Medium processing device and image forming system

Abstract

To provide a technology for firmly binding a media bundle in a medium processing device that pressure-binds multiple media.SOLUTION: A medium processing device includes a placement part on which media are placed, pressure binding means for applying pressure binding by pressurizing and deforming multiple media placed on the placement part to bind them, and control means for controlling the pressure binding means. When binding N sheets of media, the control means causes the pressure binding means to apply pressure binding at the time when M (smaller than N) sheets of media are placed on the placement part and when N sheets of media are placed on the placement part.SELECTED DRAWING: Figure 15

Description

Technical Field

[0001] The present invention relates to a media processing apparatus and an image forming system.

Background Art

[0002] Conventionally, there is known a media processing apparatus including a stacking tray for stacking a sheet-like medium on which an image is formed by an image forming apparatus, and binding means for binding a plurality of media stacked on the stacking tray into a bundle (hereinafter referred to as a "media bundle").

[0003] Among such media processing apparatuses, from the viewpoint of resource saving and reduction of environmental load, there is a so-called "pressure bonding binding" that can sandwich and pressure-deform a media bundle with uneven binding teeth without using a metal binding needle (see, for example, Patent Document 1).

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, since the binding force by the binding teeth is difficult to be transmitted to the middle of the media bundle, there is a problem that when the number of media constituting the media bundle increases, the pressure-bonded media bundle is likely to be separated afterwards.

[0005] The present invention has been made to solve such problems, and an object thereof is to provide a technique for firmly binding a media bundle in a media processing apparatus that pressure-bonding binds a plurality of media.

Means for Solving the Problems

[0006] In order to solve the above problems, one aspect of the present invention includes a placement unit for placing a medium, a pressure bonding and binding means for performing pressure bonding and binding to pressurize and deform a plurality of the media placed on the placement unit, and a control means for controlling the pressure bonding and binding means. When binding N sheets of the media, the control means causes the pressure bonding and binding means to perform the pressure bonding and binding at the time when M (<N) sheets of the media are placed on the placement unit and at the time when N sheets of the media are placed on the placement unit.

Effect of the Invention

[0007] According to the present invention, in a medium processing apparatus that pressure-bonds and binds a plurality of media, a medium bundle can be firmly bound.

Brief Description of the Drawings

[0008]

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Mode for Carrying Out the Invention

[0009] Hereinafter, the image forming system 1 according to the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing the overall configuration of the image forming system 1. The image forming system 1 has a function of forming an image on a sheet P (a sheet-like medium) and performing post-processing on the sheet P on which the image has been formed. As shown in FIG. 1, the image forming system 1 is composed of an image forming apparatus 2 and a post-processing apparatus 3 (a medium processing apparatus) according to the present invention.

[0010] The image forming apparatus 2 forms an image on the sheet P and discharges the sheet P on which the image has been formed to the post-processing apparatus 3. The image forming apparatus 2 includes a tray in which the sheet P is accommodated, a conveyance unit that conveys the sheet P accommodated in the tray, and an image forming unit that forms an image on the sheet P conveyed by the conveyance unit. The image forming unit may be an inkjet method that forms an image using ink or an electrophotographic method that forms an image using toner. Since the configuration of the image forming apparatus 2 is already well-known, a detailed description will be omitted.

[0011] [First Embodiment of Post-processing Device 3] FIG. 2 is a diagram showing the internal structure of the post-processing device 3 according to the first embodiment. The post-processing device 3 performs post-processing on the sheet P on which an image is formed by the image forming device 2. One of the post-processings according to this embodiment is a binding process as a "pressure binding process" for binding a bundle (sheet bundle) of a plurality of sheets P on which images are formed without using a binding pin. Another post-processing according to this embodiment is a binding process as a "needle binding process" for binding a bundle (sheet bundle) of a plurality of sheets P on which images are formed using a binding pin. Hereinafter, a bundle (media bundle) of a plurality of sheets P is denoted as "sheet bundle Pb".

[0012] More specifically, the "pressure binding process" according to this embodiment is a process of applying pressure to a binding position corresponding to a part of the sheet bundle Pb to deform (press and deform) the binding position for binding, which is a process called "pressure binding". Note that the binding processes executable in the post-processing device 3 include an end binding process for binding the end of the sheet bundle Pb and a middle binding process for binding the central part of the sheet bundle Pb.

[0013] The post-processing device 3 includes conveyance roller pairs 10 to 19 (conveyance means) and a switching claw 20. The conveyance roller pairs 10 to 19 convey the sheet P supplied from the image forming device 2 inside the post-processing device 3. More specifically, the conveyance roller pairs 10 to 13 convey the sheet P along the first conveyance path Ph1. Also, the conveyance roller pairs 14 to 15 convey the sheet P along the second conveyance path Ph2. Further, the conveyance roller pairs 16 to 19 convey the sheet P along the third conveyance path Ph3.

[0014] The first conveyance path Ph1 is a path from the supply port of the sheet P from the image forming device 2 to the discharge tray 21. The second conveyance path Ph2 branches from the first conveyance path Ph1 between the conveyance roller pairs 11 and 14 in the conveyance direction and reaches the discharge tray 26 through the internal tray 22. The third conveyance path Ph3 branches from the first conveyance path Ph1 between the conveyance roller pairs 11 and 14 in the conveyance direction and reaches the discharge tray 30.

[0015] The switching claw 20 is disposed at the branching position between the first conveyance path Ph1 and the second conveyance path Ph2. The switching claw 20 is configured to be switchable between a first position for discharging the sheet P through the first conveyance path Ph1 to the discharge tray 21 and a second position for guiding the sheet P conveyed through the first conveyance path Ph1 to the second conveyance path Ph2. Further, at the timing when the trailing edge of the sheet P that has entered the second conveyance path Ph2 passes through the pair of conveyance rollers 11, the pair of conveyance rollers 14 is rotated reversely, whereby the sheet P is guided to the third conveyance path Ph3. Further, the post-processing device 3 includes a plurality of sensors (indicated by ▲ in FIG. 2) for detecting the position of the sheet P on each of the conveyance paths Ph1, Ph2, and Ph3.

[0016] The post-processing device 3 includes a discharge tray 21. The sheet P discharged through the first conveyance path Ph1 is placed on the discharge tray 21. Sheets P among the sheets P supplied from the image forming apparatus 2 that are not subjected to the binding process are discharged onto the discharge tray 21.

[0017] Further, the post-processing device 3 includes an internal tray 22 (placement section) as a placement tray, an end fence 23, side fences 24L and 24R, an end binding processing section 25, a stitch binding processing section 155, and a discharge tray 26. The internal tray 22, the end fence 23, the side fences 24L and 24R, the end binding processing section 25, and the stitch binding processing section 155 perform an end binding process on a sheet bundle Pb formed by a plurality of sheets P conveyed through the second conveyance path Ph2. The sheet bundle Pb on which the end binding process has been performed among the sheets P supplied from the image forming apparatus 2 is discharged onto the discharge tray 26.

[0018] The “end binding process” as used herein includes a “parallel binding process” in which the binding process is performed along one side parallel to the main scanning direction of the sheet bundle Pb, a “diagonal binding process” in which the binding process is performed at the corner of the sheet bundle Pb, and a “vertical binding process” in which the binding process is performed along one side parallel to the conveyance direction of the sheet bundle Pb.

[0019] Hereinafter, the direction from the pair of conveyance rollers 15 toward the end fence 23 is defined as the "conveyance direction" of the sheet P. That is, the "conveyance direction" in this specification corresponds to the direction in which the sheet P discharged from the image forming apparatus 2 moves in the direction of the discharge tray 26 by the pair of conveyance rollers 10 or the like and then toward the end fence 23 by the pair of conveyance rollers 15. Further, the direction orthogonal to the thickness direction and the conveyance direction of the sheet P is defined as the "main scanning direction (width direction of the sheet P)".

[0020] The plurality of sheets P sequentially conveyed via the second conveyance path Ph2 are temporarily placed on the internal tray 22 as a placement tray. The end fence 23 aligns the positions of the sheets P or the sheet bundle Pb placed on the internal tray 22 in the conveyance direction. The side fences 24L and 24R align the positions of the sheets P or the sheet bundle Pb placed on the internal tray 22 in the main scanning direction. The edge binding processing unit 25 and the stitch binding processing unit 155 perform edge binding processing on the ends of the sheet bundle Pb aligned by the end fence 23 and the side fences 24L and 24R. Then, the pair of conveyance rollers 15 discharges the sheet bundle Pb subjected to the edge binding processing to the discharge tray 26.

