Folding device and image forming device

Abstract

To provide a folding processing device that can improve precision to a folding position of a recording medium, more in comparison with a folding processing device configured so that a conveying roll pair arranged at a downstream side in a conveying direction with respect to a folding part is always in a nip state, and an image forming device.SOLUTION: The folding processing device comprises: a folding part that folds a recording medium at a middle part in a conveying direction of the recording medium; an upstream-side roll pair, arranged at an upstream side in the conveying direction of the recording medium with respect to the folding part, which conveys the recording medium in a folded state to the folding part side; and a downstream-side roll pair, arranged at a downstream side in the conveying direction of the recording medium with respect to the folding part, which conveys the recording medium in the folded state along the conveying direction; and a conveying roll pair, arranged at the opposite side of the folding part side with respect to the downstream-side roll pair, which can be switched between a nip state and a nip-released state, which brings the conveying roll pair into the nip-released state when making the folding part fold the recording medium.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a folding device and an image forming device. [Background technology]

[0002] Patent Document 1 describes a creasing device that creases sheets one by one using a creasing device provided before a folding mechanism that performs folding processing. This creasing device includes a detection device that detects the position of the sheet, gripping devices that are arranged upstream and downstream of the creasing device in the sheet transport direction and grip the sheet, and a sag correction device that applies tension to the sheet between the gripping devices to correct any sag, and is characterized in that the sag is corrected by the sag correction device before the creasing device creases the sheet. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5471211 Summary of the Invention [Problem to be solved by the invention]

[0004] The object of the present invention is to provide a folding processing device and an image forming device that can improve the accuracy of the folding position of a recording medium compared to a configuration in which a pair of transport rolls arranged downstream in the transport direction relative to the folding section are always in a nipped state. [Means for solving the problem]

[0005] In order to achieve the above object, a first aspect of the folding processing device comprises a folding unit that folds a recording medium at a middle portion in the transport direction of the recording medium, an upstream roll pair that is arranged upstream of the folding unit in the transport direction of the recording medium and transports the folded recording medium toward the folding unit, a downstream roll pair that is arranged downstream of the folding unit in the transport direction of the recording medium and transports the folded recording medium along the transport direction, and a transport roll pair that is arranged on the opposite side of the folding unit from the downstream roll pair and can be switched between a nip state and a nip elimination state, and when folding the recording medium at the folding unit, the transport roll pair is put into the nip elimination state.

[0006] The second aspect of the folding processing device is the folding processing device of the first aspect, wherein the pair of transport rolls constitutes a transport path for transporting the recording medium to another processing section, and the pair of transport rolls are nipped when transporting the folded recording medium to the other processing section.

[0007] A folding processing device of a third aspect is the folding processing device of the second aspect, wherein the folding units are plural, and the transport roll pair transports the recording medium folded at the final folding unit to the other processing unit.

[0008] A fourth aspect of the folding processing device is the folding processing device of the second aspect, in which the folding section is multiple, and the transport roll pair transports the recording medium folded at the first folding section and the final folding section to the other processing section.

[0009] A fifth aspect of the folding processing device is a folding processing device of any one of the first to fourth aspects, in which the conveying roll pairs are arranged in a plurality of pairs along the conveying direction, and a conveying roll pair to be put into a nip-eliminating state is selected from the plurality of conveying roll pairs depending on the size of the recording medium and the folding state of the recording medium.

[0010] The image forming apparatus of the sixth aspect includes a forming unit that forms an image on a recording medium, and a folding processing device according to any one of claims 1 to 5 that folds the recording medium on which the image has been formed in the forming unit in the folding unit. [Effects of the Invention]

[0011] According to the folding device of the first aspect, the accuracy of the folding position of the recording medium is improved compared to a configuration in which the pair of transport rolls arranged downstream in the transport direction from the folding unit are always in a nipped state.

[0012] According to the folding device of the second aspect, the folding device can be made smaller than a configuration in which a dedicated space is provided for releasing the recording medium when the recording medium is folded.

[0013] According to the third aspect of the folding processing device, the accuracy of the final folding position of the recording medium can be improved compared to a configuration in which a pair of transport rolls arranged downstream in the transport direction relative to the folding section are always in a nipped state.

[0014] According to the fourth aspect of the folding processing device, in a configuration in which the recording medium folded from the first fold and the final fold is transported to another processing section by a common pair of transport rolls, the accuracy of the initial folding position of the recording medium can be improved compared to a configuration in which the pair of transport rolls arranged downstream in the transport direction from the folding section is always in a nipped state.

[0015] According to the fifth aspect of the folding processing device, when folding a recording medium at the folding section, power consumption is reduced compared to when all transport roll pairs arranged downstream of the folding section in the transport direction are in a nip-disengagement state.

