Medium processing apparatus and image forming system

Abstract

A medium processing apparatus includes a crimper and a controller. The crimper presses and deforms a medium bundle including a plurality of media, with a pair of binding teeth, to bind the medium bundle. The controller controls an operation of the crimper. The controller switches whether to execute a pressing-hold control of holding a state in which the medium bundle is pressed and deformed with the pair of binding teeth.

Description

[DESCRIPTION][Title of Invention]MEDIUM PROCESSING APPARATUS AND IMAGE FORMING SYSTEM[Technical Field]

[0001] The present disclosure relates to a medium processing apparatus and an image forming system.[Background Art]

[0002] Medium processing apparatuses have been proposed that bind sheet-shaped media, on which images are formed by an image forming apparatus, into a bundle of media. Since sheets of paper are widely known as an example of sheet-shaped media, a “sheet bundle” that is a stack of sheets of paper is used as an example of a bundle of sheet-shaped media in the following description. From the viewpoint of saving resources and reducing environmental load, some medium processing apparatuses include a crimping device that can perform so-called "crimping" to pinch a sheet bundle by serrated binding teeth and press and deform the sheet bundle without using metal staples.

[0003] An increased number of sheets of the sheet bundle hamper the binding teeth in biting into the sheet bundle and may cause some sheets to peel off from the bound sheets. Thus, crimping has some difficulties in keeping the sheet bundle bound as appropriate. For this reason, some medium processing apparatuses hold a state in which a bundle of sheets is pressed by binding teeth for a predetermined time, which may be referred to as “pressing-hold control," to reliably crimp the bundle of sheets (e.g., see Patent Literature (PTL) 1).[Citation List][Patent literature]

[0004] [PTL 1] Japanese Unexamined Patent Application Publication No. 2014-226799 [Summary of Invention] [Problems to be Solved]

[0005] However, as in PTL 1, when the pressing-hold control is always executed regardless of the state of the bundle of sheets (e.g., the number of sheets, the sheet thickness, and the type of sheet), the pressing force is too strong depending on the state of the bundle of sheets, which may damage the bundle of sheets or a pressing unit.

[0006] The present disclosure has been made to solve such a problem, and an object of the present disclosure is to provide a medium processing apparatus that can crimp and bind a bundle of media with an appropriate binding strength.[Solution to Problem]

[0007] In order to solve the above-described problem, the present disclosure described herein provides a medium processing apparatus that includes a crimper and a controller. The crimper presses and deforms a medium bundle including a plurality of media, with a pair of binding teeth, to bind the medium bundle. The controller controls an operation of the crimper. The controller switches whether to execute a pressing-hold control of holding a state in which the medium bundle is pressed and deformed with the pair of binding teeth. [Advantageous Effects of Invention]

[0008] According to an aspect of the present disclosure, a medium processing apparatus that can crimp and bind a medium bundle with an appropriate binding strength can be obtained. [Brief Description of Drawings]

[0009] A more complete appreciation of embodiments of the present disclosure and many of the attendant advantages and features thereof can be readily obtained and understood from the following detailed description with reference to the accompanying drawings.

[0010] [FIG. 1]FIG. 1 is a diagram illustrating an overall configuration of an image forming system.[FIG. 2]FIG. 2 is a diagram illustrating an internal structure of a post-processing apparatus according to a first embodiment.[FIG. 3]FIG. 3 is a schematic view of an edge binder viewed from an upstream side in a conveyance direction.[FIG. 4]FIG. 4 is a schematic view of an edge binder viewed from the side on which a liquid applier is located in a main scanning direction.[FIG. 5]FIGS. 5 A and 5B are schematic diagrams illustrating a configuration of a crimper of an edge binder.[FIG. 6]FIG. 6 is a diagram illustrating an edge binder according to a modification.[FIG. 7]FIGS. 7A, 7B, and 7C are diagrams illustrating a liquid application crimper of an edge binder according to a modification.[FIG. 8]FIGS. 8 A, 8B, and 8C are diagrams illustrating a liquid applying operation and a crimping operation performed by the liquid application crimper of FIGS. 7A, 7B, and 7C.[FIG. 9]FIG. 9 is a schematic view of a staple binder viewed from an upstream side in a conveyance direction.[FIG. 10]FIG. 10 is a schematic view of a staple binder according to a modification, viewed from an upstream side in a conveyance direction.[FIG. 11]FIG. 11 is a block diagram illustrating the hardware configuration of controlling operations of the post-processing apparatus according to the first embodiment.[FIG. 12]FIGS. 12A, 12B, 12C, and 12D are diagrams illustrating a contact-separation assembly to move an upper crimping teeth and a lower crimping teeth close to and away from each other. [FIG. 13]FIG. 13 is a diagram illustrating a hardware configuration of a post-processing apparatus according to a second embodiment.[FIG. 14]FIG. 14A is an example of a pressing-hold setting screen and FIGS. 14B and 14C are examples of data of a pressing-hold control table.[FIG. 15]FIG. 15 is a flowchart of a binding process.[FIG. 16]FIGS. 16A, 16B, and 16C are diagrams illustrating the positions of a liquid applier and a crimper during a binding process.[FIG. 17]FIG. 17 is a flowchart of a crimping process.[FIG. 18]FIG. 18 is a graph illustrating a relation between a processing time of a crimping process and a pressing force applied to a sheet bundle.[FIG. 19]FIG. 19 is a diagram illustrating an internal structure of a post-processing apparatus according to a third embodiment.[FIG. 20]FIGS. 20A, 20B, and 20C are schematic views of an internal tray according to a third embodiment, viewed from a thickness direction of a sheet.[FIG. 21]FIG. 21 is a schematic view of a crimper according to a third embodiment, viewed from an upstream side in a conveyance direction.[FIG. 22]FIGS. 22A and 22B are schematic views of a liquid applier according to the third embodiment, viewed from the thickness direction of the sheet.[FIG. 23]FIGS. 23A, 23B, and 23C are cross-sectional views of the liquid applier, taken along a lineXXV-XXV of FIG. 22A.[FIG. 24]FIGS. 24A, 24B, and 24C are cross-sectional views of the liquid applier taken along a lineXXVI-XXVI of FIG. 22A.[FIG. 25]FIG. 25 is a diagram illustrating a hardware configuration of control blocks of the postprocessing apparatus according to the third embodiment to control an operation of the postprocessing apparatus.[FIG. 26]FIG. 26 is a flowchart of post-processing performed by the post-processing apparatus according to the third embodiment.[FIG. 27]FIG. 27 is a diagram illustrating an overall configuration of an image forming system according to a modification.[FIG. 28]FIGS. 28 A and 28B are schematic views of a post-processing apparatus including controllers according to a first modification.[FIG. 29]FIGS. 29A and 29B are schematic views of a post-processing apparatus including controllers according to a second modification.

[0011] The accompanying drawings are intended to depict embodiments of the present disclosure and should not be interpreted to limit the scope thereof. The accompanying drawings are not to be considered as drawn to scale unless explicitly noted. Also, identical or similar reference numerals designate identical or similar components throughout the several views. [Description of Embodiments]

[0012] In describing embodiments illustrated in the drawings, specific terminology is employed for the sake of clarity. However, the disclosure of this specification is not intended to be limited to the specific terminology so selected and it is to be understood that each specific elementincludes all technical equivalents that have a similar function, operate in a similar manner, and achieve a similar result.

[0013] Referring now to the drawings, embodiments of the present disclosure are described below. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0014] Embodiments of the present disclosure are described below with reference to the accompanying drawings. Note that identical parts are given identical reference signs and redundant descriptions are summarized or omitted accordingly.

[0015] A description is given below of an image forming system 1 with reference to the drawings. FIG. 1 is a diagram illustrating an overall configuration of the image forming system 1. The image forming system 1 has, for example, an image forming function of forming an image on a sheet P as an example of a sheet-shaped medium and a post-processing function of performing post-processing on the sheet P on which the image has been formed. As illustrated in FIG. 1, the image forming system 1 includes an image forming apparatus 2 having the image forming function and a post-processing apparatus 3 serving as a medium processing apparatus having the post-processing function. In the image forming system 1, the image forming apparatus 2 and the post-processing apparatus 3 operate in conjunction with each other.

[0016] In the present embodiment, the sheet-shaped medium or sheet-shaped medium to be processed in the image forming system 1 is described on the assumption that the medium is a sheet of “paper”. However, the object to be processed according to the present embodiment is not limited to a sheet of paper. For example, any type of medium can be used as long as an image can be formed on the medium according to an image forming process. Examples of the medium include a medium that can be an object of a folding process or a binding process, and the material and specification of the medium are not limited to any particular material and specification.

[0017] The image forming apparatus 2 forms an image on the sheet P and ejects the sheet P having the image to the post-processing apparatus 3. The image forming apparatus 2 includes an accommodation tray 211 that accommodates sheets P, a conveyor 212 that conveys a sheet P from the accommodation tray 211, and an image forming device 213 that forms an image on the sheet P conveyed by the conveyor 212. The image forming device 213 may be an inkjet system that forms an image using ink or an electrophotographic system that forms an image using toner. The image forming apparatus 2 also includes a controller 100a that controls various operations of the conveyor 212 and the image forming device 213. Since the imageforming apparatus 2 of FIG. 1 has a known configuration, a detailed description of the configuration and functions of the image forming apparatus 2 is omitted.

[0018] Sheets of paper are widely known as an example of sheet- shaped media. In the following description, a sheet-shaped medium as a medium to be processed is referred to as a “sheet P.” Further, in the following description, a bundle of sheets of paper as a plurality of media is an example of a “sheet bundle Pb.”

[0019] A description is given of the post-processing apparatus 3 according to a first embodiment. FIG. 2 is a diagram illustrating an internal structure of the post-processing apparatus 3 according to the first embodiment. The post-processing apparatus 3 has a function that performs post-processing on the sheet P on which an image has been formed by the image forming apparatus 2. An example of the post-processing according to the present embodiment is a binding process as a “crimping process” that binds, without staples, a plurality of sheets P on each of which an image is formed as a bundle of sheets, which may be referred to as a sheet bundle. Another example of the post-processing according to the present embodiment is a binding process as a “stapling process” that binds, with staples, a plurality of the sheets P on each of which an image is formed as a bundle of sheets P (i.e., sheet bundle). In the following description, the bundle of sheets P may be referred to as a “sheet bundle Pb” as a bundle of media.

[0020] In the present embodiment, a description is given of liquid application in a crimping process. However, liquid application performed in a stapling process is similar to the liquid application in the crimping process. In the following description, the term "binding process" indicates both the “crimping process" and the "stapling process", and is not limited to a binding method (whether a binding needle is used or a pressing and deforming process is performed).

[0021] More specifically, the “crimping process” according to the present embodiment is a process called “crimping” or “crimp binding“ to apply pressure to the binding position corresponding to a part of the sheet bundle Pb to deform (pressure-deform) the binding position and bind the sheet bundle Pb. The binding that can be executed by the post-processing apparatus 3 includes edge binding and saddle binding. The edge binding is a process to bind an end (including an edge) of the sheet bundle Pb. The saddle binding is a process to bind the center of the sheet bundle Pb.

[0022] The post-processing apparatus 3 includes conveyance roller pairs 10 to 19 (an example of conveyors), a switcher 20, and a controller 100b (an example of a control device). The controller 100b controls the operations of, for example, the conveyance roller pairs 10 to 19 (an example of conveyors), and the switcher 20. Details of the controller 100b will bedescribed below. The conveyance roller pairs 10 to 19 convey, inside the post-processing apparatus 3, a sheet P supplied from the image forming apparatus 2. Specifically, the conveyance roller pairs 10 to 13 convey the sheet P along a first conveyance passage Phi.The conveyance roller pairs 14 and 15 convey the sheet P along a second conveyance passage Ph2. The conveyance roller pairs 16 to 19 convey the sheet P along a third conveyance passage Ph3. A hole punch 132 is disposed between the conveyance roller pairs 10 and 11. The hole punch 132 performs punching on the sheet P conveyed by the conveyance roller pairs 10 and 11.

[0023] The first conveyance passage Phi is a passage extending to an ejection tray 21 from a supply port through which the sheet P is supplied from the image forming apparatus 2. The second conveyance passage Ph2 is a passage branching from the first conveyance passage Phi between the conveyance roller pairs 11 and 14 in a conveyance direction and extending to an ejection tray 26 via an internal tray 22. The third conveyance passage Ph3 is a passage branching from the first conveyance passage Phi between the conveyance roller pairs 11 and 14 in the conveyance direction and extending to an ejection tray 30.

[0024] The switcher 20, which is an example of a switcher, is disposed at a branching position of the first conveyance passage Phi and the second conveyance passage Ph2. The switcher 20 can be switched between a first position and a second position. The switcher 20 in the first position guides the sheet P to be ejected to the ejection tray 21 through the first conveyance passage Phi. The switcher 20 in the second position guides the sheet P conveyed through the first conveyance passage Phi to the second conveyance passage Ph2. When a trailing end of the sheet P entering the second conveyance passage Ph2 passes through the conveyance roller pair 11, the conveyance roller pair 14 is rotated in reverse to guide the sheet P to the third conveyance passage Ph3. The post-processing apparatus 3 further includes a plurality of sensors that detects the positions of the sheet P in the first conveyance passage Phi, the second conveyance passage Ph2, and the third conveyance passage Ph3. Each of the multiple sensors is indicated by a black triangle in FIG. 2.

[0025] The post-processing apparatus 3 further includes the ejection tray 21. The sheet P that is ejected through the first conveyance passage Phi rests on the ejection tray 21. Among the sheets P supplied from the image forming apparatus 2, a sheet P not subjected to the binding process is ejected to the ejection tray 21.

[0026] The post-processing apparatus 3 further includes the internal tray 22 serving as a placement tray, an end fence 23, side fences 24L and 24R, an edge binder 25, a staple binder 55, and an ejection tray 26. The internal tray 22, the end fence 23, the side fences 24L and 24R, the edge binder 25, and the staple binder 55 perform edge binding on the sheet bundle Pb including themultiple sheets P conveyed from the second conveyance path Ph2 to the internal tray 22. Among the sheets P supplied from the image forming apparatus 2, the sheet bundle Pb subjected to the edge binding is ejected to the ejection tray 26.

[0027] Examples of the “edge binding process” include, but not limited to, “parallel binding process,” “oblique binding process,” and “vertical binding process.” The “parallel binding process” is a process of binding a sheet bundle Pb along one side of the sheet bundle Pb parallel to the main scanning direction. The “oblique binding process” is a process of binding a corner of a sheet bundle Pb. The “vertical binding process” is a process of binding a sheet bundle Pb at multiple positions, which is away from each other in a width direction of the sheet bundle Pb, along one side of the sheet bundle Pb parallel to a conveyance direction.

