Recording medium processing device, image formation system and program

Abstract

To inhibit displacement of a recording medium in a width direction as compared to an uninhibited configuration in which the recording medium that is conveyed by first conveying means is pulled by second conveying means.SOLUTION: Provided is a recording medium processing device comprising: first conveyance means for conveying a recording medium; a cutting member for cutting the recording medium along a conveying direction of the recording medium, disposed in parallel with the first conveyance means in the width direction of the recording medium that is conveyed; second conveyance means for conveying the recording medium that has reached a predetermined conveyance path, disposed upstream from the first conveyance means in the conveying direction; and means for inhibiting or preventing a portion overlapping the cutting means in the conveying direction, in the recording medium that is conveyed by the first conveyance means, and whose front end upstream in the conveying direction has not yet passed a predetermined conveyance path, from being pulled by the second conveyance means.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a recording medium processing device, an image forming system, and a program. [Background technology]

[0002] Patent Document 1 describes an image forming device including a first transport roller pair consisting of rotatable first and second rollers that transport paper by rotating while holding the paper in between; a rotary blade pair arranged downstream of the first transport roller pair on the paper transport path and consisting of a rotatable first and second rotary blade that cuts the paper parallel to the transport direction by rotating while holding the paper in between; and a second transport roller pair consisting of a third roller that can rotate on the same axis as the first rotary blade and a fourth roller that can rotatable on the same axis as the second rotary blade, and that transports the scraps cut by the rotary blade pair in the transport direction of the paper by rotating while holding the scraps in between, and the rotation speed of the second transport roller pair is controlled to be greater than the rotation speed of the first transport roller pair. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-203308 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the recording medium processing device, a first conveying means for conveying the recording medium and a cutting member for cutting the recording medium along the conveying direction are arranged side by side in the width direction of the recording medium being conveyed, and a second conveying means for conveying the recording medium may be provided upstream of the first conveying means in the conveying direction. Here, if the recording medium being transported by the first transport means is not prevented from being pulled by the second transport means, the recording medium may be displaced in the width direction due to being subjected to force from the cutting member and being pulled by the second transport means. An object of the present invention is to suppress displacement of the recording medium in the width direction compared to a configuration in which the recording medium being transported by the first transport means is not suppressed from being pulled by the second transport means. [Means for solving the problem]

[0005] The invention described in claim 1 is a recording medium processing device comprising: a first transport means for transporting a recording medium; a cutting member arranged alongside the first transport means in the width direction of the recording medium being transported and cutting the recording medium along the transport direction of the recording medium; a second transport means arranged upstream of the first transport means in the transport direction and transporting the recording medium that has reached a predetermined transport path; and a means for suppressing or preventing a portion of the recording medium that is transported by the first transport means and whose upstream tip in the transport direction has not passed the predetermined transport path, which overlaps with the cutting member in the transport direction, from being pulled by the second transport means. The invention described in claim 2 is the recording medium processing device described in claim 1, wherein the suppressing or preventing means is a forming means for forming slack in a portion of the recording medium that is transported by the first transport means and whose upstream leading edge in the transport direction has not passed the predetermined transport path, the portion being located between the first transport means and the second transport means in the transport direction. The invention described in claim 3 is the recording medium processing device described in claim 2, wherein the forming means is a processor that controls the conveying speed of the recording medium by the first conveying means and / or the conveying speed by the second conveying means, and the processor controls the conveying speed of the second conveying means to be faster than the conveying speed of the first conveying means. The invention described in claim 4 is the recording medium processing device described in claim 3, further comprising a third conveying means provided downstream of the first conveying means in the conveying direction, and a forming member provided between the first conveying means and the third conveying means in the conveying direction, forming a conveying path curved to one side in the thickness direction of the recording medium being conveyed, and the processor controls the conveying speed of the third conveying means to be faster than the conveying speed of the first conveying means. The invention described in claim 5 is a recording medium processing device as described in claim 4, further comprising a guide member that guides the recording medium transported by the first transport means to the transport path, and the transport path includes an overlapping transport path that overlaps with the curved transport path in the transport direction and has less curvature in the thickness direction than the curved transport path or is not curved in the thickness direction, and the guide member guides the recording medium of a predetermined type to the curved transport path and guides the recording medium of a different type to the overlapping transport path. The invention described in claim 6 is the recording medium processing device described in claim 2, wherein the forming means is a processor that controls the transportation of the recording medium by the first transporting means and the transportation of the recording medium by the second transporting means, and when the recording medium being transported by the second transporting means reaches the first transporting means, the processor sets a period during which the first transporting means is not caused to transport the recording medium and the second transporting means is caused to transport the recording medium. The invention described in claim 7 is the recording medium processing device described in claim 2, wherein the forming means is provided between the second conveying means and the first conveying means in the conveying direction and has a forming member that forms a conveying path curved on one side in the thickness direction of the recording medium being conveyed. The invention described in claim 8 is a recording medium processing device described in claim 7, wherein the forming means further has a guide member that guides the recording medium transported by the second transport means to the transport path, and the transport path has an overlapping transport path that overlaps with the curved transport path in the transport direction and has less curvature in the thickness direction than the curved transport path or is not curved in the thickness direction, and the guide member guides the recording medium of a predetermined type to the curved transport path and guides the recording medium of a different type to the overlapping transport path. A ninth aspect of the present invention is the recording medium processing device according to the second aspect, wherein the forming means forms the slack in the recording medium to a degree that satisfies a predetermined condition. The invention described in claim 10 is the recording medium processing device described in claim 1, wherein the second conveying means has a rotating member and an opposing member that faces the rotating member via the conveying path of the recording medium and presses the rotating member, and the suppressing or preventing means is a processor that suppresses or releases the pressing of the rotating member by the opposing member. The invention described in claim 11 is the recording medium processing device described in claim 10, wherein the processor suppresses or releases the pressure of the opposing member against the rotating member at least from the start of transport of the recording medium by the first transport means until a predetermined condition for the transport of the recording medium is satisfied. The invention described in claim 12 is the recording medium processing device described in claim 10, wherein the second conveying means includes at least a first second conveying means and a second second conveying means arranged outside the first second conveying means in the width direction, the cutting member is arranged outside the first conveying means in the width direction, and the processor suppresses the pressing of the rotating member by the opposing member in the second second conveying means when the recording medium is being conveyed by the first second conveying means. The invention described in claim 13 is the recording medium processing device described in claim 12, in which the processor does not suppress the pressing of the rotating member by the opposing member in the second second conveying means until the recording medium contacts the second conveying means, but suppresses the pressing when the second conveying means begins to transport the recording medium. The invention described in claim 14 is the recording medium processing device described in claim 1, further comprising a pressing member that is provided outside the cutting member in the width direction and presses the recording medium cut by the cutting member to form a fold in the recording medium along the transport direction. The invention described in claim 15 is an image forming system comprising an image forming device that forms an image on a recording medium, and a recording medium processing device that processes the recording medium on which an image has been formed by the image forming device, the recording medium processing device being configured to include the recording medium processing device described in any one of claims 1 to 14. The invention described in claim 16 is a program for causing a computer to realize a first transport function that transports a recording medium, a cutting function that cuts the recording medium being transported by the first transport function along the transport direction of the recording medium, a second transport function that transports the recording medium that has reached a predetermined transport path upstream in the transport direction of the recording medium from the transport by the first transport function, and a function of suppressing or preventing a portion of the recording medium that is transported by the first transport function and whose upstream tip in the transport direction has not passed the predetermined transport path, which overlaps with the portion cut by the cutting function in the transport direction, from being pulled by the transport by the second transport function. Effect of the Invention

[0006] According to the invention of claim 1, it is possible to suppress displacement of the recording medium in the width direction compared to a configuration in which the recording medium being transported by the first transport means is not suppressed from being pulled by the second transport means. According to the invention of claim 2, even when the recording medium is being transported by the second transport means, it is possible to prevent the portion of the recording medium that overlaps with the cutting member in the transport direction from being pulled by the second transport means. According to the invention of claim 3, it becomes unnecessary to press the recording medium in the thickness direction of the recording medium in order to form a slack in the recording medium. According to the invention of claim 4, it is possible to suppress the occurrence of wrinkles in the recording medium, compared to a configuration in which the recording medium is transported along a linear transport path from the first transport means to the third transport means. According to the invention of claim 5, the load on recording media that are not of a predetermined type can be reduced compared to a configuration in which a guide member guides the recording media into a curved transport path regardless of the type of recording media. According to the invention of claim 6, it becomes unnecessary to press the recording medium in the thickness direction of the recording medium in order to form a slack in the recording medium. According to the invention of claim 7, it is possible to suppress variation in the degree of slack formed in a recording medium passing through a curved transport path, compared to a configuration in which slack is formed in the recording medium without the recording medium passing through a transport path curved in the thickness direction. According to the invention of claim 8, the load on recording media that are not of a predetermined type can be reduced compared to a configuration in which a guide member guides the recording medium into a curved transport path regardless of the type of recording medium. According to the invention of claim 9, it is possible to suppress a decrease in the accuracy of conveyance of the recording medium, compared to a configuration in which slack is formed in the recording medium regardless of whether a predetermined condition is satisfied or not. According to the invention of claim 10, compared to a configuration in which the opposing member continues to press the rotating member, it is possible to suppress or prevent the portion of the recording medium that overlaps with the cutting member in the transport direction from being pulled by the second transport means. According to the invention of claim 11, compared to a configuration in which the pressing of the rotating member by the opposing member is no longer suppressed before a predetermined condition for the transportation of the recording medium is satisfied, it is possible to suppress or prevent the portion of the recording medium that overlaps with the cutting member in the transport direction from being pulled by the second transport means. According to the twelfth aspect of the present invention, it is possible to suppress the displacement of the recording medium in the width direction, compared to a configuration in which the pressing of the rotating member by the opposing member of the second transport means is not suppressed. According to the invention of claim 13, it is possible to suppress inclination of the recording medium with respect to the transport direction, compared to a configuration in which the pressing of the rotating member by the opposing member of the second second transport means is suppressed before the recording medium comes into contact with the second transport means. According to the invention of claim 14, even if the force that the recording medium receives in the direction opposite to the transport direction is greater than in a configuration in which a pressing member is not provided in the recording medium processing device, the recording medium can be prevented from being displaced in the left-right direction compared to a configuration in which the recording medium being transported by the first transport means is not prevented from being pulled by the second transport means. According to the invention of claim 15, it is possible to suppress displacement of the recording medium in the width direction, compared to a configuration in which the recording medium being transported by the first transport means is not suppressed from being pulled by the second transport means. According to the invention of claim 16, it is possible to suppress displacement of the recording medium in the width direction compared to a configuration in which the recording medium being transported by the first transport function is not suppressed from being pulled by transport by the second transport function. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 illustrates an image forming system. [Diagram 2] FIG. 4 is a diagram illustrating a configuration of a second post-processing device. [Diagram 3] 3 is a view of the cutting device as seen from the direction indicated by the arrow III in FIG. 2. [Figure 4] FIG. 4 is a diagram showing a cutter unit and a crease forming device. [Diagram 5] FIG. 2 is a diagram showing a hardware configuration of an information processing unit. [Figure 6] FIG. 2 is a diagram showing functions realized by an information processing unit. [Figure 7] 11A and 11B are diagrams illustrating an example in which slack is formed in a sheet of paper. [Figure 8]13A and 13B are diagrams showing modified examples of the transport of paper by the registration rolls and the transport rolls. [Figure 9] 13 is a flowchart showing a flow of a slack forming process. [Figure 10] 11 is a flowchart showing a flow of a loosening determination process. [Figure 11] FIG. 13 is a diagram showing a second post-processing device as a modified example. [Figure 12] 13 is a diagram showing an example in which a thin sheet of paper is transported by transport rolls. FIG. [Figure 13] 13 is a diagram showing an example in which a sheet of thick paper is transported by transport rolls. FIG. [Figure 14] FIG. 13 is a diagram illustrating a configuration of a second post-processing device according to a second embodiment. [Figure 15] 13 is a diagram showing an example in which a thin sheet is transported to registration rolls. FIG. [Figure 16] FIG. 13 is a diagram showing an example in which thick paper is transported by transport rolls. [Figure 17] 10 is a diagram showing the state of an upstream transport roll and a registration roll when a sheet is transported to the transport roll. FIG. [Figure 18] 13 is a flowchart showing the flow of a pressure release process. [Figure 19] FIG. 13 is a diagram showing a configuration of a registration roll according to a fourth embodiment. [Figure 20] 11 is a flowchart showing a flow of an operation process. [Figure 21] 1 is a flowchart showing a flow of processing performed by a CPU. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] <First embodiment> Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a diagram showing an image forming system 1 according to the present embodiment. The image forming system 1 includes an image forming device 2 that forms an image on paper P as an example of a recording medium, and a first post-processing device 3 and a second post-processing device 4 that perform predetermined processing on the paper P on which the image has been formed by the image forming device 2. The image forming device 2 forms an image on a sheet P using an electrophotographic method or an inkjet method.