[0016] According to the image forming apparatus of the sixth aspect, the accuracy of the folding position of the recording medium is improved compared to a configuration in which the pair of transport rolls arranged downstream in the transport direction from the folding portion are always in a nip state. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a front cross-sectional view showing an example of an image forming apparatus including a folding device according to an embodiment of the present invention; [Figure 2]2 is a front cross-sectional view showing the main body side of the image forming apparatus of FIG. 1. [Figure 3] FIG. 2 is a front cross-sectional view showing the folding device side of FIG. [Figure 4] FIG. 2 is an enlarged view showing a folding unit of the folding device according to the embodiment. [Figure 5] 4 is an enlarged view showing a main part in order to explain the operation of a first folding unit of the folding device according to the embodiment. FIG. [Figure 6] 1 is an enlarged view showing the main parts to explain the action of a pair of transport rolls provided at the leading edge of the recording medium when folding the recording medium in the second folding section as the folding section of the folding processing device according to this embodiment. FIG. [Figure 7] 10 is an enlarged view showing a main part for explaining the operation of a third folding unit as a folding unit of the folding device according to the embodiment. FIG. [Figure 8] 10 is an enlarged view showing a main part of the folding processing device according to the embodiment in order to explain the operation of a conveying unit that conveys the folding processing device to the outside. FIG. [Figure 9] 1A is a diagram showing accordion folding of a recording medium, and FIG. 1B is a diagram showing gatefold folding of a recording medium. [Figure 10] (A) is a diagram showing a Z-fold of a recording medium, (B) is a diagram showing an inward three-fold of a recording medium, (C) is a diagram showing an outward three-fold of a recording medium, and (D) is a diagram showing a quarter-fold of a recording medium. [Figure 11] 7 is an enlarged view corresponding to FIG. 6 showing a main part in an enlarged manner to explain the operation of a transport roll pair as a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings.

[0019] First Embodiment FIG. 1 shows an example of an image forming apparatus 10 equipped with a folding device 14 according to the first embodiment, and is a front cross-sectional view of the image forming apparatus 10 as seen from the front side.

[0020] As shown in FIG. 1, the image forming apparatus 10 according to this embodiment includes an image forming apparatus main body (forming unit) 12 that forms an image on a sheet material P as a recording medium, and a folding processing device 14 that creases the sheet material P (folds the sheet material P).

[0021] In this embodiment, the width direction (horizontal direction) of the device is defined as the X direction, the up-down direction (vertical direction) of the device is defined as the Y direction, and the depth direction (horizontal direction) of the device is defined as the Z direction. In this embodiment, the X direction, Y direction, and Z direction are perpendicular to each other.

[0022] FIG. 2 shows an example of the image forming apparatus main body 12, and is a front cross-sectional view of the image forming apparatus main body 12 as seen from the front side.

[0023] As shown in FIG. 2, the image forming apparatus main body 12 according to this embodiment is provided with a supply unit 16, a conveying unit 18, an image forming unit 20, and an image reading unit 22, in this order. The supply unit 16 supplies the sheet material P from the bottom to the top in the Y direction. The conveying unit 18 conveys the sheet material P supplied by the supply unit 16. The image forming unit 20 forms a toner image on the sheet material P conveyed by the conveying unit 18. The image reading unit 22 reads an image of the original G. The image reading unit 22 is an example of a reading unit. The image forming apparatus 10 is further provided with a fixing unit 24 that applies heat and pressure to the sheet material P on which the toner image has been formed, to fix the toner image to the recording medium.

[0024] The supply unit 16 is provided with a plurality of storage members 26 that can be pulled out from the image forming apparatus main body 12 toward the front in the Z direction, and sheet materials P are stacked in each of these storage members 26. Furthermore, each storage member 26 is provided with a feed roll 30 that sends out the sheet materials P stacked in the storage member 26 to a transport path 28 that constitutes the transport unit 18. The transport unit 18 is provided with a plurality of transport roll pairs 32 that transport the sheet materials P along the transport path 28.

[0025] The image reading section 22 is provided with a platen glass 34 on which an original G is placed, and a reading unit 36 ​​that reads the image of the original G placed on the platen glass 34. The reading unit 36 ​​is provided with a CCD (Charge Coupled Device) 36A, a lens 36B, and a lamp 36C. Light irradiated onto the original G from the lamp 36C is reflected and received by the CCD 36A via the lens 36B. In this way, the image of the original G is read, and image data is obtained.

[0026] The image forming section 20 is provided with four image forming units 38Y, 38M, 38C, and 38K for yellow (Y), magenta (M), cyan (C), and black (K). In the following description, when there is no need to distinguish between Y, M, C, and K, the terms Y, M, C, and K may be omitted. The image forming section 20 is also provided with an exposure device 42 for each color that irradiates exposure light onto an image carrier 40 (only image carrier 40Y is shown) provided in the image forming unit 38 based on image data read by the reading unit 36.

