism 26 and the side alignment members 65, 66 are operated to align sheet S2 together with the sheets stacked below it in the carry-in direction and the sheet width direction, as shown in FIG. 15(a). After a predetermined number of sheets have been aligned on the processing tray 24 in this manner, the first binding means 51 is moved in the sheet width direction toward the rear of the device until the first sheet edge regulating member 37 is positioned integrally with the first binding means 51 at the second position, as shown in FIG.

[0067] This aligns the binding position of the first binding means 51 with the corner portion of the sheet bundle Sb. In this state, the binding process is performed by the first binding means 51, and the sheet bundle Sb is stapled at the corner portion, as shown in Fig. 16. The bound sheet bundle Sb is discharged from the processing tray 24 to the stacking tray 25 as described above with reference to Fig. 8.

[0068] In the above-described embodiment, when the first binding means 51 is used to staple the corner portion of the sheet S on the rear side of the device, the first binding means 51 does not move further toward the rear side of the device (i.e., toward the second binding means 52) by climbing over the first sheet end regulating member 37 that has moved to the second position. Therefore, the first binding means 51 does not interfere with the second binding means 52.

[0069] In a similar conventional structure, the first binding means moves toward the second binding means, climbing over the sheet end regulating member at the rear of the device (located at the position of the first sheet end regulating member 37 in this embodiment), in order to staple the corners of the sheets S. For this reason, the second binding means had to be retracted each time to avoid interference, or positioned at a position offset in the carry-in direction.

[0070] In the configuration of this embodiment, the second binding means 52 can be fixedly disposed on the same line in the sheet width direction as the first binding means 51, as there is no risk of interference with the first binding means 51. Therefore, there is no need for a retreat space for the second binding means 52 or a mechanism for offsetting the sheet stack in the carry-in direction toward the stapleless binding processing position by the second binding means 52, and the entire sheet processing apparatus B can be configured compactly.

[0071] Comparing the above-described first and second embodiments, the movement timings of the first binding means 51 and the first sheet edge regulating member 37 are set to differ depending on the sheet width size. The reason for this is that in the second embodiment, in which the first binding means 51 binds sheets having a small width size, if the first sheet edge regulating member 37 moves to the second position before moving the sheets S on the processing tray 24 in the carry-in direction, as in the first embodiment, the first sheet edge regulating member 37 will be positioned further toward the rear of the device than the sheet edge Ss of the sheets S on the side alignment member 65 side, resulting in the inability to regulate the sheet edge Se. Therefore, it is preferable that the first sheet edge regulating member 37 be positioned at a position where the sheet edge Se can come into contact with the regulating surface 42a of the sheet edge regulating portion 42 when the sheets S discharged onto the processing tray 24 are moved in the carry-in direction.

[0072] The first sheet edge regulating member 37 can be set at multiple "second positions" in the sheet width direction. In this case, all positions closer to the rear of the device than the first position, which is closest to the front of the device, are the second positions. For example, when a sheet S discharged onto the processing tray 24 is moved in the feed direction, the first sheet edge regulating member 37 can be positioned in a finely adjusted manner to match the sheet size in the sheet width direction so that it is always positioned a predetermined distance, for example, 10 mm, toward the front of the device from the position of the sheet edge Ss regulated by the side regulating member 65. This allows the first sheet edge regulating member 37 to be positioned so that the sheet edge Se can always abut against the regulating surface 42a, even for sheets whose sheet width direction size is between the A4 landscape orientation in Example 1 and the A4 portrait orientation in Example 2.

[0073] [Example 3] In Example 3, similar to Example 1, A4 size sheets are placed horizontally with their long sides in the sheet width direction, and the sheet width dimension is greater than a predetermined value, and stapleless binding processing is performed on the corner portions of the sheets using second binding means 52. The following will be described with reference to Figures 17 to 20.

[0074] 17(a) shows the initial position of FIG. 3, in which the first sheet edge regulating member 37 is in the first position and the side alignment members 65, 66 are in the outermost positions in the sheet width direction. From this initial position, as shown in FIG. 17(b), the first binding means 51 is moved toward the rear of the device in the sheet width direction until the first sheet edge regulating member 37 is in the second position together with the first binding means 51. Thereafter, as shown in FIG. 18(a), the first sheet S1 is discharged onto the processing tray 24. At this time, it is convenient to move the side alignment members 65, 66 inward from the outermost positions in advance.

[0075] 18(b), the sheet carry-in mechanism 26 is operated to bring the leading edge Se of the sheet S in the carry-in direction into contact with the regulating surfaces 41a-43a of the sheet edge regulating portions 41-43, and the side alignment members 65, 66 are moved to regulate both side edges Ss of the sheet S in the sheet width direction, thereby aligning the position of the sheet S in the carry-in direction and the sheet width direction. Next, the side alignment members 65, 66 are returned to the positions shown in FIG. 18(a), and then the second sheet S2 is discharged onto the preceding sheet S1 in the processing tray 24, as shown in FIG.

