Post-processing device, and image forming system

Abstract

To eliminate trouble in removing a sheet bundle in which a binding process is not normally made, to be discriminated from a sheet bundle in which the binding process is normally made.SOLUTION: A post-processing device comprises: a saddle stitching processing part 81 (binding processing part) for giving binding processing to a sheet bundle PT including a plurality of sheets P; a staple detection sensor 77 (detection means) for detecting whether or not a binding process is normally made with respect to the sheet bundle PT scheduled to be given the binding processing at the saddle stitching processing part 81; a first saddle stitching discharge tray 73 (a first discharge part) to which the sheet bundle PT, detected to be normally given the binding processing by the staple detection sensor 77, is discharged; and a second saddle stitching discharge tray 74 (a second discharge part) to which the sheet bundle PT', detected to be not normally given the binding processing by the staple detection sensor 77, is discharged.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a post-processing device that performs a binding process on a sheet stack, and an image forming system that includes an image forming device such as a copying machine, a printer, a facsimile machine, or a combination machine or printing machine thereof. [Background technology]

[0002] Conventionally, in post-processing devices connected to image forming devices such as copiers and printers, when performing binding processes such as saddle stitching on a sheet stack, it is known to detect sheet stacks that have not been bound properly (see, for example, Patent Documents 1 and 2).

[0003] Meanwhile, Patent Document 1 discloses a technique for separating, by a sorting process, sheet bundles that have been bound properly and sheet bundles that have not been bound properly on one discharge tray. Furthermore, Patent Document 2 discloses a technique for notifying a user when a sheet bundle that has not been bound properly is detected. Summary of the Invention [Problem to be solved by the invention]

[0004] With conventional technology, it was necessary to distinguish and remove sheet bundles that were not properly bound and were discharged onto a single output tray, mixed in with sheet bundles that were properly bound, from the properly bound sheet bundles. This was time-consuming for the user, and if the machine had to be shut down to remove the sheet bundles, it also reduced the machine's productivity.

[0005] To provide a post-processing device and an image forming system that can solve the above-mentioned problems and eliminate the need to distinguish and remove sheet bundles that have not been bound properly from sheet bundles that have been bound properly. [Means for solving the problem]

[0006] The post-processing device of this invention includes a binding processing unit that binds a sheet bundle consisting of multiple sheets, a detection means that detects whether the sheet bundle that was scheduled to be bound by the binding processing unit has been bound normally, a first discharge unit that discharges the sheet bundle that has been detected by the detection means to have been bound normally, and a second discharge unit that discharges the sheet bundle that has been detected by the detection means to have not been bound normally. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a post-processing device and an image forming system that do not require the effort of distinguishing and removing sheet bundles that have not been bound properly from sheet bundles that have been bound properly. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is an overall configuration diagram showing an image forming system according to an embodiment of the present invention; [Figure 2] FIG. 2 is a diagram illustrating the configuration of a post-processing device. [Figure 3] FIG. 10 is a diagram showing an operation in a bookbinding processing mode. [Figure 4] FIG. 4 is a diagram illustrating the operation following FIG. 3. [Figure 5] (A) A diagram showing the operation of a sheet stack that has been properly saddle-stitched being discharged to the first discharge section, and (B) A diagram showing the operation of a sheet stack that has not been properly saddle-stitched being discharged to the second discharge section. [Figure 6] FIG. 2 is a block diagram showing a control system of the image forming system. [Figure 7] 10 is a flowchart illustrating an example of control during saddle stitching processing. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each drawing, the same or corresponding parts are designated by the same reference numerals, and redundant explanations will be appropriately simplified or omitted.

[0010] First, the overall configuration and operation of an image forming system 200 will be described with reference to FIG. In this embodiment, the image forming apparatus 1 is provided with a detachable post-processing device 50, and together with the post-processing device 50, constitutes one image forming system 200. In Figure 1, 1 indicates an image forming device that functions as a copier, 2 indicates an original reading unit that optically reads image information from an original D, and 3 indicates an exposure unit that irradiates exposure light L based on the image information read by the original reading unit 2 onto a photosensitive drum 5. Also, 4 indicates an image forming unit that forms a toner image (image) on the photosensitive drum 5, 7 indicates a transfer unit (image forming unit) that transfers the toner image formed on the photosensitive drum 5 to a sheet P, and 10 indicates a document transport unit that transports the set document D to the document reading unit 2. Further, 12 to 14 indicate a feeding section in which sheets P such as paper are stored, and 17 indicates a pair of registration rollers (a pair of timing rollers) that transport the sheets P toward the transfer section 7. Further, reference numeral 20 denotes a fixing device that fixes an unfixed image on the sheet P, 21 denotes a fixing roller installed in the fixing device 20, and 22 denotes a pressure roller installed in the fixing device 20. Also, 30 indicates a double-sided conveying section that inverts the sheet P after an image has been formed on its front side and conveys it toward the image forming section, and 49 indicates an operation display panel for displaying information related to the printing operation (image forming operation) and post-processing operation and for performing operations. Further, 50 indicates a post-processing device that performs post-processing on sheets P discharged from the image forming device 1 and transported in, 71 to 74 indicate discharge trays on which sheets P (or sheet stacks) after post-processing are stacked, 80 indicates a bookbinding processing device installed in the post-processing device 50, and 90 indicates an end-stitching device installed in the post-processing device 50.

