Sheet processing apparatus and image forming system equipped with same

Abstract

To provide a sheet processing device that resolves driving force shortage of an alignment member to stably perform bundle shifting by changing control according to a bundle shifting method by sheet size and the number of sheets.SOLUTION: Sheets forming the same bundle fed to a placement part after executing sheet bundle movement are subjected to one sheet sifting for moving to a shift position sheet by sheet after being conveyed to the placement part, by being aligned to a center of the placement part by alignment means every time when one sheet is arranged, when the sheets placed on the placement part are recognized to be in predetermined size or more, and to be the predetermined number of sheets or more by recognizing means for recognizing information about the size and the number of the sheets fed to the placement part, and by being made to bundle-move to the shift position upon center alignment of the number of sheets.SELECTED DRAWING: Figure 13

Description

[Technical Field]

[0001] The present invention relates to an improvement in a sheet processing apparatus that shifts sheets and performs predetermined processing on them. [Background technology]

[0002] Generally, a post-processing device (finisher) that collates and stacks sheets on a processing tray after forming images on the sheets in an image forming apparatus and performs a binding process is widely known. Known binding methods include a stapler device that uses staples to perform the binding process, and a pressure binding device that presses and deforms stacked sheets to bind them.

[0003] Patent Document 1 discloses an apparatus that is connected to the sheet discharge port of an image forming apparatus, carries image-formed sheets from a carry-in path onto a processing tray, stacks them, binds them using a pressure binding device on the processing tray, and then stores them in a downstream stack tray.The same document also discloses an apparatus that positions the sheet stack that has been sent from the sheet discharge path to the processing tray and stacked by abutting and regulating the rear end in the sheet discharge direction, aligns the sheet stack in the sheet width direction, and then shifts the sheet stack in the width direction and performs pressure binding, thereby reducing misalignment of the sheet stack. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-020823 Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, post-processing mechanisms are widely known in which sheets on which images have been formed in an image forming apparatus are stacked into bundles in a post-processing device, bound, and then stored in a stack tray. Also known are devices that crimp-staple the sheet bundles stacked on the processing tray (see, for example, Patent Document 1). In recent years, improvements in crimp-stapling devices have increased the maximum number of sheets that can be crimp-stapled at one time. When performing the bundle shifting operation disclosed in Patent Document 1 on a large bundle of sheets, the shift function of the alignment member may not provide sufficient driving force. Furthermore, installing a larger drive source raises concerns about the device's cost and size.

[0006] SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a sheet processing apparatus that can stably shift a stack by changing the control of the stack shifting method depending on the size and number of sheets, thereby eliminating the insufficient driving force of the alignment member. [Means for solving the problem]

[0007] The sheet processing apparatus of the present invention comprises: a conveying unit for conveying a sheet in a predetermined conveying direction; a sheet receiving unit configured to receive the sheet conveyed by the sheet conveying unit; a stacking section on which sheets fed from the stacking section are stacked; of the sheet , perpendicular to the conveying direction The sheet stacking device includes an alignment unit that performs an alignment operation to align the sheet width direction and an alignment operation that moves the aligned sheet to a shift position in the sheet width direction, a recognition unit that recognizes information about the size and number of sheets sent to the stacking unit, and a control unit that controls the alignment unit, and the control unit Each time a sheet is placed on the sheet placement section, the sheet is aligned by the alignment means, and when the number of sheets reaches an upper limit number at which the alignment means can move the sheets to the shift position based on the recognition result of the recognition means, When the recognition means recognizes that the sheets to be placed on the stacking section are equal to or larger than a predetermined size and equal to or larger than a predetermined number of sheets, the sheets are aligned by the alignment means each time they are placed, and after the predetermined number of sheets have been aligned, the alignment means executes a stack movement operation to the shift position, and after the stack movement operation is executed, the sheets are sent to the stacking section. 、 The bundle transfer operation was performed The sheet stackThe alignment means is controlled so that sheets forming the same bundle are conveyed to the stacking section and then shifted one by one to the shift position. [Effects of the Invention]

[0008] The present invention performs alignment operations in the sheet width direction for sheets discharged onto the processing tray up to a predetermined number of sheets, and then shifts the sheet stack in the width direction, and for sheets discharged onto the processing tray after the predetermined number of sheets in the same job, shifts (one sheet shift) each time they are discharged, thereby eliminating the lack of driving force of the alignment member. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is an explanatory diagram of the overall configuration of an image forming system according to the present invention; [Figure 2] FIG. 2 is an explanatory diagram of the overall configuration of a post-processing device in the image forming system of FIG. 1. [Figure 3] FIG. 3 is an enlarged view of the main part of the pathway of the device in FIG. 2. [Figure 4] 10 shows the movement trajectories of the staple unit and the eco-binding means. [Figure 5] 3 is an explanatory diagram showing the positional relationship between an alignment position and a staple unit in the device of FIG. 2. FIG. [Figure 6] Binding means slide mechanism diagram. [Figure 7] FIG. 3 is an explanatory diagram of a first embodiment of a differential means in the device of FIG. 2; [Figure 8] FIG. 3 is an explanatory diagram of a second embodiment of the differential means in the device of FIG. 2; [Figure 9] 3A and 3B show the binding means according to the present invention, in which FIG. 3A is a diagram illustrating the configuration of a staple unit, and FIG. 3B is a diagram illustrating the configuration of an eco-binding unit. [Figure 10] FIG. 3 is an explanatory diagram of a sheet bundle discharge mechanism in the device of FIG. 2. [Figure 11] FIG. 2 is a block diagram showing a control configuration in the device of FIG. 1. [Figure 12] Binding process paper discharge operation flow diagram. [Figure 13] 2 is a flow chart showing the crimp binding operation of the device shown in FIG. 1. [Figure 14] FIG. 10 is an explanatory diagram of small size pressure binding operation (center alignment). [Figure 15] An explanatory diagram of small size pressure binding operation (bundle shift). [Figure 16] An explanatory diagram of the small size crimp binding operation (from binding operation to ejection). [Figure 17] FIG. 10 is an explanatory diagram of the pressure binding operation (bundle shift) for large size sheets of a predetermined number or less. [Figure 18] FIG. 10 is an explanatory diagram of the crimp binding operation (from binding operation to discharge) for a predetermined number of large-size sheets or less. [Figure 19] FIG. 10 is an explanatory diagram of the pressure binding operation (center alignment) for a predetermined number of large-size sheets. [Figure 20] An explanatory diagram of the pressure binding operation (bundle shift and subsequent paper ejection) for large size sheets exceeding the specified number. [Figure 21] FIG. 10 is an explanatory diagram of the crimp binding operation (binding operation) for a large-size sheet exceeding a predetermined number. [Figure 22] FIG. 10 is an explanatory diagram of the crimp binding operation (discharge) for a large-size sheet exceeding a predetermined number. [Figure 23] Operation flow when the number of sheets that can be laminated and bound is exceeded. DETAILED DESCRIPTION OF THE INVENTION

[0010] In this specification, "offset conveyance of a sheet stack" refers to shifting the position (widthwise shifting) of sheets conveyed from the sheet discharge outlet in a direction perpendicular (or intersecting) to the sheet conveyance direction, and "offset amount" refers to the amount of movement. Furthermore, "alignment of a sheet stack" refers to aligning sheets of different sizes conveyed from the sheet discharge outlet based on a reference (center reference or one-side reference). Therefore, "offsetting sheets after aligning" means aligning sheets of different sizes based on a reference, and then shifting the positions of the entire sheets in a direction perpendicular to the sheet conveyance direction. Here, "perpendicular" includes not only cases where the sheets intersect at an angle of exactly 90 degrees, but also cases where the sheets intersect at an angle of approximately 90 degrees and cases where the sheets are substantially or nearly perpendicular.

[0011] [Image formation system] The present invention will be described in detail below with reference to the preferred embodiments shown in the drawings. As shown in Figure 1, the present invention relates to a sheet post-processing device B that performs binding, folding, and other post-processing on sheets on which images have been formed by an image forming device A, and an image forming system equipped with the same.

[0012] Image forming apparatus A forms an image on a sheet based on image data read by a copier, facsimile machine, printer, printing device, etc., or transferred from an external device. In other words, image forming apparatus A is configured as an image forming unit of a computer network output terminal, copier system, facsimile system, etc., and adopts either a configuration in which an image is formed on a sheet based on data read by an image reading unit within the system (standalone configuration), or a configuration in which an image is formed on a sheet based on image data created or read within a computer network (network configuration). The image forming apparatus A and sheet post-processing apparatus B will be described in order according to Figure 1 showing the network configuration.

[0013] [Image forming equipment] An image forming apparatus A in the image forming system shown in Figure 1 will now be described. The image forming apparatus A shown in the figure is an electrostatic printing mechanism, and is composed of an image forming unit A1, a scanner unit A2, and a feeder unit A3. The apparatus housing 1 is provided with mounting legs 25 for installation on an installation surface (for example, the floor). Also built into the apparatus housing are a paper feed unit 2, an image forming unit 3, a paper discharge unit 4, and a data processing unit 5.

[0014] The paper feed unit 2 is composed of cassette mechanisms 2a to 2c that store sheets of multiple sizes on which images are to be formed, and feeds sheets of a size specified by the main body control unit 90 to a paper feed path 6. For this purpose, multiple cassettes 2a to 2c are detachably arranged in the device housing 1, and each cassette has a built-in separation mechanism that separates the sheets inside one by one, and a paper feed mechanism that feeds out the sheets. The paper feed path 6 is provided with a transport roller 7 that feeds sheets supplied from the multiple cassettes 2a to 2c downstream, and a registration roller pair 8 at the end of the path that aligns the leading edges of each sheet.

[0015] The above-mentioned paper feed path 6 is connected to a large-capacity cassette 2d and a manual feed tray 2e, with the large-capacity cassette 2d being an optional unit that stores sheets of a size that are consumed in large quantities, and the manual feed tray 2e being configured to be able to supply special sheets such as cardboard sheets, coated sheets, and film sheets that are difficult to separate and feed.

[0016] The image forming unit 3 is an example of an electrostatic printing mechanism, and includes a photosensitive member 9 (drum, belt), a light emitter 10 that emits an optical beam onto the photosensitive member, a developer 11, and a cleaner (not shown) that are arranged around the rotating photosensitive member. The image shown in the figure shows a monochrome printing mechanism, in which a latent image is optically formed on the photosensitive drum 9 by the light emitter, and toner ink is applied to the latent image by the developer 11.