[0009] The first post-processing device 3 is provided downstream of the image forming device 2 in the transport direction of the paper P, and performs processes on the paper P such as punching, folding, and stapling. The second post-processing device 4, which is an example of a recording medium processing device, is provided downstream of the first post-processing device 3 in the transport direction, and performs processing on the paper P such as cutting.

[0010] Fig. 2 is a diagram illustrating the configuration of the second post-processing device 4. The upper side of the second post-processing device 4 shown in Fig. 2 is sometimes referred to as the "upper side", the lower side of the second post-processing device 4 shown in Fig. 2 is sometimes referred to as the "lower side", and the up-down direction in the second post-processing device 4 shown in Fig. 2 is sometimes referred to as the "up-down direction". The back side of the second post-processing device 4 shown in Fig. 2 is sometimes referred to as the "left side", the front side of the second post-processing device 4 shown in Fig. 2 is sometimes referred to as the "right side", and the front-rear direction in the second post-processing device 4 shown in Fig. 2 is sometimes referred to as the "left-right direction".

[0011] The second post-processing device 4 is provided with an inlet 41 for receiving the paper P transported from the first post-processing device 3, and a stacking section 42 for stacking the paper P transported from the second post-processing device 4. The second post-processing device 4 is also provided with a cutting device 50 for cutting the paper P, a storage section 60 for storing the part of the paper P cut off by the cutting device 50, a sensor 50S for detecting the position of the paper P, and a registration roll 52 for adjusting the timing of transporting the paper P. The second post-processing device 4 is also provided with an upstream transport roll 43 that is provided upstream of the registration roll 52 in the transport direction and transports the paper P toward the registration roll 52, and a first downstream transport roll 44 and a second downstream transport roll 45 that are provided downstream of the cutting device 50 in the transport direction and transport the paper P toward the stacking section 42. The second post-processing device 4 is also provided with an acceptance device 40 that accepts information input by a user, and an information processing section 100 that is configured by a CPU (Central Processing Unit) that executes a program and controls the entire second post-processing device 4.

[0012] The reception device 40 is configured with a touch panel or the like, and receives information input by a user's operation. The storage section 60 is provided below the cutting device 50, and stores the portion of the paper P that is cut off by the cutting device 50 as scraps.

[0013] The upstream transport roll 43 is provided with an upstream driving roll 431 and an upstream driven roll 432 . The upstream drive roll 431 rotates by receiving a driving force from a motor (not shown). The upstream driven roll 432 is provided facing the upstream driving roll 431 via a transport path. The upstream driven roll 432 presses the upstream driving roll 431, and rotates by being driven by the upstream driving roll 431 as the upstream driving roll 431 rotates. The pressing of the upstream driving roll 431 by the upstream driven roll 432 is realized, for example, by pressing a rotation shaft (not shown) of the upstream driven roll 432 toward the upstream driving roll 431 by a pressing member (not shown). The rotation shaft (not shown) of the upstream driven roll 432 may be movable between the upstream driving roll 431 side and the opposite side to the upstream driving roll 431 side. Furthermore, a plurality of upstream transport rolls 43 may be provided side by side in the left-right direction.

[0014] The sensor 50S is provided downstream of the upstream transport roll 43 and upstream of the registration roll 52 in the transport direction, and detects the transported paper P. When the sensor 50S detects the paper P, it transmits information indicating the detection to the information processing unit 100.

[0015] The registration roll 52, which is an example of a second transport means, stops transport of the paper P when the downstream leading end in the transport direction of the paper P reaches the registration roll 52, and then transports the paper P at a predetermined timing. The registration roll 52 is provided with a registration drive roll 521 and a registration driven roll 522. A resist drive roll 521, which is an example of a rotating member, receives a driving force from a motor (not shown) and rotates. The resist driven roll 522 as an example of an opposing member is provided facing the resist driving roll 521 via a transport path. The resist driven roll 522 presses the resist driving roll 521 and rotates by being driven by the resist driving roll 521 as the resist driving roll 521 rotates. The pressing of the resist driving roll 521 by the resist driven roll 522 is realized, for example, by pressing a rotation shaft (not shown) of the resist driven roll 522 toward the resist driving roll 521 by a pressing member (not shown). The rotation shaft (not shown) of the resist driven roll 522 may be movable between the resist driving roll 521 side and the opposite side to the resist driving roll 521 side. Furthermore, a plurality of registration rolls 52 may be provided side by side in the left-right direction.

[0016] The first downstream transport roll 44, which is an example of a third transport means, is provided with a downstream driving roll 441 and a downstream driven roll 442. The downstream drive roll 441 rotates by receiving a driving force from a motor (not shown). The downstream driven roll 442 is provided opposite to the downstream driving roll 441 via a transport path. The downstream driven roll 442 presses the downstream driving roll 441 and rotates by being driven by the downstream driving roll 441 as the downstream driving roll 441 rotates. The first downstream transport roll 44 may be provided in plurality in a line in the left-right direction.

[0017] The transport paths of the paper P in the second post-processing device 4 include a first transport path R1, a second transport path R2, a third transport path R3, and a fourth transport path R4. The first transport path R1 is a transport path that passes through the cutting device 50. The second transport path R2 is a transport path that is provided above the cutting device 50 and does not pass through the cutting device 50. The third transport path R3 is provided downstream of the cutting device 50 in the transport direction, and is a transport path for the paper P passing through the first transport path R1. The fourth transport path R4 is provided downstream of the cutting device 50 in the transport direction and below the third transport path R3, and is a transport path for the paper P that has passed through the first transport path R1. The paper P that has passed through the first transport path R1 passes through either the third transport path R3 or the fourth transport path R4 and is then stacked on the stacking unit 42.

[0018] Fig. 3 is a diagram of the cutting device 50 as viewed from the direction indicated by the arrow III in Fig. 2. The left-right direction shown in Fig. 3 corresponds to the left-right direction shown in Fig. 2. As shown in FIG. 3, the cutting device 50 includes a transport roll 51, a central rotating shaft 56, an outer rotating shaft 57, a cutter unit 58, and a crease forming device 59.

[0019] The transport rolls 51, which are an example of a first transport means, transport the paper P. The cutting device 50 has five transport rolls 51 arranged in the left-right direction. The transport rolls 51 include a drive roll 511 and a driven roll 512. The driving roll 511 rotates by receiving a driving force from a motor (not shown). The driven roll 512 is provided opposite to the driving roll 511 across the transport path. The driven roll 512 presses the driving roll 511, and rotates by being driven by the driving roll 511 as the driving roll 511 rotates.

[0020] Hereinafter, one of the five transport rolls 51 located at the center in the left-right direction may be referred to as a central transport roll 51. Hereinafter, the driving roll 511 in the central transport roll 51 may be referred to as a central driving roll 511. Hereinafter, the driven roll 512 in the central transport roll 51 may be referred to as a central driven roll 512. Of the five transport rolls 51, the two transport rolls 51 located at both ends in the left-right direction may be referred to as end transport rolls 51 below. The driving rolls 511 in the end transport rolls 51 may be referred to as end driving rolls 511 below. The driven rolls 512 in the end transport rolls 51 may be referred to as end driven rolls 512 below. Moreover, of the five transport rolls 51, two transport rolls 51 located outside the central transport roll 51 and inside the end transport rolls 51 in the left-right direction may be referred to as outer transport rolls 51 below. Moreover, the driving roll 511 in the outer transport rolls 51 may be referred to as outer driving roll 511 below. Moreover, the driven roll 512 in the outer transport rolls 51 may be referred to as outer driven roll 512 below.

[0021] In addition, in the illustrated example, the driving roll 511 is provided above the driven roll 512, but the present invention is not limited to this. The driving roll 511 may be provided below the driven roll 512. In other words, the positional relationship between the driving roll 511 and the driven roll 512 in the up-down direction may be opposite to that in the illustrated example.

[0022] The central rotating shaft 56 is a rotating shaft for the central transport roll 51. The central rotating shaft 56 is provided with a central driving rotating shaft 561 and a central driven rotating shaft 562. The central driving rotation shaft 561 is a rotation shaft of the central driving roll 511. In this embodiment, the position of the central driving rotation shaft 561 is fixed in the cutting device 50. The central driving rotation shaft 561 receives a driving force from a motor (not shown) and rotates. In accordance with this rotation, the central driving roll 511 also rotates. The central driven rotation shaft 562 is a rotation shaft of the central driven roll 512. In this embodiment, the central driven rotation shaft 562 is pressed upward by a pressing member (not shown), whereby the central driven roll 512 is pressed against the central driving roll 511.

[0023] The outer rotating shaft 57 is a rotating shaft for the outer transport roll 51 and the end transport rolls 51. The outer rotating shaft 57 is provided with an outer driving rotating shaft 571 and an outer driven rotating shaft 572. The outer driving rotation shaft 571 is a rotation shaft of the outer driving roll 511 and the end driving rolls 511. In this embodiment, the position of the outer driving rotation shaft 571 is fixed in the cutting device 50. The outer driving rotation shaft 571 receives a driving force from a motor (not shown) and rotates. In accordance with this rotation, the outer driving roll 511 and the end driving rolls 511 also rotate. The outer driven rotation shaft 572 is a rotation shaft of the outer driven roll 512 and the end driven roll 512. In this embodiment, the outer driven rotation shaft 572 is pressed upward by a pressing member (not shown), whereby the outer driven roll 512 is pressed against the outer driving roll 511 and the end driven roll 512 is pressed against the end driving roll 511.

[0024] In addition, the central driven rotating shaft 562 may be fixed in position in the cutting device 50, while the central driving rotating shaft 561 may be pressed by a pressing member not shown in the figure, thereby pressing the central driving roll 511 against the central driven roll 512. In addition, the outer driven rotating shaft 572 may be fixed in position in the cutting device 50, while the outer driving rotating shaft 571 may be pressed by a pressing member not shown, so that the end driving roll 511 is pressed against the end driven roll 512.

[0025] The cutter units 58, which are an example of a cutting member, cut the paper P along the transport direction. The cutter units 58 are provided at the left and right ends of the cutting device 50 in the left-right direction. The crease forming device 59, which is an example of a pressing member, forms creases along the conveyance direction on the sheet P. The crease forming devices 59 are provided at the left end and the right end of the cutting device 50 in the left-right direction. The specific configurations of the cutter unit 58 and the crease forming device 59 will be described later.

[0026] As described above, in this embodiment, the transport rolls 51 transport the paper P while pinching and pushing the paper P. Therefore, when the paper P is transported by the transport rolls 51, the paper P receives a force from the transport rolls 51 in the transport direction. In addition, in this embodiment, the two outer transport rolls 51, the two end transport rolls 51, the two cutter units 58, and the two crease forming devices 59 are arranged symmetrically on the left and right sides with the central transport roll 51 at the center.

[0027] In addition, in this embodiment, the transport rolls 51 are arranged so that the portion of the paper P that is sandwiched between the central transport rolls 51, the portion that is sandwiched between the outer transport rolls 51, and the portion that is sandwiched between the end transport rolls 51 overlap in the transport direction.

[0028] Fig. 4 is a diagram showing the cutter unit 58 and the crease forming device 59. Note that Fig. 4 shows the cutter unit 58 and the crease forming device 59 provided at the left end portion (see Fig. 3) of the cutting device 50. As shown in FIG. 4, the cutter unit 58 is provided with a cutter 581 and a receiving member 582.

[0029] Cutter 581 is a disk-shaped blade. Cutter 581 is provided on outer driven rotation shaft 572, and the tip of the blade is aligned with receiving member 582 in the left-right direction. Also, cutter 581 is pushed from the inside (right side in the illustrated example) to the outside (left side in the illustrated example) in the left-right direction by a spring (not shown), so that the tip of the blade is pressed against receiving member 582. The receiving member 582 is provided on the outer driving rotation shaft 571. The receiving member 582 is formed in a cylindrical shape and receives the blade of the cutter 581.

[0030] The crease forming device 59 is provided with a disk 591 and a groove 592 . The disk 591 is formed in a disk shape and is provided on the outer drive rotating shaft 571. The disk 591 has an outer diameter larger than the drive roll 511 and the receiving member 582 at the end, and the tip of the disk 591 fits into the groove 592. The groove portion 592 is provided on the outer driven rotation shaft 572 and is provided so as to overlap with the disk 591 in the left-right direction. The groove portion 592 has a groove into which the tip of the disk 591 fits.