[0028] In the following description, a direction in which the sheet P is conveyed from the conveyance roller pair 15 toward the end fence 23 is defined as a “conveyance direction.” In other words, the “conveyance direction” herein corresponds to a direction in which the sheet P that has been output from the image forming apparatus 2 is moved toward the ejection tray 26 by, for example, the conveyance roller pair 10, is changed to move toward the end fence 23 by the conveyance roller pair 15 in a direction different from the above-described direction. The direction that is orthogonal to both the conveyance direction and a thickness direction of the sheet P is defined as a “main scanning direction” or a “width direction of the sheet P.”

[0029] The sheets P that are sequentially conveyed through the second conveyance passage Ph2 are temporarily placed on the internal tray 22 serving as a placement tray. The end fence 23 aligns the position, in the conveyance direction, of the sheet P or the sheet bundle Pb placed on the internal tray 22. The side fences 24L and 24R align the position, in the main scanning direction, of the sheet P or the sheet bundle Pb placed on the internal tray 22. The edge binder 25 and the staple binder 55 bind an end of the sheet bundle Pb aligned by the end fence 23 and the side fences 24L and 24R. The conveyance roller pair 15 ejects the sheet bundle Pb subjected to the edge binding to the ejection tray 26.

[0030] The post-processing apparatus 3 further includes an end fence 27, a saddle binder 28, a sheet folding blade 29, and the ejection tray 30. The end fence 27, the saddle binder 28, and the sheet folding blade 29 perform saddle binding on a sheet bundle Pb foamed of the sheets P that are conveyed through the third conveyance passage Ph3. Among the sheets P supplied from the image forming apparatus 2, the sheet bundle Pb subjected to the saddle binding is ejected to the ejection tray 30.

[0031] The end fence 27 aligns the positions of the sheets P that are sequentially conveyed through the third conveyance passage Ph3, in a conveyance direction in which the sheets P are conveyed. The end fence 27 can move between a binding position where the end fence 27 causes the center of the sheet bundle Pb to face the saddle binder 28 and a folding position where the end fence 27 causes the center of the sheet bundle Pb to face the sheet folding blade 29. The saddle binder 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, in half, the sheet bundle Pb placed on the end fence 27 at the folding position and causes the conveyance roller pair 18 to nip the sheet bundle Pb. The conveyance roller pairs 18 and 19 eject the sheet bundle Pb subjected to the saddle binding to the ejection tray 30.

[0032] A detailed description is given below of the edge binder 25.FIG. 3 is a schematic diagram illustrating an upstream side of the edge binder 25 in the conveyance direction. The edge binder 25 performs liquid application and crimping illustrated in FIG. 2. FIG. 4 is a schematic view of a liquid applier 31 of the edge binder 25 in the main scanning direction. As illustrated in FIGS. 3 and 4, the edge binder 25 includes a liquid applier 31 that applies liquid to the sheets P, and a crimper 32 that is an example of a post-processing device and performs crimping binding on the sheet bundle Pb. The liquid applier 31 and the crimper 32 are disposed adjacent to each other in the main scanning direction downstream from the internal tray 22 in the conveyance direction.

[0033] As illustrated in FIG. 4, the liquid applier 31 as an example of a liquid applier applies the liquid stored in the first liquid storage tank 43 as an example of a liquid storage unit to a sheet P or a sheet bundle Pb placed on the internal tray 22. In the following description, applying liquid to a sheet P or a sheet bundle Pb by the liquid applier 31 and the operation of the liquid applier 31 when applying liquid are referred to as "liquid application." The liquid application operation of the liquid applier 31 accompanied by the control process is referred to as a "liquid application process."

[0034] More specifically, the liquid that is stored in the first liquid storage tank 43 as liquid for the “liquid application” includes, as a main component, the liquid state of a compound of hydrogen and oxygen compound represented by the chemical formula H2O. The liquid hydrogen-oxygen compound is at any temperature. For example, the liquid hydrogen-oxygen compound may be so-called warm water or hot water. The liquid hydrogen-oxygen compound is not limited to pure water. The liquid hydrogen-oxygen compound may be purified water or may contain ionized salts. The metal ion content ranges from so-called soft water to ultrahard water. In other words, the liquid hydrogen-oxygen compound is at any hardness.

[0035] The liquid that is stored in the first liquid storage tank 43 may include an additive in addition to the main component. The liquid that is stored in the first liquid storage tank 43 may include residual chlorine used as tap water. Preferably, for example, the liquid that is stored in the first liquid storage tank 43 may include, as an additive, a colorant, a penetrant, a pH adjuster, a preservative such as phenoxyethanol, a drying inhibitor such as glycerin, or a combination thereof. Furthermore, because water is used as a component of ink used for inkjet printers or ink used for water-based pens, such water or ink may be used for the “liquid application”.

[0036] The water is not limited to the specific examples described above. The water may be water in a broad sense such as hypochlorous acid water or an ethanol aqueous solution diluted for disinfection. However, tap water may be used simply to enhance the binding strength after the binding process because tap water is easy to obtain and store. A liquid including water as a main component as exemplified above enhances the binding strength of the sheet bundle Pb, in comparison with a liquid of which the main component is not water (liquid).

[0037] As illustrated in FIGS. 3 and 4, the liquid applier 31 can be moved in the main scanning direction together with the crimper 32 by the driving force transmitted from the edge-binder movement motor 50. The liquid applier 31 includes a lower pressure plate 33 as an example of a placement table for a sheet P or a sheet bundle Pb, an upper pressure plate 34, a liquid- applier movement assembly 35, and a liquid application assembly 36. The components of the liquid applier 31 (the lower pressure plate 33, the upper pressure plate 34, the liquid- applier movement assembly 35, the liquid application assembly 36, and the liquid- applier movement motor 37) are held by the liquid application frame 31a and the base 48.

[0038] As illustrated in FIG. 3, the liquid applier 31 includes a liquid- applier pivot assembly 252. The liquid- applier pivot assembly 252 includes a liquid-applier pivot motor 563, an output gear 563a, and a drive transmission gear 562a, which will be described later. A liquid-applier rotation shaft 562 provided with a drive transmission gear 562a is fixed to a bottom face of the liquid application frame 31a that holds the components of the liquid applier 31. The liquid-applier rotation shaft 562 and the drive transmission gear 562a are held by the base 48 on which the liquid application frame 31a is disposed, so as to be rotatable in the forward and reverse directions.

[0039] The drive transmission gear 562a meshes with an output gear 563a of the liquid-applier pivot motor 563. The liquid applier 31 can be rotated in the forward and reverse directions about the liquid-applier rotation shaft 562 on the base 48 by a driving force transmitted from the liquid-applier pivot motor 563 to the liquid-applier rotation shaft 562 via the output gear 563a and the drive transmission gear 562a.

[0040] The lower pressure plate 33 and the upper pressure plate 34 are disposed downstream from the internal tray 22 in the conveyance direction. The sheet P or the sheet bundle Pb that is placed on the internal tray 22 is also placed on the lower pressure plate 33. The lower pressure plate 33 is disposed on a lower pressure plate holder 331. The upper pressure plate 34 is movable in the thickness direction of the sheet P or the sheet bundle Pb at a position where the upper pressure plate 34 faces the sheet P or the sheet bundle Pb placed on the internal tray 22.

[0041] In other words, the lower pressure plate 33 and the upper pressure plate 34 are disposed to face each other in the thickness direction of the sheet P or the sheet bundle Pb with the sheet P or the sheet bundle Pb placed on the internal tray 22 and interposed between the lower pressure plate 33 and the upper pressure plate 34. In the following description, the thickness direction of the sheet P or the sheet bundle Pb may be referred to simply as “thickness direction.” Further, the upper pressure plate 34 is provided with a through hole 34a passing through the upper pressure plate 34 in the thickness direction at a position opposite to the liquid application member 44 held via the joint 46 attached to the base plate 40. The liquid application member 44 is one end portion of a liquid supply member 45, which is an example of a liquid absorber, described below and corresponds to a tip portion of the liquid supply member 45.

[0042] The liquid- applier movement assembly 35 moves the upper pressure plate 34, the base plate 40, a joint 46, and the liquid application member 44 in the thickness direction of the sheet P or the sheet bundle Pb. The liquid- applier movement assembly 35 according to the present embodiment moves the upper pressure plate 34, the base plate 40, the joint 46, and the liquid application member 44 in conjunction with each other with a single liquid-applier movement motor 37. The liquid-applier movement assembly 35 includes, for example, the liquid-applier movement motor 37, a trapezoidal screw 38, a nut 39, the base plate 40, columns 41a and 41b, and coil springs 42a and 42b.

[0043] The liquid-applier movement motor 37 generates a driving force to move the upper pressure plate 34, the base plate 40, the joint 46, and the liquid application member 44. The trapezoidal screw 38 extends in the thickness direction of the sheet P or the sheet bundle Pb and is provided with the liquid application frame 31a such that the trapezoidal screw 38 is rotatable in the forward and reverse directions. The trapezoidal screw 38 is coupled to an output shaft of the liquid-applier movement motor 37 via, for example, a pulley and a belt. The nut 39 is screwed to the trapezoidal screw 38. The trapezoidal screw 38 is rotated in the forward and reverse directions by the driving force transmitted from the liquid-appliermovement motor 37. The rotation of the trapezoidal screw 38 causes the nut 39 to reciprocate on the trapezoidal screw 38.

[0044] The base plate 40 is positioned apart from the upper pressure plate 34. The base plate 40 holds the liquid application member 44 with the tip portion of the liquid application member 44 protruding from the base plate 40 toward the upper pressure plate 34. The base plate 40 is coupled to the trapezoidal screw 38 via the nut 39 such that base plate 40 can reciprocate along the trapezoidal screw 38 as the trapezoidal screw 38 rotates in the forward and reverse directions. The position of the base plate 40 in the vertical direction is detected by a movement sensor 40a (see FIG. 4).

[0045] The columns 41a and 41b project from the base plate 40 toward the upper pressure plate 34 around the tip portion of the liquid application member 44. The columns 41a and 41b can relatively move with respect to the base plate 40 in the thickness direction. The columns 41a and 41b hold the upper pressure plate 34 with the respective ends closer to the lower pressure plate 33 than the other ends of the columns 41a and 41b. The other ends of the columns 41a and 41b opposite the ends closer to the lower pressure plate 33 are provided with stoppers that prevent the columns 41a and 41b from being removed from the base plate 40.

[0046] The coil springs 42a and 42b are fitted around the columns 41a and 41b, respectively, between the base plate 40 and the upper pressure plate 34. The coil springs 42a and 42b bias the upper pressure plate 34 and the columns 41a and 41b toward the lower pressure plate 33 with respect to the base plate 40.

[0047] The liquid application assembly 36 applies liquid to the sheet P or the sheet bundle Pb placed on the internal tray 22. Specifically, the liquid application assembly 36 brings the liquid application member 44 into contact with the sheet P or the sheet bundle Pb to apply the liquid to at least one sheet P of the sheet bundle Pb. The liquid application assembly 36 includes the liquid application member 44, the liquid supply member 45, the first liquid storage tank 43, and the joint 46.

[0048] The first liquid storage tank 43 stores the liquid to be supplied to the sheet P or the sheet bundle Pb. The liquid stored in the first liquid storage tank 43 is detected by a liquid-level sensor 43 a that is an example of a liquid detector.

[0049] The liquid application member 44 applies the liquid stored in the first liquid storage tank 43 to the sheet P or the sheet bundle Pb. The liquid application member 44 is held by the base plate 40 with the tip portion of the liquid application member 44 facing the upper pressure plate 34.

[0050] Further, the liquid application member 44 includes a material having a relatively high liquid absorption. For example, the liquid application member 44 includes an open cell foam that can contain liquid. The liquid application member 44 is not limited to a particular kind as long as the liquid application member 44 is made of a material having a property of absorbing and holding the liquid and has a property of being crushable in accordance with a pressing force applied when the liquid application member 44 is in contact with the sheet P. The pressing force corresponds to an amount of movement of the liquid application member 44 to the sheet P (or the sheet bundle Pb). For example, the liquid application member 44 may be a foam material such as a sponge or a fiber material that can absorb liquid by capillary action.

[0051] The liquid supply member 45 (liquid absorber) is an elongated member having an immersion portion 452 at a base end (proximal end) immersed in the liquid stored in the first liquid storage tank 43 and a tip end (distal end) coupled to the liquid application member 44. Like the liquid application member 44, for example, the liquid supply member 45 is made of a material having a relatively high liquid absorption. As a result, the liquid absorbed from the immersion portion 452 of the liquid supply member 45 is supplied to the liquid application member 44 by the capillary action. In other words, the liquid stored in the first liquid storage tank 43 is sucked up from the immersion portion 452 of the liquid supply member 45, and the sucked liquid is supplied to the liquid application member 44 that is coupled to the tip portion via the liquid supply member 45.

[0052] As described above, the liquid sucked up from the immersion portion 452 of the liquid supply member 45 is supplied to the liquid application member 44 through the liquid supply member 45, and the liquid application member 44 contacts the upper face of an uppermost sheet of the sheets P or the sheet bundle Pb to apply the liquid.

[0053] Although the case where the liquid supply member 45 and the liquid application member 44 are separate bodies has been described above, the liquid supply member 45 and the liquid application member 44 may be integrally formed of a material having the same properties (e.g., a material having a high liquid absorption rate). In other words, the liquid application member 44 may be part of the liquid supply member 45. In such a case, liquid can be supplied from the liquid supply member 45 to the liquid application member 44 more smoothly by the capillary action.

[0054] A protector 45a is an elongated cylindrical body (e.g., a tube) that is fitted around the liquid supply member 45. Such a configuration prevents the liquid absorbed by the liquid supply member 45 from leaking or evaporating. Each of the liquid supply member 45 and the protector 45a is made of a flexible material. The joint 46 holds the liquid application member 44 and is provided with the base plate 40. Accordingly, even when the liquid applicationmember 44 is moved by liquid-applier movement assembly 35 in a direction orthogonal to the conveyance direction and the main scanning direction, the liquid application member 44 keeps projecting from the base plate 40 toward the upper pressure plate 34 with the tip portion of the liquid application member 44 facing the upper pressure plate 34.

[0055] In the liquid application process, the controller 100b controls the amount of movement (pressing amount) of the liquid application member 44 to the sheet P or the sheet bundle Pb by controlling the amount of driving force of the liquid-applier movement motor 37. By controlling the amount of movement of the liquid application member 44 relative to the sheet P or the sheet bundle Pb, the size of the area (contact area) where the liquid application member 44 contacts the sheet P or the sheet bundle Pb or the contact time of the liquid application member 44 can be adjusted. With such adjustment, the amount of liquid applied to the sheet P or the sheet bundle Pb and the spread of the liquid in the liquid application process can be adjusted.