[0011] With reference to FIG. 1, the operation of image forming apparatus 1 (image forming system 200) during normal image formation (printing) will be described. First, the document D is transported from the document table in the direction of the arrow in the figure by the transport rollers of the document transport unit 10, and passes over the document reading unit 2. At this time, the document reading unit 2 optically reads the image information of the document D passing above it. The optical image information read by the document reading unit 2 is converted into an electrical signal and then transmitted to the exposure unit 3 (writing unit). The exposure unit 3 then emits exposure light L, such as a laser beam, based on the image information in the electrical signal onto the photosensitive drum 5 of the imaging unit 4.

[0012] Meanwhile, in the image creating unit 4, the photosensitive drum 5 rotates clockwise in the figure, and after going through a predetermined image creating process (charging process, exposure process, and development process), an image (toner image) corresponding to the image information is formed on the photosensitive drum 5. Thereafter, the image formed on the photosensitive drum 5 is transferred onto a sheet P conveyed by a pair of registration rollers 17 in a transfer unit 7 serving as an image forming unit.

[0013] On the other hand, the sheet P conveyed to the transfer unit 7 (image forming unit) operates as follows. First, one of the plurality of feeding units 12 to 14 of the image forming apparatus 1 is automatically or manually selected (for example, it is assumed that the uppermost feeding unit 12 is selected). Then, the uppermost sheet of the sheets P stored in the feeding section 12 is conveyed toward the position of the conveying path K1.

[0014] Thereafter, the sheet P passes through a conveying path K1 on which a plurality of conveying rollers are arranged, and reaches the position of a pair of registration rollers 17. Then, the sheet P that has reached the position of the pair of registration rollers 17 is conveyed toward a transfer unit 7 (image forming unit) in time for alignment with the image formed on the photosensitive drum 5.

[0015] After the transfer process, the sheet P passes through the position of the transfer unit 7, and then travels through a conveying path to reach the fixing device 20. The sheet P that has reached the fixing device 20 is fed between the fixing roller 21 and the pressure roller 22, where the image is fixed by the heat received from the fixing roller 21 and the pressure received from both members 21 and 22. The sheet P with the fixed image is sent out from between the fixing roller 21 and the pressure roller 22 (the nip portion), and then discharged from the image forming apparatus 1.

[0016] When a "double-sided print mode" is selected in which printing is performed on both sides (front and back sides) of the sheet P, the sheet P after the fixing process on the front side is not discharged as is as when the above-mentioned "single-sided print mode" is selected, but is guided to the double-sided conveying path K2, where the conveying direction is reversed by the double-sided conveying section 30 and then conveyed again toward the position of the transfer section 7 (image forming section). Then, at the position of the transfer section 7, an image is formed on the back side of the sheet P by the same image forming process as described above, and then the sheet P undergoes the fixing process in the fixing device 20, passes through the conveying path, and is discharged from the image forming apparatus 1.

[0017] Here, in this embodiment, a post-processing device 50 is connected to the image forming device 1, and the sheet P discharged from the image forming device 1 is transported to the post-processing device 50, where post-processing is performed on the transported sheet P. 1, post-processing device 50 in this embodiment is configured to convey sheets P conveyed from image forming device 1 to one of three conveying paths K3 to K5 and perform different post-processing. First conveying path K3 is a conveying path for discharging sheets P conveyed from image forming device 1 directly onto first discharge tray 71 without performing post-processing. Second conveying path K4 is a conveying path for stacking sheets P conveyed from image forming device 1 onto internal tray 61, performing binding processing (end binding processing) on ​​the trailing ends of the sheets by end stitching processing section 91 of end stitching device 90, and discharging processed sheets P (sheet stack PT) from discharge opening 50b to second discharge tray 72 by discharge rollers 54. The third conveying path K5 is used to convey the sheet P conveyed from the image forming device 1 to the second conveying path K4, switch back, and then perform saddle stitching processing at the center of the sheet by the saddle stitching processing unit 81 of the binding processing device 80, or center folding processing by the center folding processing unit 87, and then discharge the sheet to the first saddle stitching discharge tray 73 (first discharge unit) via the horizontal conveying path K6. The above-mentioned three transport paths K3 to K5 are switched by the switching operation (rotation) of a branching claw 75 (see FIG. 2). In addition, the bookbinding processing device 80 of the post-processing device 50 in this embodiment is provided with a second saddle stitching discharge tray 74 (second discharge section) for discharging sheet bundles PT for which the saddle stitching process has not been performed normally, which will be described in detail later using Figure 5 etc.

[0018] 2, a first conveying roller 51 and a sheet detection sensor (not shown) are installed near the entrance 50a of the post-processing device 50, and the sheet P detected by the sheet detection sensor is conveyed into the device 50 by the conveying roller 51. Then, based on the post-processing mode selected in advance by the user, a branching claw 75 rotates so that the sheet P is guided to a desired conveying path K3 to K5. When a mode in which post-processing is not performed is selected, the sheet P conveyed to the first conveying path K3 is discharged by the pair of discharge rollers 53 and placed on the first discharge tray 71. On the other hand, if the user selects "perforation processing (punch processing)" on the operation display panel 49, the perforation processing unit 60 performs perforation processing on the sheet P as the sheet P passes through the perforation processing unit 60.

[0019] Furthermore, when the "sorting mode (sorting processing mode)" is selected, the sheets P transported to the second transport path K4 are transported while being shifted in the width direction by a predetermined amount for each sheet P by a pair of shift rollers 55 configured to be movable in the width direction (the direction perpendicular to the paper surface in Figure 2), and are further transported to the discharge rollers 54 and stacked sequentially on the second discharge tray 72.