[0017] Then, in accordance with the timing of image formation on the photosensitive member 9, the sheet is sent from the paper feed path 6 to the image forming unit 3, where the image is transferred onto the sheet by a transfer charger 12, and then fixed by a fixing unit (roller) 13 arranged on the paper discharge path 14. On the paper discharge path 14, paper discharge rollers 15 and a paper discharge outlet 16 are arranged, and the sheet is transported to a sheet post-processing device B, which will be described later.

[0018] The scanner unit A2 described above is composed of a platen 17 on which an image document is placed, a carriage 18 that moves back and forth along the platen, a light source mounted on the carriage, and a reduction optical system 20 (a combination of mirrors and lenses) that guides reflected light from the document on the platen to photoelectric conversion means 19. Reference numeral 21 in the figure denotes a second platen (traveling platen), which reads an image on a sheet sent from feeder unit A3 using the carriage 18 and reduction optical system 20 described above. The photoelectric conversion means 19 photoelectrically converts the image data and electrically transfers it to image forming unit 3.

[0019] The feeder unit A3 is composed of a paper feed tray 22, a paper feed path 23 that guides sheets fed from the paper feed tray to a traveling platen 21, and a paper discharge tray 24 that stores documents whose images have been read by the platen.

[0020] The image forming apparatus A is not limited to the above-mentioned mechanism, and can employ printing mechanisms such as an offset printing mechanism, an inkjet printing mechanism, and an ink ribbon transfer printing mechanism (thermal transfer ribbon printing, dye sublimation ribbon printing, etc.).

[0021] [Sheet post-processing device] The sheet post-processing device B is a device for post-processing sheets discharged from the paper discharge port 16 of the image forming device A, and is equipped with: (1) a function for stacking and storing image-formed sheets (first and third processing devices B1, B3; printout mode), (2) a function for storing image-formed sheets in portions (third processing device B3; jog sorting mode), (3) a function for collating and accumulating image-formed sheets and binding them (first processing device B1; binding mode), and (4) a function for collating and binding the image-formed sheets, and then folding them to complete the binding process (second processing device B2; binding mode).

[0022] In the present invention, the sheet post-processing device B does not need to have all of the above-mentioned functions, and may be configured appropriately according to the device specifications (design specifications). In this case, too, a processing section (first processing section B1) that collates and accumulates sheets, a first binding section (staple binding unit 47 described later) that has a high processing capacity in terms of the number of sheets that can be processed in this processing section, and a second binding section (staple-less binding unit 51 described later) that has a lower processing capacity in terms of the number of sheets that can be processed than the first binding section, and a stack configuration in which sheets are stored after being bound by the selected binding section are required.

[0023] 2 shows the detailed configuration of sheet post-processing device B. Sheet post-processing device B has an inlet 26 connected to the sheet discharge outlet 16 of image forming device A, and stores sheets carried in through this inlet in a storage section (a first stack tray 49, a second stack tray 61, and a third stack tray 71, which will be described later) after post-processing. The illustrated device transfers sheets sent to sheet carry-in path 28 from first processing section B1 to first stack tray 49 (hereinafter referred to as the "first tray" or "loading section"), from second processing section B2 to second stack tray 61 (hereinafter referred to as the "second tray"), and from third processing section B3 to third stack tray 71 (hereinafter referred to as the "third tray").

[0024] The first processing unit B1 is disposed at a path exit (sheet discharge port) 35 of the sheet carry-in path 28, and collates and stacks the sequentially fed sheets, performs a binding process on them, and then stores them in a first stack tray (first storage unit) 49. The second processing unit B2 is disposed at a path exit 62 (the end of a second switchback path described later) branching off from the sheet carry-in path 28, and collates and stacks the sequentially fed sheets, performs a binding process on them, and then folds them and stores them in a second stack tray (second storage unit) 61. The third processing unit B3 is incorporated into the sheet carry-in path 28, and offsets the conveyed sheets by a predetermined amount in the orthogonal direction to sort them, and then stores them in a third stack tray (third storage unit) 71. Each component will be described in detail below.

[0025] [Device housing] 2, sheet post-processing device B includes device housing 27, sheet feed path 28 built into the device housing and having inlet 26 and outlet 35, first processing section B1, second processing section B2, and third processing section B3 that process sheets fed from this path, and first, second, and third trays 49, 61, and 71 that store sheets fed from each processing section. The illustrated device housing 27 is disposed at approximately the same height as housing 1 of image forming device A located upstream, and is connected to outlet 16 of image forming device A and inlet 26 of sheet post-processing device B from the installation surface.

[0026] [Sheet entry route (transport route)] Sheet carry-in path 28 is a straight path that crosses device housing 27 in a substantially horizontal direction, and includes carry-in entrance 26 that connects to discharge outlet (main body discharge outlet) 16 of image forming device A, and discharge outlet 35 located on the opposite side of the device across from the carry-in entrance. This sheet carry-in path 28 is provided with conveyance rollers 29 (sheet conveying means such as rollers or belts) that convey the sheet from carry-in entrance 26 toward discharge outlet 35, discharge rollers 36 (which may be belts) arranged at discharge outlet 35, an entrance sensor S1 that detects the leading and trailing edges of the sheet carried into the path, and a discharge sensor S2 that detects the leading and trailing edges of the sheet at the path discharge outlet.

[0027] The sheet carry-in path 28 is connected so as to distribute and transport sheets from the carry-in entrance 26 to the first processing section B1 and the second processing section B2, with the second processing section B2 connected to the upstream side in the path discharge direction and the first processing section B1 connected to the downstream side. The sheet carry-in path 28, which has a substantially linear shape, branches off to transport the sheet from the carry-in entrance 26 toward the second processing section B2, and then guides the sheet to the first processing section B1 located downstream of the path discharge outlet 35.

[0028] Furthermore, a third discharge path (printout discharge path) 30 is connected to the above-mentioned sheet carry-in path 28, which guides sheets that are not post-processed in the first and second processing sections B1 and B2 to a third tray 71, and is configured to guide the sheets to the third tray (overflow tray) 71. A third processing section B3 is built into this sheet carry-in path 28, and this processing section jog-sorts sheets transported along the path by offsetting them in a direction perpendicular to the sheet discharge direction. In other words, the sheet carry-in path 28 has a built-in third processing section B3, and sheets jog-sorted by this processing section are stored in the third tray 71.

[0029] 2, the sheet carry-in path 28 is arranged in the order of "third discharge path 30," "second discharge path 32," and "first discharge path 31" downstream from the carry-in entrance 26, with first path switching means 33 and second path switching means 34 disposed at the illustrated positions. In addition, the second discharge path 32 and the first discharge path 31 are configured as switchback paths that reverse the sheet transport direction and guide the sheet to each processing section.

[0030] The third discharge path 30 guides the sheets sent from the carry-in entrance 26 to the third tray, the second discharge path 32 guides the sheets sent from the carry-in entrance 26 to the second tray 61, and the first discharge path 31 guides the sheets sent from the carry-in entrance 26 to the first tray 49. Then, the sheets guided to the third tray 71 are jog sorted at the third processing section B3 on the carry-in path, the sheets guided to the second tray 61 are bound at the second processing section B2, and the sheets guided to the first tray 49 are bound at the first processing section B1.

[0031] The first path switching means 33 is composed of a flapper guide that changes the sheet transport direction, and is connected to a driving means (electromagnetic solenoid, minimotor, etc.) not shown. This switching means 33 selects whether to guide the sheet from the carry-in entrance 26 to the third discharge path 30 or to the first and second discharge paths 31 and 32. The second path switching means 34 selects whether to guide the sheet sent from the carry-in entrance 26 to the second processing section B2 or to the first processing section B1 downstream of that. A driving means not shown is also connected to the second path switching means 34. In addition, a punch unit 50 that punches holes in the carried-in sheet is arranged in the sheet carry-in path 28.

[0032] [First processing section (mounting section)] The first processing section B1 is arranged downstream of the sheet carrying-in path 28 and is composed of a processing tray 37 that collates and accumulates sheets sent from the sheet discharge outlet 35, and a binding processing mechanism that binds the accumulated sheet stack. As shown in Fig. 2, a step is formed at the sheet discharge outlet 35 of the sheet carrying-in path 28, and the processing tray 37 is arranged below the step, and a first sheet discharge path (switchback path) 31 is formed between the sheet discharge outlet 35 and the processing tray that reverses the conveying direction from the sheet discharge outlet and guides the sheets onto the tray.

[0033] Between the sheet discharge port 35 and the processing tray 37, there is disposed a sheet carry-in mechanism that carries sheets from the sheet discharge port onto the tray, and in the processing tray 37, there is disposed a positioning mechanism that positions the sheets at a predetermined binding position, and a sheet bundle carry-out mechanism that carries the bound sheet bundle downstream to a first tray 49. Each component will be described later.

[0034] 2 bridges the sheet fed from the paper discharge port 35 between itself and the downstream first tray 49. That is, the sheet fed from the paper discharge port 35 is configured to be bridge-supported with its leading edge on the uppermost sheet of the downstream first tray 49 and its trailing edge on the processing tray 37.

[0035] [Second processing section] A second discharge path (second switchback path) 32 branches off and connects to the sheet carry-in path 28 upstream of the first discharge path (first switchback path) 31, and guides sheets from this discharge path to the second processing section B2. The second processing section B2 collates and stacks the sheets sent from the sheet carry-in path 28, binds the center, and inner-folds the sheets (hereinafter referred to as "magazine finishing"). A second tray 61 is disposed downstream of the second processing section B2 and stores the bound sheet stack.

[0036] The second processing section B2 is composed of a guide member 66 that accumulates sheets in a bundle, a regulating stopper 67 (the one shown is a leading edge regulating stopper) that positions the sheets at a predetermined position on the guide member, a staple device 63 (saddle stitching staple unit) that binds the center of the sheets positioned by the stopper, and a folding mechanism (a pair of folding rolls 64 and a folding blade 65) that folds the sheet bundle at the center after binding.