[0027] The image forming units 38 for each color are detachably attached to the image forming apparatus main body 12. Each image forming unit 38 for each color includes an image carrier 40 and a charging member 44 (only charging member 44Y is shown) that charges the surface of the image carrier 40. Furthermore, each image forming unit 38 for each color includes a developing device 46 (only developing device 46Y is shown) that develops an electrostatic latent image formed by irradiating the charged image carrier 40 with exposure light by the exposure device 42, and visualizes it as a toner image.

[0028] The image forming unit 20 is also provided with an endless transfer belt 48 that rotates in the direction of arrow A in the figure, and primary transfer rolls 50 (only the primary transfer roll 50Y is shown) that transfer the toner images formed by the image forming units 38 of each color onto the transfer belt 48. The image forming unit 20 is also provided with a secondary transfer roll 52 that transfers the toner images transferred onto the transfer belt 48 onto the sheet member P.

[0029] In the image forming apparatus 10 according to this embodiment, an image is formed as follows.

[0030] First, the charging members 44 of each color (only the charging member 44Y is shown) to which a voltage is applied uniformly negatively charge the surface of the image carrier 40 of each color at a predetermined potential. Next, based on the image data read by the reading unit 36, the exposure device 42 irradiates the charged surface of the image carrier 40 of each color with exposure light to form an electrostatic latent image.

[0031] As a result, an electrostatic latent image corresponding to the image data is formed on the surface of the image carrier 40 of each color. The developing device 46 of each color then develops this electrostatic latent image, making it visible as a toner image. The toner image formed on the surface of the image carrier 40 of each color is then transferred to the transfer belt 48 by the primary transfer roll 50.

[0032] Therefore, the sheet material P sent out from the storage member 26 to the conveying path 28 by the delivery roll 30 is sent to a transfer position T where the transfer belt 48 comes into contact with the secondary transfer roll 52. At the transfer position T, the sheet material P is conveyed between the transfer belt 48 and the secondary transfer roll 52, so that the toner image on the surface of the transfer belt 48 is transferred to the sheet material P.

[0033] The toner image transferred to the sheet member P is fixed to the sheet member P by the fixing unit 24. The fixing unit 24 is disposed downstream of the secondary transfer roll 52 in the conveyance direction of the sheet member P, and includes a heating roll 54 that is rotationally driven by a torque transmitted from a stepping motor (not shown). A halogen heater 54A is disposed inside the heating roll 54.

[0034] The fixing unit 24 also includes a pressure roll 56 that presses the conveyed sheet material P toward the heating roll 54 and is rotatably supported, and by sandwiching and conveying the sheet material P with the toner image transferred thereon between the heating roll 54 and the pressure roll 56, the sheet material P is heated and pressurized to fix the toner image to the sheet material P. Then, the sheet material P with the fixed toner image is discharged to the outside of the image forming apparatus main body 12 through a discharge port 57.

[0035] (folding device) Next, the folding device 14 according to this embodiment will be described.

[0036] 3 is a front cross-sectional view of the folding device 14 as seen from the front side. As shown in FIGS. 1 and 3, the folding device 14 is provided with an entrance section 15 connected to a discharge outlet 57 provided in the image forming apparatus main body 12. The folding device 14 is provided with a conveying section 60 that conveys the sheet material P discharged from the image forming apparatus main body 12 through the entrance section 15, and a folding section 62 that performs a folding process on the sheet material P conveyed by the conveying section 60 (folds the sheet material P).

[0037] The conveying section 60 includes a plurality of conveying roll pairs 66 that convey the sheet material P along a conveying path 59 along which the sheet material P is conveyed. A plurality of sensors 67 are provided in the conveying path 59 to detect the leading and trailing ends of the conveyed sheet material P. The detection of the sheet material P by the sensors 67 adjusts the drive timing of roll pairs including a folding roll pair 74 (described later) and the like.

[0038] In addition, the conveying path 59 is configured to include a conveying path 61 (conveying path 63) for discharging the sheet material P to the outside of the folding processing device 14 without performing a folding process on the sheet material P, and a conveying path 64 (conveying path 65) for performing a folding process on the sheet material P.

[0039] The conveying path 63 is a path for conveying the sheet material P discharged from the image forming apparatus main body 12 in the X direction (horizontal direction). The conveying path 65 is a path for folding the sheet material P discharged from the image forming apparatus main body 12 and conveying the sheet material P, and the conveying path 65 includes a plurality of conveying paths 65A, 65B, 65C, etc. corresponding to the folding specifications of the sheet material P (described later).

[0040] 4 to 8 are enlarged views showing the folding section 62. As shown in Fig. 4, the folding section 62 is provided in the conveying path 64, and the folding section 62 is configured to include a first folding section (initial folding section) 68, a second folding section (folding section) 70, and a third folding section (final folding section) 72.

[0041] As shown in FIG. 5, the first folding section 68 includes a pair of roll-shaped folding rolls 74 and a pushing member 76.

[0042] The folding roll pair 74 is composed of a folding roll 74A and a folding roll 74B, and the folding rolls 74A and 74B are arranged along the conveying direction of the sheet material P with their longitudinal direction being a direction that intersects (orthogonal, the same applies below) the conveying direction of the sheet material P, and apply a conveying force to the sheet material P.