[0056] A description is given below of a configuration of the crimper 32.The crimper 32 as an example of a post-processing device presses and deforms a portion of the sheet bundle Pb by serrated upper crimping teeth 32a and lower crimping teeth 32b, and crimps the sheets P of the portion to bind the sheet bundle Pb. In short, the crimper 32 binds the sheet bundle Pb without staples. The components of the crimper 32 such as the upper crimping teeth 32a and the lower crimping teeth 32b are disposed on a crimper frame 32c. In the following description, such a way of pressing and deforming a given position on the sheet bundle Pb to bind the sheet bundle Pb may be referred to as “crimping.” In other words, the crimper 32 crimps and binds the sheet bundle Pb or performs the crimping on the sheet bundle Pb. The crimping and binding operation of the crimper 32 that involves control processing is referred to as "crimping process".

[0057] FIGS. 5A and 5B are schematic diagrams illustrating a configuration of the crimper 32. As illustrated in FIGS. 5 A and 5B, the crimper 32 includes the upper crimping teeth 32a and the lower crimping teeth 32b, which may be collectively referred to as binding teeth 32a and 32b in the following description. The upper crimping teeth 32a and the lower crimping teeth 32b are disposed to face each other in the thickness direction of the sheet bundle Pb to sandwich the sheet bundle Pb placed on the internal tray 22. The upper crimping teeth 32a and the lower crimping teeth 32b have respective serrate faces facing each other. The serrate face of each of the upper crimping teeth 32a and the lower crimping teeth 32b includes concave portions and convex portions alternately formed. The concave portions and the convex portions of the upper crimping teeth 32a are shifted from those of the lower crimping teeth 32b such that the upper crimping teeth 32a are engaged with the lower crimping teeth 32b. The upper crimping teeth 32a and the lower crimping teeth 32b are brought into contact withand separated from each other by the driving force of a contact- separation motor 32d illustrated in FIG. 11.

[0058] In the process of supplying the sheets P of the sheet bundle Pb to the internal tray 22, the upper crimping teeth 32a and the lower crimping teeth 32b are separated from each other as illustrated in FIG. 5A. When all the sheets P of the sheet bundle Pb are placed on the internal tray 22, the upper crimping teeth 32a and the lower crimping teeth 32b are engaged with each other as illustrated in FIG. 5B by the driving force of the contact-separation motor 32d to press and deform the sheet bundle Pb in the thickness direction. As a result, the sheet bundle Pb that has been placed on the internal tray 22 is crimped and bound. The sheet bundle Pb thus crimped and bound is ejected to the ejection tray 26 by the conveyance roller pair 15.

[0059] The configuration of the crimper 32 as a crimping assembly is not limited to the configuration of an operating assembly exemplified in the present embodiment, and may be any other suitable structure in which the upper crimping teeth 32a and the lower crimping teeth 32b of the crimping assembly engage with each other. For example, the crimping assembly may be a link- mechanism- type crimping assembly that performs crimping and separating operations of the upper crimping teeth 32a and the lower crimping teeth 32b with a link mechanism and a driving source that simply rotates in the forward direction or that rotates in the forward and backward directions (e.g., the crimping assembly disclosed in Japanese Patent No. 6057167). Alternatively, the crimping assembly may be a linear-mo tion-type crimping assembly that linearly performs crimping and separating operations of the upper crimping teeth 32a and the lower crimping teeth 32b with a screw assembly that converts the forward and backward rotational motions of a driving source into linear reciprocating motion.

[0060] As illustrated in FIG. 3, the crimper 32 includes a crimping -teeth slide assembly 322. The crimping-teeth slide assembly 322 includes a crimping -teeth slide motor 32e, a pinion gear 32el, a rack 32f 1 , and a crimping-teeth frame 32f, which will be described later. The upper crimping teeth 32a and the lower crimping teeth 32b are disposed on the crimping-teeth frame 32f. The crimping-teeth frame 32f is integrally provided with the rack 32f 1 that meshes with the pinion gear 32el, which is described later. The crimping-teeth frame 32f is attached to the crimper frame 32c so that crimping-teeth frame 32f be movable in the main scanning direction. The crimping-teeth slide motor 32e generates a driving force for moving the crimping-teeth frame 32f in the main scanning direction. The pinion gear 32el is mounted on an output shaft of the crimping-teeth slide motor 32e. As the crimping-teeth slide motor 32e is driven to rotate forward and backward, the pinion gear 32el is rotated forward and backward, respectively. As the pinion gear 32el rotates forward and backward, the rack 32f 1 meshing with the pinion gear 32el reciprocates along the main scanning direction with respect to the crimper frame 32c. As a result, the crimping -teeth frame 32f integrallyprovided with the rack 32f 1 also reciprocates along the main scanning direction with respect to the crimper frame 32c. In other words, the upper crimping teeth 32a and the lower crimping teeth 32b provided with the crimping-teeth frame 32f can move in the main scanning direction by the crimping-teeth slide motor 32e being driven to rotate forward and backward. Accordingly, the upper crimping teeth 32a and the lower crimping teeth 32b can execute a binding operation a plurality of times while shifting the positions in the main scanning direction with respect to the sheet bundle Pb.

[0061] The movement amount of the upper crimping teeth 32a and the lower crimping teeth 32b of the crimping assembly in the main scanning direction is set to be equal to or substantially equal to the length of a crimp mark formed by the binding operation of the upper crimping teeth 32a and the lower crimping teeth 32b, and the crimping operation is performed a plurality of times before and after the movement in the main scanning direction. In other words, when the length of the crimp mark formed by the binding operation of the upper crimping teeth 32a and the lower crimping teeth 32b is 10 mm, setting the movement amount in the main scanning direction to 10 mm allows the length of the crimp mark to be 20 mm by combining a crimping operation (first time) before the movement in the main scanning direction and a crimping operation (second time) after the movement in the main scanning direction. Thus, the binding force of the crimper 32 is increased about twice.

[0062] As illustrated in FIG. 3, the crimper 32 includes a crimper pivot assembly 323 (postprocessing device pivot assembly). The crimper pivot assembly 323 includes a crimper pivot motor 56, an output gear 56a, and a drive transmission gear 54a, which will be described later. A crimper rotation shaft 54 having a drive transmission gear 54a is fixed to the bottom face of the crimper frame 32c that holds the components of the crimper 32.

[0063] The crimper rotation shaft 54 and the drive transmission gear 54a are held by a base 48 on which the crimper frame 32c is disposed, so as to be rotatable in the forward and reverse directions. The drive transmission gear 54a meshes with the output gear 56a of the crimper pivot motor 56. The crimper 32 can be rotated in the forward and reverse directions about the crimper rotation shaft 54 on the base 48 by a driving force transmitted from the crimper pivot motor 56 to the crimper rotation shaft 54 via the output gear 56a and the drive transmission gear 54a.

[0064] As illustrated in FIG. 3, the edge binder 25 includes an edge-binder movement assembly 47. The edge-binder movement assembly 47 moves the edge binder 25, specifically, the liquid applier 31 and the crimper 32, in the main scanning direction along a downstream end in the conveyance direction of the sheet P placed on the internal tray 22. The edge-binder movement assembly 47 includes, for example, the base 48, a guide shaft 49, the edge-bindermovement motor 50, and a driving force transmission assembly 551 that transmits the driving force of the edge-binder movement motor 50 to the base 48, and a standby position sensor 540 (see FIG. 11).

[0065] The liquid applier 31 and the crimper 32 are attached to the base 48 such that the liquid applier 31 and the crimper 32 are adjacent to each other in the main scanning direction. As illustrated in FIG. 4, the guide shaft 49 is held by multiple guide shaft brackets 49a disposed in the main scanning direction at a position on the upstream side of a binding assembly base 116 in the conveyance direction of the sheet P. As illustrated in FIG. 3, the guide shaft 49 extends in the main scanning direction on the binding assembly base 116. The guide rail 115 is disposed in the main scanning direction on the downstream side of the binding assembly base 116 in the conveyance direction of the sheet P. As illustrated in FIG. 4, the guide rail 115 includes a fitting target portion 115a that fits to a fitting portion 48a of the base 48 in the main scanning direction. In other words, the base 48 is movably held by the guide shaft 49 and the guide rail 115 in the main scanning direction on the binding assembly base 116.

[0066] The edge-binder movement motor 50 generates a driving force to move the edge binder 25. The driving force transmission assembly 551 transmits the driving force of the edge-binder movement motor 50 to the base 48 via pulleys 551a and 551b, a timing belt 551c, and a fastening portion 48b that fastens the base 48 and the timing belt 551c. As a result, the liquid applier 31 and the crimper 32 integrated by the base 48 move in the main scanning direction along the guide shaft 49.

[0067] The edge-binder movement motor 50 according to the present embodiment is, for example, a servo motor that can stop the edge binder 25 at a target position without returning the edge binder 25 to an origin position (e.g., a standby position HP described below) every time the edge binder 25 is moved. The target position of the edge binder 25 is a position at which the binding process is performed by the crimper 32 on a sheet bundle Pb. In a case where the binding process is performed at a plurality of positions when one sheet bundle Pb is formed, the binding positions are denoted as, for example, a first binding position Bia and a second binding position B2a (see FIGS. 18 to 20C, 22A to 25, and 27 to 28B). Details of the binding position will be described later.

[0068] The post-processing apparatus 3 further includes a standby position sensor 540 and an encoder sensor 541. The standby position sensor 540 is, for example, a light- shielding optical sensor (see FIG. 11) to detect that the edge binder 25 has reached a standby position (or home position) HP (see FIG. 16A). The encoder sensor 541 (see FIG. 11) is attached to an output shaft of the edge-binder movement motor 50. The controller 100b, which is described below, detects that the edge binder 25 has reached the standby position HP, based on a detectionresult of the standby position sensor 540. The controller 100b also counts pulse signals output from the encoder sensor 541 to ascertain the current position of the edge binder 25 moved from the standby position HP.

[0069] However, a specific method of stopping the edge binder 25 at the target position without returning the edge binder 25 to the origin position is not limited to the above-described example. As another example, the post-processing apparatus 3 may include a sensor that detects that the edge binder 25 has reached a predetermined target position.

[0070] In other words, the edge-binder movement assembly 47 can move the edge binder 25 by the shortest distance between the position at which the 31 faces the first binding position B 1 and the position at which the liquid applier 31 faces the second binding position B2 without passing through the standby position HP. The edge -binder movement assembly 47 can move the edge binder 25 by the shortest distance between the position at which the crimper 32 faces the first binding position B 1 and the position at which the crimper 32 faces the second binding position B2 without passing through the standby position HP. Further, the edge-binder movement assembly 47 can move the edge binder 25 by the shortest distance between the position at which the liquid applier 31 faces the first binding position B 1 (or the second binding position B2) and the position at which the crimper 32 faces the first binding position B 1 (or the second binding position B2) without passing through the standby position HP.

[0071] In the above description, the edge binder 25 has a configuration of moving along the guide shaft 49 with the crimper 32 and the liquid applier 31 being integrated. However, the present disclosure is not limited to the above-described configuration. For example, the crimper 32 and the liquid applier 31 may have a configuration of moving separately from and independent of each other.

[0072] The position (liquid application position) to which liquid is applied on a sheet P or a sheet bundle Pb by the liquid applier 31 corresponds to the binding position on the sheet bundle Pb to be crimped by the crimper 32. For this reason, in the following description, the first liquid application position and the second liquid application position are also denoted by the same symbols (e.g., B 1 and B2) as the first binding position and the second binding position, respectively, as described above.

[0073] A description is given below of an edge binder 25' according to a modification.Specifically, a description is given of an edge binder 25' as a modification of the edge binder 25 included in the post-processing apparatus 3 with reference to FIGS. 6 to 8C. A difference of the edge binder 25' from the edge binder 25 according to the first embodiment is that the liquid applier 31 and the crimper 32 are integrated as a single unit. In the followingdescription, identical or similar components to those of the edge binder 25 according to the first embodiment are denoted by identical or similar reference signs, and redundant descriptions thereof may be omitted.

[0074] FIG. 6 is a schematic view of the edge binder 25' viewed from the upstream side in the conveyance direction. FIG. 7 A is a perspective view of a liquid application crimper 310. FIG. 7B is a cross-sectional view of the liquid application crimper 310 taken along line A-A in FIG. 7A. FIG. 7C is a plan view of the upper crimping teeth 32a of FIG. 7A as viewed from the side at which the lower crimping teeth 32b are disposed. FIGS. 8 A, 8B, and 8C illustrate a liquid application operation and a crimping operation performed by the liquid application crimper 310 and are schematic views of the liquid application crimper 310 viewed from the downstream side in the conveyance direction.

[0075] As illustrated in FIG. 6, the edge binder 25' includes the liquid application crimper 310 in which the liquid applier 31 and the crimper 32, which is an example of a post-processing device, of the edge binder 25 according to the first embodiment are integrated as a single unit. The liquid application crimper 310 is disposed downstream from the internal tray 22 in the conveyance direction.

[0076] The liquid application crimper 310 applies liquid LQ stored in the first liquid storage tank 43 to the sheet P or the sheet bundle Pb placed on the internal tray 22. The liquid application crimper 310 can be moved in the main scanning direction by the driving force that is transmitted from the edge-binder movement motor 50 to the base 48 by the driving force transmission assembly 551. The liquid application crimper 310 includes the upper pressure plate 34, the upper crimping teeth 32a, the lower crimping teeth 32b, a liquid-applicationcrimper movement assembly 350, and a liquid supply assembly 360. Components of the liquid application crimper 310 are held by the liquid application frame 31a and the base 48.

[0077] A liquid-application-crimper pivot motor 56T provided with a drive transmission gear 561a' is fixed to a bottom face of the liquid application frame 31a. The liquid-application-crimper pivot motor 56T and the drive transmission gear 561a' are held by the base 48 on which the liquid application frame 31a is disposed, so as to be rotatable in the forward and reverse directions. The drive transmission gear 561a' meshes with an output gear 56a' of a liquidapplication-crimper pivot motor 56'. The liquid application crimper 310 can be rotated in the forward and reverse directions about the liquid-application-crimper pivot motor 56 T on the base 48 by a driving force transmitted from the liquid-application-crimper pivot motor 56' to the liquid-application-crimper pivot motor 56 T via the output gear 56a' and the drive transmission gear 561a'.

[0078] The liquid-application-crimper movement assembly 350 moves the upper pressure plate 34, the base plate 40, and the upper crimping teeth 32a in cooperation with each other in the thickness direction of the sheet P or the sheet bundle Pb by an electric cylinder 370. The base plate 40 holds the upper crimping teeth holder 32al and the upper crimping teeth 32a via a holder 46a. The base plate 40 movably holds the upper pressure plate 34 via the columns 41a and 41b. The base plate 40 is attached to the distal end of a rod 371 of the electric cylinder 370 via a connecter 401.

[0079] The columns 41a and 41b hold the upper pressure plate 34 at lower ends of the columns 41a and 41b. The coil springs 42a and 42b are externally inserted into the columns 41a and 41b between the base plate 40 and the upper pressure plate 34. The coil springs 42a and 42b bias the upper pressure plate 34 and the columns 41a and 41b in a direction away from the base plate 40.