[0037] The saddle stitch staple unit 63 employs a mechanism for binding a sheet stack by moving the head unit and anvil unit along the center line of the sheets while the unit holds the sheet stack between them, as disclosed in Japanese Patent Application Laid-Open Nos. 2008-184324 and 2009-051644. The folding mechanism employs a configuration in which a folding blade 65 inserts the fold of the sheet stack into a pair of folding rolls 64 that are pressed against each other, as shown in Fig. 2, and the sheets are folded by the rolling of the pair of rolls. Such a mechanism is also disclosed in Japanese Patent Application Laid-Open Nos. 2008-184324 and 2009-051644.

[0038] The illustrated first processing section B1 and sheet carry-in path 28 are disposed in a substantially horizontal direction, the second discharge path 32 that guides sheets to the second processing section B2 is disposed in a vertical direction, and the guide member 66 that collates and accumulates the sheets is disposed in a substantially vertical direction. In this way, by disposing the sheet carry-in path 28 in a direction that crosses the device housing 27 and disposing the processing paths (sections) 32 and B2 in a vertical direction, it is possible to slim down the device.

[0039] A second tray 61 is disposed downstream of the second processing section B2 and stores the folded sheet stacks in a magazine shape. The illustrated second tray 61 is disposed below the first tray 49. This is because the device specifications specify that the first tray 49 is used more frequently than the second tray 61, and so the first tray 49 is set at a height position that makes it easy to remove the sheets on the tray.

[0040] [Third Processing Section] In the sheet carry-in path 28, a third discharge path 30 is formed upstream of the first discharge path 31 and the second discharge path 32, and guides the sheet from the carry-in entrance 26 to the third tray 71. A roller shift mechanism (not shown) is disposed in the path (the carry-in path or the third discharge path) that guides the sheet from the carry-in entrance 26 to the third tray 71, to offset the sheet being conveyed by a predetermined amount in the perpendicular direction.

[0041] Then, the sheets are sorted into sets from the carry-in entrance 26 and stored on the third tray 71 by offsetting the orthogonal orientation of the sheets. Various mechanisms are known for this jog sorting mechanism, and therefore a description thereof will be omitted.

[0042] [Configuration of the first processing section] The configurations of the sheet carry-in mechanism, sheet positioning mechanism, binding mechanism, and sheet bundle carry-out mechanism of the first processing section B1 will be described below.

[0043] [Sheet loading mechanism] As shown in Figure 3, between the paper discharge outlet 35 and the processing tray 37 are arranged reversal conveying mechanisms 41 and 42 that switchback-convey the sheet from the paper discharge outlet in the paper discharge direction and the opposite direction to the paper discharge direction, a guide mechanism (sheet guide member) 44 that guides the sheet toward the tray, and a pick-up rotating body 46 (hereinafter referred to as "pick-up means 46") that guides the sheet to the leading edge regulating means.

[0044] The reverse transport mechanism is composed of a lifting roller 41 that moves up and down between an operating position where it engages with the sheet being transported onto the processing tray and a separated standby position, and a paddle rotor 42 that transports the sheet in the opposite direction to paper discharge, and this lifting roller 41 and paddle rotor 42 are attached to a swinging bracket 43.

[0045] A swing bracket 43 is arranged on the device frame 27a so as to be swingable around a rotation axis 36x (the illustrated one is the paper discharge roller axis), and the rotation axes of the lift roller 41 and the paddle rotor 42 are supported by bearings on this bracket. An elevator motor (not shown) is connected to the swing bracket 43, and moves the mounted lift roller 41 and paddle rotor 42 up and down between an operating position where they engage with the sheet and a standby position where they are spaced apart from the sheet.

[0046] A drive motor (not shown) is connected to the lift roller 41 and the paddle rotor 42, and drive is transmitted to rotate the lift roller 41 in forward and reverse directions and the paddle rotor 42 in the reverse direction (opposite the direction of paper discharge). The processing tray 37 is also provided with a driven roller 48 that is in pressure contact with the lift roller 41, and nips a single sheet or a bundle of sheets and conveys them downstream.

[0047] Between the lift roller 41 and the take-in rotor 46 described below, there is disposed a guide mechanism that guides the trailing end of a sheet carried onto the processing tray toward the regulating means 38, and the illustrated one is composed of a sheet guide member 44 that moves up and down from the dotted line state in FIG. 3 to the solid line state, and this guide member 44 retracts to the dotted line position when the sheet is carried out from the paper discharge outlet 35, and guides the trailing end of the sheet onto the processing tray after it has passed the paper discharge outlet 35. For this reason, a drive mechanism (not shown) is connected to the sheet guide member 44, which moves up and down in accordance with the timing of guiding the trailing end of the sheet from the paper discharge outlet 35 onto the processing tray. Note that these take-in means are controlled by take-in control means (not shown).

[0048] [Seat positioning mechanism] Positioning mechanisms 38 and 39 for positioning sheets at predetermined binding positions are arranged on the processing tray 37, and the illustrated one is composed of a sheet end regulating means 38 for regulating the rear end of the sheet by hitting it, and a side edge alignment means 39 for positioning the side edges of the sheet at reference positions (center reference, one side reference).

[0049] The sheet edge regulating means 38 is composed of a stopper member that abuts and regulates the rear end of the sheet, as shown in Fig. 3. Also, the side edge alignment member 39 will be described later with reference to Fig. 5, but in the illustrated device, sheets are discharged from the sheet carry-in path 28 with a center reference, and depending on the binding mode, the sheets are positioned with the same center reference or with a side reference on one side.

[0050] [Side edge alignment means (alignment means)] 5, the side edge alignment plates 39F, 39R protrude upward from the paper loading surface 37a of the processing tray 37, have regulating surfaces 39x that engage with the side edges of the sheets, and are arranged in a pair on the left and right so as to face each other. This pair of side edge alignment means 39 is arranged on the processing tray 37 so that it can move back and forth with a predetermined stroke. This stroke is set based on the size difference between the maximum size sheet and the minimum size sheet and the offset amount by which the sheet stack is moved to the left or right after alignment (offset transport).

[0051] In other words, the movement strokes of the left and right side edge alignment means 39F, 39R are set based on the movement amount for aligning sheets of different sizes and the offset amount of the sheet stack after alignment. The offset movement of the side edge alignment plates 39F, 39R moves the sheets fed out based on the center reference by a predetermined amount to the right for right-corner binding and to the left for left-corner binding. This offset movement can be performed one by one each time a sheet is fed into the processing tray 37 (for each fed-in sheet), or by moving the entire stack for binding after aligning the sheets into a stack.

[0052] 5, the side edge alignment means 39 is made up of a right edge alignment member 39F (on the front side of the apparatus) and a left edge alignment member 39R (on the rear side of the apparatus), and both side edge alignment members have regulating surfaces 39x that engage with the side edges of sheets, which are supported by the processing tray 37 so as to move toward or away from each other. The processing tray 37 is provided with a slit groove (not shown) that penetrates from the front to the back, and the side edge alignment means 39, which has regulating surfaces 39x that engage with the side edges of sheets, is slidably fitted into the upper surface of the tray through this slit.

[0053] Each side edge alignment member 39F, 39R is slidably supported on a plurality of guide rollers 80 (which may be rail members) on the rear side of the tray, and is integrally formed with a rack 81. Alignment motors M1, M2 are connected to the left and right racks 81 via pinions 82. These left and right alignment motors M1, M2 are configured as stepping motors, and are configured to detect the positions of the left and right side edge alignment members 39F, 39R using position sensors (not shown), and to move each alignment member by a specified amount in either the left or right direction based on the detected value.

[0054] Instead of using the rack-and-pinion mechanism shown in the figure, it is also possible to fix each side edge alignment member 39F, 39R to a timing belt and connect the belt with a pulley to a motor that reciprocates the belt left and right.

[0055] With this configuration, the control means 95, which will be described later, causes the left and right side edge alignment members 39F, 39R to wait at predetermined standby positions (a position equal to the sheet width size plus α) based on sheet size information provided from the image forming apparatus A or the like. When performing "multi-binding," the sheet is carried onto the processing tray 37, and the alignment operation begins when the sheet edge hits the trailing edge regulating means 38. This alignment operation rotates the left and right alignment motors M1, M2 by the same amount in opposite directions (approaching directions).

[0056] Then, the sheets carried into the processing tray 37 are positioned based on the sheet center and stacked in a bundle. By repeating this sheet carrying-in operation and aligning operation, the sheets are collated and accumulated in a bundle on the processing tray 37. At this time, sheets of different sizes are positioned based on the center. Furthermore, in the case of "corner binding", the sheets are carried onto the processing tray 37, and the aligning operation starts when the sheet edge hits the trailing edge regulating means 38. This aligning operation causes the amount of movement of the aligning plate on the binding position side and the aligning plate on the opposite side of the binding position to differ. Then, a preset The amount of movement is set so that the sheet corner is positioned at the specified binding position.

[0057] When performing the "stapleless binding process" (described later) on the sheet corners, the sheets discharged onto the processing tray with the center reference are center-aligned by side alignment members 39F and 39R, and are positioned and stacked in a stack with the sheet center as the reference. After the predetermined number of sheets to be stapled has been stacked, the sheet stack is sandwiched between side alignment members 39F and 39R and moves toward side alignment member 39R, and the stack is moved to the stapleless binding position.

[0058] Furthermore, when performing stapleless binding on sheets larger than a predetermined size and containing more than a predetermined number of sheets, side alignment members 39F and 39R center-align the sheets discharged onto the processing tray. Once the sheets are positioned based on the sheet centers and stacked into a bundle of the predetermined number, the bundle is moved to the stapleless binding position while still sandwiched between side alignment members 39F and 39R. Then, leaving side alignment member 39R in the same position as the bundle, side alignment member 39F returns to the sheet receiving position to receive the next sheet. When a sheet emerges onto the processing tray, side alignment member 39F is shifted toward side alignment member 39R. As a result, sheets exceeding the predetermined number (sheets discharged after the bundle shift operation) are moved one by one to the stapleless binding position.

[0059] [Binding processing mechanism] The processing tray 37 is provided with binding mechanisms 47 and 60 that bind the sheet stack accumulated on the paper loading surface 37a. The processing tray 37 is positioned to a predetermined binding position on the paper loading surface 37a by a positioning mechanism (sheet edge regulating means 38 and side edge aligning means 39). The binding mechanisms 47 and 51 are configured so that a first binding unit 47 (first binding means; hereinafter the same as "staple unit") that staples the sheet stack, and a second binding unit 51 (second binding means; hereinafter the same as "eco binding unit") that binds the sheet stack without staples are selectively positioned at the binding positions.