[0043] On the other hand, the pushing member 76 is disposed on the opposite side of the pair of folding rolls 74 across the conveying path 64, and is provided with its longitudinal direction intersecting the conveying direction of the sheet material P. In addition, the pushing member 76 has a tip 76A formed to be sharp, so that a part of the sheet material P being conveyed (the position to be folded) can be pushed between the folding rolls 74A and 74B.

[0044] A portion of the sheet material P is pushed between the folding rolls 74A and 74B via the pushing member 76, causing the sheet material P to be folded starting from that portion of the sheet material P, and when the sheet material P passes between the folding rolls 74A and 74B, a crease Q1 (see Figure 6) is made in the sheet material P.

[0045] A conveying path 64A is provided between the folding rolls 74A and 74B in a direction intersecting the conveying path 64. The path along which the sheet material P is conveyed by the conveying path 64A branched off from the conveying path 64 is conveying path 65A, and the sheet material P folded once by the pair of folding rolls 74 of the first folding unit 68 is conveyed.

[0046] Here, an upstream roll pair 78 is provided upstream of the first folding unit 68 in the conveying direction of the sheet material P. The upstream roll pair 78 is composed of an upstream roll 78A and an upstream roll 78B, and the upstream rolls 78A, 78B are provided with their longitudinal directions intersecting the conveying direction of the sheet material P. The upstream roll 78A and the upstream roll 78B are arranged with the conveying path 64 between them, and the upstream roll 78A and the upstream roll 78B hold the sheet material P between them and apply a conveying force to the sheet material P.

[0047] 3, a guide 80 is provided downstream of the first folding unit 68 in the conveyance direction of the sheet material P, and the guide 80 is provided along the substantially vertical direction of the folding device 14. Strictly speaking, the guide 80 is inclined downward from the folding device 14 as it approaches the image forming apparatus main body 12.

[0048] Furthermore, an abutment portion 80A is provided at the tip of the guide 80. The abutment portion 80A is formed along a direction intersecting the conveying direction of the sheet material P, and stands upright relative to a conveying surface 80B of the guide 80. Therefore, when the sheet material P is conveyed to the guide 80, the sheet material P abuts against the abutment portion 80A of the guide 80, and its movement is restricted.

[0049] The guide 80 is extendable and retractable along the conveying direction of the sheet material P. For example, the guide 80 includes a slide member that slides along the conveying direction of the sheet material P relative to the main body, and an abutting portion 80A is formed at the tip of the slide member, and the position of the abutting portion 80A is adjusted according to the folding position of the sheet material P and the size of the sheet material P.

[0050] 6, a conveying path 64A along which the sheet material P folded once by the folding roll pair 74 of the first folding unit 68 is conveyed is provided with a conveying roll pair 66. Here, one conveying roll pair 66 is provided, but multiple conveying roll pairs 66 may be provided. The conveying roll pair 66 is made up of a conveying roll 66A and a conveying roll 66B, and in the conveying path 64A, the conveying roll 66A can be moved toward and away from the conveying roll 66B. In other words, the conveying roll pair 66 constituting the conveying path 64A can be switched between a nip state in which the sheet material P is nipped, and a nip release state in which the nipped state is released.

[0051] As for the mechanism for moving the conveying roll 66A toward and away from the conveying roll 66B, well-known technology is applied, for example, a cam is in contact with a bearing that rotatably supports the conveying roll 66A, and by rotating the cam, the conveying roll 66A is moved toward and away from the conveying roll 66B.

[0052] 3 and is configured by a plurality of pairs of conveying rolls 71, which conveys the sheet material P to discharge ports 75 and 77, which will be described later. Therefore, for example, when the sheet material P is folded only once, such as in half, the sheet material P is conveyed to the outside of the folding device 14 (to another processing unit) by the conveying path 64A and the conveying path 73.

[0053] In this embodiment, as shown in Fig. 3, the folding device 14 is provided with two discharge openings 75, 77. The discharge opening 75 is provided in the conveying path 65, and is formed on the top surface 14A side of the folding device 14. On the other hand, the discharge opening 77 is provided in the conveying paths 63, 65, and is formed on the right side surface 14B of the folding device 14 in the figure. Discharge trays 79, 81 are provided at the discharge openings 75, 77, respectively, and the folded sheet material P is discharged onto the discharge trays 79, 81, respectively.

[0054] In this embodiment, as shown in FIG. 1, the image forming apparatus 10 is configured with an image forming apparatus main body 12 that forms an image on a sheet material P and a folding device 14 that folds the sheet material P. However, a post-processing device that performs bookbinding, such as binding, may also be provided as another processing device. In this case, the discharge port 77 discharges the sheet material P to the post-processing device. That is, in a configuration without a binding device, the discharge process to the discharge unit may be considered as another processing device. Furthermore, if an edge alignment device such as a tamper is provided in the discharge unit, the edge alignment device may be considered as another processing device.