[0020] 2, a filler 82 is provided above the second discharge tray 72 so as to be rotatable about a support shaft at the upper end, and the second discharge tray 72 is configured to be movable up and down by a lifting mechanism (not shown). A sensor installed near the support shaft of the filler 82 detects a state in which the center portion in the transport direction of the sheets P sequentially stacked on the second discharge tray 72 contacts the filler 82, thereby recognizing the height of the sheets P stacked on the second discharge tray 72. The vertical position of the second discharge tray 72 is adjusted in accordance with an increase or decrease in the number of sheets P stacked on the second discharge tray 72. Furthermore, when the vertical position of the second discharge tray 72 reaches its lower limit, it is determined that the number of sheets P stacked on the second discharge tray 72 has reached the upper limit (full), and a stop signal is transmitted from the post-processing device 50 to the image forming apparatus 1 to stop the image forming operation.

[0021] Furthermore, when the "edge binding processing mode (edge ​​staple mode)" is selected, the sheets P transported to the second transport path K4 are sequentially stacked on the internal tray 61 without being shifted by the shift roller pair 55. Then, each time a sheet P (sheet stack PT) is placed on the internal tray 61, the sheet P is transported toward the end fence 66 by the transport rollers. As a result, the rear ends (rear ends in the transport direction) of the multiple sheets P (sheet stack PT) hit the end fence 66, and the positions of the multiple sheets P in the transport direction are aligned.

[0022] At this time, the jogger fences 68 (side fences) installed at both widthwise ends of the internal tray 61 move in the widthwise direction to sandwich the sheets P (sheet stack PT) every time a sheet P is placed on the internal tray 61 (or after a desired number of sheets P are stacked), thereby aligning the widthwise position of the sheets P (sheet stack PT). Then, the end binding processing unit 91 performs binding processing on the rear end of the sheets P (sheet stack PT) that has been aligned in both the conveying direction and the widthwise direction. Thereafter, the bound sheets P (sheet stack PT) are transported obliquely upward along the inclined surface of the internal tray 61, and are discharged to the outside by the transport by the discharge rollers 54, and are placed on the second discharge tray section 72.

[0023] Furthermore, when the "bookbinding mode (saddle stitching & center folding mode)" is selected, referring to FIG. 2, the sheet P is first conveyed to the second conveying path K4, and with its rear end sandwiched between the shift roller pair 55, the shift roller pair 55 is rotated in the reverse direction to switch back, and the sheet P is conveyed to the third conveying path K5. The sheet P conveyed to the third conveying path K5 is then conveyed to the position of the bookbinding processing device 80 by a plurality of conveying roller pairs. Specifically, the sheet P is conveyed to a position where the center of the sheet P faces the saddle stitching processing unit 81 (a position where a conveying guide plate, not shown, functions as an internal tray). Then, after a desired number of sheets P (sheet bundle PT) are stacked at that position, the saddle stitching processing unit 81 performs a binding process (saddle stitching process) on the center of the sheet bundle PT. Thereafter, the saddle-stitched sheets P (sheet stack PT) are conveyed to a position where the center of the sheet stack PT faces the folding blade 88 by the movement of the aligning devices 84 and 85 by a moving mechanism (not shown). At this time, the leading edge of the sheet stack PT abuts against the end fence 84, and the position in the conveying direction is aligned. In addition, each time a sheet P is placed on the internal tray (or after a desired number of sheets P have been stacked), side fences 86 installed at both ends of the internal tray in the width direction move in the width direction to sandwich the sheet P (sheet stack PT), and the position in the width direction of the sheet P (sheet stack PT) is aligned. Then, with the central portion Pm (see FIGS. 3 and 4) of the sheet stack PT folded by the folding blade 88 moving leftward in FIG. 2, the sheet stack PT is nipped and conveyed by the pair of folding rollers 89 along the horizontal conveyance path K6 with the folded portion (central portion Pm) at the leading edge, while being pressed against each other, and is subjected to a folding process (center folding process). The sheet stack PT after the center folding process is then conveyed by the pair of discharge rollers 59 and placed on the first saddle stitching discharge tray 73 as the first discharge section. Note that, like the second discharge tray 72, the first saddle stitching discharge tray 73 may also be configured to be movable up and down by a lifting mechanism (not shown), and may be lowered depending on the number of sheets of the sheet stack PT stacked on the tray. In this way, a series of bookbinding processing modes (saddle stitching and center folding processing modes) is completed. The configuration and operation of the bookbinding processing device 80 will be explained in more detail later with reference to FIGS.

[0024] The above-mentioned modes relating to the various post-processing processes are selected by the user operating the operation display panel 49 of the image forming apparatus 1. Furthermore, the post-processing device 50 executes the various modes described above by the control unit 100 installed within the device (or within the image forming device 1).

[0025] The configuration and operation of the bookbinding processing device 80 installed in the post-processing device 50 in this embodiment will be described in detail below. As previously explained using Figure 2 etc., the post-processing device 50 in this embodiment is provided with a binding processing device 80 for performing binding processing (saddle stitching processing & center folding processing) on ​​sheets P (multiple sheets P) printed by the image forming device 1. This bookbinding processing device 80 is provided with a saddle stitching processing section 81 as a binding processing section, a center folding processing section 87, an alignment device consisting of an end fence 84 and a claw member 85, a first saddle stitching discharge tray 73 as a first discharge section, and a second saddle stitching discharge tray 74 as a second discharge section.