[0031] The outer driving rotation shaft 571 is provided with a driving roll 511 at its end, a disk 591, and a receiving member 582, in that order from the outer side in the left-right direction (the left side in the illustrated example). The outer driven rotation shaft 572 is provided with a driven roll 512 at its end, a groove portion 592, and a cutter 581, in that order from the outer side in the left-right direction (the left side in the illustrated example).

[0032] When the outer drive rotation shaft 571 rotates by receiving a driving force from a motor (not shown), the drive roll 511 at the end rotates, and the driven roll 512 at the end rotates with the rotation of the drive roll 511 at the end. In this state, when the paper P is sandwiched between the conveying roll 51 at the end, the cutter unit 58, and the crease forming device 59, the paper P is cut along the conveying direction by cutting the part pressed by the cutter 581 while being conveyed. Also, the paper P is conveyed while being pressed against the groove 592 by the disk 591, so that a crease is formed along the conveying direction on the paper P. Here, the part of the paper P where the crease is formed is the part of the paper P that is cut by the cutter unit 58 and becomes waste. Also, the waste of the paper P is conveyed to the conveying roll 51 at the end, and then falls and is stored in the storage section 60. In this way, when folds are formed in the scraps of paper P, the scraps of paper P become more rigid than when they are not folded, and the scraps of paper P are less likely to scatter before falling into the storage section 60, which contributes to making the storage section 60 smaller.

[0033] FIG. 5 is a diagram showing the hardware configuration of information processing unit 100. As shown in FIG. The information processing unit 100 includes a processing unit 201, an information storage device 202 for storing information, and a network interface 203 for realizing communication via a LAN (=Local Area Network) cable or the like.

[0034] The processing unit 201 is configured by a computer. The processing unit 201 has a CPU (=Central Processing Unit) 211 as an example of a processor that executes various processes described later. The processing unit 201 also has a ROM (=Read Only Memory) 212 in which software is stored, and a RAM (=Random Access Memory) 213 used as a work area. The information storage device 202 is realized by an existing device such as a hard disk drive, a semiconductor memory, or a magnetic tape. The processing unit 201, the information storage device 202, and the network interface 203 are connected via a bus 204 and a signal line (not shown).

[0035] The program executed by CPU 211 may be provided to information processing unit 100 in a state where it is stored in a computer-readable recording medium such as a magnetic recording medium (magnetic tape, magnetic disk, etc.), an optical recording medium (optical disk, etc.), a magneto-optical recording medium, a semiconductor memory, etc. In addition, the program executed by CPU 211 may be provided to information processing unit 100 using a communication means such as the Internet.

[0036] In this specification, the term "processor" refers to a processor in a broad sense, including general-purpose processors (e.g., CPU: Central Processing Unit, etc.) and dedicated processors (e.g., GPU: Graphics Processing Unit, ASIC: Application Specific Integrated Circuit, FPGA: Field Programmable Gate Array, programmable logic device, etc.). In addition, the operations of the processor may not only be performed by one processor, but may be performed by multiple processors in physically separate locations working together. The order of the operations of the processor is not limited to the order described in this embodiment, and may be changed.

[0037] Fig. 6 is a diagram showing functions realized by the information processing section 100. Note that Fig. 6 shows only functions related to the transport of paper P among the functions realized by the information processing section 100. In this embodiment, a CPU 211 as an example of a processor executes programs stored in a ROM 212 or an information storage device 202, so that an information processing unit 100 functions as a paper information acquisition unit 101, an environmental information acquisition unit 102, a usage information acquisition unit 103, a transport information acquisition unit 104, and a transport control unit 105. The processing described below is performed by each of the functional units, namely, the paper information acquisition unit 101, the environmental information acquisition unit 102, the usage information acquisition unit 103, the transport information acquisition unit 104, and the transport control unit 105. These functional units are realized by the CPU 211 executing a program, and the processing described below can also be said to be processing performed by the CPU 211 as an example of a processor.

[0038] The paper information acquisition unit 101 acquires information indicating the type of paper P to be cut by the cutter unit 58. Note that, hereinafter, the information indicating the type of paper P may be referred to as paper information. Furthermore, the type of paper P identified from the paper information includes the basis weight of the paper P, the thickness of the paper P, the length of the paper P in the transport direction, and the width of the paper P. Furthermore, the width of the paper P is the length of the paper P in the left-right direction shown in FIG. 3.

[0039] In this embodiment, the user operates a touch panel provided on the reception device 40, for example, to input information required for processing by the second post-processing device 4. The paper information acquisition unit 101 acquires paper information from the information accepted by the acceptance device 40 . The user may input information through a terminal device such as a PC (Personal Computer) connected to the image forming system 1. In this case, the paper information acquisition unit 101 acquires the paper information from the information received by the terminal device.

[0040] The environmental information acquisition unit 102 acquires information indicating indicators related to the environment of the space in which the image forming system 1 is installed. Note that, hereinafter, the information indicating indicators related to the environment of the space in which the image forming system 1 is installed may be referred to as environmental information. Indicators indicated in the environmental information include humidity, temperature, etc. In this embodiment, a sensor (not shown) is provided to detect the humidity and temperature of the space in which the image forming system 1 is installed, and the environment information acquisition unit 102 acquires the environment information from the sensor.

[0041] The usage information acquiring unit 103 acquires information indicating indicators related to the usage of the cutting device 50. The information indicating indicators related to the usage of the cutting device 50 may be referred to as usage information hereinafter. An example of an indicator indicated in the usage information is the cumulative number of sheets of paper P cut by the cutting device 50. In this embodiment, the second post-processing device 4 is provided with a counter (not shown) that counts the number of sheets of paper P cut by the cutter unit 58 each time the cutting device 50 cuts a sheet of paper P, and the usage information acquisition unit 103 acquires usage information from the counter.

[0042] The transport information acquisition unit 104 acquires information related to the transport of the paper P. Note that, hereinafter, the information related to the transport of the paper P may be referred to as transport information. An example of the transport information is information indicating the position of the paper P. In this embodiment, when the position of the paper P is detected by the sensor 50S (see FIG. 2), transport information indicating the detected position of the paper P is transmitted from the sensor 50S to the transport information acquisition unit 104.

[0043] The conveyance control unit 105 controls the conveyance of the paper P by the second post-processing device 4. When the control conditions are satisfied, the conveyance control unit 105 controls the conveyance of the paper P to form slack in the paper P between the conveyance roll 51 and the registration roll 52 in the conveyance direction. More specifically, when the control conditions are satisfied, the conveyance control unit 105 controls the conveyance by the conveyance roll 51 and the conveyance by the registration roll 52 to form slack in the paper P. The control conditions are conditions determined for the conveyance control unit 105 to control the paper P to form slack. The control conditions will be described in detail later. In this embodiment, the registration roll 52 and the transport roll 51 receive driving forces from different motors (not shown). The transport control unit 105 controls the rotation speed of each motor to control the transport speed of the registration roll 52 and the transport speed of the transport roll 51. The transport speed is the speed at which the paper P is transported.

[0044] Fig. 7 is a diagram showing an example in which slack is formed in the sheet P. Note that Fig. 7 describes the transport of the sheet P by the registration rolls 52 and the transport rolls 51 when the control conditions are satisfied. When the paper P reaches the registration roll 52, the conveyance control unit 105 controls the conveyance speed of the registration roll 52 to make the registration roll 52 convey the paper P as shown in Fig. 7(A). Note that the conveyance speed of the registration roll 52 may be hereinafter referred to as conveyance speed V1. In the illustrated example, the paper P reaches the transport roll 51. More specifically, the downstream leading end of the paper P in the transport direction reaches the nip portion N2 of the transport roll 51. In this case, the transport control unit 105 controls the transport speed of the transport roll 51 to a speed slower than the transport speed V1 of the registration roll 52, and causes the transport roll 51 to transport the paper P. The nip portion N2 of the transport roll 51 is a portion sandwiched between the drive roll 511 and the driven roll 512. The transport speed of the transport roll 51 may be referred to as the transport speed V2 below. In the example shown in FIG. 7, as described above, the transport speed V2 is slower than the transport speed V1.

[0045] Next, as the paper P is transported by the registration roll 52 and the transport roll 51, the paper P advances downstream in the transport direction as shown in Fig. 7(B). At this time, the portion of the paper P between the registration roll 52 and the transport roll 51 in the transport direction sags downward with respect to the straight dashed dotted line L1 connecting the nip portion N1 of the registration roll 52 and the nip portion N2 of the transport roll 51. More specifically, since the transport speed V1 of the registration roll 52 is faster than the transport speed V2 of the transport roll 51, the degree to which the paper P remains between the registration roll 52 and the transport roll 51 increases over time, and as a result, slack is formed in the paper P. The nip portion N1 of the registration roll 52 is a portion sandwiched between the registration drive roll 521 and the registration driven roll 522.

[0046] Next, as the transport of the paper P by the registration roll 52 and the transport roll 51 progresses further, as shown in Figure 7 (C), the paper P progresses further downstream in the transport direction and the degree of slack in the paper P between the transport roll 51 and the registration roll 52 increases. Next, as shown in Figure 7 (D), when the upstream leading edge of the paper P in the transport direction passes through the nip portion N1 of the registration roll 52, the paper P loses its slack and is transported to the transport roll 51 without being transported to the registration roll 52.

[0047] As described above, the conveyance control unit 105 forms slack in the paper P to prevent the paper P from being pulled by the conveyance rolls 51 and the registration rolls 52. In other words, the CPU 211 prevents the portion of the paper P that is conveyed by the conveyance rolls 51 and whose leading edge on the upstream side in the conveyance direction has not passed through the predetermined conveyance path, which overlaps with the cutter unit 58 in the conveyance direction, from being pulled by the registration rolls 52. An example of the predetermined conveyance path is the nip portion N1 of the registration rolls 52.

[0048] In this embodiment, cutter units 58 are provided at the left-right ends of the cutting device 50 (see FIG. 3), and when the paper P is transported to the transport rolls 51, the left-right ends of the paper P are pressed by the cutter 581 of the cutter unit 58. In this case, the transport speed is likely to decrease in the portion of the paper P pressed by the cutter 581 and in the vicinity of this portion, due to the force applied in the opposite direction to the transport direction. In particular, in this embodiment, the crease forming device 59 is provided at the left-right end of the cutting device 50, and when the paper sheet P is transported to the cutting device 50, the left-right end of the paper sheet P is pressed by a disk 591 of the crease forming device 59. In this case, the conveying speed is likely to decrease in the portion of the paper sheet P pressed by the disk 591 and in the vicinity of this portion due to the force applied in the opposite direction to the conveying direction. Thus, in the portion of the paper P that overlaps with the cutting device 50 in the transport direction, the transport speed is more likely to decrease at the ends than at the center in the left-right direction.

[0049] Furthermore, when the portion of the paper P that overlaps with the cutting device 50 in the transport direction is pulled by the resist roll 52, the transport speed of the portion of the paper P that is transported by the transport roll 51 is further reduced, and in this case, the difference in transport speed in the left and right direction of the paper P becomes large. In other words, in the portion of the paper P that overlaps with the cutting device 50 in the transport direction, the degree of delay in the transport speed of the ends in the left and right direction becomes large compared to the transport speed of the center in the left and right direction. Note that the left and right direction of the paper P is the left and right direction shown in FIG. 3. The left and right direction of the paper P can also be regarded as the width direction of the paper P.

[0050] When the degree of delay in the conveying speed of the end portions of the paper P becomes large with respect to the conveying speed of the center portion in the left-right direction, the paper P is easily pulled by the force that the center portion in the left-right direction of the paper P receives in the conveying direction and the force that the end portions in the left-right direction of the paper P receive on the opposite side of the conveying direction. More specifically, the center portion and the end portions in the left-right direction of the paper P are easily pulled in opposite directions. In this case, a rotational moment acts on the end portions in the left-right direction of the paper P, and the central portion in the left-right direction of the paper P is easily bent in the portion of the paper P upstream of the cutting device 50 in the conveying direction. In other words, both ends in the left-right direction of the paper P are easily displaced toward the center portion in the portion of the paper P upstream of the cutting device 50 in the conveying direction, and in this case, the portion of the paper P cut by the cutter unit 58 may vary.