[0055] In this embodiment, as shown in FIG. 3, the sheet material P transported via the transport path 65 (65A, 65B, 65C) is discharged at the discharge outlet 75 or the discharge outlet 77 by the transport path 73 provided downstream in the transport direction of the sheet material P relative to the transport path 64 (64A, 64B, 64C).

[0056] The conveying path 73 includes a conveying path 73A where the conveying paths 64 (64A, 64B, 64C) constituting the conveying route 65 converge. This conveying path 73A is provided with a branching portion 83 on the downstream side in the conveying direction of the sheet material P. In addition, the conveying path 73A is provided with a conveying path 73A1 connecting the branching portion 83 and the discharge outlet 75 and a conveying path 73A2 connecting the branching portion 83 and the discharge outlet 77, and the conveying path 73A is branched by the branching portion 83 into the conveying path 73A1 or the conveying path 73A2.

[0057] As described above, the transport path 73 is configured with a plurality of transport roll pairs 71. Here, three transport roll pairs 71 are provided, but the number of transport roll pairs 71 is not limited to three. Also, as shown in FIG. 4, the transport roll pair 71 is configured with a transport roll 71A and a transport roll 71B, and in the transport path 73A, the transport roll 71A can be moved toward and away from the transport roll 71B by a mechanism similar to that of the transport roll pair 66 that configures the transport path 64A. Therefore, the transport roll pair 71 can be switched between a so-called nip state and a nip-release state with respect to the sheet member P.

[0058] As shown in FIG. 6, the second folding section 70, like the first folding section 68, is configured to include a pair of roll-shaped folding rolls 82 and a pushing member 84.

[0059] The folding roll pair 82 is composed of a folding roll 82A and a folding roll 82B, and the folding rolls 82A and 82B are arranged along the conveying direction of the sheet material P, with their longitudinal direction being a direction intersecting the conveying direction of the sheet material P, and apply a conveying force to the sheet material P.

[0060] On the other hand, pushing member 84 is disposed on the opposite side of folding roll pair 82 with conveying path 64A in between, and is provided with its longitudinal direction intersecting the conveying direction of sheet material P. Pushing member 84 has tip 76A formed to be sharp, and is capable of moving toward and away from conveying path 64A, and is capable of pushing another portion (position to be folded) of sheet material P being conveyed between folding roll 82A and folding roll 82B.

[0061] A portion of the sheet material P is pushed between the folding rolls 82A and 82B via the pushing member 84, and the sheet material P that has been folded once is folded starting from another portion of the sheet material P, and when it passes between the folding rolls 82A and 82B, a crease is formed in the sheet material P.

[0062] A conveying path 64B is provided between the folding rolls 82A and 82B in a direction intersecting with the conveying path 64A. The conveying path 64B branches off from the conveying path 64A to convey the sheet material P, which is conveyed as a conveying path 65B, and the sheet material P folded twice by the pair of folding rolls 74 of the first folding unit 68 and the pair of folding rolls 82 of the second folding unit 70 is conveyed.

[0063] 3, the conveying path 64B is connected to a conveying path 73 connected to the conveying path 64A on the downstream side in the conveying direction of the sheet material P. For this reason, when the sheet material P is folded only twice, for example, in a Z-fold or a tri-fold, the sheet material P is conveyed to the outside of the folding device 14 by the conveying path 64B and the conveying path 73.

[0064] 6, a pair of folding rolls 74 of the first folding unit 68 is provided upstream of the second folding unit 70 in the conveying direction of the sheet material P. In the second folding unit 70, the pair of folding rolls 74 of the first folding unit 68 also serves as an upstream roll pair, and folding rolls 74A and 74B are disposed with conveying path 64A therebetween, and sandwich the sheet material P between them to apply a conveying force to the sheet material P.

[0065] Further, downstream of the second folding unit 70 in the conveying direction of the sheet material P, a downstream roll pair 86 is provided. The downstream roll pair 86 is composed of a downstream roll 86A and a downstream roll 86B. The downstream rolls 86A and 86B are provided with their longitudinal directions intersecting the conveying direction of the sheet material P, and the downstream roll 86A and the downstream roll 86B are arranged with the conveying path 64A between them, and the downstream roll 86A and the downstream roll 86B sandwich the sheet material P and apply a conveying force to the sheet material P.

[0066] Similar to the first folding section 68 and the second folding section 70, the third folding section 72 is configured to include a pair of roll-shaped folding rolls 88 and a pushing member 90.

[0067] The folding roll pair 88 is composed of a folding roll 88A and a folding roll 88B, and the folding rolls 88A and 88B are arranged along the conveying direction of the sheet material P, with the longitudinal direction being a direction intersecting the conveying direction of the sheet material P, and apply a conveying force to the sheet material P.