[0080] The liquid supply assembly 360 includes the first liquid storage tank 43, a liquid supply pump 431, and a first liquid supply passage 45'. The liquid supply pump 431 supplies the liquid LQ to the liquid reservoir 320 disposed in the upper crimping teeth holder 32al as illustrated in FIG. 7A via the first liquid supply passage 45'. The first liquid supply passage 45' is coupled to the liquid supply pump 431 at the base end and to the liquid reservoir 320 at the tip end. The first liquid supply passage 45' includes a long and elastic member.

[0081] As illustrated in FIG. 7B, the upper crimping teeth 32a are integrated with the upper crimping teeth holder 32al. The upper crimping teeth holder 32al is provided with the liquid reservoir 320 and a liquid supply passage 321 that supplies the liquid LQ stored in the liquid reservoir 320 to the upper crimping teeth 32a. The surface of the upper crimping teeth 32a is subjected to hydrophilic treatment so that the liquid LQ that is supplied through the liquid supply passage 321 uniformly spreads over the surface of the upper crimping teeth 32a. On the other hand, the portion of the upper crimping teeth holder 32al other than the upper crimping teeth 32a is subjected to hydrophobic treatment so that the liquid LQ efficiently spreads over the surface of the upper crimping teeth 32a.

[0082] As illustrated in FIG. 6, the lower crimping teeth 32b are integrated with a lower crimping teeth holder 32b 1, which is a part of the liquid application frame 31a. The lower crimping teeth 32b are attached to the base 48 via the lower crimping teeth holder 32b 1.

[0083] A description is given below of the liquid application operation and the crimping operation of the liquid application crimper 310 with reference to FIGS. 8A, 8B, and 8C. In the process of supplying a sheet P to the internal tray 22, as illustrated in FIG. 8A, the upper crimping teeth 32a and the lower crimping teeth 32b are separated from each other. When the sheet P isplaced on the internal tray 22, the electric cylinder 370 is contracted to move the upper crimping teeth 32a and the upper pressure plate 34 toward the sheet P. Then, as illustrated in FIG. 8B, the upper pressure plate 34 first comes into contact with the sheet P, and then the upper crimping teeth 32a pass through the through-hole 34a of the upper pressure plate 34 and come into contact with the sheet P. At this time, since the liquid LQ is spread over the surfaces of the upper crimping teeth 32a, bringing the upper crimping teeth 32a into contact with the sheet P allows the liquid to be applied to the liquid application position on the sheet P. When liquid application to the liquid application position is completed, the electric cylinder 370 is extended to separate the upper crimping teeth 32a and the upper pressure plate 34 from the sheet P. The above-described contact and separation operation (liquid application operation) of the upper crimping teeth 32a and the upper pressure plate 34 with respect to the sheets P is repeatedly performed on sheets P of the sheet bundle Pb.

[0084] When the sheet bundle Pb including a predetermined number of sheets P is placed on the internal tray 22, the electric cylinder 370 is further contracted to move the upper crimping teeth 32a toward the lower crimping teeth 32b. Then, as illustrated in FIG. 8C, the upper crimping teeth 32a further moves toward the lower crimping teeth 32b, with the sheet bundle Pb sandwiched between the upper crimping teeth 32a and the lower crimping teeth 32b. Thus, the upper crimping teeth 32a and the lower crimping teeth 32b press and deform the sheet bundle Pb to crimp and bind the sheet bundle Pb (crimping operation).

[0085] A description is given of the staple binder 55.Details of the staple binder 55 having the function of executing the stapling process are described below. FIG. 9 is a schematic diagram illustrating the staple binder 55, viewed from the upstream side of the staple binder 55 in the conveyance direction. The staple binder 55 includes a stapler 62 that binds the sheet bundle Pb with staples. The stapler 62 is disposed downstream from the internal tray 22 in the conveyance direction of the sheet P and spaced apart from the edge binder 25 in the main scanning direction.

[0086] The stapler 62 serving as a post-processing device has a configuration of performing so-called "staple binding" to bind a sheet bundle Pb with a staple(s). More specifically, the stapler 62 includes a stapling-part drive motor 62d (see FIG. 11) that drives a stapling part 62a. The stapling part 62a binds the sheet bundle Pb by causing the binding staple loaded in the stapling part 62a to penetrate the sheet bundle Pb by the driving force of the stapling-part drive motor 62d. The configuration of the stapler 62 is already known, and thus detailed descriptions thereof will be omitted.

[0087] As illustrated in FIG. 9, the staple binder 55 includes a staple -binder movement assembly 77. The staple-binder movement assembly 77 moves the staple binder 55 in the main scanningdirection along a downstream end in the conveyance direction of the sheet P or the sheet bundle Pb placed on the internal tray 22. The staple-binder movement assembly 77 includes, for example, a base 78, the guide shaft 49, a staple-binder movement motor 80, and a driving force transmission assembly 81. The driving force transmission assembly 81 transmits a driving force of the staple-binder movement motor 80 to the base 78 via pulleys 81a and 81b, a timing belt 81c, and a fastening portion 78a that fastens the base 78 and the timing belt 81c. A stapler shaft 83 including a drive transmission gear 83a is fixed to a bottom face of a stapling frame 62b that holds the components of the stapler 62.

[0088] The stapler shaft 83 and the drive transmission gear 83a are held by the base 78 on which the stapling frame 62b is disposed, so as to be rotatable in the forward and reverse directions. The drive transmission gear 83a meshes with an output gear 82a of a stapler pivot motor 82. The stapler 62 is rotatable in the forward and reverse directions about the stapler shaft 83 on the base 78 by a driving force transmitted from the stapler pivot motor 82 to the stapler shaft 83 via the output gear 82a and the drive transmission gear 83a.

[0089] The edge binder 25 and the staple binder 55 are supported by the common guide shaft 49. In other words, the edge-binder movement assembly 57 and the staple-binder movement assembly 77 move the edge binder 25 and the staple binder 55 in the main scanning direction along the common guide shaft 49. Further, the edge-binder movement assembly 57 and the staple-binder movement assembly 77 can move the edge binder 25 and the staple binder 55 separately.

[0090] FIG. 10 illustrates a staple binder 55' as a modification of the staple binder 55. More specifically, FIG. 10 is a schematic view of the staple binder 55' as viewed from the upstream side in the conveyance direction. The staple binder 55' is different from the staple binder 55 in that the staple binder 55' includes a second liquid applier 612 in addition to the stapler 62. As illustrated in FIG. 10, the staple binder 55' includes the second liquid applier 612 and the stapler 62. The second liquid applier 612 and the stapler 62 are disposed adjacent to each other in the main scanning direction on the downstream side of the internal tray 22 in the conveyance direction.

[0091] The second liquid applier 612 executes “liquid application” of applying liquid stored in a second liquid storage tank 73 to the sheet P or the sheet bundle Pb placed on the internal tray 22. A given area including a position to which the liquid is applied on the sheet P or the sheet bundle Pb by the second liquid applier 612 corresponds to a binding position to be stapled by the stapler 62. As illustrated in FIG. 10, the second liquid applier 612 includes a second lower pressure plate 63, a second upper pressure plate 64, a second liquid- applier movement assembly 65, and a second liquid application assembly 66.

[0092] The second liquid- applier movement assembly 65 includes, for example, a second liquidapplication-unit movement motor 67, a second trapezoidal screw 68, a second nut 69, a second base plate 70, second columns 711a and 711b, and second coil springs 721a and 721b. The second liquid application assembly 66 includes the second liquid storage tank 73, a second liquid application member 74, a second liquid supply portion 75, and a second joint 76.

[0093] Since the second liquid application assembly 66 has a common structure with the liquid application assembly 36 of the liquid applier 31 described with reference to FIGS. 3 and 4, redundant descriptions thereof will be omitted unless otherwise required. Since the configuration of the stapler 62 illustrated in FIG. 10 is like the configuration of the stapler 62 illustrated in FIG. 9, a detailed description thereof is omitted below unless otherwise required. Since the second liquid applier 612 and the liquid applier 31 that are illustrated in FIG. 3 have common pivot mechanisms, redundant descriptions thereof will be omitted unless otherwise required. The pivot mechanism of the second liquid applier 612 includes a liquid-applier pivot motor 563, an output gear 563a, a drive transmission gear 562a, and a liquid-applier rotation shaft 562.

[0094] In the binding process, the staple binder 55' that is illustrated in FIG. 10 performs the liquid application process on the sheet P to loosen and soften the binding position, allowing the staple to easily pass through the sheet bundle Pb. As a result, the number of sheets to be bound per sheet bundle Pb can be increased as compared with a case where the stapling process is performed without performing the liquid application.

[0095] A description is given below of control blocks of the post-processing apparatus 3. Specifically, a configuration of control blocks of the post-processing apparatus 3 according to the first embodiment is described with reference to FIG. 11. FIG. 11 is a diagram illustrating a hardware configuration for executing control processing in the post-processing apparatus 3. As illustrated in FIG. 11, the post-processing apparatus 3 includes a central processing unit (CPU) 101, a random-access memory (RAM) 102, a read-only memory (ROM) 103, a hard disk drive (HDD) 104, and an interface (I / F) 105. The CPU 101, the RAM 102, the ROM 103, the HDD 104, and the PF 105 are connected to each other via a common bus 109.

[0096] The CPU 101 is an arithmetic device and controls the overall operation of the post-processing apparatus 3. The RAM 102 is a volatile storage medium that allows high speed reading and writing of data, and is used as a working area when the CPU 101 processes information. The ROM 103 is a read-only non-volatile storage medium, and stores programs such as firmware. The HDD 104 is a non-volatile storage medium that allows data to be read and written andhas a relatively large storage capacity. The HDD 104 stores, for example, an operating system (OS), various control programs, and application programs.

[0097] By an arithmetic function of the CPU 101, the post-processing apparatus 3 processes, for example, a control program stored in the ROM 103 and an information processing program (application program) loaded into the RAM 102 from a storage medium such as the HDD 104. Such processing configures a software controller including various functional modules of the post-processing apparatus 3. The software controller thus configured cooperates with hardware resources of the post-processing apparatus 3 to construct functional blocks that implement functions of the post-processing apparatus 3. In other words, the CPU 101, the RAM 102, the ROM 103, the HDD 104, and the I / F 105 constitute at least part of a controller 100b, which is an example of a control device, to control the operation of the post-processing apparatus 3.

[0098] The I / F 105 is an interface that connects the conveyance roller pairs 10, 11, 14, and 15, the switcher 20, the side fences 24L and 24R, the contact-separation motor 32d, the crimpingteeth slide motor 32e, the crimper pivot motor 56, the liquid-applier movement motor 37, the liquid- applier pivot motor 563, the edge-binder movement motor 50, the stapling-part drive motor 62d, the stapler pivot motor 82, the staple -binder movement motor 80, the movement sensor 40a, the liquid-level sensor 43a, the standby position sensor 540, the encoder sensor 541, and the operation panel 110 to the common bus 109.

[0099] The controller 100b controls, via the I / F 105, the operations of the conveyance roller pairs 10, 11, 14, and 15, the switcher 20, the side fences 24L and 24R, the contact- separation motor 32d, the crimping-teeth slide motor 32e, the crimper pivot motor 56, the liquid-applier movement motor 37, the liquid-applier pivot motor 563, the edge-binder movement motor 50, the stapling-part drive motor 62d, the stapler pivot motor 82, and the staple -binder movement motor 80. The controller 100b acquires detection results from the movement sensor 40a, the liquid-level sensor 43a, the standby position sensor 540, and the encoder sensor 541. Although FIG. 11 illustrates only the components related to the edge binder 25 and the staple binder 55 that perform the edge binding, the components related to the saddle binder 28 that performs the saddle binding are also controlled by the controller 100b.

[0100] As illustrated in FIG. 1, the image forming apparatus 2 includes the operation panel 110. The operation panel 110 includes an operation section that receives instructions input by an operator and a display (which is an example of a notifier) that notifies the operator of information. The operation device includes, for example, hard keys and a touch screen overlaid on the display. The operation panel 110 acquires information from the user through the operation section and provides information to the user through the display. A specificexample of the notifier is not limited to the display and may be a light-emitting diode (LED) lamp or a speaker. The post-processing apparatus 3 may include an operation panel 110 similar to the above-described operation panel 110 of the image forming apparatus 2.

[0101] As described above, the post-processing apparatus 3 according to the present embodiment includes the edge binder 25 that can perform post-processing (a crimping process or a stapling process) after liquid application. When the number of sheets P included in a sheet bundle Pb is small, the edge binder 25 can also perform crimping without performing liquid application (i.e., a crimping process only by the crimper 32), similarly to a crimping process of the related art.

[0102] The edge binder 25 has a configuration in which the liquid applier 31 and the crimper 32 are movable in the main scanning direction by the crimping -teeth slide assembly 322 and / or the edge-binder movement assembly 47. Accordingly, a plurality of crimping operations can be performed by moving the liquid application position of the liquid applier 31 and / or the binding position of the crimper 32 in the main scanning direction. As a result, the crimp marks formed by the binding operation of the upper crimping teeth 32a and the lower crimping teeth 32b can be formed adjacent to each other, thus allowing the binding strength of the sheet bundle Pb to be enhanced.

[0103] A description is given below of a second embodiment.A configuration and processing of the post-processing apparatus 3 according to the second embodiment is described with reference to FIGS. 12A to 18. Detailed descriptions will be omitted of common features with the first embodiment. The following description is mainly given of differences of the second embodiment from the first embodiment. The second embodiment may be combined with other embodiments without departing from the spirit of the present disclosure.

[0104] FIGS. 12A, 12B, 12C, and 12D are diagrams illustrating a contact-separation assembly 90 that move the upper crimping teeth 32a and the lower crimping teeth 32b close to and away from each other. The contact-separation assembly 90 is a mechanism that move the upper crimping teeth 32a and the lower crimping teeth 32b close to and away from each other by a driving force of the contact- separation motor 32d. The contact- separation assembly 90 includes, for example, an upper arm 91, a lower arm 92, a coil spring 93, which is an example of a biasing member, a drive gear 94, a driven gear 95, an eccentric cam 96, a rotation shaft 97, and a home position sensor 98 as illustrated in FIGS. 12A, 12B, 12C, and 12D.

[0105] The upper arm 91 supports the upper crimping teeth 32a at one end. The upper arm 91 is supported by the lower arm 92 so that the upper arm 91 be rotatable about the rotation shaft97 extending in the main scanning direction. The lower arm 92 supports the lower crimping teeth 32b at a position where the lower arm 92 can face the upper crimping teeth 32a. The lower arm 92 is fixed to the crimper frame 32c. Rotating the upper arm 91 about the rotation shaft 97 causes the upper crimping teeth 32a and the lower crimping teeth 32b to move close to and away from each other. The coil spring 93 biases the upper arm 91 in a direction in which the upper crimping teeth 32a moves away from the lower crimping teeth 32b.