[0076] 18(b), the sheet carry-in mechanism 26 and the side alignment members 65, 66 are operated to align sheet S2 together with the sheets stacked below it in the carry-in direction and the sheet width direction, as shown in Fig. 19(b). After a predetermined number of sheets have been aligned on the processing tray 24 in this manner, as shown in Fig. 20(a), the side alignment members 65, 66 are moved in the sheet width direction toward the rear of the device until the side alignment member 65 closest to the second binding means 52 reaches its outermost position, and the sheet stack Sb is shifted to a position where the corner portion thereof is aligned with the binding position of the second binding means 52.

[0077] In this state, the second binding means 52 performs a binding process to staple-free bind the sheet bundle Sb by crimping the corners as shown in Fig. 20(b). The bound sheet bundle Sb is discharged from the processing tray 24 onto the stacking tray 25 as described above with reference to Fig. 8.

[0078] [Example 4] In Example 4, B5 size sheets are placed horizontally with their long sides in the sheet width direction, and the sheet width dimension is equal to or less than a predetermined value, and stapleless binding processing is performed on the corner portions of the sheets using second binding means 52. The following will be described with reference to Figures 21 to 25.

[0079] 21(a) shows the initial position of FIG. 3, in which the first sheet edge regulating member 37 is in the first position and the side alignment members 65, 66 are positioned at the outermost positions in the sheet width direction. With this initial position, the first sheet S1 is discharged onto the processing tray 24, as shown in FIG. 21(b). At this time, it is convenient to move the side alignment members 65, 66 inward from the outermost positions in advance.

[0080] 22(a), the sheet carry-in mechanism 26 is operated to bring the leading edge Se of the sheet S in the carry-in direction into contact with the regulating surfaces 41a-43a of the sheet edge regulating portions 41-43, and the side alignment members 65, 66 are moved to regulate both side edges Ss of the sheet S in the sheet width direction, thereby aligning the position of the sheet S in the carry-in direction and the sheet width direction. After the side alignment members 65, 66 are returned to the positions shown in FIG. 21(b), the second sheet S2 is discharged onto the preceding sheet S1 in the processing tray 24, as shown in FIG. 22(b).

[0081] 22(a), the sheet carry-in mechanism 26 and the side alignment members 65, 66 are operated to align sheet S2 together with the sheets stacked below it in the carry-in direction and the sheet width direction, as shown in Fig. 23(a). After a predetermined number of sheets have been aligned on the processing tray 24 in this manner, the side alignment members 65, 66 are shifted a predetermined amount in the sheet width direction toward the rear of the device, so that the sheet stack Sb reaches a position where the corner portion of the sheet stack Sb is positioned before the binding position of the second binding means 52, as shown in Fig. 23(b).

[0082] Next, the first binding means 51 is moved in the sheet width direction toward the rear of the device until the first sheet end regulating member 37 is positioned integrally with the first binding means 51 at the second position, as shown in Fig. 24(a). Furthermore, the side alignment members 65, 66 are moved in the sheet width direction toward the rear of the device until the side alignment member 65 closer to the second binding means 52 reaches its outermost position, and the sheet stack Sb is shifted to a position where the corner portion thereof is aligned with the binding position of the second binding means 52, as shown in Fig. 24(b).

[0083] The shifting of the sheet stack Sb described above with reference to FIG. 23A and the movement of the first sheet edge regulating member 37 to the second position described above with reference to FIG. 24A can be performed simultaneously. At this time, the condition is that the edge Se of the shifting sheet stack Sb maintains contact with the regulating surface 42a of the moving first sheet edge regulating member 37 without moving away from it. For example, if the shifting of the sheet stack Sb is performed at the same speed as or faster than the movement of the first sheet edge regulating member 37 to the second position, it is easier to maintain the contact between the sheet stack edge Se and the regulating surface 42a, which is advantageous.

[0084] 24(b), the vicinity of the corner of the sheet stack Sb is lifted from the paper loading surface 24a by the guide portion 24b, which is slightly raised from the paper loading surface 24a, at the corner portion on the rear side of the device in the sheet width direction and on the leading edge side in the carry-in direction of the processing tray 24, as shown in FIG. 25(a). As a result, the corner portion of the sheet stack Sb is smoothly guided into the opening of the pressure binding portion 72 of the second binding means 52.

[0085] The sheet bundle Sb can also be shifted so that the corner portion thereof is guided into the opening of the second binding means 52 while the first sheet end regulating member 37 is moving to the second position in FIG. 24(a). However, since the sheet bundle Sb is pressed onto the paper mounting surface 24a by the guide portion 57 of the first sheet end regulating member 37, it is preferable that the first sheet end regulating member 37 is positioned closer to the second binding means 52, since this makes it easier to guide the corner portion of the sheet bundle Sb into the opening of the second binding means 52. Therefore, in the embodiment, After the first sheet end regulating member 37 has completed its movement to the position closest to the second binding means 52, the sheet bundle Sb is shifted to guide the corner portion to the opening of the second binding means 52.