[0060] As shown in Figure 2, the processing tray 37 is provided with binding processing mechanisms 47, 51 that bind the rear end of the sheets transported through the paper discharge port 35. As shown in Figure 4, this binding mechanism is composed of a staple unit (first binding unit) 47 and an eco-binding unit (second binding unit) 51 that can be moved along the rear end of the paper loading surface 37a of the processing tray 37.

[0061] 4 shows a staple unit (first binding unit) 47 and an eco-binding unit (second binding unit) 51 arranged on a processing tray. In the illustrated device, a binding position Cp1 is set at the sheet corner located on the left side of the drawing. The first binding unit 47 and the second binding unit 51 move reciprocally to this binding position Cp1.

[0062] Therefore, the first binding unit 47 moves at a predetermined stroke SL1 along the first running rail 53 and the second running rail 54 formed on the device frame 27b, and similarly, the second binding unit 51 is arranged to move at a stroke SL2 along the first guide rod 56a and the second guide rod 56b (see Figure 10) arranged on the device frame 57.

[0063] 5 shows sheets fed into the processing tray 37 and the movement strokes of the first and second binding units 47, 51. Sheets of different sizes, from the largest size sheet to the smallest size sheet, are fed into the processing tray 37 with the center as the reference. A pair of left and right side edge alignment members 39F, 39R align these sheets (so that sheets of different sizes are aligned) with the binding side edge of the sheet (the left edge in the illustration) as the reference. For this reason, the left and right alignment members 39F, 39R are connected to different drive motors M1, M2, respectively, and a control means 95 (described later) sets the movement amount of the left and right alignment members 39F, 39R according to the sheet size.

[0064] In addition, the control means 95 described later aligns the sheets based on the center reference in the binding process other than the binding process of the sheet corners, for example, in the multi-binding mode described later. In this case, the left and right alignment members 39F, 39R position the sheets at the binding position by moving the same amount from the standby position toward the sheet center.

[0065] 5, the first binding unit 47 moves in a first stroke SL1 between the standby position Wp1 (first standby position) and the binding position Cp1, and the second binding unit 51 moves in a second stroke SL2 between the standby position Wp2 (second standby position) and the binding position Cp1. In other words, the first binding unit 47 reciprocates between the standby position Wp1 and the binding position Cp1 along traveling rails 53, 54 (guide grooves, guide rods, etc.), and the second binding unit 51 reciprocates between the standby position Wp2 and the binding position Cp1 along guide rods 56a, 56b (which may be guide grooves).

[0066] The binding position Cp1 is set at a sheet corner (hereinafter referred to as the "set binding position"), and the first standby position Wp1 and the second standby position Wp2 are set so that the following relationship holds with respect to this position. (1) The first standby position Wp1 and the second standby position Wp2 are set to be located on opposite sides of the set binding position Cp1. (2) The first waiting position Wp1 is set either outside the maximum size sheet to be bound on the processing tray, or at the binding processing position on the processing tray farthest from the set binding position Cp1 (the multi-binding position Ma or the manual binding position Mp; the most remote binding position, which will be described later). (3) The second standby position Wp2 is set outside the sheet side edge that aligns with the set binding position (outside the sheet placement area of ​​the paper placement surface). (4) The first stroke length SL1 between the first standby position Wp1 and the set binding position Cp1 is set to be larger (longer) than the second stroke length SL2 between the second standby position Wp2 and the set binding position Cp1.

[0067] In this way, by setting the first standby position Wp1 and the second standby position Wp2 on the opposite side of the set binding position Cp1, when one unit approaches, the other unit moves away (reciprocal retraction approaching operation). Also, by setting SL1 > SL2, it is possible to set the binding processing position of the first binding unit 47 (multiple binding position Ma, described later) relatively freely. In contrast, the second binding unit 51 performs binding processing only at a preset binding position. This allows the total movement stroke length of the first and second binding units 47, 51 to be set short, thereby making it possible to miniaturize the device.

[0068] The control means 95, which will be described later, reciprocally moves the first and second binding units 47 and 51 to the standby position Wp2 and the standby position Wp1, respectively, when the first and second binding units 47 and 51 are at the set binding position Cp1 and Cp1, respectively. In other words, when one binding unit binds sheets, the position of the other binding unit is set to the outside (outside) of the sheet carry-in area for sheets carried into the processing tray 37 (sheets to be bound by one binding unit), i.e., outside the sheets on the processing tray 37 (a state in which the sheets to be bound by one binding unit have not entered the opening of the other binding unit). With this configuration, when the first binding unit 47 performs binding processing, the opening of the second binding unit 51 does not interfere with the sheet stack, causing the sheet stack to lose its posture. Furthermore, the number of sheets to be bound by the first binding unit 47 is not limited by the binding processing capability of the second binding unit 51, which has a low processing capability.

[0069] The reciprocal positional movement of the first and second binding units 47, 51 is achieved by either (1) varying the amount of rotation of each of the independent drive motors according to the movement stroke, or (2) varying the amount of movement of the first binding unit 47 and the second binding unit 51 using the same drive source.

[0070] 6 shows a configuration in which the first binding unit 47 and the second binding unit 51 are moved by different amounts using the same drive source. A pair of left and right pulleys 58a, 58b are arranged on the device frame 27b along the movement area of ​​the first unit (left and right direction in FIG. 6), a timing belt 59 (toothed belt) is stretched between the two pulleys, and a drive motor M3 (stepping motor) is connected to one of the pulleys, 58a.

[0071] A transmission pinion 75 is connected to the other pulley 58b via a differential means (transmission means) 74, and this pinion is engaged with a rack 76 fixed to the frame of the second binding unit 51. The differential means 74 is configured by a gear mechanism (first embodiment described below) with a transmission ratio that matches the stroke difference between the first and second strokes SL1 and SL2, a slip clutch mechanism (second embodiment described below), or a combination of both of these mechanisms.

[0072] [First embodiment of differential means] FIG. 7 shows a first embodiment of the differential means 74, and the transmission mechanism shown in a perspective configuration in FIG. 6 has a transmission ratio that is different so that when the drive motor M3 rotates a predetermined amount, the first binding unit 47 moves back and forth linearly in a first stroke SL1 and the second binding unit 51 moves back and forth linearly in a second stroke SL2.

[0073] For example, in the illustrated device, the second stroke length SL2 is set to one-fifth of the first stroke length SL1, so the gear ratio of gear G1 connected to drive motor M3 is set to five times the gear ratio of gear G3 meshing with the rack via gear G2. In Figure 7(b), a transmission gear G1 is provided on pulley (driven pulley) 58b connected to drive motor M3, and gear G2, which is driven by this gear, is connected to rack 76 so as to rotate coaxially and integrally with the meshed gear G3. The gear ratio of gear G1 to gears G2 and G3 is set to match the stroke ratio of the first and second stroke lengths SL1 and SL2.

[0074] Therefore, when the drive motor M3 is rotated by a predetermined amount, the first binding unit 47 moves through a first stroke SL1, and at the same time, the second binding unit moves through a second stroke SL2. The directions of these movements are set to be the same.

[0075] [Second embodiment of differential means] As shown in the perspective configuration in Fig. 6, the timing belt 59 of the first binding unit 47 is connected to the drive motor M3. At this time, as described above, the movement stroke SL1 of the first binding unit 47 is set to be longer than the movement stroke SL2 of the second binding unit 51. Therefore, in the differential means 77 shown in Fig. 8, a slip clutch means 78 is disposed in the transmission means of the second binding unit 51, which has a shorter movement distance.

[0076] 8(a) shows an example of a slip clutch mechanism. A transmission gear G4 is provided integrally with the pulley shaft 58x of the timing belt 59 that is connected to the drive motor M3 and reciprocates the first binding unit 47, and a gear G5 that meshes with this gear is attached integrally to a transmission rotation shaft 79. A transmission pinion G6 is rotatably fitted loosely on the outer periphery of the transmission rotation shaft 79. A rack 76 fixed to the second binding unit 51 is connected to this transmission pinion G6 so as to mesh with it.

[0077] A clutch spring 73 is provided between the transmission rotating shaft 79 connected to the drive motor M3 and the transmission pinion G6 loosely fitted to this rotating shaft so that a sliding motion occurs between the transmission rotating shaft 79 and the transmission pinion G6 when the load torque transmitted to the transmission pinion G6 exceeds a predetermined value.

[0078] As shown in Figures 8(b), (c), and (d), the free ends 73a and 73b of the clutch spring 73 are adapted to engage with protrusions G6a and G6b provided on the transmission pinion G6 side. The clutch spring 73 and the transmission rotation shaft 79 are frictionally engaged. When the load torque of the transmission pinion G6 exceeds a predetermined value, the spring relaxes, causing slippage between the transmission rotation shaft 79 and the transmission pinion G6, and when the load torque is equal to or less than the predetermined value, rotation is transmitted in the state shown in Figure 8(b). When the load torque acting on the second binding unit 51 exceeds the predetermined value, slippage occurs between the transmission rotation shaft 79 and the transmission pinion G6 during rotation in the direction of the arrows in Figures 8(c) and (d).

[0079] In this configuration, when the first binding unit 47 moves from the set binding position Cp1 to the standby position Wp1 due to the rotation of the drive motor M3, the clutch spring 73 moves the second binding unit 51 from the standby position Wp2 toward the set binding position Cp1 in conjunction with the second binding unit 51 in the state shown in FIG. 8(b). When the second binding unit 51 reaches the set binding position Cp1 and hits a locking stopper (not shown), a load torque close to infinity acts on the transmission pinion G6. In excess of this load torque, the clutch spring 73 forms a gap with the transmission rotation shaft 79 and performs a sliding movement. Then, with the subsequent rotation of the drive motor M3, the first binding unit 47 moves toward the standby position Wp1.

[0080] The transmission rotation and sliding rotation by the clutch spring 73 also perform the same interlocking action when the first binding unit 47 moves from the standby position Wp1 to the set binding position Cp1 (reverse rotation of the motor). In this way, the first binding unit 47 reciprocates through the first stroke SL1 with the forward and reverse rotation of the drive motor M3, and at the initial stage of its movement, the second binding unit 51 is interlocked with the first binding unit 47 to reciprocate through the second stroke SL2, after which the rotation of the drive motor M3 is transmitted only to the first binding unit 47.