[0051] In contrast, in this embodiment, when slack is formed in the paper P between the transport rolls 51 and the registration rolls 52 in the transport direction, the tugging of the paper P between the transport rolls 51 and the registration rolls 52 is alleviated by the slack in the paper P. In this case, compared to a configuration in which the paper P transported by the transport rolls 51 is not prevented from being pulled by the registration rolls 52, the displacement of both ends of the paper P in the left-right direction toward the center is suppressed by the amount that the tugging of the paper P is alleviated. Therefore, the occurrence of variation in the portion of the paper P cut by the cutter unit 58 is suppressed.

[0052] As shown in FIG. 7, the transport control unit 105 controls the transport speed V1 of the registration rolls 52 to be faster than the transport speed V2 of the transport rolls 51. In this case, it is not necessary to press the paper P in the thickness direction of the paper P in order to form a slack in the paper P. The thickness direction of the paper P is the up-down direction in FIG.

[0053] In the above example, the transport control unit 105 controls both the transport speed of the transport roll 51 and the transport speed of the registration roll 52, but the present invention is not limited to this. As long as the conveying control unit 105 controls the conveying speed of the resist roll 52 to be faster than the conveying speed of the conveying roll 51, it is not necessary to control one of the conveying speed of the conveying roll 51 and the conveying speed of the resist roll 52 and not the other.

[0054] Furthermore, the conveyance control unit 105 controls the conveyance of the paper P so as to form slack in the paper P that satisfies the slackness condition. The slackness condition is a condition that is determined for the degree of slackness to be formed in the paper P from the viewpoint of suppressing a decrease in the accuracy of conveyance of the paper P. The degree of slackness may be the vertical length of the portion of the paper P where slackness is formed from the dashed dotted line L1 that connects the nip portion N1 and the nip portion N2.

[0055] One of the slack conditions is that the degree of slack formed in the paper P is equal to or greater than a predetermined lower limit. If the degree of slack formed in the paper P is excessively small, the degree of relaxation due to the slack in the pulling of the paper P between the transport roll 51 and the registration roll 52 is small, and in this case, the left and right ends of the paper P may be displaced toward the left and right center. Therefore, a lower limit value of the degree of slack formed in the paper P is set so that the displacement of the paper P that may occur in the paper P does not exceed an allowable degree. In addition, a lower limit value of the subtraction value obtained by subtracting the value of the transport speed V2 from the value of the transport speed V1 is set according to the lower limit value of the degree of slack formed in the paper P, and the transport speed V1 and the transport speed V2 are controlled by the transport control unit 105 so that the subtraction value is equal to or greater than the lower limit value.

[0056] Also, one of the slack conditions is that the degree of slack formed in the paper P is equal to or less than a predetermined upper limit. If the degree of slack formed in the paper P is excessively large, a paper jam may occur due to this slack. Therefore, an upper limit of the degree of slack formed in the paper P is set so that a paper jam does not occur before the leading edge on the upstream side in the conveying direction of the paper P passes through the nip portion N1 of the registration roll 52. In addition, an upper limit of the subtraction value obtained by subtracting the value of the conveying speed V2 from the value of the conveying speed V1 is set according to the upper limit of the degree of slack formed in the paper P, and the conveying speed V1 and the conveying speed V2 are controlled by the conveying control unit 105 so that the subtraction value is equal to or less than the upper limit.

[0057] In this manner, the conveyance control unit 105 creates slack in the paper P to the extent that the slackness condition is satisfied. In this case, the accuracy of conveying the paper P is prevented from decreasing, compared to a configuration in which slack is formed in the paper P regardless of whether the slack condition is satisfied or not.

[0058] In this embodiment, the crease forming device 59 is provided outside the cutter unit 58 in the left-right direction, and presses the paper P cut by the cutter unit 58 to form a crease in the paper P along the conveying direction. In this case, even if the force that the paper P receives in the direction opposite to the conveying direction is greater than in a configuration in which the second post-processing device 4 does not have a crease forming device 59, the paper P is prevented from being displaced in the left-right direction compared to a configuration in which the paper P being conveyed by the conveying roll 51 is not prevented from being pulled by the registration roll 52.

[0059] <Modification> Next, a modified example of the transport of the paper P by the registration rolls 52 and the transport rolls 51 will be described. The method of transporting the paper P by the registration rolls 52 and the transport rolls 51 to form slack in the paper P is not limited to the example shown in FIG. Fig. 8 is a diagram showing a modified example of the transport of the paper P by the registration rolls 52 and the transport rolls 51. In Fig. 8, the transport of the paper P by the registration rolls 52 and the transport rolls 51 when the control conditions are satisfied will be described.

[0060] When the paper P reaches the registration rolls 52, the transport control unit 105 causes the registration rolls 52 to transport the paper P at a transport speed V1, as shown in Fig. 8(A). In the illustrated example, the downstream leading edge of the paper P in the transport direction reaches the nip portion N2 of the transport rolls 51. In this case, in the modified example, the transport control unit 105 does not operate the transport rolls 51 and does not cause the transport rolls 51 to start transporting the paper P.

[0061] In this case, the sheet P is retained between the registration roll 52 and the transport roll 51, and slack is formed in the sheet P as shown in FIG. 8(B). Then, when the degree of slack formed in the paper P satisfies the slack condition, the transport roll 51 transports the paper P at a transport speed V2 that is equal to or lower than the transport speed V1, as shown in FIG. 8(C). In this manner, in the modified example, the conveying speed V2 may be slower than the conveying speed V1, or may be the same as the conveying speed V1. In addition, in the modified example, since slack is formed in the paper P before the conveying roll 51 starts conveying the paper P, it is not necessary to form slack in the paper P due to the speed difference between the conveying speed V1 and the conveying speed V2.

[0062] In addition, when the conveying speed V1 is slower than the conveying speed V2, the conveying control unit 105 controls the conveying speed V1 and the conveying speed V2 so that the slack formed in the paper P satisfies the slackness condition until the paper P passes through the nip portion N1 of the registration roll 52.

[0063] As described above, the conveying control unit 105 forms slack in the portion of the paper P that is conveyed by the conveying roll 51 and whose upstream tip in the conveying direction has not passed through a predetermined conveying path, the portion being positioned between the conveying roll 51 and the registration roll 52 in the conveying direction. In this case, even when the paper P is being transported to the registration rolls 52, the portion of the paper P that overlaps with the cutter unit 58 in the transport direction is prevented from being pulled by the registration rolls 52.

[0064] In addition, the CPU 211 can also be regarded as a forming means for forming slack in the portion of the paper P that is transported by the transport roll 51 and whose upstream tip in the transport direction has not passed through a predetermined transport path, which is located between the transport roll 51 and the registration roll 52 in the transport direction.

[0065] In addition, when the paper P being transported to the registration rolls 52 reaches the transport rolls 51, the transport control unit 105 provides a period during which the transport rolls 51 do not transport the paper P but transport the paper to the registration rolls 52. In this case, it is no longer necessary to press the sheet P in the thickness direction of the sheet P in order to create slack in the sheet P.

[0066] 9 is a flow chart showing the flow of the slack forming process. The slack forming process is a process in which the information processing unit 100 forms slack in the paper P. In this embodiment, the slack forming process is started when an instruction to cut the paper P by the cutting device 50 is given. Furthermore, the information processing unit 100 determines that an instruction to cut the paper P by the cutting device 50 is given by the paper information acquisition unit 101 acquiring paper information.

[0067] The transport control unit 105 determines whether the paper P has reached the registration rolls 52 (step (hereinafter referred to as "S") 101). The transport control unit 105 determines whether the paper P has reached the registration rolls 52 based on whether transport information has been acquired by the transport information acquisition unit 104 and the position of the paper P indicated in the transport information acquired by the transport information acquisition unit 104. Also, while a negative result continues (NO in S101), the process of S101 is repeated. When the paper P reaches the registration rolls 52 (YES in S101), the transport control unit 105 causes the registration rolls 52 to transport the paper P at a transport speed V1 (S102).

[0068] Next, the conveyance control unit 105 determines whether or not a start condition is satisfied (S103). The start condition is a condition that is set so that the conveyance control unit 105 causes the conveyance roll 51 to start conveying the paper P. The start condition differs depending on whether the conveyance control unit 105 forms slack in the paper P by the method shown in FIG. 7 or the method shown in FIG.

[0069] 7, the start condition is set to be that the leading edge of the paper P on the downstream side in the transport direction reaches the nip portion N2 (see FIG. 7) of the transport rolls 51. The transport control unit 105 determines whether the leading edge of the paper P has reached the transport rolls 51 based on the relationship between the position of the paper P indicated in the transport information acquired by the transport information acquisition unit 104 and the transport speed V1 of the registration rolls 52. 8, the start condition is not satisfied even when the downstream leading edge of the paper P in the conveying direction reaches the nip N2 of the conveying roll 51, and slack is formed in the paper P. In this case, the start condition is determined to be that the degree of slack formed in the paper P satisfies the slack condition. The conveying control unit 105 specifies the degree of slack formed in the paper P from the relationship between the time elapsed since the start of conveyance of the paper P by the registration roll 52 and the conveying speed V1 of the registration roll 52, and determines whether the specified degree of slack satisfies the slack condition. As long as a negative result remains in S103 (NO in S103), the process of S103 is repeated.

[0070] Furthermore, when the start condition is satisfied (YES in S103), the transport control unit 105 causes the transport roll 51 to transport the paper P at a transport speed V2 (S104). Here, when the transport control unit 105 forms slack in the paper P using the method shown in Fig. 7, the transport speed V2 is slower than the transport speed V1. When the transport control unit 105 forms slack in the paper P using the method shown in Fig. 8, the transport speed V2 is equal to or lower than the transport speed V1.

[0071] In the example shown in FIG. 8, the transport control unit 105 provides a period during which the transport rolls 51 do not start transporting the paper P after the paper P reaches the transport rolls 51, but the present invention is not limited to this. The transport control unit 105 may provide a period during the transport of the paper P by the transport rolls 51 after the transport of the paper P has started, during which the transport rolls 51 do not transport the paper P but the registration rolls 52 transport the paper. Then, when the slack formed in the paper P satisfies the slackness condition, the transport control unit 105 may restart the transport of the paper P by the transport rolls 51.

[0072] Fig. 10 is a flow chart showing the flow of loosening determination processing. The loosening determination processing is processing in which the information processing unit 100 determines whether or not to perform loosening formation processing (see Fig. 9). In this embodiment, the loosening determination processing is started every time an instruction to form an image by the image forming apparatus 2 (see Fig. 1) is issued. Furthermore, when the information processing unit 100 acquires information from the image forming apparatus 2 indicating that an instruction to form an image has been issued, it determines that an instruction to form an image has been issued.

[0073] The conveyance control unit 105 determines whether or not an instruction to cut the paper P by the cutting device 50 has been issued (S201). The conveyance control unit 105 determines whether or not an instruction to cut the paper P has been issued, depending on whether or not the paper information acquisition unit 101 has acquired paper information. If there is no instruction to cut the paper P (NO in S201), the slackness determination process ends. In this case, the paper P is transported to the stacking unit 42 via the second transport path R2 (see FIG. 2) in the second post-processing device 4, so the cutting device 50 does not cut the paper P and transport the paper P, and the slackness formation process is not performed.

[0074] When an instruction to cut the paper P is given (YES in S201), the conveyance control unit 105 determines whether the basis weight of the paper P to be cut by the cutting device 50 is equal to or less than a predetermined basis weight threshold (S202). The paper P to be cut by the cutting device 50 may be referred to as the target paper P below. The conveyance control unit 105 determines whether the basis weight of the target paper P indicated in the paper information acquired by the paper information acquisition unit 101 is equal to or less than a predetermined basis weight threshold. Also, one of the control conditions is that the basis weight of the target paper P is equal to or less than the predetermined basis weight threshold.

[0075] The threshold value of the basis weight of the paper P is determined from the viewpoint of the ease of displacement of the paper P when it is transported to the cutting device 50. The smaller the basis weight of the paper P, the lower the rigidity of the paper P. Therefore, when the paper P is transported to the transport rolls 51, the paper P is more likely to be displaced in the left-right direction due to the action of the cutter unit 58 (see FIG. 3) and the crease forming device 59, or due to being pulled by the registration rolls 52. Therefore, the basis weight of the paper P that exceeds the allowable level of displacement of the paper P that may occur when the paper P is transported to the transport rolls 51 in a case where the paper P is not prevented from being pulled by the registration rolls 52 is determined as the threshold value.