[0021] Furthermore, the post-processing apparatus 3 further includes an end fence 27, a middle binding processing unit 28, a sheet folding blade 29, and a discharge tray 30. The end fence 27, the middle binding processing unit 28, and the sheet folding blade 29 perform middle binding processing on the sheet bundle Pb composed of the plurality of sheets P conveyed through the third conveyance path Ph3. The sheet bundle Pb subjected to the middle binding processing among the sheets P supplied from the image forming apparatus 2 is discharged to the discharge tray 30.

[0022] The end fence 27 aligns the positions of a plurality of sheets P conveyed in sequence in the third conveyance path Ph3 in the conveyance direction. Further, the end fence 27 is configured to be movable to a binding position where the center of the sheet bundle Pb faces the middle binding processing unit 28 and a folding position where it faces the sheet folding blade 29. The middle binding processing unit 28 binds the center of the sheet bundle Pb aligned by the end fence 27 at the binding position. The sheet folding blade 29 folds the sheet bundle Pb placed on the end fence 27 at the folding position in half and sandwiches it between the pair of conveyance rollers 18. The pairs of conveyance rollers 18 and 19 discharge the sheet bundle Pb subjected to the middle binding process to the discharge tray 30.

[0023] [Detailed description of the end binding processing unit 25] FIG. 3 is a schematic view of the end binding processing unit 25 that performs liquid application and pressure binding processing as viewed from the upstream side in the conveyance direction. FIG. 4 is a schematic view of the end binding processing unit 25 as viewed from the liquid application unit 31 side in the main scanning direction. As shown in FIGS. 3 and 4, the end binding processing unit 25 includes a liquid application unit 31 (liquid application means) that executes a processing operation related to liquid application, and a pressure binding unit 32 (pressure binding means) that is an example of post-processing means and performs pressure binding processing. The liquid application unit 31 and the pressure binding unit 32 are arranged adjacent to each other in the main scanning direction on the downstream side in the conveyance direction from the internal tray 22.

[0024] The liquid application unit 31 applies the liquid stored in the liquid storage tank 43 to the sheet P or the sheet bundle Pb placed on the internal tray 22. Hereinafter, applying liquid to the sheet P or the sheet bundle Pb is referred to as "liquid application", and the process for performing liquid application is referred to as "liquid application process".

[0025] Here, for liquid application, the liquid stored in the liquid storage tank 43 is, more specifically, mainly composed of the liquid state of a compound of hydrogen and oxygen represented by the chemical formula "H 2 O". As long as it is in a liquid state, its temperature state does not matter, and it may be so-called warm water or hot water. Also, not limited to pure water, purified water is of course acceptable, and it may contain ionized salts. The metal ion content may have any hardness from so-called soft water to super hard water.

[0026] In addition to the main components, additives may be added. It may contain residual chlorine used as tap water, or it is also desirable that preservatives such as coloring agents, penetrants, pH adjusters, phenoxyethanol, and drying inhibitors such as glycerin are added. Furthermore, since ink used in an inkjet printing device and ink used in a water-based pen also use water as a component, this may be used as "liquid application".

[0027] Not limited to those specifically mentioned here, "water" in a broad sense such as hypochlorous acid water or an ethanol aqueous solution diluted for disinfection also functions, but tap water that is easy to obtain and manage may be used for applications only for the purpose of enhancing the binding strength after binding treatment. Also, as the liquid, using a liquid mainly composed of water as exemplified above can improve the binding strength of the paper bundle Pb compared to using a liquid not mainly composed of water.

[0028] [Configuration of Liquid Application Unit 31 and Crimping Unit 32] Both the liquid application unit 31 and the crimping unit 32 are configured to be movable in the main scanning direction by the driving force of the end-binding processing unit moving motor 50 being transmitted. The position (liquid application position) where liquid application is performed on the paper P or the paper bundle Pb by the liquid application unit 31 corresponds to the position (crimping binding position) where crimping binding is to be performed by the crimping unit 32. Therefore, in the following description, the same reference numerals are given to the liquid application position and the crimping binding position.

[0029] As shown in FIGS. 3 and 4, the liquid application unit 31 is configured to be movable in the main scanning direction together with the crimping unit 32 by the driving force of the end-binding processing unit moving motor 50 being transmitted. The liquid application unit 31 includes a lower pressing plate 33 as a mounting table for the paper P or the paper bundle Pb, an upper pressing plate 34, a liquid application unit moving mechanism 35, and a liquid application mechanism 36. The component parts (lower pressing plate 33, upper pressing plate 34, liquid application unit moving mechanism 35, liquid application mechanism 36) of the liquid application unit 31 are held by a liquid application frame 31a and a base member 48.

[0030] The lower pressing plate 33 and the upper pressing plate 34 are arranged on the downstream side in the conveyance direction from the internal tray 22. The sheet P or the stack of sheets Pb placed on the internal tray 22 is also placed on the lower pressing plate 33. The lower pressing plate 33 is provided on the lower pressing plate holder 331. The upper pressing plate 34 is configured to be movable in the thickness direction of the sheet P or the stack of sheets Pb at a position facing the sheet P or the stack of sheets Pb placed on the internal tray 22. That is, the lower pressing plate 33 and the upper pressing plate 34 are arranged to face each other in the thickness direction of the sheet P or the stack of sheets Pb so as to sandwich the sheet P or the stack of sheets Pb placed on the internal tray 22 in the space where they face each other. Hereinafter, the thickness direction of the sheet P or the stack of sheets Pb will be simply referred to as the "thickness direction". Further, a through hole 34a penetrating in the thickness direction is formed in the upper pressing plate 34 at a position facing the tip of the liquid application member 44 held via the joint 46 attached to the base plate 40.

[0031] The liquid application unit moving mechanism 35 moves the upper pressing plate 34, the base plate 40, and the liquid application member 44 in the thickness direction of the sheet P or the stack of sheets Pb. The liquid application unit moving mechanism 35 according to the present embodiment moves the upper pressing plate 34, the base plate 40, and the liquid application member 44 in conjunction with a single liquid application unit moving motor 37. The liquid application unit moving mechanism 35 includes, for example, a liquid application unit moving motor 37, a trapezoidal screw 38, a nut 39, a base plate 40, columnar members 41a and 41b, and coil springs 42a and 42b.

[0032] The liquid application unit moving motor 37 generates a driving force for moving the upper pressing plate 34, the base plate 40, and the liquid application member 44. The trapezoidal screw 38 extends in the thickness direction of the sheet P or the stack of sheets Pb and is rotatably attached to the liquid application frame 31a in the forward and reverse directions. The trapezoidal screw 38 is also connected to the output shaft of the liquid application unit moving motor 37 via a pulley, a belt, or the like. The nut 39 is screwed onto the trapezoidal screw 38. Then, when the driving force of the liquid application unit moving motor 37 is transmitted and the trapezoidal screw 38 rotates in the forward and reverse directions, the nut 39 reciprocates on the trapezoidal screw 38.

[0033] Further, the base plate 40 is disposed at a position spaced apart from the upper pressing plate 34. The base plate 40 holds the liquid application member 44 in a state where the tip of the liquid application member 44 protrudes from the base plate 40 toward the upper pressing plate 34. Further, the base plate 40 is connected to the trapezoidal screw 38 via the nut 39, and is configured to be reciprocally movable along the trapezoidal screw 38 as the trapezoidal screw 38 rotates in the forward and reverse directions. Then, the position of the base plate 40 in the thickness direction of the sheet P or the sheet bundle Pb is detected by a movement sensor 40a (see FIG. 10).

[0034] The columnar members 41a and 41b protrude from the base plate 40 toward the upper pressing plate 34 around the tip of the liquid application member 44. The columnar members 41a and 41b are configured to be relatively movable in the thickness direction with respect to the base plate 40. Further, the columnar members 41a and 41b hold the upper pressing plate 34 at the tips on the lower pressing plate 33 side. Further, at the tips of the columnar members 41a and 41b on the side opposite to the lower pressing plate 33, there are provided stoppers for preventing the columnar members 41a and 41b from coming off the base plate 40. The coil springs 42a and 42b are externally inserted into the columnar members 41a and 41b between the base plate 40 and the upper pressing plate 34. The coil springs 42a and 42b bias the upper pressing plate 34 and the columnar members 41a and 41b toward the lower pressing plate 33 side with respect to the base plate 40.

[0035] The liquid application mechanism 36 applies liquid to the sheet P or the sheet bundle Pb placed on the inner tray 22. More specifically, the liquid application mechanism 36 applies liquid to at least one sheet P constituting the sheet bundle Pb by bringing the tip of the liquid application member 44 into contact with the sheet P or the sheet bundle Pb. The liquid application mechanism 36 includes a liquid storage tank 43, a liquid application member 44, a liquid supply member 45, and a joint 46.