[0106] The drive gear 94 is rotated counterclockwise in FIGS. 12A to 12D by the driving force of the contact- separation motor 32d. The driven gear 95 is meshed with the drive gear 94. The eccentric cam 96 is coupled to the driven gear 95 at a position off the center and rotates together with the driven gear 95. The outer peripheral surface of the eccentric cam 96 abuts on the other end of the upper arm 91 (e.g., an end opposite to an end supporting the upper crimping teeth 32a with respect to the rotation shaft 97).

[0107] When the eccentric cam 96 is in the state illustrated in FIG. 12A, the upper crimping teeth 32a and the lower crimping teeth 32b are away from each other by the biasing force of the coil spring 93. When the eccentric cam 96 rotates from the state illustrated in FIG. 12A, the upper arm 91 rotates in a direction in which the upper crimping teeth 32a and the lower crimping teeth 32b are brought into contact with each other against the biasing force of the coil spring 93. When the eccentric cam 96 reaches the state of FIG. 12C through the state of FIG. 12B, the upper crimping teeth 32a and the lower crimping teeth 32b engage with each other. When the eccentric cam 96 further rotates from the state illustrated in FIG. 12C, the upper arm 91 is rotated by the biasing force of the coil spring 93 in a direction in which the upper crimping teeth 32a and the lower crimping teeth 32b move away from each other. As a result, the eccentric cam 96 returns to the state of FIG. 12A via the state of FIG. 12D.

[0108] In the following description, the position of the upper crimping teeth 32a in FIG. 12A is denoted as "top dead point", and the position of the upper crimping teeth 32a in FIG. 12B is denoted as "bottom dead point." In other words, the upper crimping teeth 32a at the top dead point are farthest from the lower crimping teeth 32b. The upper crimping teeth 32a at the bottom dead point engage with the lower crimping teeth 32b, and the pressing force to a sheet bundle Pb becomes maximum. When the eccentric cam 96 makes one rotation in the clockwise direction in FIGS. 12A to 12D, the upper crimping teeth 32a return from the top dead point to the bottom dead point and then back to the top dead point. FIGS. 12 A, 12B, 12C, and 12D illustrate states in which the eccentric cam 96 is rotated by 90°.

[0109] The home position sensor 98 detects that the upper crimping teeth 32a are positioned at the top dead point. The home position sensor 98 includes a sensor fixed to the crimper frame 32c and a detection target element that rotates together with the eccentric cam 96. When theupper crimping teeth 32a are at the top dead point, the sensor detects the detection target element. The controller 100b can grasp the position of the upper crimping teeth 32a (i.e., the rotation angle of the eccentric cam 96) by counting the pulse signal of the encoder sensor 99 of the contact- separation motor 32d from the time point when the home position sensor 98 detects that the upper crimping teeth 32a reach the top dead point.

[0110] A description is given below of control blocks of the post-processing apparatus 3.FIG. 13 is a diagram illustrating a hardware configuration of the post-processing apparatus 3 according to the second embodiment. FIG. 13 is different from FIG. 11 in that the crimpingteeth slide motor 32e, the crimper pivot motor 56, the liquid-applier pivot motor 563, the stapling-part drive motor 62d, the stapler pivot motor 82, and the staple-binder movement motor 80 are omitted, and a home position sensor 98 and an encoder sensor 99 are added. On the other hand, other configurations are common between FIG. 11 and FIG. 13.

[0111] FIG. 14A is an example of a pressing-hold setting screen and FIGS. 14B and 14C are examples of data of a pressing-hold control table. The pressing-hold setting screen illustrated in FIG. 14A is displayed on the operation panel 110 and receives a user operation. The pressing-hold control tables illustrated in FIGS. 14B and 14C are stored in the HDD 104.

[0112] As illustrated in FIG. 14A, the pressing-hold setting screen includes a radio button for instructing not to execute the pressing-hold control (i.e., turning off the pressing-hold control), a radio button for instructing to manually set the threshold number of sheets used for the pressing-hold control, a radio button for instructing to automatically set the threshold number of sheets used for the pressing-hold control, a text box for receiving an input of the threshold number of sheets, a radio button for receiving an input of the holding time (i.e., execution time of the pressing-hold control), a “SET” icon, and a “CANCEL” icon.

[0113] As an example, the user selects the radio button for manual setting, inputs desired values to text boxes for the threshold number of sheets and the holding time, and selects the “SET” icon. Thus, the controller 100b executes the pressing-hold control using the threshold number of sheets and the holding time input in the text boxes. On the other hand, when the radio button for instructing not to execute the pressing-hold control is selected, the pressing-hold control is not executed. In other words, the controller 100b switches whether to execute the pressing-hold control according to the user operation received by the operation panel 110.

[0114] As another example, the user selects the radio button of the automatic setting, inputs a desired value in the text box of the holding time, and selects the "SET" icon. Accordingly, the controller 100b executes the pressing-hold control using the threshold number of sheetsdetermined using the pressing-hold control table illustrated in FIG. 14B or 14C and the holding time input in the text box.

[0115] The pressing-hold control tables illustrated in FIGS. 14B and 14C are tables for setting whether the pressing -hold control is to be executed (i.e., turned on) or to be unexecuted (i.e., turned off) for each combination of the threshold number of sheets (e.g., 5, 10, 15, or 20) and the thickness of the sheet P (extremely thin, thin, medium, thick, or extremely thick). Further, FIG. 14B corresponds to plain paper, and FIG. 14C corresponds to recycled paper. The controller 100b switches whether to execute the pressing-hold control based on at least one of the medium information of a sheet bundle Pb (e.g., the number of sheets P included in the sheet bundle Pb, the thickness of the sheet P, and the type of the sheet P). The type of the sheet P refers to, for example, high-quality paper, plain paper, or recycled paper.

[0116] In the example of FIG. 14B, the threshold number of sheets in the case of the thickness "extremely thick" of the sheet P is five, the threshold number of sheets in the case of the thickness "thick" of the sheet P is 10, the threshold number of sheets in the case of the thickness "medium" of the sheet P is 15, the threshold number of sheets in the case of the thickness "thin" of the sheet P is 20, and the threshold number of sheets in the case of the thickness "extremely thin" of the sheet P is infinite (i.e., the pressing-hold control is not executed). In the example of FIG. 14C, the threshold number of sheets in the case of the thickness "extremely thick" of the sheet P is 10, the threshold number of sheets in the case of the thickness "thick" of the sheet P is 15, the threshold number of sheets in the case of the thickness "medium" of the sheet P is 20, and the threshold number of sheets in the cases of the thickness "thin" and the thickness "extremely thin" of the sheet P is infinite (i.e., the pressinghold control is not executed).

[0117] In other words, in the example of FIGS. 14B and 14C, the threshold number of sheets decreases as the thickness of the sheet P increases. In the example of FIGS. 14B and 14C, the threshold number of sheets decreases as the rigidity of the sheet P (e.g., plain paper > recycled paper) increases. However, the relation between the medium information and the threshold number of sheets is not limited to the example of FIGS. 14B and 14C.

[0118] A description is given below of a binding process.Specifically, a description is given below of a binding process executed by the edge binder 25 included in the post-processing apparatus 3. FIG. 15 is a flowchart of the binding process. FIGS. 16A, 16B, and 16C are diagrams illustrating the positions of the liquid applier 31, which is an example of a liquid applier, and the crimper 32, which is an example of a crimper, during the binding process. The position (i.e., liquid application position) to which liquid is applied on a sheet P or a sheet bundle Pb by the liquid applier 131 corresponds to the bindingposition on the sheet bundle Pb to be crimped by the crimper 32. For this reason, in the following description, the liquid application position and the binding position are denoted by the same reference sign.

[0119] For example, the controller 100b starts the binding process illustrated in FIG. 15 when the controller 100b acquires an execution command of the binding process from the image forming apparatus 2. In the following description, the execution command of the binding process may be referred to as a “binding command.” The binding command includes, for example, the type of the sheet P (i.e., information affecting the spread of liquid, such as material and thickness), the number of sheets P of the sheet bundle Pb, the number of sheet bundles Pb to be bound, and the binding position on the sheet bundle Pb. In the following description, the number of sheets P included in the sheet bundle Pb may be referred to as “given number” whereas the number of sheet bundles Pb to be bound may be referred to as “requested number of copies.” The liquid applier 31 and the crimper 32 are assumed to be located at a standby position HP (FIG. 16A) that is a position shifted in the width direction from the sheets P placed on the internal tray 22 at the start of the binding process.

[0120] In step S1501, as illustrated in FIG. 16B, the controller 100b drives the edge-binder movement motor 50 to move the edge binder 25 in the main scanning direction so that the liquid applier 31 faces the liquid application position B instructed by the binding command. The controller 100b executes the operation of step S1501 before a first sheet P is conveyed to the internal tray 22 by the conveyance roller pairs 10, 11, 14, and 15.

[0121] In step S1502, the controller 100b rotates the conveyance roller pairs 10, 11, 14, and 15 to store the sheet P, on which the image has been formed by the image forming apparatus 2, onto the internal tray 22. In step S1502, the controller 100b also moves the side fences 24L and 24R to align the position of the sheet bundle Pb placed on the internal tray 22 in the main scanning direction. In short, the controller 100b performs so-called jogging.

[0122] In step S1503, the controller 100b causes the liquid applier 31 facing the liquid application position B to apply liquid to the liquid application position B of the sheet P placed on the internal tray 22 in the immediately preceding step S1502, based on the liquid application control data adjusted in advance. In other words, the controller 100b drives the liquid- applier movement motor 37 to bring the liquid application member 44 into contact with the liquid application position B on the sheet P placed on the internal tray 22 (see FIG. 16B). Steps S1501 and S1503 may be omitted.

[0123] In step S1504, the controller 100b determines whether the number of sheets P stored in the internal tray 22 has reached the given number instructed by the binding command. When thecontroller 100b determines that the number of sheets P stored in the internal tray 22 has not reached the given number N (NO in step S1504), the controller 100b executes the operations of steps S1502 and S1503 again. In other words, the controller 100b executes the processing of steps S1502 and S1503 each time the sheet P is conveyed to the internal tray 22 by the conveyance roller pairs 10, 11, 14, and 15. The liquid application of the liquid applier 31 may be performed on all or a part of the sheets P included in the sheet bundle Pb. For example, the controller 100b may cause the liquid applier 31 to apply liquid to sheets P at an interval of one sheet in n sheets.

[0124] When the controller 100b determines that the number of sheets P stored in the internal tray 22 has reached the given number of sheets (YES in step S1504), in step S1505, the controller 100b drives the edge-binder movement motor 50 to move the edge binder 25 in the main scanning direction such that the crimper 32 faces the binding position B as illustrated in FIG. 16C.

[0125] In step S1506, the controller 100b executes the crimping process. The crimping process is a process of causing the crimper 32 to perform crimping and binding on the sheet bundle Pb placed on the internal tray 22. Specifically, the controller 100b drives the contact-separation motor 32d to cause the upper crimping teeth 32a and the lower crimping teeth 32b to pinch the binding position B on the sheet bundle Pb placed on the internal tray 22. Accordingly, the sheet bundle Pb is pressed and deformed between the upper crimping teeth 32a and the lower crimping teeth 32b, and is crimped and bound. Details of the crimping process will be described later with reference to FIGS. 16A to 16C. In step S1507, the controller 100b causes the conveyance roller pair 15 to eject the sheet bundle Pb thus crimped and bound by the crimper 32 to the ejection tray 26.

[0126] The sheet bundle Pb placed on the internal tray 22 has a crimping area (corresponding to the binding position B) pinched between the upper crimping teeth 32a and the lower crimping teeth 32b in step S1506. The crimping area overlaps a liquid application area (corresponding to the liquid application position B) contacted by a distal end (tip portion) of the liquid application member 44 in step S1503. In other words, the crimper 32 crimps an area to which liquid is applied by the liquid applier 31 on the sheet bundle Pb placed on the internal tray 22. The crimping area that is pinched by the upper crimping teeth 32a and the lower crimping teeth 32b may completely or partially overlaps the liquid application area contacted by the distal end of the liquid application member 44, to obtain a sufficient binding strength.

[0127] In step S1508, the controller 100b determines whether the number of sheet bundles Pb thus ejected has reached the requested number of copies indicated by the binding command. When the controller 100b determines that the number of sheet bundles Pb thus ejected has notreached the requested number of copies (NO in step S1508), the controller 100b executes the operations of step S1502 and its subsequent steps again. In other words, when the controller 100b determines that the number of sheet bundles Pb thus ejected has not reached the requested number M of copies (NO in step S1508), the controller 100b repeats the operations of steps S1502 to S1507 until the number of sheet bundles Pb ejected to the ejection tray 26 reaches the requested number of copies.

[0128] When the controller 100b determines that the number of sheet bundles Pb ejected to the ejection tray 26 has reached the requested number of copies (YES in step S1508), in step S1509, the controller 100b drives the edge-binder movement motor 50 to move the edge binder 25 to the standby position HP as illustrated in FIG. 16A.

[0129] A description is given below of a crimping process.FIG. 17 is a flowchart of a crimping process. FIG. 18 is a graph illustrating a relation between a processing time of the crimping process and a pressing force applied to a sheet bundle Pb. It is assumed that the upper crimping teeth 32a are positioned at the top dead point as illustrated in FIG. 12A at the time of starting the crimping process.

[0130] First, the controller 100b determines whether to execute the pressing-hold control in step S1701. The pressing-hold control is control for holding a state in which a sheet bundle Pb is pressed and deformed by the pair of binding teeth 32a and 32b for a predetermined holding time. More specifically, the pressing-hold control is control for holding a state in which the pair of binding teeth 32a and 32b are closest to each other for a predetermined time. The controller 100b determines, for example, whether a radio button (indicating “OFF”) for instructing not to execute the pressing-hold control is selected on the pressing-hold setting screen illustrated in FIG. 14A.

[0131] When the controller 100b determines that the pressing-hold control is not to be executed (“OFF” in step S 1701), in step S1702, the controller 100b starts the rotation of the contactseparation motor 32d. The controller 100b continues the rotation of the contact- separation motor 32d based on the home position sensor 98 until the eccentric cam 96 makes one rotation (i.e., the upper crimping teeth 32a returns to the top dead point again from the top dead point through the bottom dead point) (NO in S1703). In step S1704, the controller 100b stops the contact- separation motor 32d at the timing when the eccentric cam 96 has made one rotation (YES in step S1703). In other words, in the steps S1702 to S1704, the controller 100b causes the eccentric cam 96 to make one rotation without stopping the contactseparation motor 32d in the middle (i.e., without executing the pressing-hold control). Then, the upper crimping teeth 32a reach the bottom dead point, and thus the sheet bundle Pb is crimped and bound.On the other hand, when the controller 100b determines to execute the pressing-hold control (“ON” in step S1701), in step S1705, the controller 100b compares the number of sheets P included in the sheet bundle Pb with the threshold-value number of sheets. The number of sheets P compared in step S 1705 is equal to the predetermined number of sheets P in step S1504 and is denoted as "the number of sheets to be bound." In step S1705, the controller 100b may use the number of sheets input in the text box of the pressing-hold setting screen, the number of sheets determined using the pressing-hold control table, or a predetermined fixed value. In addition, in a case where the threshold number of sheets is determined using the pressing-hold control table, the number of sheets P, the thickness of the sheet P, and the type of the sheet P may be included in, for example, the binding command.