[0026] 2, 3(A) to 3(C), etc., a saddle stitching processing section 81 serving as a binding processing section is provided with a driver 81a and a clincher 81b on either side of a conveyance path. The driver 81a is a part that holds staples to be driven into a sheet stack PT consisting of multiple sheets P. Although not shown in the figure, the staples held by the driver 81a are sequentially fed from a refill (staple cartridge) by a push-out tooth that moves when driven by a drive motor. The clincher 81b faces the driver 81a through the sheet stack PT and deforms the staples that have been driven into the sheet stack PT. Although not shown, the clincher 81b is driven by a drive motor to move in a direction toward and away from the driver 81a. As the drive motor is driven, the clincher 81b moves toward the driver 81a via the sheet stack PT and presses against the staple (which has penetrated the sheet stack PT) held by the driver 81a, crushing the tip of the roughly U-shaped staple toward the center around the bent portion. As a result, the center portion Pm of the sheet stack PT is stapled by the staple X, as shown in FIG. 3(a). The needle X in this embodiment is made of a metal material.

[0027] 2, 4, etc., the center-folding processing section 87 is disposed upstream in the conveying direction (upper in FIG. 3) of the saddle-stitching processing section 81. The center-folding processing section 87 is mainly composed of a folding blade 88 and a pair of folding rollers 89. 4A, the folding blade 88 is a blade-shaped member that pushes the center Pm of the sheet P (including the sheet stack PT) when performing the center folding process. The folding blade 88 is configured to be movable in the left-right direction in FIG. 4 by a moving means (for example, a rack and pinion mechanism) (not shown) controlled by the control unit 100. 4A and 4B, the pair of folding rollers 89 is a pair of rollers that sandwich and transport the sheet P (including the sheet stack PT) pushed by the folding blade 88, with the center portion Pm of the sheet P being the leading edge. The pair of folding rollers 89 is configured to be rotatable in the direction of the arrow in FIG. 4 by a motor (not shown) controlled by the control unit 100. As shown in Figures 4(A) and (B), the sheet stack PT is pushed into the nip of the pair of folding rollers 89 by the folding blade 88, and a crease is formed in the center Pm of the sheet stack PT by the pair of folding rollers 89 clamping and transporting it, thereby performing a center folding process.

[0028] Referring to Figures 2 to 4, etc., the alignment devices 84, 85 (alignment devices) are mechanisms for receiving sheets P transported in a predetermined transport direction (the direction of the arrow in Figure 3(A)) in a stackable manner and aligning the position (posture) of the sheets P (including the sheet stack PT) in the transport direction. The aligning device mainly includes an end fence 84 and a claw member 85. The aligning devices 84 and 85 are held by the device housing so as to be movable in the conveying direction (the up and down direction in FIGS. 2 and 3). As shown in FIG. 3A, the end fence 84 is a fence-like member against which the leading edge of the sheet P in the conveying direction abuts. The claw member 85 is a member that pushes (hits) the trailing end of the sheet P in the conveying direction when it abuts against the end fence 84 toward the end fence 84. The claw member 85 is configured to be rotatable about a support shaft. When the sheet P passes through this position, the claw member 85 rotates to a retracted position where it does not interfere with the sheet P, and when the sheets P are aligned (during alignment processing), the claw member 85 rotates to a pushing position where it pushes the trailing end of the sheet P. Furthermore, during alignment processing, the claw member 85 repeatedly rotates in forward and reverse directions at a small angle about the support shaft so as to repeatedly hit the trailing end of the sheet P downward.

[0029] Also, referring to Figure 2, the alignment device in this embodiment is provided with a side fence 86 that moves in a width direction (perpendicular to the paper surface of Figure 2) perpendicular to the conveying direction to align the widthwise position (posture) of the sheet P. The side fences 86 are installed at both ends in the width direction. Each time a sheet P is placed on the aligning device (or after a desired number of sheets P have been stacked), the pair of side fences 86 moves in the width direction to sandwich the sheet P (sheet stack PT), thereby aligning the position of the sheet P (sheet stack PT) in the width direction. In this embodiment, a pair of conveying rollers 83 is provided near the claw member 85.

[0030] Below, using Figures 3(A) to (C) and Figures 4(A) and (B), we will explain the operation of performing a center-stitching process (a process of binding the center portions Pm of the multiple sheets P) on a sheet bundle PT consisting of multiple sheets P, and then performing a center-folding process (a process of folding the center portion Pm of the sheet bundle PT). 3A, a movement mechanism (not shown) is used to move the end fence 84 and the claw members 85 in the vertical direction to optimal positions (positions where the center Pm of the sheet P faces the binding position of the saddle stitching processing unit 81), and after that position is determined and fixed (movement is stopped), the alignment devices 84, 85 (saddle stitching processing unit 81) are controlled to receive the sheet P. Then, the alignment devices 84, 85 (including side fences 86) align the sheet stack PT in the conveyance direction and width direction, and then the saddle stitching processing unit 81 performs saddle stitching. 3(B) and 3(C), the saddle stitching processing unit 81 performs saddle stitching on the sheet bundle PT aligned by the end fence 84, the claw members 85, and the side fences 86, and then the movement mechanism (not shown) moves the end fence 84, the claw members 85, and the side fences 86 upward together with the sheet bundle PT so that the center Pm of the sheet bundle PT faces the tip of the folding blade 88. At this time, since the sheet bundle PT has been saddle stitched, the alignment is hardly disturbed even if it moves upward as if pushed by the end fence 84. As shown in Figures 4(A) and (B), the central portion Pm of the sheet stack PT is folded by the folding blade 88 moving to the left in Figure 4, and the sheet stack PT is then subjected to a center folding process by being clamped, conveyed, and pressed by a pair of folding rollers 89 with the folded portion (central portion Pm) at the front.