[0036] The liquid storage tank 43 stores a liquid for supplying the paper P or the paper bundle Pb. The amount of the liquid stored in the liquid storage tank 43 is detected by the liquid level sensor 43a. The liquid application member 44 applies the liquid stored in the liquid storage tank 43 to the paper P or the paper bundle Pb. The liquid application member 44 is attached to the base plate 40 with its tip facing the upper pressing plate 34 side. Further, the liquid application member 44 is made of a porous material with a high liquid absorption rate or a fiber material that can suck up the liquid by capillary action. The liquid application member 44 is a material having the property of sucking up and holding the liquid, and any type may be used as long as it has the property of being crushed according to the pressing force applied in the state of being in contact with the paper P. For example, it may be a foam such as a sponge or a fiber that can suck up the liquid by capillary action.

[0037] The liquid supply member 45 is a long member with its base end immersed in the liquid stored in the liquid storage tank 43 and its tip end connected to the liquid application member 44. Further, the liquid supply member 45 is made of a material with a high water absorption rate, for example, similar to the liquid application member 44. Thereby, the liquid absorbed from the base end of the liquid supply member 45 is supplied to the liquid application member 44 through the liquid supply member 45 by capillary action. In the above description, the case where the liquid application member 44 and the liquid supply member 45 are separately configured has been described, but the liquid application member 44 and the liquid supply member 45 may be integrally configured with a material having the same properties. Even in this case, the liquid stored in the liquid storage tank 43 can be sucked up by capillary action in the same manner as the above description, and the cost can be reduced.

[0038] The protective member 45a is a long cylindrical body (e.g., a tube) that is externally inserted into the liquid supply member 45. The protective member 45a is a member for preventing the liquid absorbed by the liquid supply member 45 from leaking or evaporating. Further, the liquid supply member 45 and the protective member 45a are formed of a flexible material. The joint 46 fixes the liquid application member 44 to the base plate 40. As a result, even when the liquid application member 44 is moved by the liquid application unit movement mechanism 35, it protrudes from the base plate 40 toward the upper pressing plate 34 side, and the state where the tip faces downward is maintained.

[0039] Further, a liquid application frame 31a that holds the components of the liquid application unit 31 has a liquid application unit rotating shaft 562 provided with a drive transmission gear 562a fixed to its bottom surface. The liquid application unit rotating shaft 562 and the drive transmission gear 562a are rotatably held in the forward and reverse directions by a base member 48 on which the liquid application frame 31a is provided. Further, the drive transmission gear 562a meshes with an output gear 563a of a liquid application unit rotation motor 563. Then, the liquid application unit 31 is configured to be rotatable in the forward and reverse directions around the liquid application unit rotating shaft 562 on the base member 48 by the driving force of the liquid application unit rotation motor 563 being transmitted to the liquid application unit rotating shaft 562 via the output gear 563a and the drive transmission gear 562a.

[0040] The crimping unit 32 (post-processing means) binds the paper bundle Pb by sandwiching and pressing at least a part (i.e., the liquid application position) of the paper bundle Pb to which liquid has been applied by the liquid application unit 31 with the uneven upper crimping teeth 32a and the lower crimping teeth 32b to deform it. Hereinafter, the process and operation of deforming and binding at least a part of the paper bundle Pb by sandwiching and pressing with the upper crimping teeth 32a and the lower crimping teeth 32b will be referred to as "crimping binding". That is, the crimping unit 32 can bind the paper bundle Pb without using a binding member such as a binding needle. The components (the upper crimping teeth 32a and the lower crimping teeth 32b) of the crimping unit 32 are provided on a crimping frame 32c.

[0041] FIG. 5 is a schematic diagram showing the configuration of the crimping portion 32. As shown in FIG. 5, the crimping portion 32 includes a pair of binding teeth (upper crimping teeth 32a and lower crimping teeth 32b). The upper crimping teeth 32a and the lower crimping teeth 32b are arranged to face each other in the thickness direction of the paper bundle Pb so as to sandwich the paper bundle Pb placed on the inner tray 22. The surfaces of the upper crimping teeth 32a and the lower crimping teeth 32b facing each other are formed in an uneven shape in which concave portions and convex portions are alternately formed. Further, the upper crimping teeth 32a and the lower crimping teeth 32b are formed such that the concave portions and the convex portions are displaced so as to mesh with each other.

[0042] Further, the uneven upper crimping teeth 32a and lower crimping teeth 32b have inclined portions at an arbitrary angle. Also, the shapes of the apex portions and valley portions of the uneven shape are different between the upper crimping teeth 32a and the lower crimping teeth 32b. More specifically, the tooth height (distance from the apex portion to the valley portion) of the upper crimping teeth 32a is lower than the tooth height of the lower crimping teeth 32b. As a result, when the upper crimping teeth 32a and the lower crimping teeth 32b are engaged, the apex portion of the upper crimping teeth 32a and the valley portion of the lower crimping teeth 32b do not come into contact with each other. Therefore, the paper P pressed by the upper crimping teeth 32a and the lower crimping teeth 32b is crushed and extended at the inclined surface portion and escapes into the gap between the apex portion of the upper crimping teeth 32a and the valley portion of the lower crimping teeth 32b. As a result, it is possible to crimp the paper bundle Pb only with the inclined surface portion (generate a deviation between the papers and entangle and fix the fibers), and it becomes possible to perform the crimp binding efficiently.

[0043] Then, the upper crimping teeth 32a and the lower crimping teeth 32b are separated and contacted by the driving force of the contact / separation motor 32d (see FIG. 10). In the process in which a plurality of papers P constituting the paper bundle Pb are supplied to the inner tray 22, as shown in FIG. 5(A), the upper crimping teeth 32a and the lower crimping teeth 32b are separated from each other. Then, when all the papers P constituting the paper bundle are placed on the inner tray 22, as shown in FIG. 5(B), the upper crimping teeth 32a and the lower crimping teeth 32b are engaged with each other, and the paper bundle Pb is pressure-deformed from the thickness direction. Thereby, the paper bundle Pb placed on the inner tray 22 is crimp-bound. Further, the crimp-bound paper bundle Pb is discharged to the discharge tray 26 by the pair of conveying rollers 15.

[0044] FIG. 6 is a diagram showing a contact / separation mechanism 90 for separating and contacting the upper crimping teeth 32a and the lower crimping teeth 32b. The contact / separation mechanism 90 is a mechanism for separating and contacting the upper crimping teeth 32a and the lower crimping teeth 32b by the driving force of a contact / separation motor 32d. As shown in FIG. 6, for example, the contact / separation mechanism 90 mainly includes an upper arm 91, a lower arm 92, a coil spring 93 (biasing member), a driving gear 94, a driven gear 95, and an eccentric cam 96.

[0045] The upper arm 91 is fixed to the crimping frame 32c. Further, the upper arm 91 supports the upper crimping teeth 32a. The lower arm 92 is supported by the upper arm 91 so as to be rotatable around a rotation shaft 97. Further, the lower arm 92 supports the lower crimping teeth 32b at one end (the end facing the upper crimping teeth 32a). Then, as the lower arm 92 rotates around the rotation shaft 97, the upper crimping teeth 32a and the lower crimping teeth 32b come into contact and separate. The coil spring 93 biases the lower arm 92 in a direction to separate the upper crimping teeth 32a and the lower crimping teeth 32b. The driving gear 94 rotates by the driving force of the contact / separation motor 32d. The driven gear 95 is meshed with the driving gear 94. The eccentric cam 96 is connected to the driven gear 95 at a position offset from the center and rotates integrally with the driven gear 95. Further, the outer peripheral surface of the eccentric cam 96 abuts on the other end of the lower arm 92 (the end on the side opposite to the side supporting the lower crimping teeth 32b with the rotation shaft 97 interposed therebetween).

[0046] When the eccentric cam 96 is in the state of FIG. 6(A), the upper crimping teeth 32a and the lower crimping teeth 32b are separated by the biasing force of the coil spring 93. Further, when the eccentric cam 96 rotates from the state of FIG. 6(A), the lower arm 92 rotates in a direction to bring the upper crimping teeth 32a and the lower crimping teeth 32b into contact against the biasing force of the coil spring 93. Then, when the eccentric cam 96 is in the state of FIG. 6(B), the upper crimping teeth 32a and the lower crimping teeth 32b mesh. Further, when the eccentric cam 96 rotates from the state of FIG. 6(B), the lower arm 92 rotates in a direction to separate the upper crimping teeth 32a and the lower crimping teeth 32b by the biasing force of the coil spring 93.