[0133] When the number of sheets to be bound is less than the predetermined number of sheets (NO in step S1705), the controller 100b executes the processing of steps S1702 to S1704 (i.e., crimping without executing the pressing-hold control).

[0134] On the other hand, when the number of sheets to be bound is equal to or greater than the predetermined number of sheets (YES in step S1705), in step S1706, the controller 100b starts the rotation of the contact- separation motor 32d. The controller 100b continues the rotation of the contact- separation motor 32d until the eccentric cam 96 rotates half a turn (i.e., the upper crimping teeth 32a reaches the bottom dead point) (NO in step S1707) based on the home position sensor 98 and the encoder sensor 99. In step S1708, the controller 100b temporarily stops the contact- separation motor 32d at the timing when the eccentric cam 96 has rotated half a turn (YES in S 1707). Accordingly, the pair of binding teeth 32a and 32b are held in a state of being closest to each other (i.e., a state in which the pressing force against the sheet bundle Pb is at the maximum).

[0135] The controller 100b continues the state in which the contact-separation motor 32d is temporarily stopped until the holding time elapses (NO in step S1709). In other words, the controller 100b executes the pressing-hold control. In step S1709, the controller 100b may use the holding time input to the text box of the pressing-hold setting screen, the holding time of a predetermined fixed value, or the holding time determined based on the medium information.

[0136] In step S1710, the controller 100b resumes the rotation of the contact-separation motor 32d at a timing when the holding time has elapsed after the contact-separation motor 32d is temporarily stopped (YES in step S1709). The controller 100b continues the rotation of the contact- separation motor 32d until the eccentric cam 96 further rotates half a turn (i.e., one rotation in total from step S1706) (NO in step S1703) based on the home position sensor 98.In step S1704, the controller 100b stops the contact-separation motor 32d at the timing when the eccentric cam 96 has made one rotation (YES in step S1703). In other words, in steps S1706 to S1710 and S1703 to S1704, the contact- separation motor 32d is stopped in the middle (i.e., the pressing-hold control is executed), and the eccentric cam 96 is rotated one turn.

[0137] As illustrated in FIG. 18, in the course in which the upper crimping teeth 32a move from the top dead point to the bottom dead point, the pressing force remains at zero until the upper crimping teeth 32a comes into contact with the sheet bundle Pb, and the pressing force gradually increases after the upper crimping teeth 32a comes into contact with the sheet bundle Pb. Further, as the upper crimping teeth 32a is stopped at the bottom dead point until the holding time elapses, the pair of binding teeth 32a and 32b bite into the sheet bundle Pb, thus increasing the binding strength. Further, in the course in which the upper crimping teeth 32a move from the bottom dead point to the top dead point, the pressing force gradually decreases until the upper crimping teeth 32a separate from the sheet bundle Pb, and the pressing force is maintained at zero after the upper crimping teeth 32a separate from the sheet bundle Pb.

[0138] A description is given below of an operation and effect of the second embodiment. According to the second embodiment, switching whether to execute the pressing-hold control allows a sheet bundle Pb to be crimped and bound with an appropriate binding strength according to the state of the sheet bundle Pb. For example, high binding strength is obtained when the number of sheets P is large, and the damage to the sheet bundle Pb or the crimper 32 can be reduced when the number of sheets P is small.

[0139] According to the second embodiment, for example, whether to execute the pressing-hold control may be automatically switched based on the medium information (e.g., the number of sheets P, the thickness of the sheet P, and the type of the sheet P) included in the binding command. Thus, the sheet bundle Pb can be crimped and bound with an appropriate binding strength while reducing the operation burden on the user.

[0140] According to the second embodiment, whether to execute the pressing-hold control or the parameters (e.g., the threshold number of sheets and the holding time) of the pressing-hold control may be switched by the manual operation of the user. Thus, the binding strength desired by the user can be obtained.

[0141] According to the second embodiment, the upper crimping teeth 32a are held in the state of the bottom dead point (i.e., the state in which the pair of binding teeth 32a and 32b are closest to each other), and thus high binding force can be most efficiently obtained.

[0142] A description is given below of a post-processing apparatus 3A according to a third embodiment.The post-processing apparatus 3A according to the third embodiment is described below with reference to FIGS. 19 to 27. In the following description, identical or similar components to those of the first embodiment are denoted by identical or similar reference signs, and redundant descriptions thereof may be omitted.

[0143] The post-processing apparatus 3A according to the third embodiment includes an edge binder 251. The edge binder 251 is different from the edge binder 25 of the post-processing apparatus 3 according to the first embodiment, in which the liquid applier 31 and the crimper 32 are arranged side by side, in that the edge binder 251 includes a crimper 32' and a liquid applier 131 is disposed at an upstream position in a direction in which a sheet P is conveyed. Such a configuration allows a given number of sheets P to be stacked in advance after the liquid application process and conveyed to the crimper 32' of the edge binder 251 disposed at a downstream position in the direction in which the sheet P is conveyed. Accordingly, the productivity of the binding process performed by the crimper 32' is enhanced.

[0144] Since the direction in which the conveyance roller pairs 10, 11, and 14 convey the sheet P is opposite to the “conveyance direction” defined above, the direction in which the conveyance roller pairs 10, 11, and 14 convey the sheet P is defined as a “reverse conveyance direction” in the following description. A direction that is orthogonal to both the opposite conveyance direction and the thickness direction of the sheet P is defined as the “main scanning direction” or the “width direction of the sheet P.”

[0145] The liquid application position to which the liquid is applied on the sheet P or the sheet bundle Pb by the liquid applier 131 corresponds to the binding position on the sheet bundle Pb to be crimped and bound by the crimper 32'. For this reason, in the following description, the liquid application position and the binding position are described with the same reference sign B l.

[0146] FIG. 19 is a diagram illustrating an internal configuration of the post-processing apparatus 3A according to the third embodiment. As illustrated in FIGS. 20A, 20B, and 20C, the edge binder 251 includes the crimper 32'. As illustrated in FIGS. 20A, 20B, and 20C, the crimper 32' and the staple binder 156 are disposed downstream from the internal tray 22 in the conveyance direction. In addition, the crimper 32' and the staple binder 156 are located to face a downstream end, in the conveyance direction, of the sheet bundle Pb placed on the internal tray 22 and is movable in the main scanning direction.

[0147] Further, the crimper 32' and the staple binder 156 are respectively rotatable in the forward and reverse directions about a crimper rotation shaft 340 and a stapler rotation shaft 84 both extending in the thickness direction of the sheet bundle Pb placed on the internal tray 22. In other words, the crimper 32' and the staple binder 156 bind, at any desired angle, any desired position in the main scanning direction on the sheet bundle Pb placed on the internal tray 22 in, for example, corner oblique binding, parallel one-point binding, or parallel two-point binding.

[0148] The crimper 32' presses and deforms the sheet bundle Pb with the serrate upper crimping teeth 32a and the serrate lower crimping teeth 32b to bind the sheet bundle Pb. In the following description, such a binding way may be referred to as “crimping.” In other words, the crimper 32' crimps and binds the sheet bundle Pb or performs the crimping on the sheet bundle Pb. On the other hand, the staple binder 156 passes the staple through a binding position on the sheet bundle Pb placed on the internal tray 22, thus allowing the sheet bundle Pb to be stapled.

[0149] FIGS. 20A, 20B, and 20C are schematic views of the internal tray 22 as viewed from the thickness direction of the sheet bundle Pb. FIG. 21 is a schematic view of the crimper 32' as viewed from the downstream side in the conveyance direction. As illustrated in FIGS. 20A, 20B, and 20C, the crimper 32' and the staple binder 156 are disposed downstream from the internal tray 22 in the conveyance direction. The crimper 32' is movable in the main scanning direction along the surface of the sheet bundle Pb placed on the internal tray 22. The crimper 32' is rotatable in the forward and reverse directions about the crimper rotation shaft 340 extending in the thickness direction of the sheet bundle Pb placed on the internal tray 22.

[0150] Similarly, the staple binder 156 is movable in the main scanning direction of the sheet bundle Pb. The staple binder 156 is rotatable in the forward and reverse directions about the stapler rotation shaft 84 extending in the thickness direction of the sheet bundle Pb. The other components of the staple binder 156 are similar to, even if not the same as, those of the staple binder 55 (see FIG. 9) of the post-processing apparatus 3 according to the first embodiment. For this reason, a detailed description thereof is omitted.

[0151] As illustrated in FIG. 21, the crimper 32' includes a guide rail 337 extending in the main scanning direction at a position downstream from the internal tray 22 in the conveyance direction. The crimper 32' includes a crimper movement motor 238 as a driving source. A base 48 supporting a crimper frame 32c has a fastening portion 48b for a timing belt 240c at the bottom of the base 48. The driving force of the crimper movement motor 238 is transmitted to the base 48 by the drive transmission assembly 240 that includes the pullies 240a and 240b, the timing belt 240c, and the fastening portion 48b. By so doing, the crimper32' is moved in the main scanning direction along the surface of the sheet bundle Pb placed on the internal tray 22, in other words, along the guide rail 337. Further, the crimper rotation shaft 340 is fixed to a bottom face of the crimper frame 32c that holds the components of the crimper 32'.

[0152] The crimper rotation shaft 340 and the drive transmission gear 340a are held by a base 48 on which the crimper frame 32c is disposed, so as to be rotatable in the forward and reverse directions. The drive transmission gear 340a meshes with an output gear 239a of a crimper pivot motor 239. When the driving force of the crimper pivot motor 239 is transmitted to the crimper rotation shaft 340 via the output gear 239a and the drive transmission gear 340a, the crimper 32' rotates in the forward and reverse directions on the base 48 about the crimper rotation shaft 340 extending in the thickness direction of the sheet P placed on the internal tray 22. The guide rail 337, the crimper movement motor 238, the crimper pivot motor 239, the crimper rotation shaft 340, and the drive transmission assembly 240 constitute at least part of an example of a driving assembly of the crimper 32'.

[0153] The crimper 32' is movable between a standby position HP2 illustrated in FIG. 20A and a position where the crimper 32' faces a first binding position Bl illustrated in FIGS. 20B and 20C. The standby position HP2 is a position away in the main scanning direction from the sheet bundle Pb placed on the internal tray 22. The first binding position B 1 is a position on the sheet bundle Pb placed on the internal tray 22. However, the specific position of the first binding position Bl is not limited to the position illustrated in FIGS. 20B and 20C. The first binding position B 1 may be any one or more positions along the main scanning direction at the downstream end, in the conveyance direction, of the sheet P.

[0154] The posture of the crimper 32' changes or is pivoted between a parallel binding posture illustrated in 20B and an oblique binding posture illustrated in FIG. 20C. In other words, the crimper 32' is rotatable in the forward and reverse directions about the crimper rotation shaft 340. The parallel binding posture is a posture of the crimper 32' in which the length of the upper crimping teeth 32a and the lower crimping teeth 32b (i.e., a rectangular crimping trace) is along the main scanning direction. The oblique binding posture is a posture of the crimper 32' in which the length of the upper crimping teeth 32a and the lower crimping teeth 32b (i.e., the rectangular crimping trace) is inclined with respect to the main scanning direction.

[0155] The pivot angle (an angle of the upper crimping teeth 32a and the lower crimping teeth 32b with respect to the main scanning direction) in the inclined binding posture is not limited to the example of FIG. 20C, and may be any angle provided that the upper crimping teeth 32a and the lower crimping teeth 32b face the sheet bundle Pb placed on the internal tray 22.

[0156] The post-processing apparatus 3A includes the liquid applier 131 and a hole punch 132, which is an example of a processor. The liquid applier 131 and the hole punch 132 are disposed upstream from the internal tray 22 in the reverse conveyance direction. In addition, the liquid applier 131 and the hole punch 132 are disposed at different positions in the reverse conveyance direction to simultaneously face one sheet P that is conveyed by the conveyance roller pairs 10 to 19.

[0157] The liquid applier 131 and the hole punch 132 according to the present embodiment are disposed between the conveyance roller pairs 10 and 11. However, the arrangement of the liquid applier 131 is not limited to the example of FIG. 19. For example, in a case where an inserter 6 is disposed between the image forming apparatus 2 and the post-processing apparatus 3A as illustrated in FIG. 27, the liquid applier 131 may be disposed inside the inserter 6 located upstream from the post-processing apparatus 3A in a direction in which the sheet P is conveyed from the image forming apparatus 2 to the post-processing apparatus 3A. Examples of the inserter 6 include, but are not limited to, an apparatus that allows a preprinted medium, which is to be conveyed to the post-processing apparatus 3A together with the sheet P conveyed from the image forming apparatus 2, to be fed as a cover sheet, an insertion sheet, or a partition sheet without passing through the image forming apparatus 2.

[0158] As illustrated in FIG. 22A, the conveyance roller pair 11 is located so as not to overlap, in the main scanning direction, the first liquid application position B 1 on the sheet P to which the liquid is applied by a liquid application head 146 of the liquid applier 131. This arrangement is to prevent the amount of liquid at the first liquid application position B 1 from decreasing due to the multiple roller pairs pressing the first liquid application position Bl when the conveyance roller pair 11 conveys the sheet P. As a result, when the sheet P reaches the crimper 32' disposed downstream from the liquid applier 31 in the opposite conveyance direction, the amount of liquid at the first liquid application position B 1 is sufficient to maintain the binding strength. Accordingly, the binding strength of the sheet bundle Pb is prevented from decreasing due to a decrease in the amount of liquid at the first liquid application position B 1 (corresponding to the first binding position Bl) while the sheet P is conveyed.

[0159] In addition, the multiple roller pairs of the conveyance roller pair 11 that is located so as not to overlap the first liquid application position B 1 on the sheet P in the main scanning direction prevents the conveying performance of the sheet P from being worse due to the adhesion of liquid to the multiple roller pairs and further prevents a conveyance jam caused by the worsened conveying performance of the sheet P.

[0160] Although only the conveyance roller pair 11 has been described above, the multiple roller pairs of the conveyance roller pairs 14 and 15 are preferably located so as not to overlap the first liquid application position B 1 on the sheet P in the main scanning direction, like the multiple roller pairs of the conveyance roller pair 11.

[0161] The liquid applier 131 applies liquid to the sheet P that is conveyed by the conveyance roller pairs 10 and 11. In the following description, the application of liquid may be referred to as “liquid application.” The hole punch 132 punches a hole in the sheet P that is conveyed by the conveyance roller pairs 10 and 11 such that the hole penetrates the sheet P in the thickness direction of the sheet P. The processor disposed near the liquid applier 131 is not limited to the hole punch 132. Alternatively, the processor may be an inclination corrector that corrects an inclination or skew of the sheet P that is conveyed by the conveyance roller pairs 10 and 11.