[0068] On the other hand, the pushing member 90 is disposed on the opposite side of the pair of folding rolls 88 with the conveying path 64B therebetween, and is provided with its longitudinal direction intersecting the conveying direction of the sheet material P. The pushing member 90 has a sharp tip 90A, which is capable of moving toward and away from the conveying path 64B, and is capable of pushing yet another portion (position to be folded) of the sheet material P being conveyed between the folding rolls 88A and 88B.

[0069] A portion of the sheet material P is pushed between the folding rolls 88A and 88B via the pushing member 90, and the sheet material P that has been folded twice is then folded starting from another portion of the sheet material P, and as shown in Figure 7, a crease is formed in the sheet material P when it passes between the folding rolls 88A and 88B.

[0070] A conveying path 64C is provided between the folding rolls 88A and 88B in a direction intersecting with the conveying path 64B. The conveying path 64C, which branches off from the conveying path 64B, conveys the sheet material P as a conveying path 65C, and the sheet material P folded three times by the folding roll pair 74 of the first folding unit 68, the folding roll pair 82 of the second folding unit 70, and the folding roll pair 88 of the third folding unit 72 is conveyed.

[0071] 8, the conveying path 64C is connected to a conveying path 73, which is connected to the conveying paths 64A and 64B, on the downstream side in the conveying direction of the sheet material P. That is, the conveying path 73 is a conveying path where the conveying paths 64A, 64B, and 64C converge. When the sheet material P is folded three times, such as in an accordion fold or a gate fold, the sheet material P is conveyed to the outside of the folding device 14 by the conveying paths 64C and 73.

[0072] Meanwhile, a pair of folding rolls 82 of the second folding unit 70 is provided upstream of the third folding unit 72 in the conveying direction of the sheet material P. In the third folding unit 72, the pair of folding rolls 82 of the second folding unit 70 also serves as an upstream roll pair, and folding rolls 82A and 82B are disposed with conveying path 64B therebetween, and the folding rolls 82A and 82B sandwich the sheet material P and apply a conveying force to the sheet material P.

[0073] Further, a downstream roll pair 92 is provided downstream of the third folding unit 72 in the conveying direction of the sheet material P. The downstream roll pair 92 is composed of a downstream roll 92A and a downstream roll 92B. The downstream rolls 92A and 92B are provided with their longitudinal directions intersecting the conveying direction of the sheet material P, and the downstream roll 92A and the downstream roll 92B are arranged with the conveying path 64B between them, and the downstream roll 92A and the downstream roll 92B hold the sheet material P between them and apply a conveying force to the sheet material P.

[0074] In this embodiment, the folding roll pair 74 of the first folding section 68 shown in Figure 4 also serves as the upstream roll pair of the second folding section 70, and the folding roll pair 82 of the second folding section 70 also serves as the upstream roll pair of the third folding section 72, but it goes without saying that dedicated upstream roll pairs may also be provided for the second folding section 70 and the third folding section 72.

[0075] (Function of folding device) The operation of the folding device 14 according to the first embodiment will be described.

[0076] As shown in Figure 3, in an image forming device 10 equipped with the folding processing device 14 of this embodiment, if the user selects not to perform folding processing, a conveying path 63 is selected within the folding processing device 14, and the sheet material P on which an image is formed and discharged from the image forming device main body 12 is discharged outside the folding processing device 14.

[0077] On the other hand, if the user has selected to perform folding processing, the conveying path 65 is selected in the folding processing device 14, and the sheet material P discharged from the image forming apparatus main body 12 is subjected to folding processing.

[0078] For example, as shown in FIG. 9(B), a case where the sheet member P is folded gate-fold (three times) will be described with reference to FIGS. 3 and 5 to 8. FIG.

[0079] 3, the sheet material P conveyed by the conveying path 64 constituting the conveying route 65 is guided toward a guide 80 provided downstream of the first folding unit 68 in the conveying direction of the sheet material P, and the leading edge of the sheet material P abuts against an abutment portion 80A of the guide 80. As a result, the leading edges of the sheet material P are aligned.

[0080] 5, the sheet material P is subjected to a first folding process (the sheet material P is folded) in the first folding section 68. In the first folding section 68, the pushing member 76 approaches the conveying path 64, and the tip end 76A of the pushing member 76 pushes the sheet material P between the folding rolls 74A and 74B.

[0081] At this time, in the pair of folding rolls 74, folding roll 74A is driven, and a conveying force is applied to the sheet material P by the driving of folding roll 74A, and the sheet material P passes between folding roll 74A and folding roll 74B in a state where it is folded starting from a part of the sheet material P (the folding target position). As a result, fold line Q1 (see FIG. 6) is made in the sheet material P, and the sheet material P is conveyed to conveyance path 64A with fold line Q1 at the front.