[0047] Furthermore, as for the configuration of the crimping portion 32, since the upper crimping teeth 32a and the lower crimping teeth 32b constituting the crimping mechanism only need to mesh with each other, it is not limited to the embodiments described above. For example, a link mechanism type crimping mechanism (for example, the one disclosed in Japanese Patent No. 6057167) that performs the crimping and separating operations of the upper crimping teeth 32a and the lower crimping teeth 32b using only a forward rotation or a drive source that rotates forward and backward and a link mechanism may be used, or a linear motion type crimping mechanism that linearly performs the crimping (approaching) and separating operations of the upper crimping teeth 32a and the lower crimping teeth 32b by a screw mechanism that converts the rotational motion of the drive source in the forward and reverse directions into a linear reciprocating motion may also be used.

[0048] Also, a crimping frame 32c that holds the components of the crimping portion 32 has a crimping portion rotation shaft 54 provided with a drive transmission gear 54a fixed to its bottom surface. The crimping portion rotation shaft 54 and the drive transmission gear 54a are rotatably held in the forward and reverse directions by a base member 48 where the crimping frame 32c is provided. Further, the drive transmission gear 54a meshes with an output gear 56a of a crimping portion rotation motor 56. Then, the crimping portion 32 is configured to be rotatable in the forward and reverse directions around the crimping portion rotation shaft 54 on the base member 48 when the driving force of the crimping portion rotation motor 56 is transmitted to the crimping portion rotation shaft 54 via the output gear 56a and the drive transmission gear 54a.

[0049] Also, as shown in FIG. 3, the binding process unit 25 includes an end binding process unit movement mechanism 47. The end binding process unit movement mechanism 47 moves the binding process unit 25 (that is, the liquid application unit 31 and the crimping unit 32) in the main scanning direction along the downstream end of the paper P placed on the inner tray 22 in the conveyance direction. The end binding process unit movement mechanism 47 includes, for example, a base member 48, a guide shaft 49, an end binding process unit movement motor 50, and a driving force transmission mechanism 551.

[0050] The liquid application unit 31 and the crimping unit 32 are attached to the base member 48 in a state of being adjacent to each other in the main scanning direction. The guide shaft 49 extends in the main scanning direction on the downstream side in the conveyance direction from the internal tray 22. Further, the guide shaft 49 supports the base member 48 so as to be movable in the main scanning direction. The end-binding process unit moving motor 50 generates a driving force for moving the binding process unit 25. The driving force transmission mechanism 551 transmits the driving force of the end-binding process unit moving motor 50 to the base member 48 via pulleys 551a, 551b, and a timing belt 551c. Thereby, the liquid application unit 31 and the crimping unit 32 integrated by the base member 48 move in the main scanning direction along the guide shaft 49.

[0051] That is, as shown in FIG. 12(A), the standby position HP is a position deviated in the width direction from the sheet P placed on the internal tray 22. Further, as shown in FIGS. 12(B) to 12(C), the liquid application unit 31 and the crimping unit 32 can move along the guide shaft 49 to a position where they can face the sheet P placed on the internal tray 22 in the thickness direction of the sheet P.

[0052] The end-binding process unit moving motor 50 according to the present embodiment is, for example, a servo motor that can stop the end-binding process unit 25 at a target position (binding position B) without returning the end-binding process unit 25 to the origin position (for example, the standby position HP described later) every time it moves.

[0053] Further, the post-processing device 3 includes an end-binding standby position sensor 51 (for example, a light-shielding type optical sensor; see FIG. 10) that detects that the end-binding process unit 25 has reached the standby position HP (see FIG. 12), and an encoder sensor 541 (see FIG. 10) attached to the output shaft of the end-binding process unit moving motor 50. Then, a controller 100 described later detects that the end-binding process unit 25 has reached the standby position HP based on the detection result of the end-binding standby position sensor 44a. Further, the controller 100 grasps the current position of the end-binding process unit 25 that has moved from the standby position HP by counting the pulse signal output from the encoder sensor 541.

[0054] However, the specific method of stopping the edge binding processing unit 25 at the target position without returning it to the origin position is not limited to the foregoing example. As another example, the post-processing device 3 may include a sensor that detects that the edge binding processing unit 25 has reached a predetermined target position.

[0055] [Modification example of the edge binding processing unit 25] Next, with reference to FIGS. 7 to 9, a modification example of the edge binding processing unit 25 provided in the post-processing device 3, i.e., an edge binding processing unit 25' as a post-processing means, will be described. The difference from the edge binding processing unit 25 already described is that the liquid application unit 31 and the pressure bonding unit 32 are integrally configured. Note that the same reference numerals are assigned to the common components as those of the edge binding processing unit 25 already described, and detailed descriptions may be omitted.

[0056] FIG. 7 is a schematic view of the edge binding processing unit 25' as viewed from the upstream side in the transport direction. FIG. 8(A) is a perspective view of the liquid application and pressure bonding unit 310. FIG. 8(B) is a cross-sectional view taken along the line A-A of FIG. 8(A). FIG. 8(C) is a plan view of the upper pressure bonding teeth 32a of FIG. 8(A) as viewed from a direction where the lower pressure bonding teeth 32b are located. FIGS. 9(A) to 9(C) are views showing the liquid application operation and the pressure bonding operation by the liquid application and pressure bonding unit 310, and are schematic views as viewed from the downstream side in the transport direction.

[0057] As shown in FIG. 7, the edge binding processing unit 25' includes a liquid application and pressure bonding unit 310 that integrally configures the liquid application unit 31 and the pressure bonding unit 32 of the edge binding processing unit 25 according to the first embodiment. The liquid application and pressure bonding unit 310 is disposed on the downstream side in the transport direction from the internal tray 22.

[0058] The liquid application and crimping unit 310 applies the liquid LQ stored in the liquid storage tank 43 to the paper P or the paper bundle Pb placed on the inner tray 22. The liquid application and crimping unit 310 is configured to be movable in the main scanning direction by the driving force of the end binding process unit moving motor 50 being transmitted to the base member 48 by the driving force transmission mechanism 551. The liquid application and crimping unit 310 includes an upper pressing plate 34, upper crimping teeth 32a, lower crimping teeth 32b, a liquid application and crimping unit moving mechanism 350, and a liquid supply mechanism 360. Each component of the liquid application and crimping unit 310 is held by the liquid application frame 31a and the base member 48. Further, a liquid application and crimping unit rotating shaft 54' provided with a driving transmission gear 54a' is fixed to the bottom surface of the liquid application frame 31a. The liquid application and crimping unit rotating shaft 54' and the driving transmission gear 54a' are rotatably held in the forward and reverse directions by the base member 48 provided with the liquid application frame 31a. Further, the driving transmission gear 54a' meshes with the output gear 56a' of the liquid application and crimping unit rotation motor 56'. Then, the liquid application and crimping unit 310 is configured to be rotatable in the forward and reverse directions around the liquid application and crimping unit rotating shaft 54' on the base member 48 by the driving force of the liquid application and crimping unit rotation motor 56' being transmitted to the liquid application and crimping unit rotating shaft 54' via the output gear 56a' and the driving transmission gear 54a'.

[0059] The liquid application and crimping unit moving mechanism 350 moves the upper pressing plate 34, the base plate 40, and the upper crimping teeth 32a in conjunction with each other in the thickness direction of the paper P or the paper bundle Pb by means of an electric cylinder 370. The base plate 40 holds the upper crimping tooth holding member 32a1 and the upper crimping teeth 32a via a joint 46. Further, the base plate 40 movably holds the upper pressing plate 34 via columnar members 41a, 41b. Then, the base plate 40 is attached to the tip of the rod 371 of the electric cylinder 370 via a connecting member 401.

[0060] The columnar members 41a and 41b hold the upper pressing plate 34 at their lower ends. Also, the coil springs 42a and 42b are externally inserted into the columnar members 41a and 41b between the base plate 40 and the upper pressing plate 34. And the coil springs 42a and 42b bias the upper pressing plate 34 and the columnar members 41a and 41b in a direction away from the base plate 40.

[0061] The liquid supply mechanism 360 includes a liquid storage tank 43, a liquid supply pump 431, and a liquid supply member 45. The liquid supply pump 431 supplies the liquid LQ to a liquid reservoir portion 320 provided in the upper crimping tooth holding member 32a1 as shown in FIG. 8(A) via the liquid supply member 45. The liquid supply member 45 has a proximal end connected to the liquid supply pump 431 and a distal end connected to the liquid reservoir portion 320, and is composed of a long and stretchable member.

[0062] As shown in FIG. 8(B), the upper crimping tooth 32a is integrally provided on the upper crimping tooth holding member 32a1. And the upper crimping tooth holding member 32a1 includes a liquid reservoir portion 320 and a liquid supply passage 321 that supplies the liquid LQ stored in the liquid reservoir portion 320 to the upper crimping tooth 32a. Also, the surface of the upper crimping tooth 32a is subjected to a hydrophilic treatment so that the liquid LQ supplied from the liquid supply passage 321 spreads uniformly over the surface of the upper crimping tooth 32a. On the other hand, the portion of the upper crimping tooth holding member 32a1 other than the upper crimping tooth 32a is subjected to a hydrophobic treatment so that the liquid LQ spreads efficiently over the surface of the upper crimping tooth 32a.