[0081] [Staple unit moving mechanism] As shown in Fig. 3, the staple unit 47 is mounted on a device frame (chassis frame) 27b so as to be movable at a predetermined stroke. A first traveling rail 53 and a second traveling rail 54 are arranged on the device frame 27b. A traveling rail surface 53x is formed on the first traveling rail 53, and a traveling cam surface 54x is formed on the second traveling rail 54. The traveling rail surface 53x and the traveling cam surface 54x cooperate with each other to support the staple unit 47 (hereinafter referred to as "moving unit" in this section) so as to be reciprocable at a predetermined stroke, and at the same time, control its angular posture.

[0082] The first traveling rail 53 and the second traveling rail 54 are formed with rail surfaces 53x and traveling cam surfaces 54x so as to reciprocate within the movement range of the moving unit (see FIG. 5). A timing belt 59 connected to a drive motor (travel motor) M3 is fixed to the moving unit 47 (stapling unit). This timing belt 59 is wound around a pair of pulleys 58a, 58b journaled on the device frame 27b, and the drive motor M3 is connected to one of the pulleys. Therefore, the forward and reverse rotation of the drive motor M3 causes the staple unit 47 to reciprocate at a stroke SL1.

[0083] The traveling rail surface 53x and the traveling cam surface 54x are spaced apart from each other by a parallel interval (span I1), a narrow swivel interval (span I2), and an even narrower swivel interval (span I). The relationship is span I1 > span I2 > span I3. In span I1, the unit is parallel to the rear edge of the seat; in span I2, the unit is tilted to the left or right; and in span I3, the unit is tilted even further.

[0084] The moving unit 47 engages with the first and second traveling rails 53, 54 as follows. As shown in Fig. 3, the moving unit 47 is provided with first rolling rollers 83 (rail fitting members) that engage with the traveling rail surfaces 53x and second rolling rollers 84 (cam follower members) that engage with the traveling cam surfaces 54x. The moving unit 47 also has sliding rollers 85 (the illustrated one has ball-shaped sliding rollers 85a, 85b formed in two locations) that engage with the support surface of the frame 27b. The moving unit 47 also has guide rollers 86 that engage with the bottom surface of the bottom frame 27b, preventing the moving unit 47 from floating up from the bottom frame 27b.

[0085] With the above configuration, the moving unit 47 is movably supported on the bottom frame 27b by the sliding rollers 85 and the guide rollers 86. At the same time, the first rolling rollers 83 and the second rolling rollers 84 rotate along the traveling rail surfaces 53x and the traveling cam surfaces 54x, respectively, and travel along the rail surfaces 53x and the cam surfaces 54x.

[0086] Therefore, the distance between the traveling rail surface 53x and the cam surface 54x is a parallel distance portion (span I1) formed at the multi-binding positions Ma1 and Ma2 and the manual binding position Mp. In this span I1, the moving unit 47 is held in a position perpendicular to the sheet edge without swinging, as shown in Figure 4. Therefore, at the multi-binding position and the manual binding position, the sheet stack is bound with staples parallel to the sheet edge.

[0087] Furthermore, the distance between the traveling rail surface 53x and the cam surface 54x is a swing distance (span I2) formed at the right corner binding position Cp2 and the left corner binding position Cp1. As shown in FIG. 4, the moving unit 47 is held in a right inclined angle posture (for example, inclined 45 degrees to the right) and a left inclined angle posture (for example, inclined 45 degrees to the left).

[0088] Furthermore, the distance between the running rail surface 53x and the cam surface 54x is a swing interval (span I3) that is formed at the staple loading position. This span I3 is formed to be shorter than span I2, and in this state the moving unit 47 is held in a right-tilted angular position (for example, tilted at 60 degrees) as shown in Figure 4. The reason for changing the angle of the moving unit 47 at the staple loading position is to align the unit position with the angular direction in which the staple cartridge 52 is attached to the unit, and the angle is set in relation to the open / close cover placed on the exterior casing.

[0089] When the angular posture of the moving unit is deflected by the above-described traveling rail surface 53x and traveling cam surface 54x, it is preferable to provide a second traveling cam surface to shorten the travel length, or to provide a stopper cam surface and deflect the angle in cooperation with the traveling cam surface, in terms of compactness of the layout.

[0090] The stopper cam surfaces shown in the figure will now be described. As shown in Figure 4, the bottom frame 27b has stopper surfaces 27c and 27d arranged at the positions shown in the figure that engage with part of the moving unit (the sliding roller 85 shown) in order to change the unit posture at the right-corner binding position Cp2 on the front side of the device and at the manual binding position Mp. This makes it necessary to correct the tilt of the unit that is tilted at the staple loading position at the manual binding position Mp, but changing the angle using only the cam surface and rail surface mentioned above results in a lengthy movement stroke.

[0091] Therefore, when the moving unit 47 is advanced toward the manual binding side while being locked by the stopper surface 27c, the unit returns from the tilted state to its original state. Also, when the moving unit 47 is returned in the opposite direction from the manual binding position, the stopper surface 27d (forcibly) tilts the unit toward the corner binding position.

[0092] [Configuration of the staple unit] The configuration of the above-mentioned staple unit (first binding unit) will be described with reference to Fig. 9(a). The staple unit 47 is configured as a unit separate from the sheet post-processing device B. A box-shaped unit frame 47a, a drive cam 47d pivotally supported on the frame, and a drive motor M4 that rotates the drive cam are mounted on the unit frame 47a.

[0093] A staple head 47b and an anvil member 47c are disposed on the drive cam 47d so as to face each other at the stapling position, and the staple head 47b is moved up and down by a biasing spring (not shown) on the drive cam 47d from an upper standby position to a lower staple position (anvil member). A staple cartridge 52 is detachably mounted on the unit frame.

[0094] The staple cartridge 52 stores straight blank staples, and a staple feed mechanism supplies the staples to the staple head 47b. The staple head 47b contains a former that bends the straight staples into a U-shape and a driver that presses the bent staples into a sheet stack. This configuration causes the drive motor M4 to rotate the drive cam 47d, which stores energy in the spring. When the rotation angle reaches a predetermined angle, the staple head 47b swiftly descends toward the anvil member 47c. This action bends the staple into a U-shape, and the driver then inserts the staples into the sheet stack. The tip of the staple is then bent by the anvil member 47c, resulting in a staple binding.

[0095] A staple feed mechanism is built in between the staple cartridge 52 and the staple head 47b, and a sensor (empty sensor) is disposed in this staple feed section to detect the absence of staples.Also, a cartridge sensor (not shown) is disposed in the unit frame 47a to detect whether the staple cartridge 52 is inserted or not.

[0096] The illustrated staple cartridge 52 employs a structure in which staples connected in a strip-like shape are stored in layers in a box-shaped cartridge, and a structure in which the staples are stored in a roll-like shape. The unit frame 47a is also provided with circuits for controlling the above-mentioned sensors and a circuit board for controlling the drive motor M4, and is designed to issue a warning signal when the staple cartridge 52 is not stored or when the staples are empty. The staple control circuit is also designed to control the drive motor M4 to execute the stapling operation in response to a staple signal, and to issue an "operation end signal" when the staple head moves from the standby position to the anvil position and then returns to the standby position.

[0097] [Configuration of staple-free binding unit (pressure binding means)] The configuration of the second binding unit (staple-free binding unit) 51 described above will be explained with reference to FIG. 9(b). Staple-free binding devices that bind a sheet stack without using metal staples include a press-bind binding device that binds the sheets by clamping the sheets from both sides with pressure members having interlocking concave and convex surfaces, a slit-shaped cut in the sheet stack and folding the sheets together to bind them (a cut-and-fold binding device; see JP 2011-256008 A), and a resin-string binding device that binds the sheets together. These binding methods are known as eco-friendly binding methods because they use a sheet stack without using metal staples. The press-bind mechanism will be explained below as an example.

[0098] The press bind mechanism forms uneven surfaces on pressure surfaces 51b and 51c, which can be pressed against and separated from each other, and presses the sheet stack from both sides, deforming the sheets and binding them. Figure 9(b) shows the press bind unit 51, in which a movable frame member 51d is pivotally supported on a base frame member 51a, and both frames are pivoted by a support shaft 51x so that they can be pressed against and separated from each other. A follower roller 60 is disposed on the movable frame member 51d, and this follower roller is engaged with a drive cam 68 disposed on the base frame member 51a.

[0099] A drive motor M5 arranged on the base frame member 51a is connected to the drive cam 68 via a reduction mechanism, and the rotation of the motor causes the drive cam 68 to rotate, and its cam surface (the one shown is an eccentric cam) swings the movable frame member 51d.

[0100] The base frame member 51a has a lower pressure surface 51c, and the movable frame member 51d has an upper member pressure surface 51b, which are positioned to face each other. A biasing spring (not shown) is disposed between the base frame member 51a and the movable frame member 51d, and biases the two pressure surfaces in directions that separate them.

[0101] As shown in the enlarged view of Figure 8(b), the upper pressure surface 51b and the lower pressure surface 51c have protrusions on one side and matching recesses on the other side. These protrusions and recesses are formed in the shape of ribs of a predetermined length. Therefore, the sheet stack sandwiched between the upper pressure surface 51b and the lower pressure surface 51c is deformed into a corrugated shape and tightly adheres to each other. A position sensor (not shown) is disposed on the base frame member 51a (unit frame) and is configured to detect whether the upper and lower pressure surfaces 51b, 51c are in the pressure position or the separation position.

[0102] The press bind unit (eco-binding unit; second binding unit) 51 configured in this manner is movably arranged on the first and second guide rods 56a, 56b (which may be grooves) arranged on the device frame 57, and as described above, moves back and forth between the set binding position Cp1 of the sheets accumulated on the processing tray 37 and the second waiting position Wp.

[0103] [Sheet bundle discharge mechanism] The processing tray 37 is provided with a sheet bundle discharge mechanism that discharges the bound sheet bundle toward the downstream first tray 49. Known means for transporting the sheet bundle downstream include a method using a pair of rollers (discharge means) that press against each other, and a conveyor means that pushes out the trailing ends of the sheets with a push-out member that moves from upstream to downstream along the tray surface. The illustrated device employs both of these means.