[0082] Next, the sheet material P with the crease Q1 formed thereon is subjected to a second folding process in the second folding section 70, as shown in Fig. 6. In the second folding section 70, a pair of folding rolls 74 serving as an upstream roll pair is provided on the upstream side of the sheet material P in the conveying direction by the second folding section 70, and a pair of downstream rolls 86 is provided on the downstream side of the sheet material P in the conveying direction by the second folding section 70.

[0083] The sheet material P is held between the pair of folding rolls 74 and the pair of downstream rolls 86. Meanwhile, the leading edge (fold Q1) of the sheet material P is conveyed toward the conveying path 73A.

[0084] In this embodiment, in conveying path 64A, conveying roll 66A can be moved toward and away from conveying roll 66B, and in conveying path 73A, conveying roll 71A can be moved toward and away from conveying roll 71B. Therefore, in this embodiment, when the second folding process is performed in second folding section 70, conveying roll 66A moves away from conveying roll 66B and conveying roll 71A moves away from conveying roll 71B (so-called nip release state), as shown by the solid lines in Fig. 6 .

[0085] Then, while the sheet material P is sandwiched between the folding roll pair 74 as the upstream roll pair and the downstream roll pair 86, the pushing member 84 approaches the conveying path 64A, and the tip portion 84A of the pushing member 84 is pushed between the folding roll 82A and the folding roll 82B through the sheet material P.

[0086] Meanwhile, the sheet material P is pressed between the folding rolls 82A and 82B by the tip end 84A of the pressing member 84, and a conveying force is applied to the sheet material P by driving the folding roll pair 82.

[0087] The sheet material P passes between the folding rolls 82A and 82B in a state where it is folded starting from another part (the folding target position) of the sheet material P. As a result, in addition to the fold line Q1, a fold line Q2 is formed in the sheet material P, and the sheet material P is conveyed to the conveying path 64B with the fold line Q2 at the front.

[0088] Furthermore, the sheet material P with the creases Q1 and Q2 is subjected to a third folding process in the third folding section 72. In the third folding section 72, a folding roll pair 82 serving as an upstream roll pair is provided on the upstream side of the conveying direction of the third folding section 72, and a downstream roll pair 92 is provided on the downstream side of the conveying direction of the third folding section 72.

[0089] The sheet material P is then sandwiched between the folding roll pair 82 as an upstream roll pair and the downstream roll pair 92, and in this state, the pushing member 90 approaches the conveying path 64B, and the tip 90A of the pushing member 90 is pushed between the folding roll 88A and the folding roll 88B via the sheet material P.

[0090] Meanwhile, the sheet material P with the folds Q1 and Q2 is pressed between the folding rolls 88A and 88B by the tip end 90A of the pressing member 90, and a conveying force is applied by driving the pair of folding rolls 88.

[0091] The sheet material P passes between folding rolls 88A and 88B in a state where it is folded starting from another part (Q3) of the sheet material P. As a result, as shown in Fig. 7, a fold line Q3 is formed in the sheet material P in addition to the fold lines Q1 and Q2, and the sheet material P is conveyed to conveying path 64C with fold line Q3 at the front. In this way, the sheet material P is folded in a gate-fold shape (see Fig. 9(B)).

[0092] 8, the gate-folded sheet material P is transported from the transport path 64C to the transport path 73 and transported to the outside of the folding device 14 (see FIG. 3). At this time, in the transport path 73A, as shown by the solid line, the transport roll 71A is capable of contacting the transport roll 71B, and the sheet material P is transported in a nipped state by the transport roll pair 71.

[0093] In this embodiment, three folding portions 62 (first folding portion 68, second folding portion 70, and third folding portion 72) are provided to fold the sheet material P. As a result, in this embodiment, the sheet material P can be folded three times, which increases the number of folding patterns compared to when there are two or fewer folding portions.

[0094] Here, examples of folding patterns include, for example, when the sheet member P is folded twice, the Z-fold shown in Fig. 10(A), the inner three-fold shown in Fig. 10(B), the outer three-fold shown in Fig. 10(C), and the four-fold shown in Fig. 10(D). On the other hand, when the sheet member P is folded three times, examples include the gate fold shown in Fig. 9(B) and the accordion fold shown in Fig. 9(A). In other words, in this embodiment, it is possible to perform gate folds, accordion folds, etc. of the sheet member P, which were not possible when there were two or fewer folds.

[0095] Generally, in a configuration for conveying a sheet material that has been folded multiple times, for example, the dimensions of a sheet material P that has been folded only once in two are longer than the roll pitch, and therefore the sheet material P is sandwiched between multiple pairs of conveying rolls 71 and subjected to a conveying force. This can cause the sheet material P to become twisted or bent, and the accuracy of the folding position of the sheet material P can be reduced.

[0096] For this reason, in this embodiment, as shown in Figures 6 and 8, in the pair of conveying rolls 71 that make up the conveying path 73, the conveying roll 71A is configured to be able to move toward and away from the conveying roll 71B, and the sheet material P can be switched between a nip state and a nip release state.