[0063] As shown in FIG. 7, the lower crimping tooth 32b is integrally provided on the lower crimping tooth holding member 32b1 which is a part of the liquid application frame 31a, and is attached onto the base member 48 via the lower crimping tooth holding member 32b1.

[0064] Next, the liquid application operation and the pressure-bonding binding operation by the liquid application and pressure-bonding unit 310 will be described with reference to FIG. 9. In the process of supplying the paper P to the inner tray 22, as shown in FIG. 9(A), the upper pressure-bonding teeth 32a and the lower pressure-bonding teeth 32b are separated. Then, when the paper P is placed on the inner tray 22, the electric cylinder 370 is contracted to move the upper pressure-bonding teeth 32a and the upper pressing plate 34 toward the paper P. Then, as shown in FIG. 9(B), the upper pressing plate 34 first contacts the paper P, and then the upper pressure-bonding teeth 32a pass through the through-hole 34a of the upper pressing plate 34 and contact the paper P. At this time, since the liquid LQ is spread on the surface of the upper pressure-bonding teeth 32a, the liquid is applied to the liquid application position of the paper P by bringing the upper pressure-bonding teeth 32a into contact with the paper P. Then, when the liquid application to the liquid application position is completed, the electric cylinder 370 is extended to separate the upper pressure-bonding teeth 32a and the upper pressing plate 34 from the paper P. Since the contact and separation operation of the upper pressure-bonding teeth 32a and the upper pressing plate 34 with respect to the paper P described above corresponds to the liquid application operation, this liquid application operation is repeatedly executed for the paper P constituting the paper bundle Pb.

[0065] After that, when the paper bundle Pb composed of the specified number of papers P is placed on the inner tray 22, the electric cylinder 370 is further contracted to move the upper pressure-bonding teeth 32a toward the lower pressure-bonding teeth 32b. Then, as shown in FIG. 9(C), with the paper bundle Pb sandwiched between the upper pressure-bonding teeth 32a and the lower pressure-bonding teeth 32b, the upper pressure-bonding teeth 32a further move toward the lower pressure-bonding teeth 32b, and the paper bundle Pb is pressure-bonded and bound by pressing and deforming the paper bundle Pb with the upper pressure-bonding teeth 32a and the lower pressure-bonding teeth 32b (pressure-bonding binding operation).

[0066] [Control Block of Post-processing Device 3] FIG. 10 is a hardware configuration diagram of the post-processing device 3. As shown in FIG. 10, the post-processing device 3 includes a configuration in which a CPU (Central Processing Unit) 101, a RAM (Random Access Memory) 102, a ROM (Read Only Memory) 103, an HDD (Hard Disk Drive) 104, and an I / F 105 are connected via a common bus 109.

[0067] The CPU 101 is an arithmetic unit that controls the operation of the entire post-processing device 3. The RAM 102 is a volatile storage medium that enables high-speed reading and writing of information and is used as a work area when the CPU 101 processes information. The ROM 103 is a non-volatile storage medium for read-only use, in which programs such as firmware are stored. The HDD 104 is a non-volatile storage medium that enables reading and writing of information and has a large storage capacity, in which an OS (Operating System), various control programs, application programs, etc. are stored.

[0068] The post-processing device 3 processes, by means of the arithmetic function provided by the CPU 101, control programs stored in the ROM 103, information processing programs (application programs) loaded from storage media such as the HDD 104 to the RAM 102, etc. By this processing, software control means including various functional modules of the post-processing device 3 is configured. A functional block that realizes the functions of the post-processing device 3 is configured by the combination of the software control means configured in this way and the hardware resources mounted on the post-processing device 3. That is, the CPU 101, the RAM 102, the ROM 103, and the HDD 104 constitute a controller 100 (corresponding to control means) that controls the operation of the post-processing device 3.

[0069] I / F 105 is an interface that connects the conveyance roller pairs 10, 11, 14, 15, the switching claws 20, the side fences 24L, 24R, the contact / separation motor 32d, the crimping part rotation motor 56, the liquid application part movement motor 37, the liquid application part rotation motor 563, the end binding processing part movement motor 50, the needle binding part drive motor 62d, the needle binding means rotation motor 82, the needle binding processing part movement motor 80, the movement sensor 40a, the liquid amount sensor 43a, the standby position sensor 51, the encoder sensor 541, and the operation panel 110 to the common bus 109. The controller 100 controls the operations of the conveyance roller pairs 10, 11, 14, 15, the switching claws 20, the side fences 24L, 24R, the contact / separation motor 32d, the crimping part rotation motor 56, the liquid application part movement motor 37, the liquid application part rotation motor 563, the end binding processing part movement motor 50, the needle binding part drive motor 62d, the needle binding means rotation motor 82, and the needle binding processing part movement motor 80 through the I / F 105.

[0070] Also, the controller 100 acquires the detection results of the movement sensor 40a, the liquid amount sensor 43a, the standby position sensor 51, and the encoder sensor 541. Although FIG. 10 shows only the components related to the end binding processing part 25 that executes the end binding processing and the needle binding processing part 155, the components related to the middle binding processing part 28 that executes the middle binding processing are similarly controlled by the controller 100.

[0071] As shown in FIG. 1, the image forming apparatus 2 includes an operation panel 110. The operation panel 110 includes an operation part that receives an input operation from an operator and a display (notification part) that notifies information to the operator. The operation part includes, for example, hard keys, a touch panel superimposed on the display, and the like. Then, the operation panel 110 acquires information from the operator through the operation part and provides information to the operator through the display. Note that a specific example of the notification part is not limited to a display, and an LED lamp, a speaker, or the like may also be used. Also, the operator includes a so-called "worker" who is responsible for the manufacture and maintenance of the post-processing apparatus 3 and a so-called "user" who uses the post-processing apparatus 3. Further, the post-processing apparatus 3 may be provided with the same operation panel 110 as described above.

[0072] [Explanation of Binding Process] Next, the flow of the binding process executed in the edge binding processing unit 25 provided in the post-processing apparatus 3 will be described. FIG. 11 is a flowchart of the binding process. FIG. 12 is a diagram showing the positions of the liquid application unit 31 and the crimping unit 32 during the binding process. Note that in FIG. 12, the change in the posture of the liquid application unit 31 and the crimping unit 32 is not shown. Further, the position (liquid application position) where the liquid is applied to the sheet P or the sheet bundle Pb by the liquid application unit 131 corresponds to the binding position where the crimping unit 32 is scheduled to perform crimp binding on the sheet bundle Pb. Therefore, in the following, the liquid application position and the binding position will be described with the same reference numerals.

[0073] The controller 100 starts the binding process shown in FIG. 11, for example, at the timing when an execution instruction for the binding process (hereinafter referred to as the "binding process instruction") is acquired from the image forming apparatus 2.

[0074] The binding process instruction includes, for example, the type of the sheet P (information such as the material and thickness that affects the spread of the liquid), the number of sheets P constituting the sheet bundle Pb (hereinafter referred to as the "predetermined number"), the number of sheet bundles Pb to be subjected to the binding process (hereinafter referred to as the "required number"), the binding position of the sheet bundle Pb, and the binding posture of the edge binding processing unit 25. Further, the liquid application unit 31 and the crimping unit 32 are assumed to be in the standby position HP (FIG. 12(A)) which is in the parallel binding posture and is located at a position deviated in the width direction from the sheet P placed on the internal tray 22 at the start time of the binding process.

[0075] First, when the posture instructed by the binding process instruction is the "diagonal binding posture", the controller 100 drives the liquid application unit rotation motor 563 and the crimping unit rotation motor 56 to rotate the liquid application unit 31 and the crimping unit 32 that constitute the edge binding process unit 25 to the diagonal binding posture. Incidentally, when it is in the "diagonal binding posture", only the crimping unit 32 may be rotated to the diagonal binding posture and the liquid application unit 31 may not be rotated. Thereby, compared with the case where both the liquid application unit 31 and the crimping unit 32 are rotated in the forward and reverse directions, the drive mechanism can be simplified, so that effects such as cost reduction, downsizing of the apparatus, and reduction of equipment failures can be achieved.

[0076] On the other hand, when the posture instructed by the binding process instruction is the "parallel binding posture", the controller 100 omits the operation of rotating the liquid application unit 31 and the crimping unit 32 that constitute the edge binding process unit 25 described above to the diagonal binding posture. Further, as shown in FIG. 12(B), the controller 100 drives the edge binding process unit movement motor 50 to move the edge binding process unit 25 in the main scanning direction so that the liquid application unit 31 faces the liquid application position B instructed by the binding process instruction (S1301). The controller 100 executes the process of step S1301 before the first sheet P is conveyed to the internal tray 22 by the conveyance roller pairs 10, 11, 14, 15.