[0031] The characteristic configuration and operation of post-processing device 50 in this embodiment will be described in detail below. As previously explained using Figures 2 to 4, the post-processing device 50 (bookbinding processing device 80) in this embodiment is provided with a saddle stitching processing device 81 as a binding processing device that performs binding processing on a sheet bundle PT consisting of multiple sheets P. The saddle stitching processing unit 81 as a binding processing unit is configured to perform a saddle stitching process that binds the center Pm of the sheet bundle PT as a binding process. This saddle stitching processing unit 81 (binding processing unit) performs the saddle stitching process (binding process) using a metal staple X (see FIG. 3(a)). The post-processing device 50 (bookbinding device 80) is also provided with a center-folding processing unit 87 that folds the center portion Pm of the sheet bundle PT that has been subjected to the saddle-stitching processing.

[0032] Now, referring to Figures 2, 5, etc., the post-processing device 50 (bookbinding processing device 80) in this embodiment is provided with a needle detection sensor 77 as a detection means for detecting whether or not the binding process has been performed normally on the sheet bundle PT that was scheduled to be subjected to saddle stitching processing (binding process) in the saddle stitching processing unit 81 (binding processing unit). In detail, the needle detection sensor 77 (detection means) detects whether the binding process has been performed correctly on the sheet stack PT after the center folding process has been performed by the center folding processing unit 87, and detects the presence or absence of a needle X made of metal material. The needle detection sensor 77 magnetically detects, without contact, whether or not needle X is present in the leading folded portion (center portion Pm) of the sheet bundle PT after it has passed through the nip of the discharge roller pair 59 on the horizontal conveyance path K6, which is a conveyance path on which the folding roller pair 89 and the discharge roller pair 59 are installed. Such a needle detection sensor 77 detects the presence or absence of needle X by the difference in magnetic permeability, and a known needle detection sensor can be used. The needle detection sensor 77 can detect a state in which needle X is not properly inserted, because the magnetic permeability changes not only when no needle X is inserted in the sheet bundle PT at all, but also when needle X is inserted at an angle relative to the sheet bundle PT in the conveyance direction, width direction, or piercing direction, but also when needle X is inserted normally without being tilted relative to the sheet bundle PT in the conveyance direction, width direction, or piercing direction. In this embodiment, a needle detection sensor 77 is used that magnetically detects the presence or absence of needles X in the sheet stack PT without contact, but a contact sensor or a non-contact sensor that can detect needles X in the sheet stack PT can also be used as the needle detection sensor.

[0033] Now, referring to Figures 2, 5, etc., the post-processing device 50 (bookbinding processing device 80) in this embodiment is provided with two discharge trays (a first saddle-stitch discharge tray 73 as the first discharge section and a second saddle-stitch discharge tray 74 as the second discharge section) and a branch claw 75 as a switching means.

[0034] The first saddle stitching discharge tray 73 functions as a first discharge portion onto which the sheet bundle PT is discharged after it has been detected by the staple detection sensor 77 (detection means) that it has been normally saddle stitched (stitched). In contrast, the second saddle stitching discharge tray 74 functions as a second discharge section to which the sheet bundle PT' is discharged when the staple detection sensor 77 (detection means) detects that the saddle stitching process (binding process) has not been performed properly. The branch claw 75 is provided on the horizontal conveyance path K6, which is a conveyance path along which the sheet bundle PT is conveyed after the staple detection sensor 77 (detection means) detects whether the sheet bundle PT has been properly bound. The branch claw 75 functions as a switching means for switching whether the sheet bundle PT is to be discharged to the first saddle stitching discharge tray 73 (first discharge section) or the second saddle stitching discharge tray 74 (second discharge section) depending on the result of the staple detection sensor 77.

[0035] In detail, the first saddle stitching discharge tray 73 as the first discharge section is arranged to extend approximately horizontally (including in a direction inclined to a certain extent from the horizontal direction) on the extension of the horizontal conveying path K6, and is a tray with an open top. In contrast, the second saddle stitching discharge tray 74 as the second discharge section is arranged to extend approximately vertically below the horizontal conveying path K6 and the first saddle stitching discharge tray 73 (first discharge section), and is a tray that is closed in an approximately box-like shape. By configuring and arranging the first and second saddle stitching discharge trays 73, 74 in this way, it becomes easier for the user to remove a normally processed sheet bundle PT from the first saddle stitching discharge tray 73. Furthermore, it is possible to reduce the problem of mistaking an abnormally processed sheet bundle PT' stacked on the second saddle stitching discharge tray 74, which is configured to make it difficult to remove both visually and functionally, for a normally processed sheet bundle.

[0036] The branch claw 75 as a switching means is formed to be rotatable about a rotation shaft 75a under the control of a motor 110 by the control unit 100. The branch claw 75 is installed at a portion where a conveying path from the discharge roller pair 59 to the first saddle stitching discharge tray 73 and a conveying path from the discharge roller pair 59 to the second saddle stitching discharge tray 74 branch off.