[0162] FIGS. 22A and 22B are schematic views of the liquid applier 131 as viewed from the thickness direction of the sheet P, according to the third embodiment. FIGS. 23A, 23B, and 23C are cross-sectional views of the liquid applier 131 taken along line XXV -XXV of FIG. 22A. FIGS. 24A, 24B, and 24C are cross-sectional views of the liquid applier 131 taken along line XXVI-XXVI of FIG. 22A. As illustrated in FIGS. 22A to 24C, the liquid applier 131 includes a pair of guide shafts 133a and 133b, a pair of pulleys 134a and 134b, endless annular belts 135 and 136, a liquid- applier movement motor 137, a standby position sensor 138, and the liquid application unit 140.

[0163] The pair of guide shafts 133a and 133b each extend in the main scanning direction at positions spaced apart from each other in the reverse conveyance direction. The pair of guide shafts 133a and 133b are supported by a pair of side plates 4a and 4b of the post-processing apparatus 3A. The pair of guide shafts 133a and 133b support the liquid application unit 140 such that the liquid application unit 140 can move in the main scanning direction.

[0164] The pair of pulleys 134a and 134b is disposed between the guide shafts 133a and 133b in the reverse conveyance direction. On the other hand, the pulleys 134a and 134b are apart from each other in the main scanning direction. The pulleys 134a and 134b are supported by a frame of the post-processing apparatus 3A so as to be rotatable in the forward and reverse directions about the respective shafts extending in the thickness direction of the sheet P.

[0165] The endless annular belt 135 is looped around the pair of pulleys 134a and 134b. The endless annular belt 135 is coupled to the liquid application unit 140 by a connection 135a. The endless annular belt 136 is entrained around the pulley 134a and a driving pulley 137a that is fixed to an output shaft of the liquid- applier movement motor 137. The liquid-appliermovement motor 137 generates a driving force to move the liquid application unit 140 in the main scanning direction.

[0166] As the liquid-applier movement motor 137 rotates, the endless annular belt 136 circulates around the pulley 134a and the driving pulley 137a to rotate the pulley 134a. As the pulley 134a rotates, the endless annular belt 135 circulates around the pair of pulleys 134a and 134b. As a result, the liquid application unit 140 moves in the main scanning direction along the pair of guide shafts 133a and 133b. The liquid application unit 140 reciprocates in the main scanning direction in response to the rotation direction of the liquid-applier movement motor 137 being switched.

[0167] The standby position sensor 138 detects that the liquid application unit 140 has reached a standby position HP1 (see FIGS. 22A and 22B) in the main scanning direction. The standby position sensor 138 then outputs a standby position signal indicating the detection result to the controller 100b, which will be described below with reference to FIG. 25. The standby position sensor 138 is, for example, an optical sensor including a light emitter and a light receiver. The liquid application unit 140 at the standby position HP blocks an optical path between the light emitter and the light receiver. The standby position sensor 138 outputs the standby position signal in response to the light output from the light emitter not being received by the light receiver. The specific configuration of the standby position sensor 138 is not limited to the configuration described above.

[0168] As illustrated in FIGS. 23A, 23B, and 23C, the conveyance passage inside the post-processing apparatus 3A is defined by an upper guide plate 5a and a lower guide plate 5b, which are spaced apart from each other in the thickness direction of the sheet P. The liquid application unit 140 is located at a position to face an opening of the upper guide plate 5a. In other words, the liquid application unit 140 is disposed to face the conveyance passage (a position at which the liquid application unit 140 can face the sheet P) through the opening of the upper guide plate 5 a.

[0169] As illustrated in FIGS. 22A to 24C, the liquid application unit 140 includes a base 141, a rotary bracket 142, a liquid storage tank 143, a liquid-application-head mover 144, a holder 145, the liquid application head 146, columns 147a and 147b, a pressure plate 148, coil springs 149a and 149b, the application-head pivot motor 150, the application-head movement motor 151 (see FIG. 25), and a standby angle sensor 152 (see FIG. 25).

[0170] The base 141 is supported by the pair of guide shafts 133a and 133b so as to be slidable in the main scanning direction. The base 141 is coupled to the endless annular belt 135 by theconnection 135a. The base 141 supports the components 142 to 152 of the liquid application unit 140.

[0171] The rotary bracket 142 is attached to the lower face of the base 141 so as to be rotatable in the forward and reverse directions about a rotation shaft extending in the thickness direction of the sheet P. The rotary bracket 142 rotates with respect to the base 141 by a driving force transmitted from the application-head pivot motor 150. The rotary bracket 142 retains the liquid storage tank 143, the liquid-application-head mover 144, the holder 145, the liquid application head 146, the columns 147a and 147b, the pressure plate 148, and the coil springs 149a and 149b.

[0172] The standby angle sensor 152, which is also illustrated in FIG. 25, detects that the rotary bracket 142 has reached a standby angle. The standby angle sensor 152 then outputs a standby angle signal indicating the detection result to the controller 100b. The standby angle is, for example, an angle at the time of performing parallel binding. The standby angle sensor 152 is, for example, an optical sensor including a light emitter and a light receiver. The rotary bracket 142 at the standby angle blocks an optical path between the light emitter and the light receiver. The standby angle sensor 152 outputs the standby angle signal in response to the light output from the light emitter not being received by the light receiver. The specific configuration of the standby angle sensor 152 is not limited to the configuration described above.

[0173] FIG. 22A illustrates the rotary bracket 142 in a position for the parallel binding that is performed by the crimper 32' disposed downstream from the liquid applier 131 in a direction in which the sheet P is conveyed. FIG. 22B illustrates the rotary bracket 142 in a position for the oblique binding (i.e., corner binding) that is performed by the crimper 32' disposed downstream from the liquid applier 131 in the direction in which the sheet P is conveyed.

[0174] The liquid storage tank 143 stores liquid to be applied to the sheet P. The liquid-applicationhead mover 144 is attached to the liquid storage tank 143 so as to be movable (e.g., up and down) in the thickness direction of the sheet P. The liquid-application-head mover 144 moves with respect to the liquid storage tank 143 by a driving force transmitted from the application-head movement motor 151. The holder 145 is attached to a lower end of the liquid-application-head mover 144. The liquid application head 146 projects from the holder 145 toward the conveyance passage (downward in the present embodiment). The liquid that is stored in the liquid storage tank 143 is supplied to the liquid application head 146. The liquid application head 146 is made of a material having a high liquid absorption (e.g., sponge or fiber).

[0175] The columns 147a and 147b project downward from the holder 145 around the liquid application head 146. The columns 147a and 147b are movable with respect to the holder 145 relatively in the thickness direction. The columns 147a and 147b hold the pressure plate 148 at lower ends thereof. The pressure plate 148 has a through hole 148a at a position to face the liquid application head 146. The coil springs 149a and 149b are fitted around the columns 147a and 147b, respectively, between the holder 145 and the pressure plate 148. The coil springs 149a and 149b bias the columns 147a and 147b and the pressure plate 148 downward with respect to the holder 145.

[0176] As illustrated in FIGS. 23 A and 24A, before the sheet P is conveyed to the position where the sheet P faces the opening of the upper guide plate 5a, the pressure plate 148 is positioned at or above the opening. Subsequently, when the sheet P that is conveyed by the conveyance roller pairs 10 and 11 stops at a position where the first liquid application position B 1 on the sheet P faces the opening, the application-head movement motor 151 is rotated in a first direction. As a result, the liquid-application-head mover 144, the holder 145, the liquid application head 146, the columns 147a and 147b, the pressure plate 148, and the coil springs 149a and 149b move down together, and the pressure plate 148 contacts the sheet P. The first liquid application position B 1 corresponds to the position (i.e., the first binding position B 1) to be crimped and bound by the edge binder 251, specifically, the crimper 32'.

[0177] As the application-head movement motor 151 keeps rotating in the first direction even after the pressure plate 148 contacts the sheet P, the coil springs 149a and 149b are compressed to further move down the liquid-application-head mover 144, the holder 145, the liquid application head 146, and the columns 147a and 147b. As a result, as illustrated in FIGS. 23B and 24B, the lower face of the liquid application head 146 contacts the sheet P through the through hole 148a. As a result, the liquid contained in the liquid application head 146 is applied to the sheet P.

[0178] Further rotation of the application-head movement motor 151 in the first direction further strongly presses the liquid application head 146 against the sheet P as illustrated in FIGS. 23C and 24C. Accordingly, the amount of liquid applied to the sheet P increases. In short, the liquid applier 131 changes the pressing force of the liquid application head 146 against the sheet P to adjust the amount of liquid that is applied to the sheet P.

[0179] On the other hand, the rotation of the application-head movement motor 151 in the second direction opposite to the first direction moves up the liquid-application-head mover 144, the holder 145, the liquid application head 146, the columns 147a and 147b, the pressure plate 148, and the coil springs 149a and 149b together. As a result, as illustrated in FIGS. 23A and 24A, the liquid application head 146 and the pressure plate 148 are separated from the sheetP. In other words, the liquid applier 131 includes the liquid application head 146 that can be separated from the sheet P.

[0180] FIG. 25 is a diagram illustrating a hardware configuration of control blocks to control the operation of the post-processing apparatus 3A according to the third embodiment. As illustrated in FIG. 25, the post-processing apparatus 3A has a configuration in which a central processing unit (CPU) 101, a random-access memory (RAM) 102, a read-only memory (ROM) 103, a hard disk drive (HDD) 104, and an interface (I / F) 105 are connected via a common bus 109.

[0181] The CPU 101 is an arithmetic device and controls the overall operation of the post-processing apparatus 3A. The RAM 102 is a volatile storage medium that allows high speed reading and writing of data, and is used as a working area when the CPU 101 processes information. The ROM 103 is a read-only non-volatile storage medium, and stores programs such as firmware. The HDD 104 is a non-volatile storage medium that allows data to be read and written and has a relatively large storage capacity. The HDD 104 stores, for example, an operating system (OS), various control programs, and application programs.

[0182] The post-processing apparatus 3A processes, by an arithmetic function of the CPU 101, e.g., a control program stored in the ROM 103 and an information processing program (or application program) loaded into the RAM 102 from a storage medium such as the HDD 104. With such processing, a software controller including various functional modules of the postprocessing apparatus 3A is configured. The software controller thus configured is combined with hardware resources of the post-processing apparatus 3A mounted in the post-processing apparatus 3A to configure functional blocks that implement functions of the post-processing apparatus 3A. In other words, the CPU 101, the RAM 102, the ROM 103, the HDD 104, and the PF 105 constitute at least part of the controller 100b, which is an example of a control device, to control the operation of the post-processing apparatus 3A.

[0183] The PF 105 is an interface that connects the conveyance roller pairs 10, 11, 14, and 15, the switcher 20, the side fences 24L and 24R, the crimper movement motor 238, the crimper pivot motor 239, a contact- separation motor 32d, a liquid- applier movement motor 137, an application-head pivot motor 150, an application-head movement motor 151, a standby position sensor 138, a standby angle sensor 152, a hole punch 132, and an operation panel 110 to the common bus 109.

[0184] The controller 100b controls, via the PF 105, the operations of the conveyance roller pairs 10, 11, 14, and 15, the switcher 20, the side fences 24L and 24R, the crimper movement motor 238, the crimper pivot motor 239, the contact-separation motor 32d, the liquid-appliermovement motor 137, the application-head pivot motor 150, the application-head movement motor 151, and the hole punch 132. The controller 100b acquires detection results from the standby position sensor 138 and the standby angle sensor 152 through the VF 105.

[0185] Although FIG. 25 illustrates the components of the liquid applier 131 and the edge binder 251 (the crimper 32') that executes the edge binding, the components of the saddle binder 28 that executes the saddle binding are controlled by the controller 100b like the components of the liquid applier 131 and the edge binder 251 (the crimper 32') that executes the edge binding.

[0186] As illustrated in FIG. 27, the image forming apparatus 2 includes the operation panel 110. The operation panel 110 includes an operation section that receives instructions input by an operator and a display (which is an example of a notifier) that notifies the operator of information. The operation device includes, for example, hard keys and a touch screen overlaid on the display. The operation panel 110 acquires information from the user through the operation section and provides information to the user through the display. The postprocessing apparatus 3A may include an operation panel 110 similar to the above-described operation panel 110.

[0187] FIG. 26 is a flowchart of post-processing performed by the post-processing apparatus 3A according to the third embodiment. Specifically, FIG. 26 is a flowchart of a process to execute the one-point binding illustrated in FIGS. 20A to 20C.

[0188] For example, the controller 100b executes the post-processing illustrated in FIG. 26 in response to acquisition of an instruction (denoted below as “post-processing command”) of executing the post-processing from the image forming apparatus 2. The post-processing command includes, for example, the number of sheets P of the sheet bundle Pb (referred to as “given number of sheets Np”), the number of sheet bundles Pb to be subjected to binding processing, the first binding position B 1 (corresponding to the first liquid application position B 1), the angle of the first binding position B 1 (corresponding to the angle of the first liquid application position B l), the type of binding process (parallel binding process or oblique binding process), and an operation that is executed in parallel with the liquid application process (e.g., hole punching in the present embodiment). In the following description, the number of sheets P of the sheet bundle Pb may be referred to as a “given number of sheets Np,” and the number of sheet bundles Pb to be subjected to binding processing may be referred to as “requested number of copies Mp.” At the start of the post-processing, the liquid application unit 140 is at the standby position HP1 illustrated in FIGS. 22A and 22B, and the rotary bracket 142 is held at the standby angle (corresponding to the parallel binding posture) at the standby position HP1.

[0189] First, in step S801, the controller 100b drives the liquid-applier movement motor 137 to move the liquid application unit 140 (corresponding to a liquid applier) in the main scanning direction such that a liquid application head 146 moves from the standby position HP1 to a position where the liquid application head 146 can face the first liquid application position Bl (see FIG. 22B, the position corresponding to the binding position B 1 illustrated in FIGS. 20A to 20C). If the type of the binding process instructed by the post-processing command is "oblique binding process,” in step S801, the controller 100b drives the application-head pivot motor 150 to rotate the rotary bracket 142. Thus, the liquid application head 146 is rotated from the standby angle to the liquid application angle corresponding to the "oblique binding posture." It can be ascertained, based on pulse signals output from rotary encoders of the liquid-applier movement motor 137 and the application-head pivot motor 150, that the liquid application head 146 has reached the position where the liquid application head 146 can face the first liquid application position B l. If the type of the binding process instructed by the post-processing command is "parallel binding process", the controller 100b omits the abovedescribed operation of rotating the rotary bracket 142. In other words, the liquid application unit 140 moves in the main scanning direction while holding the rotary bracket 142 at the standby angle.