[0077] Next, the controller 100 rotates the conveyance roller pairs 10, 11, 14, 15 to accommodate the sheet P on which an image is formed by the image forming apparatus 2 in the internal tray 22 (S1302). Further, the controller 100 moves the side fences 24L, 24R to align the positions of the sheet bundle Pb placed on the internal tray 22 in the main scanning direction (so-called jogging) (S1302).

[0078] Next, the controller 100 causes the liquid application unit 31 facing the liquid application position B of the sheet P placed on the inner tray 22 in the immediately preceding step S1302 to perform liquid application based on the pre-adjusted liquid application control data (S1303). That is, the controller 100 drives the liquid application unit movement motor 37 to bring the liquid application member 44 into contact with the liquid application position B of the sheet P placed on the inner tray 22 (FIG. 12(B)).

[0079] More specifically, the controller 100 reads out the liquid application amount represented by the liquid application level corresponding to the type of the sheet P indicated by the binding process instruction from the HDD 104. Then, in step S1303, the controller 100 causes the liquid application unit 31 to apply the liquid of the read liquid application amount to the binding position of the sheet P. That is, the controller 100 causes the liquid application unit 31 to apply the liquid of the liquid application amount input through the liquid application amount setting screen described later to the binding position of the sheet P placed on the inner tray 22.

[0080] Next, the controller 100 determines whether or not the number of sheets P accommodated in the inner tray 22 has reached the predetermined number indicated by the binding process instruction (S1304). If the controller 100 determines that the number of sheets P accommodated in the inner tray 22 has not reached the predetermined number (S1304: No), the controller 100 executes the processes of steps S1302 to S1303 again. That is, the controller 100 executes the processes of steps S1302 to S1303 each time the sheet P is conveyed to the inner tray 22 by the conveying roller pairs 10, 11, 14, and 15. However, the liquid application by the liquid application unit 31 may be performed not only on all of the plurality of sheets P constituting the sheet bundle Pb but also on only some of the sheets P. For example, the controller 100 may cause the liquid application unit 31 to apply liquid to the sheet P at an interval of one sheet per n sheets.

[0081] When the controller 100 determines that the number of sheets P accommodated in the inner tray 22 has reached a predetermined number (S1304: Yes), as shown in FIG. 12(C), the controller 100 drives the end-binding processing unit moving motor 50 to move the binding processing unit 25 in the main scanning direction so that the crimping unit 32 faces the binding position B (S1305).

[0082] Next, the controller 100 causes the crimping unit 32 to perform crimp binding on the stack of sheets Pb placed on the inner tray 22 (S1306). Then, the controller 100 discharges the stack of sheets Pb crimp-bound by the crimping unit 32 to the discharge tray 26 by the pair of transport rollers 15 (S1307). That is, the controller 100 drives the contact / separation motor 32d to sandwich the binding position B of the stack of sheets Pb placed on the inner tray 22 between the upper crimping teeth 32a and the lower crimping teeth 32b. Thereby, the stack of sheets Pb is pressure-deformed between the upper crimping teeth 32a and the lower crimping teeth 32b to perform pressure binding. After that, the controller 100 discharges the crimp-bound stack of sheets Pb to the discharge tray 26 by rotating the pair of transport rollers 15.

[0083] Note that on the stack of sheets Pb placed on the inner tray 22, the crimping region (corresponding to the binding position B) pinched by the upper crimping teeth 32a and the lower crimping teeth 32b in step S1306 overlaps with the liquid application region (corresponding to the liquid application position B) where the tip of the liquid application member 44 contacted in step S1303. In other words, the crimping unit 32 performs crimp binding on the region of the stack of sheets Pb placed on the inner tray 22 where the liquid has been applied by the liquid application unit 31. Incidentally, the crimping region pinched by the upper crimping teeth 32a and the lower crimping teeth 32b does not necessarily completely overlap with the liquid application region where the tip of the liquid application member 44 contacted, and sufficient binding strength can be obtained even when they partially overlap.

[0084] Next, the controller 100 determines whether the number of discharged paper bundles Pb has reached the required number indicated by the binding process instruction (S1308). When the controller 100 determines that the required number has not been reached (S1308: No), it executes the processes after step S1302 again. That is, the controller 100 repeatedly executes the processes of steps S1302 to S1307 until the number of paper bundles Pb discharged to the discharge tray 26 reaches the required number (S1308: No).

[0085] Then, when the controller 100 determines that the number of paper bundles Pb discharged to the discharge tray 26 has reached the required number (S1308: Yes), it drives the end-binding process unit moving motor 50 to move the end-binding process unit 25 to the standby position HP as shown in FIG. 12(A) (S1309). Further, when the posture indicated by the binding process instruction is the "oblique binding posture", the controller 100 drives the liquid application unit rotation motor 563 and the crimping unit rotation motor 56 to rotate the liquid application unit 31 and the crimping unit 32 to the parallel binding posture (S1309). On the other hand, when the posture indicated by the binding process instruction is the "parallel binding posture", the operation of rotating the liquid application unit 31 and the crimping unit 32 to the parallel binding posture is omitted. As a result, the liquid application unit 31 and the crimping unit 32 return to the standby position HP in FIG. 12(A). In steps S1301 and S1309, the execution order of the movement in the main scanning direction and the forward and reverse rotation of the liquid application unit 31 and the crimping unit 32 is not limited to the above order and may be the reverse order.

[0086] FIG. 13 is a diagram showing the binding force when the paper bundle Pb is crimped and bound. As shown in FIG. 13(A), when 10 (N = 10) sheets of paper P are crimped and bound by the upper crimping teeth 32a and the lower crimping teeth 32b, the outer sheets of paper P (for example, the first, second, ninth, and tenth sheets) are relatively greatly deformed, while the deformation amount of the inner (middle) sheets of paper P (for example, the fifth and sixth sheets) is relatively small.

[0087] Accordingly, as shown in FIG. 13(B), the binding force applied to each sheet P (the first to the tenth sheets) increases toward the outside and decreases toward the inside. As a result, the fifth and sixth sheets P with weak crimping strength may peel off, and the crimp-bound sheet bundle Pb may be separated afterwards. This becomes more prominent as the number of sheets P (=N) constituting the sheet bundle Pb increases.

[0088] [Binding Times Determination Process] FIG. 14 is a flowchart of the binding times determination process. The binding times determination process is a process for determining the number of times and the execution timing of crimp binding when crimp-binding a sheet bundle Pb composed of N sheets of paper P. In this embodiment, the number N of sheets P constituting the sheet bundle Pb is set to 10, but the value of N is not limited to this. The controller 100 executes the binding times determination process shown in FIG. 14, for example, prior to executing the binding process shown in FIG. 11 or FIG. 15 when acquiring a binding process instruction.

[0089] First, the controller 100 compares the predetermined number N indicated by the binding process instruction with a predetermined threshold value (S1401). The threshold value is the limit number of sheets that can be properly bound by one-time crimp binding, and is a value appropriately determined according to, for example, the maximum torque of the approach / separation motor 32d (that is, the binding force of the crimping portion 32).

[0090] Then, when the predetermined number N is less than the threshold value (S1401: Yes), the controller 100 determines the number of binding times to be 1 (S1402), and ends the binding times determination process. In this case, in the binding process shown in FIG. 11, the controller 100 causes the crimping portion 32 to perform crimp binding only when N sheets of paper P are placed on the internal tray 22. In other words, the controller 100 does not cause the crimping portion 32 to perform crimp binding until N sheets of paper P are placed on the internal tray 22. The procedure of the binding process in this case is as described with reference to FIG. 11.

[0091] On the other hand, when the predetermined number N is equal to or greater than the threshold value (S1401: No), the controller 100 determines that the number of binding operations is two (S1403). That is, when M (<N) sheets of paper P are placed on the internal tray 22 (the first time) and when N sheets of paper P are placed on the internal tray 22 (the second time), the controller 100 causes the crimping unit 32 to perform crimp binding. In the example of FIG. 14, the case where the crimp binding is performed once and the case where the crimp binding is performed twice are described. However, when the predetermined number N is even larger, the crimp binding may be performed three or more times.

[0092] Next, the controller 100 determines the timing of the first crimp binding (i.e., the value of M). On the other hand, the timing of the second crimp binding is the time when N sheets of paper P are placed on the internal tray 22. The controller 100 determines whether the predetermined number N is even or odd (S1404).