[0104] 10 shows the sheet bundle discharge mechanism, in which the conveyor means is made up of the push-out protrusion 38 that transfers the sheets from the binding position (processing position) located upstream along the processing tray 37 to the stack tray (first tray) 49 downstream, the conveyor belt 38v that moves the push-out protrusion, and its drive motor M6. The processing tray 37 has a driven roller 48 arranged at its discharge outlet (the boundary between the paper loading surface 37a and the first tray 49), and the lift roller 41 that presses against the driven roller is arranged opposite to it in the configuration described above, and the driven roller 48 and the lift roller 41 make up the discharge roller means.

[0105] Therefore, the processing tray 37 is provided with conveyor means 38, 38v that transport the sheet bundle by pushing it from the upstream side to the downstream side, and discharge roller means 48, 41 that nip and discharge the sheet bundle. FIG. 10(a) shows the state in which the sheet bundle is positioned at the binding position on the processing tray, with the conveyor means 38, 38v and discharge roller means 48, 41 in operation. FIG. 10(b) shows the state in which the sheet bundle is being transported from the processing position to the downstream side, with the sheet bundle being sent downstream by the movement of the push-out projection 38 and the rotation of the discharge roller means 48, 41. FIG. 10(c) shows the state immediately before the sheet bundle is discharged to the first tray 49 on the downstream side, with the sheet bundle being gradually (at a low speed) sent downstream on the processing tray by the rotation of the discharge roller means 48, 41. At this time, the push-out projection 38 waits in the illustrated position and returns (rearwards) to its initial position.

[0106] [Configuration of folding roll means] The folding position Y, which is disposed downstream of the second processing section B2, is provided with a folding roll means 64 for folding the sheet bundle together and a folding blade 65 for inserting the sheet bundle into the nip position of the folding roll means.

[0107] The pair of folding rolls 64a, 64b are made of a material with a relatively large coefficient of friction, such as a rubber roller, in order to transfer the sheet in the rotational direction while folding it using a soft material such as rubber, and may be formed by lining with a rubber material.

[0108] The pair of folding rolls 64a, 64b are located on the curved or bent protruding side of a guide member 66, and folding blades 65 having knife edges are provided at positions opposite to each other across the sheet stack supported by the guide member.

[0109] [Sheet stack folding finishing mode] In this mode, image forming apparatus A forms an image on a sheet, which is then finished into a booklet by sheet post-processing apparatus B. The sheet sent to sheet carry-in path 28 is guided to discharge rollers 36, where control CPU 95 stops discharge rollers 36 when the trailing edge of the sheet passes a path switching piece, based on a signal detected by sheet sensor S1. Then discharge rollers 36 are reversed. This reverses the conveying direction of the sheet that has entered sheet carry-in path 28, and the sheet is guided from the path switching piece to second discharge path 32. The sheet is then guided to guide member 66 by conveyance rollers arranged on this path.

[0110] At the timing when the sheet is conveyed from the second discharge path 32 to the guide member 66, the control CPU 95 moves the regulating stopper 67 to a position where the sheet is supported by the guide member 66 in its entirety.

[0111] Therefore, when the control CPU 95 receives a job end signal, it moves the regulating stopper 67 and positions and sets the center of the sheets at the binding position.The control CPU 95 then operates the saddle stitching staple device 63 and staples the sheets at one or more positions in the center.When a signal indicating this operation is completed is received, the control CPU 95 moves the regulating stopper 67 and positions and sets the center of the sheets at the folding position Y.After folding the sheet bundle, the sheet bundle is conveyed to the second stack tray 61.

[0112] [Control configuration explanation] The control configuration of the image forming system in Fig. 1 will be described with reference to Fig. 11. The image forming system shown in Fig. 11 includes a control unit 90 of image forming apparatus A (hereinafter referred to as "main body control unit") and a control unit 95 of sheet post-processing apparatus B (hereinafter referred to as "binding process control unit"). The main body control unit 90 includes a print control unit 91, a paper feed control unit 92, and an input unit 93 (control panel).

[0113] Then, the "image formation mode" and "post-processing mode" are set from the input unit 93 (control panel). The image formation mode includes mode settings such as color / monochrome printing, double-sided / single-sided printing, and image formation conditions such as sheet size, sheet paper quality, number of printouts, and enlarged / reduced printing. The "post-processing mode" is set to, for example, "printout mode," "staple binding mode," "eco binding mode," or "jog sorting mode." The illustrated device is also provided with a "manual binding mode," which performs the binding process for a sheet stack offline, separate from the main body control unit 90 of image forming device A.

[0114] Furthermore, the main body control unit 90 transfers data such as the post-processing mode, the number of sheets, the number of copies, and the thickness of the sheets on which images are formed to the binding process control unit 95. At the same time, the main body control unit 90 transfers a job end signal to the binding process control unit 75 each time image formation is completed.

[0115] To explain the post-processing mode, in the "printout mode," sheets from the paper discharge port 35 are stored in the stack tray 49 via the processing tray 37 without being bound. In this case, the sheets are stacked one on top of the other on the processing tray 37, and the stacked sheet bundle is conveyed to the stack tray 49 in response to a jog end signal from the main body control unit 90.

[0116] In the "staple binding processing mode," sheets from the paper discharge outlet 35 are accumulated and collated on the processing tray, and after this sheet bundle is bound, it is stored in the stack tray 49. In this case, the operator specifies that the sheets on which images are to be formed are, in principle, of the same thickness and size. This staple binding processing mode is specified by selecting one of "multi-binding," "right corner binding," or "left corner binding." The binding positions for each mode are as described above.

[0117] In the "jog sorting mode," sheets on which images are formed by image forming apparatus A are separated into a group in which they are offset and accumulated, and a group in which they are accumulated without being offset, and the stack tray alternately stacks the offset sheet bundles and the non-offset sheet bundles.

[0118] [Manual Binding Mode] The exterior casing is provided with a manual set section on the front side of the device where the operator sets the sheet stack to be bound. A sensor is disposed on the set surface of this manual set section to detect the set sheet stack, and a binding process control section 95 (described later) moves the stapler unit 47 to the manual binding position in response to a signal from this sensor. When the operator presses the activation switch, the binding process is executed.

[0119] Therefore, this manual binding mode is controlled offline by the binding process control unit 95 and the main body control unit 90. However, when the manual binding mode and the staple binding mode are executed simultaneously, the mode is set so that one of them takes priority.

[0120] [Binding processing control unit (control means)] The binding process control unit 95 operates the sheet post-processing device B in accordance with the post-processing mode set by the image formation control unit 90. The illustrated binding process control unit 95 is composed of a control CPU (hereinafter simply referred to as control means). The control CPU 95 is connected to a ROM 96 and a RAM 97, and executes a sheet discharge operation (described later) using a control program stored in the ROM 96 and control data stored in the RAM 97. For this reason, the control CPU 95 is connected to the drive circuits of all the drive motors mentioned above, and controls the start, stop, and forward / reverse rotation of each motor.

[0121] [Paper ejection mode] The control unit (main body control unit) 90 of the image forming apparatus A sets the image forming conditions and also sets the post-processing (finishing) mode for the sheets on which the images have been formed. The illustrated apparatus is set to "staple binding mode," "eco binding mode," "jog sorting mode," "bookbinding finishing mode," "printout mode," "interrupt mode," and "manual binding mode." The operation of each mode will be explained below.

[0122] Fig. 12 is an explanatory diagram of the operation flow for stapling or eco-binding a sheet bundle accumulated on the processing tray 37 of the first processing unit B1 and storing the sheets in the downstream first tray 49. Fig. 13 is an explanatory diagram of the sheet discharge mode in which sheets are jogged and sorted into sets, and is an explanatory diagram of the operation flow for offsetting the sheets in a direction perpendicular to the sheet discharge direction by a jog mechanism (roller shift mechanism; not shown) of the third processing unit (sheet carry-in path) B3 and then storing the sheets in the downstream third tray 71. Fig. 14 is an explanatory diagram of the bookbinding processing sheet discharge mode in which sheets are bound in the second processing unit B2.

[0123] [Staple binding mode and eco binding mode in the first processing section] Explaining with reference to Fig. 12, the post-processing mode is set on the control panel 93 of the image forming apparatus A or the like (St01). The control means 95 of the sheet post-processing device moves the binding unit when staple binding processing is specified based on the post-processing mode setting information (St04). The control means 95 also moves the binding unit when eco-binding processing is denied (St05).

[0124] When performing staple binding processing, the first binding unit 47 is moved to the set binding position Cp1, and the second binding unit is moved to the second standby position Wp2. When this unit position is set as the home position, each unit checks whether it is at home or not before moving.

[0125] Next, image forming apparatus A forms an image and discharges the sheet (St07, St08). Sheet post-processing apparatus B accepts the image-formed sheet sent to the carry-in entrance 26 and transports it downstream (St09). At this time, if punching processing is specified (St10), control means 95 temporarily stops the sheet at the punching position (St11). Then, punch unit 50 moves in a direction perpendicular to the sheet discharge direction, detects the side edge of the sheet with a sensor, determines the predetermined punching position, and then stops punch unit 50 and performs the punching operation (St13).

[0126] When punching is not specified, the control means 95 accepts the sheets at the entrance and transports them to the path paper discharge outlet. The sheets are then transported to the processing tray 37 and positioned at a predetermined position by the positioning means (St15). The control means 95 stacks and stores the sheets sent to the paper discharge outlet 35 on the paper mounting surface of the processing tray 37 (St07 to St15). When the control means 95 receives a jog end signal from the image forming apparatus A (St16), it transmits a binding processing instruction signal to the first binding unit 47 or the second binding unit 51. The first binding unit 47 or the second binding unit 51 then executes the binding process (St17).

[0127] When the control means 95 receives a binding process completion signal from the first (or second) binding unit 47, 51, it stores the sheet bundle bound by the sheet bundle discharge means in the downstream first tray 49 (St18). Then, a paper surface level detection sensor (not shown) arranged in the first tray 49 detects the stack height, and if it exceeds a predetermined angle, it moves down the first tray 49 (St20). Next, the control means 95 determines whether or not there is a next job (St21) and completes the operation.

[0128] [Eco Binding Mode] The eco-binding mode operation will be described in detail below with reference to the flowchart of FIG. 13 showing the NS binding (eco-binding) operation.