[0037] 5(A), when the staple detection sensor 77 detects the sheet stack PT in a state where the saddle stitching process has been properly performed (a state where the staple X is inserted properly), the control unit 100 controls the motor 110 so that the branch claw 75 remains in the reference position (the position in FIG. 5(A)), and the sheet stack PT conveyed by the discharge roller pair 59 is sequentially stacked on the first saddle stitching discharge tray 73. Then, the user takes out the normal sheet stack PT stacked on the first saddle stitching discharge tray 73. In contrast, as shown in FIG. 5B, when the staple detection sensor 77 detects a sheet bundle PT' in a state where the saddle stitching process has not been performed properly (a state where the staple X has not been inserted properly), the control unit 100 controls the motor 110 to rotate the branch claw 75 from the reference position to the change position (the position in FIG. 5B). Then, the sheet bundle PT' conveyed by the discharge roller pair 59 is conveyed downward along the shape of the branch claw 75 and is stacked sequentially on the second saddle stitching discharge tray 74. The user then removes and disposes of the sheet bundle PT' that has not been properly saddle stitched and is stacked on the second saddle stitching discharge tray 74 at an appropriate time.

[0038] In this way, the post-processing device 50 (bookbinding device 80) in this embodiment detects whether the saddle stitching process has been performed normally on the sheet bundle PT using the staple detection sensor 77, and based on the detection result, determines whether to discharge the sheet bundle PT to the first saddle stitching discharge tray 73 or the second saddle stitching discharge tray 74. This eliminates the need to distinguish and remove the sheet bundle PT' that has not been saddle stitched normally from the sheet bundle PT that has been bound normally.

[0039] In this embodiment, when the saddle stitching processing unit 81 (stapling processing unit) binds the sheet bundle PT at multiple locations using staples X (two locations in the example of Figure 3(a)), if the staple detection sensor 77 (detection means) detects that the sheet bundle PT has not been properly bound by even one of the multiple staples X, the sheet bundle PT is controlled to be discharged to the second saddle stitching discharge tray 74 (second discharge unit).

[0040] Here, referring to Figure 5 etc., in this embodiment, at least one of the first saddle stitching discharge tray 73 (first discharge section) and the second saddle stitching discharge tray 74 (second discharge section) is provided with fullness detection sensors 78, 79 that detect when the sheet stack PT is full. When the full state of the sheet stack PT is detected by the full state detection sensors 78 and 79, the fact is controlled to be notified. More specifically, in this embodiment, a first fullness detection sensor 78 is provided that can detect a state in which the first saddle stitching discharge tray 73 is full of sheet bundles PT (which have been processed normally). As this first fullness detection sensor 78, for example, a distance measurement sensor that can detect the stacking height of multiple sheet bundles PT stacked on the first saddle stitching discharge tray 73 can be used. Then, when the first fullness detection sensor 78 detects a fullness state, the control unit 100, based on the detection result, suspends the bookbinding process mode and displays on the operation display panel 49 that the first saddle stitching discharge tray 73 is full, prompting the user to remove the sheet bundle PT from the first saddle stitching discharge tray 73. Also provided is a second fullness detection sensor 79 (for example, a distance measurement sensor) that can detect a state in which the second saddle stitching discharge tray 74 is full of sheet bundle PT' (which has not been processed normally). When the second fullness detection sensor 79 detects a fullness state, the control unit 100, based on the detection result, suspends the bookbinding processing mode and displays on the operation display panel 49 that the second saddle stitching discharge tray 74 is full, prompting the user to remove the sheet bundle PT' on the second saddle stitching discharge tray 74. This configuration improves ease of use for the user in the bookbinding mode.

[0041] In this embodiment, it is also possible to select a "limitless discharge mode" in which, after the first full detection sensor 78 (full detection sensor) detects that the first saddle stitching discharge tray 73 (first discharge section) is full of sheet bundles PT, the staple detection sensor 77 (detection means) detects that the sheet bundles PT have been successfully bound, and discharges the sheet bundles PT to the second saddle stitching discharge tray 74 (second discharge section). Specifically, the post-processing device 50 (bookbinding device 80) in this embodiment is basically a limit discharge type. That is, when either the first fullness detection sensor 78 or the second fullness detection sensor 79 detects a full state of the sheet bundle PT, the device controls the device to suspend discharge to both saddle stitching discharge trays 73 and 74 (suspend the bookbinding process itself). However, if the user operates the operation display panel 49 as needed to select the "limitless discharge mode," even if the first saddle stitching discharge tray 73 becomes full, the sheet bundles PT that are subsequently successfully saddle stitched are discharged to the second saddle stitching discharge tray 74 until the second saddle stitching discharge tray 74 becomes full. When the "limitless discharge mode" is selected in this way, abnormal sheet bundles PT' and normal sheet bundles PT are mixed in the second saddle stitching discharge tray 74, but this has the advantage of not interrupting the operation of the device (bookbinding process mode).

[0042] The control system of the image forming system 200 will be briefly described below with reference to FIG. The post-processing device 50 is provided with a control circuit equipped with a microcomputer having a CPU 100 (controller) and an I / O interface 102. Signals from the CPU of the image forming device 1, the switches and sensors (not shown) of the operation display panel 49, etc. are input to the CPU 100 via a communication interface 103, and the CPU 100 executes predetermined control based on the input signals. Furthermore, the CPU 100 controls the driving of solenoids and motors via drivers and motor drivers, and acquires sensor information within the device from the interface. Also, depending on the control target and sensor, the CPU 100 controls the driving of motors using motor drivers via the I / O interface 102, and acquires sensor information from the sensors. Such control is executed based on the program defined by the above-mentioned program code, with CPU 100 reading the program code stored in ROM (not shown) and expanding it into RAM (not shown), and using the RAM as a work area and data buffer.