[0076] If the basis weight of the target paper P is greater than the predetermined basis weight threshold (NO in S202), the transport control unit 105 determines whether the thickness of the target paper P is equal to or less than the predetermined thickness threshold (S203). The transport control unit 105 determines whether the thickness of the target paper P indicated in the paper information acquired by the paper information acquisition unit 101 is equal to or less than the predetermined thickness threshold. In addition, one of the control conditions is that the thickness of the target paper P is equal to or less than the predetermined thickness threshold. The threshold thickness of the paper P is determined from the viewpoint of the ease of displacement of the paper P when it is transported by the transport rolls 51, similarly to the threshold basis weight of the paper P. In this embodiment, the threshold thickness is determined to be a thickness of the paper P that exceeds an allowable degree of displacement of the paper P that may occur when the paper P is transported by the transport rolls 51 in a case where the paper P is not prevented from being pulled by the registration rolls 52.

[0077] If the thickness of the target paper P is greater than the predetermined thickness threshold (NO in S203), the transport control unit 105 determines whether the width of the target paper P is equal to or greater than the predetermined width threshold (S204). The transport control unit 105 determines whether the width of the target paper P indicated in the paper information acquired by the paper information acquisition unit 101 is equal to or greater than the predetermined width threshold. In addition, one of the control conditions is that the width of the target paper P is equal to or greater than the predetermined width threshold.

[0078] The threshold value of the width of the paper P is determined from the viewpoint of the ease of displacement of the paper P when it is transported by the transport rolls 51. The longer the width of the paper P, the more easily the left and right ends of the paper P are displaced toward the center in the left and right direction when it is transported by the transport rolls 51 due to the action of the cutter unit 58 (see FIG. 3) and the crease forming device 59, or due to being pulled by the registration rolls 52. Therefore, the threshold value is determined to be the width of the paper P that exceeds the allowable degree of displacement of the paper P that may occur when the paper P is transported by the transport rolls 51 in a case where the paper P is not prevented from being pulled by the registration rolls 52.

[0079] If the width of the target paper P is less than the predetermined width threshold (NO in S204), the transport control unit 105 determines whether the length of the target paper P in the transport direction is equal to or greater than the predetermined transport direction threshold (S205). The transport control unit 105 determines whether the length of the target paper P in the transport direction indicated in the paper information acquired by the paper information acquisition unit 101 is equal to or greater than the predetermined transport direction threshold. In addition, one of the control conditions is that the length of the target paper P in the transport direction is equal to or greater than the predetermined transport direction threshold.

[0080] The threshold value of the length of the sheet P in the transport direction is determined from the viewpoint of the ease of displacement of the sheet P when it is transported by the transport rolls 51. When the sheet P is displaced in the left-right direction over time as it is subjected to the action of the cutter unit 58 and the crease forming device 59 or pulled by the registration rolls 52 when it is transported by the transport rolls 51, the degree of displacement becomes greater toward the upstream side in the transport direction of the sheet P. Therefore, the length of the sheet P in the transport direction that exceeds the allowable degree of displacement of the sheet P that may occur when the sheet P is transported by the transport rolls 51 in the case where the sheet P is not prevented from being pulled by the registration rolls 52 is determined as the threshold value.

[0081] If the length of the target paper P in the transport direction is less than a predetermined threshold value of the length in the transport direction (NO in S205), the transport control unit 105 determines whether the humidity in the space in which the image forming system 1 is installed is equal to or greater than a predetermined humidity threshold value (S206). The transport control unit 105 determines whether the humidity indicated in the environmental information acquired by the environmental information acquisition unit 102 is equal to or greater than a predetermined humidity threshold value. In addition, one of the control conditions is that the humidity in the space in which the image forming system 1 is installed is equal to or greater than a predetermined humidity threshold value.

[0082] The humidity threshold of the space where the image forming system 1 is provided is determined from the viewpoint of the ease of displacement of the paper P when it is transported by the transport rolls 51. The higher the humidity of the space where the image forming system 1 is provided, the lower the rigidity of the paper P. In addition, the lower the rigidity of the paper P, the more easily the ends in the left and right direction of the paper P are displaced toward the center in the left and right direction when the paper P is transported by the transport rolls 51 due to the action of the cutter unit 58 and the crease forming device 59, or being pulled by the registration rolls 52. Therefore, the humidity that exceeds the allowable level of displacement of the paper P that may occur when the paper P is transported by the transport rolls 51 in the case where the paper P is not prevented from being pulled by the registration rolls 52 is determined as the threshold.

[0083] If the humidity in the space in which the image forming system 1 is installed is lower than a predetermined humidity threshold (NO in S206), the transport control unit 105 determines whether the temperature in the space in which the image forming system 1 is installed is equal to or higher than a predetermined temperature threshold (S207). The transport control unit 105 determines whether the temperature indicated in the environmental information acquired by the environmental information acquisition unit 102 is equal to or higher than a predetermined temperature threshold. In addition, it is one of the control conditions that the temperature in the space in which the image forming system 1 is installed is equal to or higher than a predetermined temperature threshold.

[0084] The threshold temperature of the space in which the image forming system 1 is provided is determined from the viewpoint of the ease of displacement of the paper P when it is transported by the transport rolls 51. The higher the temperature of the space in which the image forming system 1 is provided, the lower the rigidity of the paper P becomes, and the left and right ends of the paper P become more likely to be displaced toward the center in the left and right direction when it is transported by the transport rolls 51 due to the action of the cutter unit 58 and the crease forming device 59, or due to being pulled by the registration rolls 52. Therefore, a temperature that exceeds an allowable level of displacement of the paper P that may occur when the paper P is transported by the transport rolls 51 in a case where the paper P is not prevented from being pulled by the registration rolls 52 is determined as the threshold temperature.

[0085] If the temperature of the space in which the image forming system 1 is installed is lower than a predetermined temperature threshold (NO in S207), the conveyance control unit 105 determines whether or not the usage conditions are satisfied (S208). In this embodiment, the usage conditions are determined such that the cumulative number of sheets P cut by the cutter unit 58 is equal to or greater than a predetermined threshold number. The conveyance control unit 105 determines whether or not the cumulative number of sheets indicated in the usage information acquired by the usage information acquisition unit 103 is equal to or greater than a predetermined threshold number. The usage conditions are also one of the control conditions.

[0086] The threshold value for the cumulative number of sheets of paper P cut by cutter unit 58 is determined from the perspective of how easily the sheets of paper P are displaced when transported by transport rolls 51. The greater the cumulative number of sheets of paper P cut by cutter unit 58, the greater the degree of wear on the blade of cutter 581 (see FIG. 4 ), and the greater the force required for cutter 581 to cut sheets of paper P. When the force required for cutter 581 increases, the left and right ends of the sheets of paper P are more likely to be displaced toward the left and right center by the action of cutter 581 when transported by transport rolls 51. Therefore, a threshold value is set as the cumulative number of sheets of paper P cut by the cutter unit 58 such that the displacement of the paper P that may occur when the paper P is transported to the cutting device 50 exceeds an acceptable level when the paper P is not prevented from being pulled by the resist roll 52.

[0087] If the cumulative number of sheets P cut by the cutter unit 58 is less than the threshold value (NO in S208), the conveyance control unit 105 conveys the sheet P without performing slack forming processing (S209). In other words, the conveyance control unit 105 conveys the sheet P without forming slack in the sheet P. Moreover, if a positive result is obtained in any of S202 to S208, the conveyance control unit 105 performs a slack forming process (S210).

[0088] When the paper P conveyed to the cutting device 50 is a paper bundle of a plurality of sheets bound together, the subject of the determination in S202 and S203 may be the basis weight or thickness of the paper bundle. In the above example, all of steps S202 to S208 in the loosening determination process are set as the control conditions, but the present invention is not limited to this. The control condition may be at least one of steps S202 to S208 in the loosening determination process.

[0089] In the above example, the usage condition is that the cumulative number of sheets of paper P cut by the cutter unit 58 is equal to or greater than a predetermined threshold number, but the usage condition is not limited to this. A usage condition may be that the cumulative distance of transport of the paper P by at least one of the central transport roll 51, the outer transport roll 51, and the end transport roll 51 is equal to or greater than a predetermined distance threshold. In addition, the usage condition may be that the cumulative number of revolutions of at least one of the central transport roll 51, the outer transport roll 51, and the end transport roll 51 is equal to or greater than a predetermined threshold value of the number of revolutions. Furthermore, the condition for use may be that the period during which the second post-processing device 4 has been used is equal to or longer than a predetermined threshold period.

[0090] In addition, in the present embodiment, the slack forming process is not performed if none of the control conditions are satisfied; however, the present invention is not limited to this. When none of the control conditions are satisfied, the slack forming process may be performed so that a smaller degree of slack is formed in the paper P compared to when any one of the control conditions is satisfied.

[0091] (Modification of the second post-processing device 4) Next, a description will be given of a modified example of the second post-processing device 4. The second post-processing device 4 is not limited to the configuration shown in FIG. Fig. 11 is a diagram showing a modified second post-processing device 4. Fig. 11 shows the configuration between the transport roll 51 and the first downstream transport roll 44 in the transport direction of the second post-processing device 4.

[0092] 11, in the second post-processing device 4 as a modified example, two first transport paths R1 are provided between the transport roll 51 and the first downstream transport roll 44 in the transport direction. More specifically, the first transport path R1 between the transport roll 51 and the first downstream transport roll 44 in the transport direction includes a lower first transport path R11 and an upper first transport path R12. The lower first transport path R11 and the upper first transport path R12 overlap in the transport direction. The first lower transport path R11, which is an example of a curved transport path, is a transport path that is recessed downward with respect to a straight dashed dotted line L2 that connects the nip portion N2 of the transport roll 51 and the nip portion N3 of the first downstream transport roll 44. The nip portion N3 of the first downstream transport roll 44 is a portion sandwiched between the downstream driving roll 441 and the downstream driven roll 442. The upper first transport path R12, which is an example of an overlapping transport path, is a transport path located above the lower first transport path R11 and extends along the dashed line L2.

[0093] Further, the second post-processing device 4 is provided with a transport path section 71 and a switching gate 72. The transport path section 71 is a wall section that forms the lower first transport path R11 and the upper first transport path R12. The transport path section 71 is provided with a lower transport path section 711 and an upper transport path section 712. The lower transport path portion 711, which is an example of a forming member, forms the lower first transport path R11. The lower transport path portion 711 is provided below the lower first transport path R11 and is a wall portion that is recessed downward along the lower first transport path R11. The upper conveying path section 712 forms the upper first conveying path R12. The upper conveying path section 712 is provided above the lower conveying path section 711 and is a wall section provided along the dashed dotted line L2. In other words, the upper conveying path section 712 is a wall section provided above the upper first conveying path R12 along the upper first conveying path R12.

[0094] The switching gate 72 as an example of the guide member is a metal plate provided between the transport roll 51 and the first downstream transport roll 44 in the transport direction, and switches the transport path through which the paper P passes between the lower first transport path R11 and the upper first transport path R12. The switching gate 72 is provided extending linearly, and rotates in a clockwise direction and a counterclockwise direction about a rotation axis (not shown). More specifically, the switching gate 72 does not rotate when it receives a force less than a predetermined value in the rotation direction, and rotates when it receives a force equal to or greater than a predetermined value in the rotation direction. An example of the force equal to or greater than the predetermined value is a force acting on the switching gate 72 when the paper P as thick paper hits the switching gate 72. An example of the thick paper is a paper P having a basis weight threshold value and a thickness threshold value both of which are determined as control conditions. In the illustrated example, the switching gate 72 is provided opposite the lower transport path portion 711 across the lower first transport path R11, and is provided along the lower transport path portion 711.

[0095] 12 is a diagram showing an example of a case where a sheet of paper P as thin paper is transported by transport rolls 51. Note that an example of thin paper is a sheet of paper P that is equal to or less than a threshold value for basis weight and a threshold value for thickness both of which are determined as control conditions. Also, hereinafter, the sheet of paper P as thin paper may be referred to as thin paper P1. 12A, as the thin paper P1 is transported by the transport roll 51, the leading edge on the downstream side in the transport direction hits the switching gate 72. In this case, the switching gate 72 is pushed by the thin paper P1, but does not rotate because the force it receives from the thin paper P1 is small.

[0096] In this case, as shown in FIG. 12B, the thin paper sheet P1 travels along the switching gate 72 and the lower transport path portion 711, and thus passes through the lower first transport path R11 while curving. Next, as the transport of the thin paper P1 by the transport roll 51 progresses, the downstream leading end of the thin paper P1 in the transport direction reaches the first downstream transport roll 44, as shown in Fig. 12(C). At this time, slack is formed in the thin paper P1 in the portion between the transport roll 51 and the first downstream transport roll 44 in the transport direction. More specifically, slack is formed in the thin paper P1 as the thin paper P1 is transported along the lower first transport path R11 while passing between the switching gate 72 and the lower transport path section 711.