[0097] 6, when the second folding process is performed in the second folding section 70, the transport roll 71A is separated from the transport roll 71B, and the nip is released. Therefore, in this embodiment, the accuracy of the folding position of the sheet material P is improved compared to a configuration in which the transport roll pair 71 is always in a nipped state.

[0098] On the other hand, as shown in Figure 8, when the folded sheet material P is transported outside the folding processing device 14 (see Figure 3), including transport to other processing devices such as a post-processing device that performs binding processing, the transport roll 71A in the transport path 73A is able to come into contact with the transport roll 71B, and the sheet material P is transported in a nipped state by the transport roll pair 71.

[0099] That is, in this embodiment, the conveying path 73A, which is used as a space for letting the sheet material P escape when the sheet material P is folded, is also used as a discharge path for conveying the sheet material P to the outside of the folding device 14. As a result, in this embodiment, the folding device 14 can be made smaller than in a configuration in which a dedicated space is provided for letting the sheet material P escape when the sheet material P is folded.

[0100] 6, all (three in this example) pairs of conveying rolls 71 constituting the conveying path 73A are in the nip-disengaged state. However, since the position of the leading edge of the sheet material P changes depending on the folding manner or size of the sheet material P, the number of pairs of conveying rolls 71 in the nip-disengaged state can be changed depending on the folding manner or size of the sheet material P.

[0101] 11, when the size of the sheet material P is small, the amount of penetration of the sheet material P into the transport path 73A becomes shorter than that shown in FIG. 6. Therefore, in this case, in the transport roll pair 71 (one in this case) on the downstream roll pair 86 side, the transport roll 71A is brought into contact with and separated from the transport roll 71B (nip-disengaged state), and in the transport roll pair 71 (two in this case) in the branching section 83, the transport roll 71A can come into contact with the transport roll 71B (nip state).

[0102] That is, when folding the sheet material P at the second folding unit 70, only the necessary transport roll pairs are set to the nip-disengaged state in the transport paths 64A, 73A used to release the sheet material P. As a result, in this embodiment, power consumption is reduced compared to when all transport roll pairs 71 are set to the nip-disengaged state when folding the sheet material P at the second folding unit 70.

[0103] While the present invention has been described above using one embodiment as one mode for carrying out the present invention, the present invention is not limited to this embodiment, and various modifications and substitutions can be made to the above-described embodiment without departing from the spirit and scope of the present invention. For example, the conveying path 64B is not necessarily required, and the folding device may be provided with only two folding sections. Furthermore, image formation is not necessarily required, and the folding device may be used as a dedicated folding device. [Explanation of symbols]

[0104] 10 Image forming device 12 Image forming device main body (forming section) 14 Folding device 62 Folding section 65C Transport Route 68 First fold (upstream fold, first fold) 70 Second folding section (folding section) 71 Transport Roll Pair 72 Third fold (Fold, last fold) 74 Folding roll pair (upstream roll pair) 78 Upstream Roll Pair 80 Conveyor 82 Folding roll pair (upstream roll pair) 86 Downstream Roll Pair 92 Downstream Roll Pair P sheet member (recording medium)

Claims

1. a folding unit that folds the recording medium at a middle portion in the conveying direction of the recording medium; an upstream roll pair disposed upstream of the folding portion in a conveying direction of the recording medium, and configured to convey the folded recording medium toward the folding portion; a downstream roll pair disposed downstream of the folding portion in a conveying direction of the recording medium, the downstream roll pair conveying the folded recording medium along the conveying direction; a conveyance roll pair that is arranged on the opposite side of the downstream roll pair from the folding portion, and that is located at a position where the recording medium reaches when the folding portion folds the recording medium, and that is switchable between a nip state and a nip release state; Equipped with The folding unit includes a pair of folding rolls and a pushing member, A folding processing device that brings the pair of conveying rolls into a nip-release state when the part of the recording medium is pushed between the pair of folding rolls by the pushing member in the folding section.

2. The pair of transport rolls constitutes a transport path for transporting the recording medium to another processing section, 2. The folding processing device according to claim 1, wherein the pair of transport rolls are in a nip state when the folded recording medium is transported to the other processing section.

3. 3. The folding processing device according to claim 2, wherein the folding section includes a plurality of folding sections, and the pair of transport rolls transports the recording medium folded at the final folding section to the other processing section.

4. 3. The folding processing device according to claim 2, wherein the folding section includes a plurality of folding sections, and the pair of transport rolls transports the recording medium folded at the first folding section and the last folding section to the other processing section.

5. The transport roll pairs are arranged in a plurality of directions along the transport direction, A folding device according to any one of claims 1 to 4, wherein a pair of transport rolls to be put into a nip-eliminating state is selected from among the plurality of transport roll pairs depending on the size of the recording medium and the folding manner of the recording medium.

6. a forming unit for forming an image on a recording medium; 6. An image forming apparatus comprising the folding device according to claim 1, wherein the folding section folds a recording medium on which an image has been formed in the forming section.

Images