[0043] An example of control when saddle stitching is performed by the post-processing device 50 will be described below with reference to FIG. As shown in FIG. 7, when the saddle stitching process (assumed to be a saddle stitching process in which two staples X are inserted) is executed, first, at the position where the sheet stack PT has passed the pair of discharge rollers 59, the staple detection sensor 77 detects whether both staples X have been inserted correctly at the desired positions in the sheet stack PT (step S1). As a result, if both staples X are properly inserted into the desired positions of the sheet bundle PT, the branch claw 75 remains in the reference position (the position in FIG. 5(A)), and the sheet bundle PT is discharged to the first saddle stitching discharge tray 73 (first discharge section) (step S2).Then, the flow from step S1 onwards is repeated until the first fullness detection sensor 78 detects that the first saddle stitching discharge tray 73 (first discharge section) is full, or until the series of jobs (saddle stitching processing) is completed (step S3). On the other hand, if at least one staple X is not properly inserted into the desired position of the sheet bundle PT in step S1, the branch claw 75 is rotated from the reference position to the changed position (the position in FIG. 5(B)) (step S4), and the sheet bundle PT is discharged to the second saddle stitching discharge tray 74 (second discharge section) (step S5). Then, when the second fullness detection sensor 79 detects that the second saddle stitching discharge tray 74 (second discharge section) is full or when the series of jobs (saddle stitching processing) has ended, this flow ends (step S6); otherwise, the branch claw 75 is returned from the changed position to the reference position (steps S6, S7), and the flow from step S1 onwards is repeated.

[0044] As described above, the post-processing device 50 in this embodiment is provided with the saddle stitching processing unit 81 (binding processing unit) that binds a sheet bundle PT consisting of a plurality of sheets P, and the staple detection sensor 77 (detection means) that detects whether the sheet bundle PT that was scheduled to be bound by the saddle stitching processing unit 81 has been properly bound. Furthermore, the post-processing device 50 is provided with a first saddle stitching discharge tray 73 (first discharge unit) to which the sheet bundle PT that has been detected by the staple detection sensor 77 as having been properly bound is discharged, and a second saddle stitching discharge tray 74 (second discharge unit) to which the sheet bundle PT' that has been detected by the staple detection sensor 77 as having not been properly bound is discharged. This eliminates the need to distinguish and remove the sheet bundle PT' that has not been bound properly from the sheet bundle PT that has been bound properly.

[0045] In this embodiment, the present invention is applied to a post-processing device 50 connected to a monochrome image forming device 1, but the present invention can naturally also be applied to a post-processing device connected to a color image forming device. Furthermore, in this embodiment, the present invention is applied to a post-processing device 50 connected to an electrophotographic image forming apparatus 1, but the application of the present invention is not limited to this, and the present invention can naturally also be applied to post-processing devices connected to other types of image forming apparatuses (for example, inkjet image forming apparatuses, stencil printing machines, etc.). In addition, the present invention can also be applied to a post-processing device that is a standalone device (for example, a device in which a paper feed cassette is set in the entrance 50a and an operation display panel for inputting processing modes, etc. is installed on the post-processing device itself) rather than a post-processing device 50 connected to the image forming device 1. Furthermore, in this embodiment, the present invention is applied to a bookbinding processing device 80 in which a saddle stitching processing unit 81 is provided as a binding processing unit in the post-processing device 50, but the present invention can also be applied to a device in which a binding processing unit other than a saddle stitching processing unit is provided (for example, a binding device 90 in which an end stitching processing unit 91 is provided). Furthermore, in this embodiment, the present invention is applied to post-processing device 50 that can perform edge binding, sorting, saddle stitching, center folding, and punching, but the application of the present invention is not limited to this, and, for example, the present invention can naturally be applied to post-processing devices that exclusively perform the two post-processing steps of saddle stitching and center folding. In this embodiment, the present invention is applied to a post-processing device 50 in which the bookbinding device 80 is configured so that the sheet P carried in from the carry-in entrance 50a is not transported to the position of the internal tray 61, but is branched off and transported to the third transport path K5 for bookbinding. However, the configuration of the bookbinding device 80 is not limited to this, and the present invention can also be applied to, for example, a post-processing device in which a bookbinding device is installed in which the sheet P carried in from the carry-in entrance 50a is branched off and transported from the transport path leading from the internal tray 61 to the discharge rollers 54 for bookbinding. Even in such cases, the same effects as those of this embodiment can be obtained.

[0046] It is clear that the present invention is not limited to the present embodiment, and that within the scope of the technical concept of the present invention, the present embodiment may be modified as appropriate in addition to the modifications suggested in the present embodiment. Furthermore, the number, position, shape, etc. of the components are not limited to the present embodiment, and the number, position, shape, etc. of the components may be any number, position, shape, etc. that is suitable for implementing the present invention.

[0047] In this specification, the term "sheet" is defined to include not only paper but also all sheet-like materials that are the subject of post-processing. [Explanation of symbols]

[0048] 1 Image forming apparatus (image forming apparatus main body), 50 aftertreatment device, 59 discharge roller pair, 73 First saddle stitching output tray (first output section), 74 Second saddle stitching output tray (second output section), 75 Branch claw (switching means), 77 Needle detection sensor (detection means), 78 First full detection sensor (full detection sensor), 79 Second full detection sensor (full detection sensor), 80 Bookbinding processing equipment, 81 saddle stitching processing section (stitching processing section), 81a driver, 81b clincher, 83 conveying roller pair, 84 End fence, 85 Claw member, 86 side fence, 87 Center-fold processing unit, 88 folding blade, 89 folding roller pair, 200 Image forming system, K6 horizontal transport path (transport path), P sheets, PT, PT´ sheets bundles.