[0097] 12(D), the transport control unit 105 causes the first downstream transport roll 44 to transport the thin paper P1 at a transport speed faster than the transport speed V2. The transport speed of the first downstream transport roll 44 may be referred to as the transport speed V3 below. As described above, the transport speed V3 is faster than the transport speed V2.

[0098] 13 is a diagram showing an example in which a sheet of paper P as thick paper is transported by transport rolls 51. As described above, an example of thick paper is a sheet of paper P that is larger than the threshold value of basis weight defined as a control condition and larger than the threshold value of thickness defined as a control condition. In addition, the sheet of paper P as thick paper may be referred to as thick paper P2 below. As shown in FIG. 13A, when the cardboard P2 is transported by the transport rolls 51, the leading edge of the cardboard P2 on the downstream side in the transport direction abuts against the switching gate 72.

[0099] In this case, as shown in Fig. 13(B), the switching gate 72 is pushed by the thick sheet P2 to rotate counterclockwise and is provided along the upper first transport path R12. The thick sheet P2 passes through the upper first transport path R12 without bending by proceeding along the switching gate 72 and the upper transport path section 712. Additionally, the thick sheet P2 is more rigid than the thin sheet P1 (see Fig. 12(B)), and therefore proceeds along the upper first transport path R12 without sagging. Furthermore, when the downstream leading edge of the cardboard P2 in the conveying direction reaches the first downstream conveying roll 44, as shown in Figure 13 (C), the conveying control unit 105 causes the first downstream conveying roll 44 to convey the cardboard P2 at a conveying speed V3 that is faster than the conveying speed V2.

[0100] As described above, the lower transport path section 711 is provided between the transport roll 51 and the first downstream transport roll 44 in the transport direction, and forms a lower first transport path R11 curved to one side in the thickness direction of the paper P being transported, and the transport control section 105 controls the transport speed V3 of the first downstream transport roll 44 to be faster than the transport speed V2 of the transport roll 51.

[0101] In this embodiment, in order to increase the efficiency of transporting the paper P, the transport control unit 105 controls the transport speed V3 to be faster than the transport speed V2. In this case, when the paper P is transported by the transport roll 51 and the first downstream transport roll 44, the paper P may be pulled by the transport roll 51 and the first downstream transport roll 44, causing wrinkles to occur in the paper P. In contrast, when slack is formed in the paper P as the paper P is transported along the lower first transport path R11, the pulling of the paper P between the transport roll 51 and the first downstream transport roll 44 is alleviated by the slack of the paper P. In this case, the paper P is less likely to be wrinkled compared to a configuration in which the paper P is transported from the transport roll 51 to the first downstream transport roll 44 along a linear transport path.

[0102] The switching gate 72 guides the paper P of a predetermined type to the lower first transport path R11, and guides the paper P of a different type to the upper first transport path R12. An example of the paper P of a predetermined type is thin paper P1. An example of the paper P of a different type is thick paper P. In this case, the load on the thick paper P is reduced compared to a configuration in which the switching gate 72 guides the paper P to the lower first transport path R11 regardless of the type of paper P.

[0103] In the above example, the upper first transport path R12 is described as a transport path that is not curved in the thickness direction of the transported paper P, but the present invention is not limited to this. The upper first transport path R12 may be a transport path that is curved in the thickness direction of the transported paper P to a lesser extent than the lower first transport path R11. In other words, the upper first transport path R12 may be a transport path that is less curved in the thickness direction than the lower first transport path R11 or is not curved in the thickness direction at all.

[0104] <Second embodiment> Next, the second post-processing device 4 of the second embodiment will be described. In the first embodiment, it has been described that slack is formed in the paper P by controlling the transport of the registration roll 52 and the transport of the transport roll 51. Here, the configuration of the second post-processing device 4 for forming slack in the paper P is not limited to that described in the first embodiment. Note that, for the second embodiment, the configuration of the second post-processing device 4 that is different from that of the first embodiment will be mainly described, and the description of the same configuration as that of the second post-processing device 4 of the first embodiment may be omitted. Fig. 14 is a diagram showing the configuration of the second post-processing device 4 of the second embodiment. Fig. 14 shows the configuration of the second post-processing device 4 from the registration roll 52 to the transport roll 51 in the transport direction.

[0105] 14, in the second post-processing device 4 of the second embodiment, two first transport paths R1 are provided between the registration roll 52 and the transport roll 51 in the transport direction. More specifically, the first transport path R1 between the registration roll 52 and the transport roll 51 in the transport direction includes a lower first transport path R13 and an upper first transport path R14. The lower first transport path R13 and the upper first transport path R14 overlap in the transport direction. The lower first transport path R13, which is an example of a curved transport path, is a transport path that is recessed downward with respect to a straight dashed dotted line L1 connecting the nip portion N1 of the registration roll 52 and the nip portion N2 of the transport roll 51. The upper first transport path R14, which is an example of an overlapping transport path, is a transport path located above the lower first transport path R13 and extends along the dashed dotted line L1.

[0106] Further, the second post-processing device 4 is provided with a transport path section 73 and a switching gate 74. The transport path section 73, which is an example of a forming means, is a wall section that forms the lower first transport path R13 and the upper first transport path R14. The transport path section 73 is provided with a lower transport path section 731 and an upper transport path section 732. The lower transport path portion 731, which is an example of a forming member, forms the lower first transport path R13. The lower transport path portion 731 is provided below the lower first transport path R13 and is a wall portion that is recessed downward along the lower first transport path R13. The upper conveying path portion 732 forms the upper first conveying path R14. The upper conveying path portion 732 is provided above the lower conveying path portion 731 and is a wall portion provided along the dashed dotted line L1. In other words, the upper conveying path portion 732 is a wall portion provided above the upper first conveying path R14 along the upper first conveying path R14.

[0107] The switching gate 74 as an example of the guide member is a metal plate provided between the registration roll 52 and the transport roll 51 in the transport direction, and switches the transport path through which the paper P passes between the lower first transport path R13 and the upper first transport path R14. The switching gate 74 is provided extending linearly, and rotates in a clockwise direction and a counterclockwise direction around a rotation axis (not shown). More specifically, the switching gate 74 does not rotate when it receives a force less than a predetermined value in the rotation direction, and rotates when it receives a force equal to or greater than a predetermined value in the rotation direction. An example of the force equal to or greater than the predetermined value is a force acting on the switching gate 74 when the paper P as thick paper hits the switching gate 74. An example of the thick paper is a paper P having a basis weight threshold value and a thickness threshold value both of which are determined as control conditions. In the illustrated example, the switching gate 74 is provided opposite the lower transport path portion 731 across the lower first transport path R13, and is provided along the lower transport path portion 731.

[0108] 15 is a diagram showing an example in which thin paper P1 is conveyed to the registration rolls 52. Note that the thin paper P1 may be a sheet of paper P having a basis weight below a threshold value determined as a control condition and a thickness below a threshold value determined as a control condition. 15(A), as the thin paper P1 is transported by the registration roll 52, the leading edge on the downstream side in the transport direction hits the switching gate 74. In this case, the switching gate 74 is pushed by the thin paper P1, but does not rotate because the force it receives from the thin paper P1 is small.

[0109] In this case, as shown in FIG. 15B, the thin paper sheet P1 travels along the switching gate 74 and the lower transport path portion 731, and thus passes through the lower first transport path R13 while curving. Next, as the thin paper P1 is transported by the registration roll 52, the downstream leading end of the thin paper P1 in the transport direction reaches the transport roll 51, as shown in Fig. 15(C). At this time, slack is formed in the thin paper P1 in the transport direction between the registration roll 52 and the transport roll 51. More specifically, slack is formed in the thin paper P1 as the thin paper P1 is transported along the lower first transport path R13 while passing between the switching gate 74 and the lower transport path section 731. Next, as shown in FIG. 15(D), the transport control unit 105 causes the transport roll 51 to transport the thin paper sheet P1.

[0110] 16 is a diagram showing an example in which thick paper P2 is transported by transport rolls 51. As described above, the thick paper P2 may be a sheet of paper P having a basis weight greater than the threshold value defined as the control condition and a thickness greater than the threshold value defined as the control condition. As shown in FIG. 16A, when the thick sheet P2 is transported to the registration rolls 52, the leading edge of the thick sheet P2 on the downstream side in the transport direction abuts against the switching gate 74.

[0111] In this case, as shown in Fig. 16(B), the switching gate 74 is pushed by the thick sheet P2 to rotate counterclockwise and is provided along the upper first transport path R14. The thick sheet P2 also passes through the upper first transport path R14 without bending by moving along the switching gate 74 and the upper transport path section 732. Additionally, the thick sheet P2 is more rigid than the thin sheet P1 (see Fig. 15(B)), and therefore moves along the upper first transport path R14 without sagging. Furthermore, when the downstream leading edge of the thick sheet P2 in the transport direction reaches the transport roll 51, the transport control unit 105 causes the transport roll 51 to transport the thick sheet P2, as shown in FIG. 16(C).

[0112] As described above, the configuration for forming slack in the paper P to suppress the paper P from being pulled by the registration roll 52 may be realized not only by controlling the transport of the registration roll 52 and the transport of the transport roll 51, but also by the transport path section 73. In other words, the transport path section 73 forms slack in a portion of the paper P that is transported to the transport roll 51 and whose upstream tip in the transport direction has not passed through the nip portion N1, the portion being located between the transport roll 51 and the registration roll 52 in the transport direction. Even in this case, when the paper P is transported to the registration rolls 52, the portion of the paper P that overlaps with the cutter unit 58 in the transport direction is prevented from being pulled by the registration rolls 52.

[0113] Moreover, the transport path section 73 forms slack in the paper P, thereby suppressing the paper P transported by the registration roll 52 and the transport roll 51 from being pulled by the registration roll 52. Therefore, the transport path section 73 can also be regarded as a means for suppressing or preventing the portion of the paper P transported by the transport roll 51 and having its upstream tip in the transport direction not passing through the predetermined transport path, which overlaps with the cutter unit 58 in the transport direction, from being pulled by the registration roll 52.

[0114] In addition, the conveying path section 73 has a lower conveying path section 731 that is provided between the registration roll 52 and the conveying roll 51 in the conveying direction and forms a lower first conveying path R13 that is curved downward in the thickness direction of the paper P being conveyed. In this case, the degree of slack formed in the paper P passing through the lower first transport path R13 is suppressed compared to a configuration in which slack is formed in the paper P without the paper P passing through a transport path curved in the thickness direction.

[0115] The switching gate 74 guides the paper P of a predetermined type to the lower first transport path R13, and guides the paper P of a different type to the upper first transport path R14. An example of the paper P of a predetermined type is thin paper P1. An example of the paper P of a different type is thick paper P. In this case, the load on the thick paper P is reduced compared to a configuration in which the switching gate 74 guides the paper P to the lower first transport path R13 regardless of the type of paper P.

[0116] In the above example, the upper first transport path R14 is described as a transport path that is not curved in the thickness direction of the transported paper P, but is not limited to this. The upper first transport path R14 may be a transport path that is curved in the thickness direction of the transported paper P to a lesser extent than the lower first transport path R13. In other words, the upper first transport path R14 may be a transport path that is less curved in the thickness direction than the lower first transport path R13 or is not curved in the thickness direction at all.

[0117] In the above example, the lower transport path portion 731 is recessed downward. In this embodiment, the degree of downward depression in the lower transport path portion 731 is determined so that the slack formed in the paper sheet P satisfies the slack condition when the paper sheet P passes through the lower first transport path R13.

[0118] <Third embodiment> Next, the second post-processing device 4 of the third embodiment will be described. In the first and second embodiments, it has been described that the second post-processing device 4 forms slack in the paper P to prevent the portion of the paper P that overlaps with the cutter unit 58 in the transport direction from being pulled by the registration roll 52. Here, the configuration for preventing or suppressing the portion of the paper P that overlaps with the cutter unit 58 in the transport direction from being pulled by the registration roll 52 is not limited to that described in the first and second embodiments. With regard to the third embodiment, the configuration of the second post-processing device 4 that differs from the first or second embodiment will be mainly described, and descriptions of the same configuration as the second post-processing device 4 of the first or second embodiment may be omitted.

[0119] FIG. 17 is a diagram showing the state of the upstream transport roll 43 and the registration roll 52 when the paper P is transported to the transport roll 51. As shown in FIG. 17(A), the paper P is transported to the upstream transport roll 43 and the registration roll 52. The paper P has not yet reached the transport roll 51. At this time, a nip portion N4 of the upstream transport roll 43 and a nip portion N1 of the registration roll 52 are formed. The nip portion N4 of the upstream transport roll 43 is a portion sandwiched between the upstream driving roll 431 and the upstream driven roll 432.