[0093] When the predetermined number N is even (S1404: Yes), the controller 100 determines the value of M within the range of (N × 1 / 2 - 2) or more and less than N (S1405). For example, when the predetermined number N is 10, the value of M is in the range of 3 to 9. More preferably, the controller 100 determines the value of M to be (N × 1 / 2 + 1) (in this case, M = 6). On the other hand, when the predetermined number N is odd (S1404: No), the controller 100 determines the value of M within the range of (N × 1 / 2 - 2.5) or more and less than N (S1406). For example, when the predetermined number N is 11, the value of M is in the range of 3 to 10. More preferably, the controller 100 determines the value of M to be (N × 1 / 2 + 1.5) (in this case, M = 7).

[0094] [Binding process for performing crimp binding twice] FIG. 15 is a flowchart of a binding process that performs pressure binding twice. FIG. 16 is a diagram showing the state of the paper bundle Pb when liquid is applied to the same binding position B. FIG. 17 is a diagram showing the state of the paper bundle Pb when binding the same binding position B twice. When the controller 100 determines the number of bindings to be two in the binding number determination process, it executes the binding process shown in FIG. 15. Hereinafter, with M = 6 and N = 10, the process of FIG. 15 will be described. However, the values of M and N are not limited to this.

[0095] In addition, in FIG. 15, the processes of steps S1501 - S1502 are added to the binding process shown in FIG. 11. Also, for the processes common to FIG. 11, the same step numbers are assigned and the description is omitted. Further, in FIG. 15, the illustration of steps S1308 - S1309 in FIG. 11 is omitted, but this process may be executed.

[0096] First, the controller 100 sequentially executes the processes of steps S1302 - S1303 for the papers P from the first sheet to the sixth sheet. As a result, as shown by the ellipse in FIG. 16(A), liquid is applied to the binding position B of each of the papers P from the first sheet to the sixth sheet by the liquid application unit 31. However, the controller 100 does not need to apply liquid to all the papers P from the first sheet to the sixth sheet. That is, the controller 100 may cause the liquid application unit 31 to apply liquid to the binding position B of at least one of the papers P from the first sheet to the sixth sheet.

[0097] Next, when the sixth sheet of paper P is placed on the inner tray 22 (S1501: Yes), the controller 100 executes the processes of steps S1305 - S1306 for the six sheets of paper P placed on the inner tray 22. That is, the controller 100 causes the pressure bonding unit 32 to perform pressure binding on the binding position B of the six sheets of paper P placed on the inner tray 22 as shown in FIGS. 17(A) - 17(B) (S1306).

[0098] Next, the controller 100 sequentially executes the processes of steps S1302 - S1303 on the 7th to 10th sheets of paper P placed on the inner tray 22 so as to overlap the six sheets of paper P that have been pressure-bound. As a result, as shown by the ellipse in Fig. 16(B), liquid is applied to the binding positions B of each of the 7th to 10th sheets of paper P by the liquid application unit 31. However, the controller 100 does not necessarily need to apply liquid to all the sheets of paper P from the 7th to the 10th. That is, the controller 100 only needs to cause the liquid application unit 31 to apply liquid to the binding position B of at least one sheet of paper P from the 7th to the 10th.

[0099] Next, when the 10th sheet of paper P is placed on the inner tray 22 (S1502: Yes), the controller 100 executes the processes of steps S1305 - S1307 on the 10 sheets of paper P placed on the inner tray 22. That is, as shown in Figs. 17(C) to 17(E), the controller 100 causes the crimping unit 32 to perform pressure binding on the binding position B of the 10 sheets of paper P placed on the inner tray 22 (S1306). Then, the controller 100 discharges the paper bundle Pb whose binding position B has been pressure-bound twice to the discharge tray 26 (S1307).

[0100] As described above, in the examples of Figs. 16 and 17, when the paper P is viewed in the thickness direction, liquid is applied by the liquid application unit 31 (S1303) and pressure binding is performed by the crimping unit 32 (S1306) on the same position on the paper P (i.e., the same binding position B). However, the controller 100 may perform the first pressure binding and the second pressure binding on different binding positions B1 and B2. Hereinafter, with reference to Figs. 18 to 20, an example of performing pressure binding on different binding positions B1 and B2 will be described.

[0101] FIG. 18 is a diagram showing the state of the paper bundle Pb when liquid is applied to different binding positions B1 and B2. FIG. 19 is a diagram showing the state of the paper bundle Pb when binding different binding positions B1 and B2. FIG. 20 is a diagram showing variations of the binding positions B1 and B2. Note that the binding positions B1 and B2 are positions on the paper P that do not overlap each other (i.e., different positions) when viewed from the thickness direction of the paper P. The binding position B1 is an example of a first binding position, and the binding position B2 is an example of a second binding position.

[0102] First, the controller 100 sequentially executes the processes of steps S1302 - S1303 for the binding positions B1 and B2 of the papers P from the first sheet to the sixth sheet. That is, as shown in FIG. 18(A), the controller 100 causes the liquid application unit 31 to apply liquid to the binding position B1 of at least one of the papers P from the first sheet to the sixth sheet (S1303). On the other hand, the controller 100 may or may not cause the liquid application unit 31 to apply liquid to the binding position B2 of at least one of the papers P from the first sheet to the sixth sheet (S1303).

[0103] Next, when the sixth sheet of paper P is placed on the internal tray 22 (S1501: Yes), the controller 100 executes the processes of steps S1305 - S1306 for these six sheets of paper P. That is, as shown in FIGS. 19(A) to 19(B), the controller 100 causes the crimping unit 32 to perform crimping binding on the binding position B1 of the six sheets of paper P placed on the internal tray 22 (S1306).

[0104] Next, the controller 100 sequentially executes the processes of steps S1302 - S1303 for the papers P from the seventh sheet to the tenth sheet placed on the internal tray 22 so as to overlap the six sheets of paper P that have been crimping - bound. That is, as shown in FIG. 18(B), the controller 100 causes the liquid application unit 31 to apply liquid to the binding position B2 of at least one of the papers P from the seventh sheet to the tenth sheet (S1303). On the other hand, no liquid is applied to the binding position B1 of the papers P from the seventh sheet to the tenth sheet.

[0105] Next, when the tenth sheet of paper P is placed on the inner tray 22 (S1502: Yes), the controller 100 executes the processes of steps S1305 - S1306 on the ten sheets of paper P placed on the inner tray 22. That is, as shown in FIGS. 19(C) to 19(E), the controller 100 causes the crimping unit 32 to perform crimp binding on the binding position B2 of the ten sheets of paper P placed on the inner tray 22 (S1306). Then, the controller 100 discharges the paper bundle Pb in which the binding positions B1 and B2 have been crimp - bound once each to the discharge tray 26 (S1307).

[0106] Note that, as shown in FIGS. 20(A) and 20(C), the binding positions B1 and B2 may be positions shifted in the main scanning direction. Also, as shown in FIG. 20(D), the binding positions B1 and B2 may be positions shifted in the conveyance direction. Further, as shown in FIG. 20(C), the binding positions B1 and B2 may be positions shifted in both the main scanning direction and the conveyance direction. However, the positional relationship of the binding positions B1 and B2 is not limited to the example of FIG. 20. Furthermore, as shown in FIG. 20(A), the binding positions B1 and B2 may be parallel binding, or as shown in FIGS. 20(B) to 20(D), they may be diagonal binding. The same applies to the binding position B.

[0107] [Effects of the Embodiment] FIG. 21 is a diagram comparing the binding forces of the binding process of FIG. 11 and the binding process of FIG. 15. As shown in the left diagram of FIG. 21, when ten sheets of paper P are crimp - bound only once, the binding force between the fourth, fifth, and sixth sheets becomes relatively small. On the other hand, as shown in the middle diagram of FIG. 21, when the first to sixth sheets of paper P are subjected to the first crimp binding, although the binding force between the third and fourth sheets becomes relatively small, it is larger than the minimum binding force in the left diagram of FIG. 21. Furthermore, as shown in the right diagram of FIG. 21, when the first to tenth sheets of paper P are subjected to the second crimp binding, although the binding force between the sixth and seventh sheets becomes relatively small, it is larger than the minimum binding force in the left diagram of FIG. 21.

[0108] In this way, by crimp-binding a stack of sheets Pb composed of N sheets of paper P at the time of the M-th (e.g., 6-th) sheet and the N-th (e.g., 10-th) sheet, the crimp strength of the paper P located in the middle is improved. As a result, it is possible to prevent the crimp-bound stack of sheets Pb from being separated afterwards. Note that, out of the two crimp-bindings, the crimping time of the first crimp-binding may be shortened (or the binding force may be weakened) for temporary fixing, and the crimping time of the second crimp-binding may be lengthened (or the binding force may be strengthened) for final binding.