[0129] [Explanation of Eco Binding Operation] The eco-binding process operation will be described with reference to the flowchart in Fig. 13 and the corresponding operation diagrams in Fig. 14 and subsequent figures. The control means 95 starts a crimp binding job when it receives a signal from the image forming unit A indicating that the crimp binding process mode has been selected. Based on a paper output start signal sent from the image forming apparatus main body or a leading edge detection signal from the sheet sensor S1 (St22), before at least the first sheet to be crimp bound is discharged to the processing tray 37, the paddle rotor 42 is positioned at a standby position, and the side alignment means 39F and 39R are positioned at standby positions wider than the width of the discharged sheet (positioned outward in the width direction from the sheet width) (St23).

[0130] Next, the control means 95 lowers the paddle rotor 42 from the upper standby position to the operating position at the timing when the rear end of the sheet passes the paper discharge roller 36 (St24, FIG. 14(a)), and simultaneously lowers the knurled rotor 46 (knurled belt 46) from the standby position above the paper loading surface to the operating position above the paper loading surface (St25). At this time, both the paddle rotor 42 and the knurled rotor 46 are rotating in the direction opposite to the paper discharge direction.

[0131] The control means 95 raises the paddle rotor 42 from the operating position to the standby position when a predetermined time has elapsed (the estimated time when the trailing edge of the sheet will reach the position where it will be picked up by the knurled rotor 46). The control means 95 also raises the knurled rotor 46 slightly after a predetermined time has elapsed (the estimated time when the leading edge of the sheet will reach the trailing edge regulating member). The amount of lift of the knurled rotor 46 is preset and set based on experimental values ​​so as to reduce the pressing force on the sheet. As a result, the trailing edge of the sheet in the conveyance direction comes into contact with the sheet regulating means 38 (FIG. 14(b)).

[0132] Next, the control means 95 varies the control depending on the size of the conveyed sheet (St27). If the size of the sheet discharged to the processing tray 37 is small (A4 or letter), the first sheet is centered by the side alignment members 39F and 39R (St26, Figure 14(c)). In order to convey the second sheet to the processing tray 37, the side alignment members 39F and 39R are moved to the sheet receiving position (St29, Figure 14(d)).

[0133] In this embodiment, the pressure binding device is set to a maximum number of sheets to be bound of 10, and the upper limit of the number of sheets that can be shifted in a small-size bundle is 10. Therefore, it detects whether the set number of sheets n to be bound of 10 or less has been reached (St28) (this may also be recognized from the number information received from the image forming device main body), and repeats the above-mentioned sheet transport and center alignment until this number is reached (Figures 15(e), (f) St24 to St29).

[0134] Next, the control means 95 moves the knurled rotor 46 to a standby position (a position where it does not touch the sheet stack) (St30), and then moves it to the rear side while the sheet stack is clamped between the side alignment members 39F and 39R, and moves the stack to the crimp binding position (St31, Figure 15(g)).

[0135] The sheet stack moved to the pressure binding position is aligned in the width direction by side alignment member 39F at pressure binding position Ep (St32), and then knurled rotor 46 is lowered from the standby position above the paper loading surface to an operating position above the paper loading surface (St33). At this time, knurled rotor 46 is rotated in the opposite direction to the paper discharge direction and positioned (FIG. 16(h)), and then pressure binding processing is performed by pressure binding means 51 (St34, FIG. 16(i)). The bound sheet stack is then moved downstream in the sheet conveyance direction to complete the sheet discharge operation (St35, FIG. 16(j)). At this time, side alignment members 39F and 39R remain in the alignment position or move slightly away from the sheets.

[0136] Next, we will explain the case where the size of the sheets discharged to the processing tray 37 is large size (A3 or ledger) and the set number of sheets to be bound is less than the maximum number of sheets that can be shifted in a bundle for large size (in this embodiment, up to 5 sheets for large size) (St36).

[0137] The control means 95 uses the side alignment members 39F and 39R to center the first sheet discharged onto the processing tray 37 (St26, FIG. 17(a)). To transport the second sheet to the processing tray 37, the control means 95 moves the side alignment members 39F and 39R to the sheet receiving position (St29, FIG. 17(b)).

[0138] In this embodiment, the crimp binding device is set to a maximum number of sheets to be bound of 10, but because the driving force of the alignment plate limits the number of sheets that can be shifted in a large-size bundle to 10 or less (5 sheets), it detects whether the set number of sheets to be bound, n, of 5 or less, has been reached (St28), and repeats the above-described sheet conveyance and center alignment until the number is reached (St24 to St29). Subsequent operations are the same as those for the small-size bundle described above (St30 to St35, Figures 17(c) to (d), and Figures 18(e) to (g)).

[0139] In this embodiment, the set number of sheets when processing large size is 5, but this is set based on a value that is about half the load on the device (on the alignment plate) when shifting a stack of 10 small size sheets, and it is also possible to set a table with a more detailed upper limit number of sheets depending on the size and basis weight, and to vary the operation. Also, if the number of sheets stacked in the center exceeds the number that can be crimp-stitched, the binding operation is canceled and the sheets are discharged.

[0140] Next, a case where the size of the sheets discharged to the processing tray 37 is large size and the set number of sheets to be bound exceeds the upper limit number of sheets that can be shifted in a bundle for large size (St37) will be described.

[0141] The control means 95 uses the side alignment members 39F and 39R to center the first sheet discharged onto the processing tray 37 (St26, FIG. 19(a)). To transport the second sheet to the processing tray 37, the control means 95 moves the side alignment members 39F and 39R to the sheet receiving position (St29, FIG. 19(d)).

[0142] As described above, the maximum number of sheets that can be bound by the crimp binding device in this embodiment is 10, but the upper limit for the number of sheets that can be shifted in the case of large size sheets is 5. When forming a sheet bundle, it is advantageous in terms of sheet alignment to form the bundle with center alignment as much as possible and then shift the bundle, so the sheet conveyance and center alignment are repeated in the same manner as the control content described above until the number of sheets reaches 5 (Steps 24 to 29, Figures 19(c) and 19(d)).

[0143] Next, the control means 95 moves the knurled rotor 46 to the weak nip position (a position between the standby position and the pick-up position, where the knurled rotor barely touches the sheets) (St38, FIG. 20(e)), moves the side alignment members 39F, 39R to the rear side with the sheet stack sandwiched between them, and moves the stack to the pressure binding position (St39, FIG. 20(f)). Then, after the sheet stack has been moved to the pressure binding position, the side alignment member 39F is moved toward the side alignment member 39R at the pressure binding position Ep to align it in the width direction (St40), and then, with the side alignment member 39R still positioned at the pressure binding position Ep, the side alignment member 39F is moved to the sheet receiving position to receive the next sheet (St41, FIG. 20(g)). Each time the next sheet is conveyed to the processing tray 37 (St42, FIG. 20(h)), it is moved to the pressure binding position by the side alignment member 39F (shift one sheet) (St44, FIG. 21(i)). At this time, the knurled rotor 46 is moved to the weak nip position described above (St43, FIG. 20(e)). Then, it is detected whether the set number of sheets to be bound has reached the nth sheet (nth sheet: n≦10 sheets) (St45), and conveyance to the processing tray and movement to the pressure binding position are repeated for each sheet until the nth sheet is reached (St41 to St45).

[0144] Each sheet is moved to the pressure binding position, and it is confirmed whether the number of sheets is within the upper limit (10 sheets in this embodiment) that can be pressure bound (St46) (the cancellation operation will be explained later).

[0145] Next, the control means 95 moves the side alignment member 39F to a position away from the sheet stack that has been moved to the pressure binding position up to the set number n of sheets to be bound (St47), moves the knurled rotor 46 from the standby position above the paper loading surface to an operating position (screw position) on the paper loading surface to screw the sheets (St48), and moves the knurled rotor 46 to the standby position (a position where it does not touch the sheet stack) (St49), performs a widthwise alignment operation with the side alignment members 39F and 39R at the pressure binding position Ep (St32), and then lowers the knurled rotor 46 from the standby position above the paper loading surface to the operating position (screw position) on the paper loading surface (St33). At this time, both the paddle rotor 42 and the knurled rotor 46 are rotated in the opposite direction to the paper discharge direction (the direction of feeding) and positioned (Figure 21(k)), and then the pressure binding process is performed using the pressure binding means 51 (St34, Figure 21(k)), and the bound sheet stack is moved downstream in the sheet transport direction to complete the sheet discharge operation (St35, Figure 22(l)).

[0146] The upper limit number of sheets that can be shifted in a bundle may be replaced with the total count number α of the count number set for each sheet size, making it possible to perform optimal control with good alignment when binding a mixture of sheets of different sizes with the same width (small size: A4 landscape, large size: A3 portrait). This is done by setting the count number for one small size sheet to 60 and the count number for one large size sheet to 120, and when the total count number of sheets discharged to the processing tray 37 reaches the predetermined total count number of 600, the bundle is moved to the pressure binding position by the side alignment members 39F, 39R, and thereafter, control (from St38) is performed when the above-mentioned predetermined number of sheets for the large size is exceeded. For example, in the case of a mixed load of sheets of the same width, such as nine A4 (small size) sheets and one A3 (large size), the count value of the nine A4 sheets is 540, and if the paper information for the next sheet is A3, 120 is added to the count value for a total of 660, so the stack of sheets is shifted when this tenth A3 sheet is accepted and fed in, or, when information that the next sheet is A3 is received, it is determined that the count value will exceed 600, so the stack of A4 (9-sheet stack) that has already been fed into the processing tray 37 is shifted, and then the A3 (only one sheet) is discharged onto the processing tray 37 and shifted.

[0147] Although this embodiment has been described in the eco binding mode, it can also be applied to staple binding and other post-processing as long as it is a mode in which sheets are offset, not limited to the eco binding mode. Also, regarding the shift operation after the number of sheets that can be shifted has been exceeded, the operation of shifting one sheet at a time has been described, but depending on the driving force of the alignment plate and the tilt angle and shape of the processing tray, it is also possible to shift within a range not exceeding five sheets, for example, every two sheets.

[0148] [Action / Cancel action when the number of sheets that can be bound with pressure binding exceeds] In St46 of the flowchart in FIG. 13, if the number of sheets that can be crimped and bound is exceeded and further sheets are discharged to form the same bundle (the process proceeds to the flow in FIG. 23), a crimping and binding cancel operation is executed.