[0120] Next, when the downstream leading end of the paper P in the transport direction reaches the nip portion N2 of the transport roll 51 while the paper P is being transported by the upstream transport roll 43 and the registration roll 52, the transport roll 51 starts transporting the paper P. At this time, as shown in FIG. 17B, the upstream driven roll 432 retreats from the upstream driving roll 431 and the registration driven roll 522 retreats from the registration driving roll 521, so that the nip portion N4 and the nip portion N1 are not formed. In this embodiment, the transport control unit 105 controls the movement of the rotation shaft (not shown) of the upstream driven roll 432 so as to retreat from the upstream driving roll 431, so that the upstream driven roll 432 retreats from the upstream driving roll 431. Moreover, the conveyance control unit 105 controls the movement of the rotation shaft (not shown) of the registration driven roll 522 so as to retreat from the registration driving roll 521, whereby the registration driven roll 522 retreats from the registration driving roll 521. The retreat of the rotation shaft (not shown) of the upstream side driven roll 432 and the rotation shaft (not shown) of the registration driven roll 522 is realized by, for example, releasing the pressure applied by a pressing member (not shown) that presses the rotation shaft (not shown) of the upstream side driven roll 432 and the rotation shaft (not shown) of the registration driven roll 522.

[0121] When the upstream driven roll 432 retreats from the upstream driving roll 431, the pressure of the upstream driven roll 432 against the upstream driving roll 431 is released. When the registration driven roll 522 retreats from the registration driving roll 521, the pressure of the registration driven roll 522 against the registration driving roll 521 is released. In this case, the paper P is transported only by the transport roll 51. More specifically, even if the paper P overlaps with the upstream transport roll 43 and the registration roll 52 in the transport direction, the paper P is transported to the transport roll 51 without being transported by the upstream transport roll 43 and the registration roll 52.

[0122] 17(C), when the transport of the paper P by the transport roll 51 progresses, the upstream leading end of the paper P in the transport direction reaches a position downstream in the transport direction of the upstream transport roll 43 and the registration roll 52. At this time, the upstream driven roll 432 continues to retract from the upstream driving roll 431, and the registration driven roll 522 continues to retract from the registration driving roll 521.

[0123] Next, when the transport of the paper P by the transport roll 51 proceeds further, as shown in FIG. 17(D), the upstream leading end of the paper P in the transport direction reaches the downstream side of the nip portion N2 of the transport roll 51 in the transport direction. Then, when the paper P reaches the downstream side of the transport roll 51 in the transport direction, the transport control unit 105 advances the upstream driven roll 432 toward the upstream driving roll 431 and advances the registration driven roll 522 toward the registration driving roll 521. In this case, the upstream driven roll 432 is pressed against the upstream driving roll 431 again, and the registration driven roll 522 is pressed against the registration driving roll 521, so that the nip portion N4 and the nip portion N1 are formed again. Although not shown, the paper P is transported to the first downstream transport roll 44 (see FIG. 2) or the second downstream transport roll 45 at this time.

[0124] 18 is a flow chart showing the flow of the pressure release process. The pressure release process is a process in which the transport control unit 105 releases the pressure of the upstream driven roll 432 against the upstream driving roll 431 and the pressure of the registration driven roll 522 against the registration driving roll 521. In this embodiment, the pressure release process is started when an instruction is given to cut the paper P by the cutting device 50. When the paper sheet P reaches the upstream transport rolls 43, the transport control unit 105 starts transport of the paper sheet P by the upstream transport rolls 43 (S301).

[0125] When the sheet P reaches the registration rolls 52, the conveyance control unit 105 starts conveying the sheet P by the registration rolls 52 (S302). The conveyance control unit 105 judges whether or not the release condition is satisfied (S303). The release condition is a condition determined so that the conveyance control unit 105 can release the pressure of the upstream driven roll 432 against the upstream driving roll 431 and the pressure of the registration driven roll 522 against the registration driving roll 521. In this embodiment, the release condition is determined as the start of conveyance of the paper P by the conveyance roll 51. The conveyance control unit 105 specifies the current position of the paper P from the relationship between the position of the paper P indicated in the conveyance information acquired by the conveyance information acquisition unit 104 and the conveyance speed of the registration roll 52, and judges whether or not conveyance of the paper P by the conveyance roll 51 has been started from the specified position of the paper P. While the negative result continues (NO in S303), the process of S303 is repeated.

[0126] If the release condition is met (YES in S303), the process proceeds to the next step. The transport control unit 105 retracts the upstream driven roll 432 and the registration driven roll 522 to release the pressure of the upstream driven roll 432 against the upstream driving roll 431 and the pressure of the registration driven roll 522 against the registration driving roll 521 (S304).

[0127] The conveyance control unit 105 judges whether the conveyance condition is satisfied (S305). The conveyance condition is a condition determined so that the conveyance control unit 105 causes the upstream driven roll 432 to press the upstream driving roll 431 again and causes the registration driven roll 522 to press the registration driving roll 521. The conveyance condition is determined from the viewpoint of preventing the paper P from being pulled by the upstream conveyance roll 43 or the registration roll 52 and the conveyance roll 51. In this embodiment, the conveyance condition is determined so that the upstream leading edge of the paper P in the conveyance direction reaches the downstream side in the conveyance direction of the nip portion N2 (see FIG. 17(D)) of the conveyance roll 51. While the negative result continues (NO in S305), the process of S305 is repeated.

[0128] If the transport conditions are met (YES in S305), the process proceeds to the next step. The conveying control unit 105 advances the upstream driven roll 432 and the resist driven roll 522, thereby causing the upstream driven roll 432 to press against the upstream driving roll 431 again and causing the resist driven roll 522 to press against the resist driving roll 521 (S306).

[0129] In this embodiment, the release condition is that the transport of the paper P by the transport rolls 51 starts, but the present invention is not limited to this. The release condition may be that the leading edge of the paper P on the upstream side in the transport direction reaches the nip portion N2 of the transport rolls 51. When the release condition is satisfied, the transport control unit 105 may release the pressure applied by the upstream driven roll 432 and the registration driven roll 522 before the transport of the paper P by the transport rolls 51 starts.

[0130] In addition, in the present embodiment, the transport condition is that the leading edge of the paper P on the upstream side in the transport direction reaches the downstream side in the transport direction of the nip portion N2 of the transport roll 51, but the transport condition is not limited to this. The transport condition may be that the upstream side of the paper P in the transport direction reaches the downstream side in the transport direction of the nip portion N1 of the registration roll 52. In other words, the transport condition may be satisfied when the paper P is being transported by the transport roll 51.

[0131] Also, different transport conditions may be set for the upstream transport roll 43 and the registration roll 52. An example of the transport condition for the upstream transport roll 43 is that the upstream tip end of the paper P in the transport direction reaches a position downstream of the upstream transport roll 43 in the transport direction. An example of the transport condition for the registration roll 52 is that the upstream side of the paper P in the transport direction reaches a position downstream of the nip portion N1 of the registration roll 52 in the transport direction.

[0132] In addition, in this embodiment, when the release condition is satisfied, the conveying control unit 105 retracts the upstream driven roll 432 from the upstream driving roll 431 and retracts the resist driven roll 522 from the resist driving roll 521, but this is not limited to this. When the release condition is satisfied, the conveyance control unit 105 may displace the upstream driven roll 432 and the resist driven roll 522 so that the pressing of the upstream drive roll 431 by the upstream driven roll 432 and the pressing of the resist drive roll 521 by the resist driven roll 522 are suppressed compared to before the release condition is satisfied. In this case, the upstream driven roll 432 may not be retracted from the upstream drive roll 431, and the resist driven roll 522 may not be retracted from the resist drive roll 521.

[0133] As described above, when the paper P is being transported by the transport rolls 51, the transport control unit 105 suppresses or prevents the paper P from being pulled by the registration rolls 52. In other words, the CPU 211 suppresses or prevents the portion of the paper P that is transported by the transport rolls 51 and whose leading edge on the upstream side in the transport direction has not passed through the predetermined transport path, which overlaps with the cutter unit 58 in the transport direction, from being pulled by the registration rolls 52.

[0134] Further, the conveyance control unit 105 controls the registration driven roll 522 to be displaced to the side opposite to the registration driving roll 521. In other words, the CPU 211 is a processor that suppresses or cancels the pressing of the registration driven roll 522 against the registration driving roll 521. In this case, compared to a configuration in which the registration driven roll 522 continues to press the registration drive roll 521, the portion of the paper P that overlaps with the cutter unit 58 in the conveying direction is suppressed or prevented from being pulled by the registration roll 52.

[0135] In the present embodiment, the conveyance control unit 105 suppresses or releases the pressing of the registration driven roll 522 against the registration driving roll 521 at least from the start of conveyance of the paper P by the conveyance roll 51 until the conveyance condition is satisfied. The conveyance condition can also be regarded as a condition determined in advance for the conveyance of the paper P. In this case, compared to a configuration in which the pressure of the resist drive roll 521 by the resist driven roll 522 is not suppressed before predetermined conditions for the transportation of the paper P are satisfied, the portion of the paper P that overlaps with the cutter unit 58 in the transport direction is suppressed or prevented from being pulled by the resist roll 52.

[0136] 18 may be performed depending on whether the control conditions are satisfied. That is, when an instruction to cut the paper P by the cutting device 50 is given, the pressure release process may be performed if any of the control conditions are satisfied, and the pressure release process may not be performed if none of the control conditions are satisfied. Also, when the pressure release process is not performed, the pressure of the upstream driven roll 432 against the upstream driving roll 431 and the pressure of the registration driven roll 522 against the registration driving roll 521 are not released regardless of the state of the transport of the paper P. In addition, when none of the control conditions are satisfied, a pressure release process may be performed so that the pressing force of the upstream driven roll 432 on the upstream driving roll 431 and the pressing force of the resist driven roll 522 on the resist driving roll 521 when the release condition is satisfied and the transport condition is not satisfied are greater than when any of the control conditions are satisfied.

[0137] <Fourth embodiment> Next, the second post-processing device 4 of the fourth embodiment will be described. The second post-processing device 4 of the fourth embodiment differs from the second post-processing device 4 of the first to third embodiments in the configuration for suppressing or preventing the portion of the paper P that overlaps with the cutter unit 58 in the transport direction from being pulled by the registration roll 52. With regard to the fourth embodiment, the configuration of the second post-processing device 4 that differs from the first to third embodiments will be mainly described, and descriptions of the same configuration as the second post-processing device 4 of the first to third embodiments may be omitted.

[0138] FIG. 19 is a diagram showing the configuration of a registration roll 52 according to the fourth embodiment. As shown in Figure 19 (A), the registration roll 52 of this embodiment is provided with a registration drive roll 521, a registration driven roll 522, a drive rotation shaft 523, a driven rotation shaft 524, a chute 525, a coil spring 526, and a limiting member 527. The left-right direction shown in FIG. 19(A) corresponds to the left-right direction shown in FIG.

[0139] The resist drive roll 521 includes a first resist drive roll 5211 , a second resist drive roll 5212 , a third resist drive roll 5213 , and a fourth resist drive roll 5214 . The first resist drive roll 5211, the second resist drive roll 5212, the third resist drive roll 5213, and the fourth resist drive roll 5214 are arranged side by side in the left-right direction. In the illustrated example, the first resist drive roll 5211, the second resist drive roll 5212, the third resist drive roll 5213, and the fourth resist drive roll 5214 are arranged in this order from the right side of the resist roll 52.

[0140] The resist driven roll 522 includes a first resist driven roll 5221, a second resist driven roll 5222, a third resist driven roll 5223, and a fourth resist driven roll 5224. The first registration driven roll 5221, the second registration driven roll 5222, the third registration driven roll 5223, and the fourth registration driven roll 5224 are arranged side by side in the left-right direction. In the illustrated example, the first registration driven roll 5221, the second registration driven roll 5222, the third registration driven roll 5223, and the fourth registration driven roll 5224 are arranged in this order from the right side of the registration roll 52. In addition, the first registration driven roll 5221, the second registration driven roll 5222, the third registration driven roll 5223, and the fourth registration driven roll 5224 are arranged opposite the first registration driving roll 5211, the second registration driving roll 5212, the third registration driving roll 5213, and the fourth registration driving roll 5214 via the transport path.