[0109] Also, as shown in FIG. 17, by performing two crimp-bindings on the same binding position B, the moving distance of the edge-binding processing unit 25 can be shortened. Therefore, compared with the example of FIG. 19, the productivity of the post-processing apparatus 3 is improved. Also, since there is only one binding mark, the appearance of the crimp-bound stack of sheets Pb is also improved. On the other hand, as shown in FIG. 19, by performing crimp-binding on different binding positions B1 and B2, the crimp strength can be improved compared with the example of FIG. 17. However, it is desirable that the binding positions B1 and B2 be as close as possible. Further, when the predetermined number N is less than the threshold value, by performing crimp-binding only once, the productivity of the post-processing apparatus 3 is further improved.

[0110] Furthermore, according to the above-described embodiment, by applying a liquid to the binding positions B, B1, and B2, the crimp strength of the paper P located in the middle is improved. As a result, it is possible to more effectively prevent the crimp-bound stack of sheets Pb from being separated afterwards. Note that, in the examples of FIGS. 16 and 18, either or both of the liquid application to the first to sixth sheets of paper P and the liquid application to the seventh to tenth sheets of paper P may be omitted.

[0111] Also, the control method described above may be realized by, for example, a program or the like. That is, the control method is a method in which a computer operates in cooperation with an arithmetic unit, a storage unit, an input unit, an output unit, and a control unit based on a program. Also, the program may be written and distributed in a storage device, a storage medium, or the like, or may be distributed through an electric communication line or the like.

[0112] Note that the present invention is not limited to the embodiments exemplified above, and various modifications are possible without departing from the technical gist thereof. All technical matters included in the technical idea described in the claims are the subject of the present invention. The above embodiments show preferred examples, but those skilled in the art can realize various modified examples from the disclosed content. Such modified examples are also included in the technical scope described in the claims.

[0113] Aspects of the present invention are as follows, for example. <1> A placement unit for placing a medium, Pressure bonding means for performing pressure bonding to press and bind a plurality of the media placed on the placement unit, And control means for controlling the pressure bonding means, The control means causes the pressure bonding means to perform the pressure bonding when M (<N) media are placed on the placement unit and when N media are placed on the placement unit when binding N media. A medium processing apparatus characterized by the above. <2> In the medium processing apparatus according to <1> above, When N is an even number, the control means causes the pressure bonding means to perform the first pressure bonding when M media that are (N×1 / 2 - 2) or more and less than N are placed on the placement unit. A medium processing apparatus characterized by the above. <3> In the medium processing apparatus according to <1> or <2> above, When N is an odd number, the control means causes the pressure bonding means to perform the first pressure bonding when M media that are (N×1 / 2 - 2.5) or more and less than N are placed on the placement unit. A medium processing apparatus characterized by the above. <4> In the medium processing apparatus according to any one of <1> to <3> above, The control means, Performs the pressure bonding on the pressure bonding means with respect to the binding position of the M media placed on the placement unit, A media processing apparatus, characterized in that the crimp binding means is caused to perform the crimp binding on the binding positions of the N sheets of the media placed on the placement unit. <5> In the media processing apparatus according to <4> above, further comprising liquid applying means for applying liquid to the media placed on the placement unit, the control means causes the liquid applying means to apply liquid to the binding positions of at least one of the first to M-th sheets of the media placed on the placement unit, A media processing apparatus, characterized in that the liquid applying means is caused to apply liquid to the binding positions of at least one of the (M + 1)-th to N-th sheets of the media placed on the placement unit. <6> In the media processing apparatus according to any one of <1> to <3> above, the control means causes the crimp binding means to perform the crimp binding on the first binding positions of the M sheets of the media placed on the placement unit, A media processing apparatus, characterized in that the crimp binding means is caused to perform the crimp binding on second binding positions different from the first binding positions of the N sheets of the media placed on the placement unit. <7> In the media processing apparatus according to <6> above, further comprising liquid applying means for applying liquid to the media placed on the placement unit, the control means causes the liquid applying means to apply liquid to the first binding positions of at least one of the first to M-th sheets of the media placed on the placement unit, A media processing apparatus, characterized in that the liquid applying means is caused to apply liquid to the second binding positions of at least one of the first to N-th sheets of the media placed on the placement unit. <8> In the media processing apparatus according to any one of <1> to <7> above, the control means when N is equal to or greater than the threshold value, at the time when the M sheets of the media are placed on the placement unit, causes the crimp binding means to perform the first crimp binding. When N is less than the threshold value, when N sheets of the media are placed on the placement unit, the first crimp binding is performed on the crimp binding means. A media processing apparatus characterized by this. <9> An image forming apparatus that forms an image on the media, An image forming system comprising the media processing apparatus according to any one of <1> to <8> above.

Explanation of Signs

[0114] 1: Image forming system 2: Image forming apparatus 3: Post-processing apparatus (media processing apparatus) 10 - 19: Conveyor roller pair (conveyor section) 20: Switching claw 21, 26, 30: Discharge tray 22: Internal tray 23, 27: End fence 24L, 24R: Side fence 25: Edge binding processing section 28: Middle binding processing section 29: Paper folding blade 31: Liquid application section 32: Crimping section 32a: Upper crimping teeth 32b: Lower crimping teeth 32d: Approach / separation motor 33: Lower pressing plate 34: Upper pressing plate 34a: Through hole 35: Liquid application section moving mechanism 36: Liquid application mechanism 37: Liquid application section moving motor 38: Trapezoidal screw 39: Nut 40: Base plate 40a: Movement sensor 41a, 41b: Columnar members 42a, 42b: Coil springs 43: Liquid storage tank 43a: Liquid level detection sensor 44: Liquid application member 45: Liquid supply member 45a: Protection member 46: Joint 47: End-binding process part moving mechanism 48: Base member 49: Guide shaft 50: End-binding process part moving motor 51: Standby position sensor 90: Approach and separation mechanism 91: Upper arm 92: Lower arm 93: Coil spring 94: Driving gear 95: Driven gear 96: Eccentric cam 97: Rotating shaft 100: Controller 101: CPU 102: RAM 103: ROM 104: HDD 105: I / F 109: Common bus 110: Operation panel 140: HDD

Prior art documents

Patent documents

[0115]

Patent Document 1

Claims

1. A placement part for placing media, Crimping binding means for performing crimping binding to press and deform and bind a plurality of the media placed on the placement part, Control means for controlling the crimping binding means, The control means, when binding N sheets of the media, causes the crimping binding means to perform the crimping binding at the time when M (<N) sheets of the media are placed on the placement part and at the time when N sheets of the media are placed on the placement part. A media processing apparatus characterized by this.

2. In the media processing apparatus according to Claim 1, When N is an even number, the control means causes the crimping binding means to perform the first crimping binding at the time when M sheets of the media, which are (N×1 / 2−2) or more and less than N, are placed on the placement part. A media processing apparatus characterized by this.

3. In the media processing apparatus according to Claim 1, When N is an odd number, the control means causes the crimping binding means to perform the first crimping binding at the time when M sheets of the media, which are (N×1 / 2−2.5) or more and less than N, are placed on the placement part. A media processing apparatus characterized by this.

4. In the media processing apparatus according to Claim 1, The control means, Performs the crimping binding on the crimping binding means with respect to the binding position of M sheets of the media placed on the placement part, A media processing apparatus characterized by performing the crimping binding on the crimping binding means with respect to the binding position of N sheets of the media placed on the placement part.

5. In the media processing apparatus according to Claim 4, Further includes liquid applying means for applying liquid to the media placed on the placement part, The control means, Causes the liquid applying means to apply liquid to at least one of the first to Mth sheets of the media placed on the placement part with respect to the binding position, A media processing apparatus characterized by causing the liquid applying means to apply liquid to at least one of the (M + 1)th to Nth sheets of the media placed on the placement part with respect to the binding position.

6. In the media processing apparatus according to Claim 1, The control means, Performs the crimping binding on the crimping binding means with respect to the first binding position of M sheets of the media placed on the placement part, A media processing apparatus characterized by performing the crimping binding on the crimping binding means with respect to a second binding position different from the first binding position of N sheets of the media placed on the placement part.

7. In the media processing apparatus according to Claim 6, The apparatus further includes liquid applying means for applying liquid to the medium placed on the placing section. The control means causes the liquid applying means to apply liquid to the first binding position of at least one of the first to Mth media placed on the placing section. A medium processing apparatus, characterized in that the liquid applying means is caused to apply liquid to the second binding position of at least one of the first to Nth media placed on the placing section.

8. In the medium processing apparatus according to claim 1, the control means when N is greater than or equal to the threshold value, causes the crimping binding means to perform the first crimping binding when M media are placed on the placing section. A medium processing apparatus, characterized in that when N is less than the threshold value, the crimping binding means is caused to perform the first crimping binding when N media are placed on the placing section.

9. An image forming system including an image forming apparatus for forming an image on the medium, and the medium processing apparatus according to claim 1.

Images