[0086] In this state, the second binding means 52 performs the binding process, and stapleless binding is performed on the sheet bundle Sb by crimping the corners as shown in Fig. 25(b). The bound sheet bundle Sb is discharged from the processing tray 24 onto the stacking tray 25 as described above with reference to Fig. 8.

[0087] The positional relationship between the sheet edge Se and the first sheet edge regulating member 37 when the sheet S discharged onto the processing tray 24 is moved in the carry-in direction, as described above in relation to the first and second embodiments, is preferably set in the same manner in the stapleless binding process using the second binding means 52 in the third and fourth embodiments. This allows the first sheet edge regulating member 37 to be positioned so that the sheet edge Se can always come into contact with the regulating surface 42a, in accordance with the sheet size in the sheet width direction of the sheet S discharged onto the processing tray 24.

[0088] In the above embodiment, the sheet conveying direction in which the sheet S is discharged from the discharge port 23 to the processing tray 24 and the carry-in direction in which the sheet S discharged onto the processing tray 24 is carried toward the sheet edge regulating means 29 are configured to be opposite to each other, i.e., switchback conveyance, when the sheet processing device B is viewed in a plan view as shown in FIG. 3. In another embodiment, the sheet conveying direction and the carry-in direction can also be configured to intersect (e.g., perpendicular to) each other when viewed in a plan view. In this case, the "sheet edge Se" in the sheet width direction described above is the sheet edge in the direction intersecting (perpendicular to) the carry-in direction. In either case, the direction along the sheet edge Se regulated by the sheet edge regulating means 29 (sheet edge regulating members 36-38) remains the sheet width direction.

[0089] In the above embodiment, the first sheet edge regulating member 37 is configured to move between the first position and the second position using the movement of the first binding device 51 in the sheet width direction and the biasing force of the coil spring 53 as drive sources. In another embodiment, a different drive source can be used to move the first sheet edge regulating member 37. For example, the first sheet edge regulating member 37 can be moved using a dedicated drive motor or solenoid. Alternatively, the first sheet edge regulating member 37 may be moved using a drive motor for another component, such as the side alignment members 65, 66 or the first binding device 51, as a drive source.

[0090] The present invention has been described above in relation to preferred embodiments, but it goes without saying that the present invention is not limited to the above embodiments and can be implemented with various changes or modifications within its technical scope. [Explanation of symbols]

[0091] A Image forming unit B. Sheet processing device C Image reading unit D Document feed unit 24 Processing Tray 24a Paper page 25 Loading Tray 26 Sheet loading mechanism 27 Sheet alignment mechanism 29 Sheet edge control means 37 First sheet end regulating member 38 Second sheet end regulating member 51 First binding means 52 Second binding means 65,66 Side alignment means

Claims

1. A sheet processing device that performs binding processing on a sheet stack, a tray for stacking the conveyed sheets one by one to form a sheet bundle; a plurality of abutting means arranged in front and rear directions of the sheet processing apparatus, against which the edge of the sheet on the tray abuts; a shift unit that shifts the sheet that has been abutted against the abutting means in the front-to-rear direction; a stapler configured to be able to staple a corner portion of the sheet stack abutted against the abutting means and on the rear side in the front-rear direction of the sheet stack; a stapleless binding unit that is provided on the rear side of the abutting means and is configured to be able to perform stapleless binding on a corner portion of the sheet bundle that is abutted against the abutting means and that is on the rear side; Equipped with The abutting means is configured such that an abutting member disposed at the innermost side in the front-rear direction is movable in the front-rear direction on the front side of the stapleless binding unit in the front-rear direction, When the stapler performs the staple processing on the corner portion of a sheet stack consisting of specified sheets, the sheet processing device is characterized in that the staple processing is performed on the corner portion of the sheet stack closer to the front than the abutment member that has moved to the rear by moving the abutment member toward the rear and shifting the sheets toward the front by the shift unit.

2. The sheet processing device described in Claim 1, characterized in that the needleless binding unit is fixedly positioned further back than the abutting member, and is configured to be able to perform the needleless binding process on the corner portion of the sheet stack by shifting the sheet that has been abutted against the abutting means to the back side using the shift section.

3. A sheet processing device as described in claim 1, characterized in that the abutment member moves to the rear side as the stapler moves from the front side to the rear side in the front-to-rear direction, and moves to the front side as the stapler moves from the rear side to the front side.

4. an image forming unit that forms an image on a sheet; an image reading unit disposed above the image forming unit; an internal space defined between the image forming unit and the image reading unit; a sheet processing unit that is mounted in the internal space of the body and that performs a binding process on a sheet stack made up of sheets on which images have been formed by the image forming unit, 4. An image forming apparatus, wherein the sheet processing unit is a sheet processing apparatus according to claim 1.

Images