[0049] The present invention can also be embodied in a combination of Supplementary Notes 1 to 9, as follows. (Appendix 1) a binding processing unit that binds a sheet bundle made up of a plurality of sheets; a detection means for detecting whether the sheet bundle scheduled to be bound by the binding processing unit has been normally bound; a first discharge section to which a sheet bundle detected by the detection means as having been normally bound is discharged; a second discharge section to which a sheet bundle detected by the detection means as not having been bound normally is discharged; A post-processing device comprising: (Appendix 2) The post-processing device described in Appendix 1 is characterized in that a switching means is provided in a transport path along which a sheet bundle that has been detected by the detection means as having been properly bound is transported, and which switches whether the sheet bundle is discharged to the first discharge section or the second discharge section depending on the result of the detection means. (Appendix 3) the first discharge section is a tray that is disposed so as to extend substantially horizontally on an extension of the conveyance path and has an open top, The post-processing device described in Appendix 2, characterized in that the second discharge section is a tray that is arranged to extend approximately vertically below the conveying path and the first discharge section and is closed in an approximately box-like shape. (Appendix 4) The binding processing unit performs binding processing using staples, 4. The post-processing device according to any one of claims 1 to 3, wherein the detection means detects the presence or absence of the needle. (Appendix 5) The post-processing device described in Appendix 4 is characterized in that when the binding processing unit binds a sheet stack using staples at multiple locations, if the detection means detects that the sheet stack has not been bound properly with any one of the multiple staples, the sheet stack is discharged to the second discharge unit. (Appendix 6) At least one of the first discharge section and the second discharge section includes a full-sheet detection sensor that detects a state in which the sheet stack is full, 6. The post-processing device according to any one of claims 1 to 5, wherein when the full state of the sheet stack is detected by the full state detection sensor, a notification to that effect is given. (Appendix 7) The post-processing device described in Appendix 6 is configured to be able to select a limitless discharge mode in which, after the fullness detection sensor detects that the first discharge section is full of sheet bundles, the detection means detects that the sheet bundles have been successfully bound, and the post-processing device is configured to be able to select a limitless discharge mode in which the post-processing device discharges the sheet bundles to the second discharge section. (Appendix 8) The binding processing unit is configured to perform a saddle stitching process for binding a central portion of a sheet bundle as a binding process, a center-folding processing section that folds the center of the sheet bundle that has been subjected to the saddle-stitching processing, The post-processing device according to any one of appendices 1 to 7, wherein the detection means detects whether or not the sheet stack has been properly bound after being center-folded by the center-folding processing unit. (Appendix 9) An image forming system comprising: an image forming apparatus that forms an image on a sheet; and a post-processing apparatus according to any one of appendices 1 to 8 that performs post-processing on the sheet on which the image has been formed by the image forming apparatus. [Prior art documents] [Patent documents]

[0050] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-142029 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-56758

Claims

1. a binding processing unit that binds a sheet bundle made up of a plurality of sheets; a detection means for detecting whether the sheet bundle scheduled to be bound by the binding processing unit has been normally bound; a first discharge section to which a sheet bundle detected by the detection means as having been normally bound is discharged; a second discharge section to which a sheet bundle detected by the detection means as not having been bound normally is discharged; A post-processing device comprising:

2. 2. The post-processing device according to claim 1, further comprising a switching means for switching whether to discharge the sheet bundle to the first discharge section or the second discharge section depending on the result of the detection means, in a transport path along which the sheet bundle is transported after the detection means has detected whether the binding process has been performed normally.

3. the first discharge section is a tray that is disposed so as to extend substantially horizontally on an extension of the conveyance path and has an open top, 3. The post-processing device according to claim 2, wherein the second discharge section is a tray that is closed in a substantially box shape and is disposed so as to extend substantially vertically below the transport path and the first discharge section.

4. The binding processing unit performs binding processing using staples, 3. The post-processing device according to claim 1, wherein the detecting means detects the presence or absence of the needle.

5. 5. The post-processing device according to claim 4, wherein when the binding processing unit binds a sheet stack using staples at multiple locations, if the detection means detects that the sheet stack has not been bound properly with any one of the multiple staples, the sheet stack is discharged to the second discharge unit.

6. At least one of the first discharge section and the second discharge section includes a fullness detection sensor that detects a state in which the sheet stack is full, 3. The post-processing device according to claim 1, wherein when the full state of the sheet stack is detected by the full state detection sensor, a notification to that effect is given.

7. 7. The post-processing device according to claim 6, further comprising a limitless discharge mode selectable in which, after the fullness detection sensor detects that the first discharge section is full of sheet bundles, the detection means detects that the sheet bundles have been successfully bound, and the limitless discharge mode discharges the sheet bundles to the second discharge section.

8. The binding processing unit is configured to perform a saddle stitching process for binding a central portion of a sheet bundle as a binding process, a center-folding processing section that folds the center of the sheet bundle that has been subjected to the saddle-stitching processing, 3. The post-processing device according to claim 1, wherein the detection means detects whether or not the sheet bundle after the center-folding process by the center-folding processing section has been properly bound.

9. 3. An image forming system comprising: an image forming apparatus that forms an image on a sheet; and a post-processing apparatus according to claim 1 or 2 that performs post-processing on the sheet on which the image has been formed by the image forming apparatus.

Images