[0190] Further, in step S801, the controller 100b drives the crimper movement motor 238 to move the crimper 32' from the standby position HP2 to the position where the crimper 32' can face the first binding position B 1 as illustrated in FIGS. 20A and 20B. Alternatively, if the type of the binding process instructed by the post-processing command is "oblique binding process," in step S801, the controller 100b drives the crimper pivot motor 239 to rotate the crimper 32' from the standby angle to the crimping angle corresponding to the "oblique binding posture." It is ascertained based on a pulse signal output from a rotary encoder of the crimper movement motor 238 that the crimper 32' has reached the position where the crimper 32' can face the first binding position Bl. Similarly, it is ascertained based on a pulse signal output from a rotary encoder of the crimper pivot motor 239 that the crimper 32' has reached the crimping angle. If the type of the binding process instructed by the post-processing command is "parallel binding process," the controller 100b omits the above-described operation of rotating the crimper 32'. In other words, the crimper 32' moves in the main scanning direction while maintaining the standby angle.

[0191] In step S802, the controller 100b drives the conveyance roller pairs 10 and 11 to start conveying the sheet P on which an image is formed by the image forming apparatus 2. In step S8O3, the controller 100b determines whether the first liquid application position Bl on the sheet P faces first the liquid application unit 140 (more specifically, the liquid application head 146). In other words, the controller 100b determines whether the liquid application unit 140 has faced the first liquid application position B 1 on the sheet P. When the first liquidapplication position B 1 on the sheet P has not faced the liquid application unit 140 (NO in step S8O3), the controller 100b repeats the processing in step S8O3. In other words, the controller 100b continues driving the conveyance roller pairs 10 and 11 until the first liquid application position B 1 on the sheet P faces the liquid application head 146 (YES in step S8O3). When the controller 100b determines that the first liquid application position B 1 on the sheet P has faced the liquid application head 146 (YES in step S8O3), in step S804, the controller 100b causes the conveyance roller pairs 10 and 11 to stop conveying the sheet P. It is ascertained, based on a pulse signal output from a rotary encoder of a motor that drives the conveyance roller pairs 10 and 11, that the first liquid application position B 1 on the sheet P has faced the liquid application head 146.

[0192] In step S805, the controller 100b causes the liquid application unit 140 to execute the process of applying liquid to the first liquid application position B 1 on the sheet P. More specifically, the controller 100b rotates the application-head movement motor 151 in the first direction to bring the liquid application head 146 into contact with the first liquid application position B 1 on the sheet P. The controller 100b changes the pressing force of the liquid application head 146 (i.e., the amount of rotation of the application-head movement motor 151) depending on the amount of liquid to be applied to the sheet P.

[0193] The amount of liquid that is applied to the sheet P may be the same for all the sheets P of the sheet bundle Pb or may be different for each sheet P. For example, the controller 100b may decrease the amount of liquid applied to a sheet P conveyed later. The amount of rotation of the application-head movement motor 151 can be ascertained based on a pulse signal output from a rotary encoder of the application-head movement motor 151.

[0194] In step S806, the controller 100b drives the conveyance roller pairs 10, 11, 14, and 15 to place a sheet P on the internal tray 22. In step S806, the controller 100b also moves the side fences 24L and 24R to align the position of the sheet P or the sheet bundle Pb placed on the internal tray 22 in the main scanning direction in step S806. In short, the controller 100b performs so- called jogging.

[0195] In step S807, the controller 100b determines whether the number of sheets P placed on the internal tray 22 has reached the given number of sheets Np indicated by the post-processing command. When the controller 100b determines that the number of sheets P placed on the internal tray 22 has not reached the given number of sheets Np (NO in step S807), the controller 100b executes the operations of steps S802 to S807 again until the number of sheets P placed on the internal tray 22 reaches the given number of sheets Np (YES in step S807).

[0196] By contrast, when the controller 100b determines that the number of sheets P that are placed on the internal tray 22 has reached the given number of sheets Np (YES in step S807), in step S8O8, the controller 100b causes the crimper 32' to crimp the first binding position Bl (corresponding to the first liquid application position B 1 of the sheet P) on the sheet bundle Pb including the sheet P to which the liquid has been applied by the liquid application unit 140. In addition, in step S8O8, the controller 100b rotates the conveyance roller pair 15 to eject the crimped sheet bundle Pb to the ejection tray 26.

[0197] In step S809, the controller 100b determines whether the number of sheet bundles Pb thus ejected to the ejection tray 26 has reached the requested number of copies Mp indicated by the binding command. When the controller 100b determines that the number of the sheet bundles Pb ejected to the ejection tray 26 has not reached the requested number of copies Mp (NO in step S809), the controller 100b repeats the processing of steps S802 to S809 until the number of the sheet bundles Pb ejected to the ejection tray 26 reaches the requested number of copies Mp (YES in step S809).

[0198] When the controller 100b determines that the number of sheet bundles Pb ejected to the ejection tray 26 reaches the requested number of copies Mp (YES in step S809), in step S810, the controller 100b drives the liquid- applier movement motor 137 to move the liquid application unit 140 to the standby position HP1 (see FIGS. 22B) and drives the crimper movement motor 238 to move the crimper 32' to the standby position HP2 (see FIG. 20A). When the posture that is instructed by the post-processing operation is the “oblique binding posture,” in step S810, the controller 100b drives the application-head pivot motor 150 and the crimper pivot motor 239 to rotate the liquid application unit 140 and crimper 32' and the parallel binding posture (standby angle) into the parallel binding posture. By contrast, when the posture that is instructed by the post-processing command is the “parallel binding posture,” the controller 100b skips the aforementioned operation of rotating the liquid application unit 140 and the crimper 32' to the parallel binding posture (standby angle). In steps S801 and S810, the execution order of the movement in the main scanning direction and the rotation in the forward and reverse directions of the liquid application unit 140 and the crimper 32' is not limited to the aforementioned order and may be reversed.

[0199] The present disclosure can be applied to not only the edge binder 251 that executes edge binding but also to the saddle binder 28 that executes saddle stitching.

[0200] The controller 100b of the post-processing apparatus 3A according to the third embodiment illustrated in FIGS. 29A and 29B is provided separately from the controller 100a of the image forming apparatus 2 as in the configuration of FIG. 1. However, embodiments of the present disclosure are not limited to the above-described configuration. For example, as illustrated inFIG. 28A, the controller 100b of the post-processing apparatus 3A may be disposed in the image forming apparatus 2. Further, as in the configuration of FIG. 28B, the controller 100b of the post-processing apparatus 3 A may be integrated with the controller 100a of the image forming apparatus 2.

[0201] As in the configuration of FIG. 29A, the controller 100b of the post-processing apparatus 3A may be divided into a controller 100b 1 (e.g., a driver system such as a motor) and a controller 100b2 (a detector such as a sensor) according to the function, and the controller 100b2 of the post-processing apparatus 3A may be disposed in the image forming apparatus 2. Further, as in the configuration of FIG. 29B, the controller 100b2 of the post-processing apparatus 3 A disposed in the image forming apparatus 2 may be integrated with the controller 100a of the image forming apparatus 2.

[0202] As described above, the control method by the controller 100b described above is implemented by cooperation between hardware resources of a computer and a program as computer software. In other words, the control method may be a method executed by a computer causing an arithmetic device, a storage device, an input device, an output device, and a control device to operate in cooperation with each other based on a program. The program may be written in, for example, a storage device or a storage medium and distributed with the storage device or the storage medium, or may be distributed through, for example, an electric communication line.

[0203] The present disclosure is not limited to the above-described embodiments, and numerous additional modifications and variations are possible in light of the teachings within the technical scope of the appended claims. The above-described embodiments and modifications are some examples, and various modifications and variations can be practiced from such examples by those skilled in the art. Such modifications are included in the technical scope described in the scope of claims.

[0204] Any one of the above-described operations may be performed in various other ways, for example, in an order different from the one described above.

[0205] The functionality of the elements disclosed herein may be implemented using circuitry or processing circuitry which includes general purpose processors, special purpose processors, integrated circuits, application- specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), and / or combinations thereof which are configured or programmed, using one or more programs stored in one or more memories, to perform the disclosed functionality. Processors are considered processing circuitry or circuitry as they include transistors and other circuitry therein. In the disclosure, the circuitry, units, or means are hardware that carryout or are programmed to perform the recited functionality. The hardware may be any hardware disclosed herein which is programmed or configured to carry out the recited functionality.

[0206] There is a memory that stores a computer program which includes computer instructions. These computer instructions provide the logic and routines that enable the hardware (e.g., processing circuitry or circuitry) to perform the method disclosed herein. This computer program can be implemented in known formats as a computer-readable storage medium, a computer program product, a memory device, a record medium such as a CD-ROM or DVD, and / or the memory of an FPGA or ASIC.

[0207] As described above, the medium processing apparatus according to at least one embodiment of the present disclosure, the number of repetitions of the binding process on a sheet bundle Pb can be changed according to the type of post-processing to set an appropriate binding force (binding strength) and an appropriate binding process speed (productivity) according to the binding process. Such a configuration can increase the convenience of the user and the productivity of the binding process.

[0208] Aspects of the present disclosure are, for example, as follows.First aspectA medium processing apparatus includes a crimper to press and deform a medium bundle including a plurality of media, with a pair of binding teeth, to bind the medium bundle and a controller to control an operation of the crimper. The controller switches whether to execute a pressing-hold control of holding a state in which the medium bundle is pressed and deformed with the pair of binding teeth.Second aspectIn the medium processing apparatus according to the first aspect, the controller switches whether to execute the pressing-hold control based on medium information of the medium bundle.Third aspectIn the medium processing device according to the second aspect, the medium information includes at least one of the number of media included in the medium bundle, a thickness of the medium, and a type of the medium.Fourth aspectThe medium processing apparatus according to any one of the first to third aspects further including an operation device to receive an operation of a user. The controller switches whether to execute the pressing-hold control according to the operation of the user received by the operation device.Fifth aspectThe medium processing apparatus according to any one of the first to third aspects further includes an operation device to receive an operation of a user. The controller executes the pressing-hold control in a case in which the number of media included in the medium bundle is equal to or greater than a threshold number of media received by the operation device from the user.Sixth aspectIn the medium processing apparatus according to any one of the first to fifth aspects, the controller holds a state in which the pair of binding teeth are closest to each other for a predetermined time in the pressing-hold control.Seventh aspectIn the medium processing apparatus according to any one of the first to sixth aspects, the controller changes an execution time of the pressing-hold control.Eighth aspectThe medium processing apparatus according to any one of the first to seventh aspects further includes a contact- separation motor and a contact- separation assembly to move the pair of binding teeth close to or away from each other in a process in which an eccentric cam rotated by a driving force of the contact- separation motor rotates one turn. In a case in which the pressing-hold control is executed, the controller temporarily stops the contact-separation motor at a timing at which the eccentric cam rotates to reach a predetermined rotation angle, and restarts rotation of the contact- separation motor when a holding time elapses. In a case in which the pressing-hold control is not executed, the controller continues rotation of the contact- separation motor until the eccentric cam rotates one turn.Ninth aspectAn image forming system includes an image forming apparatus to form images on media constituting the plurality of media, and the medium processing apparatus according to any one of the first to eighth aspects to press and deform the plurality of media, on which the images are formed by the image forming apparatus, to bind the plurality of media.

[0209] This patent application is based on and claims priority to Japanese Patent Application No. 2024-087496, filed on May 29, 2024, in the Japan Patent Office, the entire disclosure of which is hereby incorporated by reference herein.[Reference Signs]

[0210] 1: Image forming system2: Image forming apparatus3: Post-processing apparatus10 to 19: Conveyance Roller Pairs20: Switcher21: Ejection tray: Internal tray : End fence L and 24R: Side fences : Edge binder : Ejection tray : End fence : Saddle binder : Sheet folding blade : Ejection tray : Liquid applier : Crimper a: Upper crimping teeth b: Lower crimping teeth : Lower pressure plate : Upper pressure plate a: Through hole : Liquid- applier movement assembly: Liquid application assembly : Liquid- applier movement motor : Trapezoidal screw : Nut : Base plate a and 41b: Columns a and 42b: Coil springs : First liquid storage tank a: Liquid-level sensor : Liquid application member : Liquid supplier a: Protector : Joint : Edge-binder movement assembly : Base : Guide shaft : Edge-binder movement motor 1: Driving force transmission assembly: Staple binder : Stapler a: Stapling part : Staple-binder movement assembly: Base : Staple-binder movement motor : Driving force transmission assembly: Contact- separation assembly : Upper arm : Lower arm : Coil spring : Drive gear : Driven gear : Eccentric cam : Rotation shaft : Home position sensor : Encoder sensor 0a and 100b: Controllers 1: CPU 2: RAM 3: ROM 4: HDD 5: I / F 9: Common bus 0: Operation panel

Claims

[CLAIMS]

1. A medium processing apparatus, comprising: a crimper to press and deform a medium bundle including a plurality of media, with a pair of binding teeth, to bind the medium bundle; and a controller to control an operation of the crimper, wherein the controller switches whether to execute a pressing-hold control of holding a state in which the medium bundle is pressed and deformed with the pair of binding teeth.

2. The medium processing apparatus according to claim 1, wherein the controller switches whether to execute the pressing-hold control based on medium information of the medium bundle.

3. The medium processing apparatus according to claim 2, wherein the medium information includes at least one of a number of media included in the medium bundle, a thickness of a medium, and a type of the medium.

4. The medium processing apparatus according to any one of claims 1 to 3, further comprising an operation device to receive an operation of a user, wherein the controller switches whether to execute the pressing-hold control according to the operation of the user received by the operation device.

5. The medium processing apparatus according to any one of claims 1 to 3, further comprising an operation device to receive an operation of a user, wherein the controller executes the pressing-hold control in a case in which a number of media included in the medium bundle is equal to or greater than a threshold number of media received by the operation device from the user.

6. The medium processing apparatus according to any one of claims 1 to 5, wherein the controller holds a state in which the pair of binding teeth are closest to each other for a predetermined time in the pressing-hold control.

7. The medium processing apparatus according to any one of claims 1 to 6, wherein the controller changes an execution time of the pressing-hold control.

8. The medium processing apparatus according to any one of claims 1 to 7, further comprising a contact- separation motor and a contact-separation assembly to move the pair of binding teeth close to or away from each other in a process in which an eccentric cam rotated by a driving force of the contact- separation motor rotates one turn,wherein, in a case in which the pressing-hold control is executed, the controller temporarily stops the contact- separation motor at a timing at which the eccentric cam rotates to reach a predetermined rotation angle, and restarts rotation of the contact-separation motor when a holding time elapses, and in a case in which the pressing-hold control is not executed, the controller continues rotation of the contact-separation motor until the eccentric cam rotates one turn.

9. An image forming system, comprising: an image forming apparatus to form an image on media constituting the medium bundle; and the medium processing apparatus according to any one of claims 1 to 8 to press and deform the medium bundle, on which the image is formed by the image forming apparatus, to bind the medium bundle.

Images