[0149] If the number of sheets accumulated in the pressure binding means 51 exceeds the maximum number of sheets that can be pressure bound, a cancellation process is performed without performing the pressure binding process by the pressure binding means 51. In this cancellation operation, when the maximum number of sheets that can be pressure bound is exceeded, the shifted sheet bundle, for which the bundle shift at the pressure binding position Ep has been completed, is discharged to the stack tray 49 without undergoing the binding process. After the shifted sheet bundle is discharged, the subsequent sheets that were to form this bundle are discharged after undergoing the shift operation described below.

[0150] When the maximum number of sheets that can be crimped increases, and the maximum number of sheets that can be crimped exceeds the maximum number of sheets that can be shifted in a bundle, the problem of multiple discharge positions to the stack tray 49 is addressed. In this embodiment, the maximum number of sheets that can be crimped is set to 10, but there may be cases where the number of sheets in a single bundle exceeds the upper limit of 10 sheets that can be crimped. For example, when the number of originals scanned by the scanner unit A2 exceeds 10, the number of sheets in a single bundle is unknown at the stage when scanning begins, and therefore the number of sheets in a single bundle may exceed the number that can be crimped.

[0151] When the number of sheets at the crimp binding position Ep after being shifted into a bundle is 10, which is the maximum number of sheets that can be crimped, and there are subsequent sheets in the same bundle, in this embodiment, a crimp binding cancel operation is performed in which the sheets at the crimp binding position Ep are discharged outside the machine without being crimped by the crimp binding means 51. This crimp binding cancel operation will be described in detail with reference to the flow in FIG.

[0152] First, when the count value of the number of sheets at the pressure binding position Ep is 10 and subsequent sheets of the same bundle are being transported from the image forming device A, the sheet being transported into the sheet processing device B (detection signal from the entrance sensor S1) triggers the pressure binding cancellation operation (Figure 13St46 and Figure 23St100).

[0153] In the press binding cancel operation, the sheet processing device B moves and pushes out the 10-sheet bundle at the press binding position Ep toward the first stack tray 49 using the sheet end regulating means 38 (push-out protrusion 38). Following this, the lift roller 41 is lowered to the press position, and the sheet bundle is nipped together with the driven roller 48 to transport the sheet bundle to the exit of the processing tray 37, and the bundle is discharged onto the stack tray 49 (St100). This operation is necessary because the structure of the press binding means 51 makes it difficult for the opening to accept subsequent sheets, making it difficult to accept subsequent sheets. At this time, the sheet bundle remains shifted to the press binding position Ep located at the rear of the device, and the discharge position on the first stack tray 49 is also shifted toward the rear of the device.

[0154] Since the subsequent sheets, from the 11th sheet onwards, are not subjected to pressure binding processing, there is no problem with the device if they are discharged to the first stack tray 49 in the same position (center position) as they were discharged from the sheet discharge port 35 onto the processing tray 37, but since the discharge position is different from that of the preceding sheet bundle that was originally supposed to form the same bundle, it is inconvenient and difficult for the user to remove them when stapling them after removal. Therefore, in this embodiment, the subsequent sheets are also shifted, and this operation will be described in detail below.

[0155] Although the subsequent eleventh and subsequent sheets are not subject to the pressure binding process, each time a sheet is discharged from the discharge rollers 36 (St101), the lifting rollers 41 and the paddle rotors 42 rotate to send the sheet to the sheet end regulating means 38 and stack it on the processing tray 37. In addition, in conjunction with this stacking process, the side edge aligning means 39 is moved from both sides in the sheet width direction to align the sheets to the center in the width direction of the processing tray 37. When the number of stacked sheets reaches the maximum number that can be shifted in a bundle or when there are no more subsequent sheets (St102), the sheets are shifted in a bundle to the pressure binding position Ep of the pressure binding means 51 (St103), and the sheet bundle in the pressure binding means 51 is moved and pushed up by the sheet end regulating means 38 (push-out protrusion 38) toward the exit side of the processing tray. Subsequently, the lift roller 41 is lowered to the pressure contact position, and the sheet bundle is nipped together with the driven roller 48 to transport the sheet bundle to the processing tray outlet side, and is discharged onto the stack tray 49 (St104).

[0156] This control repeats the process of stacking the sheets discharged from the image forming apparatus A onto the processing tray 37, shifting the bundle by the side edge alignment means 39, and discharging onto the stack tray 49 by the lift rollers 41 for all sheets of the same bundle (St105).

[0157] In the operation of shifting a stack of subsequent sheets to the pressure binding position Ep by the side edge alignment means 39, the number of sheets to be shifted in the stack may be any number of sheets as long as it is equal to or less than the maximum number for which the driving force of the side edge alignment means 39 is sufficient, or may be shifted one sheet at a time each time a subsequent sheet is discharged.

[0158] Furthermore, the number of sheets to be shifted in a bundle may be determined by using a weighted count value that takes into account the basis weight of the sheets to be shifted in a bundle, and the bundle may be shifted when the accumulated count value exceeds a predetermined value. This makes it possible to avoid poor movement due to insufficient driving force of the side edge aligning means 39 when shifting a bundle.

[0159] In the present invention, the above operation is performed to prevent sheets from being discharged to a different position on stack tray 49 when the number of sheets in the same bundle exceeds the maximum number that can be crimped and to prevent usability from being impaired, but on the other hand, there may also be cases where it is desired to quickly finish a job for which binding has been canceled (to prioritize productivity). For this reason, a selection means may be provided that allows the user to select whether to shift the sheets in the bundle to the crimp binding position Ep and discharge them even after the number of sheets in the same bundle exceeds the maximum number that can be crimped and bound, or to continue discharging them at the center until discharge is complete, and whether to shift the bundle to the crimp binding position Ep may be determined depending on the result of the selection means.

[0160] When the above-mentioned cancellation process is performed, the recognition means knows that the number of sheets in subsequent sheet bundles in the same job will already exceed the maximum number that can be crimped and bound, so the bundle number over flag is turned ON (the crimping and binding of subsequent bundles in the same job is also canceled), and it is desirable that after center alignment the bundles be discharged to stack tray 49 without shifting them.

[0161] The present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the scope of the present invention. All technical matters included in the technical ideas described in the claims are the subject of the present invention. The above-described embodiments are preferred examples, but a person skilled in the art can realize various alternatives, modifications, variations, or improvements from the contents disclosed in this specification, and these are included in the technical scope described in the appended claims. [Explanation of symbols]

[0162] A Image forming device B Sheet post-processing device B1 First processing section B2 Second processing section B3 Third Processing Section 26 Loading entrance 28 Sheet delivery route 30 Printout output path (third output path) 31 First switchback path (first paper output path) 32 Second switchback path (second paper output path) 35 Paper output slot 36 Paper ejection roller 37 Processing tray 38 Sheet edge control means 39 Side edge alignment means (side alignment member) 39F Front side alignment member 39R Rear side alignment member 41 Lifting roller (reversing conveying mechanism) 42 Paddle rotor (reversal transport mechanism) 46 Knurled belt (knurled rotor) 47 stapler unit (first binding means) 48 Driven roller 49 1st stack tray (1st storage section) 51 pressure binding means (second binding means) (second binding unit) 53 First running rail 54 Second running rail 56a First guide rod 56b Second guide rod 61 Second stack tray (second storage area) 71 Third stack tray (third storage area) 74 Differential means (transmission means) S1 Sheet Sensor 95 Control means (recognition means)

Claims

1. a conveying means for conveying the sheet in a predetermined conveying direction; a loading section for loading the sheet transported by the transport means; a sheet conveying unit provided downstream of the sheet placement unit in the conveying direction, the sheet conveying unit being stacked with the sheet conveyed from the sheet placement unit; a loading section, an alignment unit that is capable of aligning the sheet placed on the sheet placement unit in a sheet width direction perpendicular to the conveying direction, and of moving the aligned sheet in the sheet width direction to a shift position; a recognition unit for recognizing the size and number of sheets sent to the stacking unit; a control means for controlling the alignment means, the control means aligns the sheets by the aligning means every time a sheet is placed on the sheet placement section, and when the number of sheets reaches an upper limit number at which the aligning means can move the stack to the shift position based on the recognition result of the recognition means, causes the aligning means to move the stack to the shift position; A sheet processing apparatus characterized in that, after the stack moving operation is performed, the alignment means is controlled so that sheets that form the same stack as the sheet stack on which the stack moving operation has been performed and are sent to the stacking section are transported to the stacking section and then subjected to a one-sheet shift operation in which they are moved one sheet at a time to the shift position.

2. a conveying means for conveying the sheet in a predetermined conveying direction; a loading section for loading the sheet conveyed by the conveying means; an alignment unit that is capable of aligning the sheet placed on the sheet placement unit in a sheet width direction perpendicular to the conveying direction, and of moving the aligned sheet in the sheet width direction to a shift position; a recognition unit for recognizing the size and number of sheets sent to the stacking unit; a control means for controlling the alignment means, The control means controls the alignment means so that, when the recognition means recognizes that the sheets placed on the stacking section are small-size sheets whose length in the conveying direction is less than a predetermined length, the control means performs an alignment operation using the alignment means at the position where the sheets are placed until the number of sheets placed on the stacking section reaches a predetermined number, and then moves the sheets to the shift position; when the recognition means recognizes that the length of the sheets placed on the stacking section is large-size sheets whose length exceeds a predetermined length, the control means performs an alignment operation using the alignment means and then moves the sheets to the shift position when the number of sheets placed on the stacking section is less than the predetermined number and can be moved to the shift position by the alignment means, and controls the alignment means to perform a one-by-one shift operation in which the sheets transported to the stacking section by the transport means after the movement to the shift position reach the predetermined number.

3. a pressure binding unit that performs pressure binding processing on the sheets placed on the placement unit, The sheet binding processing device according to claim 1 or 2, wherein the sheets moved to the shift position by the aligning means are subjected to pressure binding processing.

4. the placement section includes a scraping means for scraping the sheets toward the placement section, The control means controls the pick-up means to have a standby position where the pick-up means is away from the sheet and a position where the pick-up means is moving to pick up the sheet. The alignment is performed while the material is being picked up at a pick-up position and a position between the standby position and the pick-up position. and a control means for controlling the raking means so that the raking means can move to a position where the raking means performs the one-sheet shift operation.

3. The sheet processing apparatus according to claim 1, wherein:

5. 5. The sheet processing apparatus according to claim 4, wherein the control means controls the pick-up means to pick up a sheet again after the one-sheet shift operation is completed, if the sheet that has been shifted by one sheet is the last sheet.

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