[0141] The second resist driving roll 5212 and the second resist driven roll 5222, and the third resist driving roll 5213 and the third resist driven roll 5223 are all regarded as a first second transport means. In addition, the first resist driving roll 5211 and the first resist driven roll 5221, and the fourth resist driving roll 5214 and the fourth resist driven roll 5224 are all regarded as a second second transport means that is provided outside the first second transport means in the width direction.

[0142] The drive rotation shaft 523 is a rotation shaft of the resist drive roll 521. More specifically, the drive rotation shaft 523 is a rotation shaft of the first resist drive roll 5211, the second resist drive roll 5212, the third resist drive roll 5213, and the fourth resist drive roll 5214. The position of the drive rotation shaft 523 is fixed in the cutting device 50. The driven rotation shaft 524 is a rotation shaft of the registration driven roll 522. The driven rotation shaft 524 is provided with a right driven rotation shaft 5241 which is a rotation shaft of the first registration driven roll 5221 and the second registration driven roll 5222, and a left driven rotation shaft 5242 which is a rotation shaft of the third registration driven roll 5223 and the fourth registration driven roll 5224. Both the right driven rotation shaft 5241 and the left driven rotation shaft 5242 can be displaced in the up and down direction.

[0143] The chute 525 is a plate-like member extending along the transport direction and guiding the paper P. The chute 525 is provided from the right side of the first registration driven roll 5221 to the left side of the fourth registration driven roll 5224 in the left-right direction, and is also provided from the upstream side to the downstream side of the registration driven roll 522 in the transport direction. The chute 525 includes an upper chute 5251 provided above the transport path, and a lower chute 5252 provided below the transport path.

[0144] The coil spring 526 is a spring having elasticity. One end and the other end of the coil spring 526 are attached to the upper chute 5251, and a portion between the one end and the other end is provided so as to press the driven rotating shaft 524 from above, and presses the driven rotating shaft 524 downward. The coil spring 526 is provided with a first coil spring 5261, a second coil spring 5262, a third coil spring 5263, and a fourth coil spring 5264. In the illustrated example, the first coil spring 5261, the second coil spring 5262, the third coil spring 5263, and the fourth coil spring 5264 are provided in this order from the right side of the registration roll 52. The first coil spring 5261 is provided so as to press the right end of the right driven rotation shaft 5241 , and the second coil spring 5262 is provided so as to press the left end of the right driven rotation shaft 5241 . The third coil spring 5263 is provided so as to press the right end of the left driven rotation shaft 5242 , and the fourth coil spring 5264 is provided so as to press the left end of the left driven rotation shaft 5242 .

[0145] The limiting member 527 is a member that limits the pressure applied to the driven rotation shaft 524 by the coil spring 526. The limiting member 527 includes a pin 5271 and two plate-shaped members 5272. Pin 5271 is a columnar member extending in the left-right direction from a position overlapping first coil spring 5261 to a position overlapping fourth coil spring 5264. Pin 5271 rotates by receiving a driving force from a motor (not shown). Plate-shaped member 5272 is formed in a plate shape, with one end attached to pin 5271 and the other end attached to coil spring 526. Of the two plate-shaped members 5272, the first plate-shaped member 5272 is attached to first coil spring 5261, and the second plate-shaped member 5272, although not shown, is attached to fourth coil spring 5264. In other words, plate-shaped member 5272 is not attached to second coil spring 5262 and third coil spring 5263.

[0146] In the above-mentioned registration roll 52, when the paper P is not transported to the registration roll 52, the plate-shaped member 5272 is inclined as shown in FIG. 19(B). More specifically, the plate-shaped member 5272 is inclined so that the tip of the plate-shaped member 5272 attached to the first coil spring 5261 is located below the tip of the plate-shaped member 5272 attached to the pin 5271. At this time, the right driven rotation shaft 5241 is pressed by the first coil spring 5261, so that the first registration driven roll 5221 presses the first registration driving roll 5211 with a force F1. Then, when the paper P reaches the registration roll 52, the paper P hits the nip portion N1 in the state of the registration roll 52 shown in FIG. 19(B). This corrects the inclination of the paper P with respect to the transport direction.

[0147] Also, when the paper P is being transported to the registration roll 52, the transport control unit 105 controls the motor (not shown) so that the pin 5271 rotates counterclockwise when the pin 5271 is viewed from the right side of the pin 5271, as shown in FIG. 19(C). In this case, the tip of the plate member 5272 attached to the first coil spring 5261 moves upward. Also, when the tip of the plate member 5272 moves upward, the first coil spring 5261 is biased upward, so that the pressing of the right driven rotation shaft 5241 by the first coil spring 5261 is relaxed, and accordingly, the pressing of the first registration drive roll 5211 by the first registration driven roll 5221 is suppressed. More specifically, the first registration driven roll 5221 presses the first registration drive roll 5211 with a force F2 smaller than the force F1. In other words, the pressure at the nip portion N1 is lower when the paper P is being transported to the registration rolls 52 than when the paper P is not being transported to the registration rolls 52. The pressure at the nip portion N1 is the pressing force of the first registration driven roll 5221 against the first registration driving roll 5211.

[0148] 19B and 19C, the relationship between the first coil spring 5261, the first registration driving roll 5211, and the first registration driven roll 5221 has been described. Here, the relationship between the fourth coil spring 5264, the fourth registration driving roll 5214, and the fourth registration driven roll 5224 is the same as the relationship between the first coil spring 5261, the first registration driving roll 5211, and the first registration driven roll 5221. In other words, when the paper P is being transported to the registration roll 52, the limiting member 527 operates to suppress the pressing of the fourth registration driven roll 5224 against the fourth registration driving roll 5214, compared to when the paper P is not being transported to the registration roll 52.

[0149] On the other hand, since the plate-shaped member 5272 is not attached to the second coil spring 5262 and the third coil spring 5263, even if the limiting member 527 operates, the second coil spring 5262 and the third coil spring 5263 are not biased against the plate-shaped member 5272. Therefore, even when the paper P is being transported to the registration rolls 52, the pressing of the second registration drive roll 5212 by the second registration driven roll 5222 and the pressing of the third registration drive roll 5213 by the third registration driven roll 5223 are not suppressed. In this case, when the paper P is transported to the registration roll 52, the transport of the paper P by the registration roll 52 is more stable than in a configuration in which the pressure of the registration drive roll 521 by any of the registration driven rolls 522 is suppressed.

[0150] Thus, in this embodiment, when the paper P is transported to the registration roll 52, the pressing of the first registration driven roll 5221 against the first registration drive roll 5211 and the pressing of the fourth registration driven roll 5224 against the fourth registration drive roll 5214 are suppressed. In this case, when the paper P is transported by the registration rolls 52 and the transport rolls 51, the pulling of the left-right ends of the paper P by the registration rolls 52 is alleviated. Therefore, compared to a configuration in which the paper P transported by the transport rolls 51 is not suppressed from being pulled by the registration rolls 52, the displacement of both ends in the left-right direction of the paper P toward the center is suppressed by the amount that the pulling of the paper P is alleviated. Therefore, the occurrence of variation in the portion of the paper P cut by the cutter unit 58 is suppressed.

[0151] 20 is a flowchart showing the flow of the operation process. The operation process is a process in which the conveyance control unit 105 operates the limiting member 527. In this embodiment, the operation process is started when an instruction is given to cut the paper P by the cutting device 50. The conveyance control unit 105 judges whether or not the rotation condition is satisfied (S401). The rotation condition is a condition determined so that the conveyance control unit 105 rotates the pin 5271 of the limiting member 527. In this embodiment, the rotation condition is determined as the start of conveyance of the paper P by the registration roll 52. The conveyance control unit 105 identifies the current position of the paper P from the position of the paper P indicated in the conveyance information acquired by the conveyance information acquisition unit 104, and judges whether or not conveyance of the paper P by the registration roll 52 has started from the identified position of the paper P. While the negative result continues (NO in S401), the process of S401 is repeated. Also, at the time when S401 is being performed, the plate-shaped member 5272 of the limiting member 527 is provided at the position shown in FIG. 19(B).

[0152] When the rotation condition is satisfied (YES in S401), the transport control unit 105 controls the pin 5271 to rotate counterclockwise when viewed from the right side of the pin 5271 of the limiting member 527 (S402). In this case, the plate-shaped member 5272 moves to the position shown in FIG. 19(C). The transport control unit 105 determines whether the leading edge of the paper P on the upstream side in the transport direction has passed the registration roll 52 (S403). The transport control unit 105 identifies the current position of the paper P from the relationship between the position of the paper P indicated in the transport information acquired by the transport information acquisition unit 104 and the transport speed of the registration roll 52. Then, from the identified position of the paper P, it determines whether the leading edge of the paper P on the upstream side in the transport direction has reached the downstream side in the transport direction of the registration roll 52. While a negative result continues (NO in S403), the process of S403 is repeated.

[0153] When the paper P has passed the registration roll 52 (YES in S403), the conveyance control unit 105 controls the pin 5271 of the limiting member 527 to rotate in a clockwise direction when the pin 5271 is viewed from the right side of the pin 5271 (S404). In this case, the plate member 5272 returns to the position shown in FIG. 19(B) again. The timing when the paper P passes the registration rolls 52 is after the paper P starts to be transported by the transport rolls 51. More specifically, the timing when the upstream leading edge of the paper P in the transport direction reaches the downstream side of the registration rolls 52 in the transport direction is after the paper P starts to be transported by the transport rolls 51 and before the upstream leading edge of the paper P in the transport direction reaches the downstream side of the transport rolls 51 in the transport direction.

[0154] In the above example, the rotation condition is that the registration rolls 52 start transporting the paper P, but the present invention is not limited to this. The rotation condition may be that the leading edge of the paper P on the downstream side in the transport direction hits the registration roll 52. When the rotation condition is satisfied, the transport control unit 105 may rotate the pin 5271 even before the transport of the paper P by the registration roll 52 starts.

[0155] As described above, when the paper P is transported by the registration rolls 52 and the transport rolls 51, the transport control unit 105 suppresses the pressing of the registration drive roll 521 by the registration driven roll 522, thereby suppressing the paper P from being pulled by the registration rolls 52. In other words, the CPU 211 suppresses the portion of the paper P that is transported by the transport rolls 51 and whose leading edge on the upstream side in the transport direction has not passed through the nip portion N2, which overlaps with the cutter unit 58 in the transport direction, from being pulled by the registration rolls 52.

[0156] In addition, the CPU 211 can also be seen as a means for suppressing or preventing the portion of the paper P that is transported by the transport roll 51 and whose upstream leading edge in the transport direction has not passed the nip portion N2, which overlaps with the cutter unit 58 in the transport direction, from being pulled by the registration roll 52.

[0157] Furthermore, when the paper P is being transported by the first registration driving roll 5211 and the first registration driven roll 5221, the transport control unit 105 suppresses the pressing of the first registration driving roll 5211 by the first registration driven roll 5221. In this case, compared to a configuration in which the pressing of the first registration drive roll 5211 by the first registration driven roll 5221 is not suppressed, when the paper P is transported by the registration roll 52 and the transport roll 51, the pulling of the left-right ends of the paper P by the registration roll 52 is alleviated. Therefore, compared to a configuration in which the pulling of the paper P transported by the transport roll 51 by the registration roll 52 is not suppressed, the displacement of both ends in the left-right direction of the paper P toward the center is suppressed by the amount that the pulling of the paper P is alleviated.

[0158] In addition, the conveying control unit 105 does not suppress the pressing of the first resist driven roll 5221 against the first resist driving roll 5211 until the paper P comes into contact with the registration roll 52, and suppresses the pressing of the first resist driven roll 5221 against the first resist driving roll 5211 when the conveyance of the paper P by the registration roll 52 begins. When the pressing of the first registration driving roll 5211 by the first registration driven roll 5221 is suppressed before the paper P contacts the registration roll 52, the paper P is less likely to strike the nip portion N1. Also, when the paper P does not strike the nip portion N1, the inclination of the paper P with respect to the conveying direction is less likely to be corrected even if the paper P contacts the registration roll 52. In contrast, as in this embodiment, when the pressing of the first registration driving roll 5211 by the first registration driven roll 5221 is not suppressed until the paper P contacts the registration roll 52, the inclination of the paper P with respect to the conveying direction is suppressed by the amount that the paper P is more likely to strike the nip portion N1 compared to a configuration in which the pressing of the first registration driving roll 5211 by the first registration driven roll 5221 is suppressed before the paper P contacts the registration roll 52.

[0159] 20 may be performed depending on whether the control conditions are satisfied. That is, when an instruction to cut the paper P by the cutting device 50 is given, the operation process may be performed if any of the control conditions are satisfied, and the operation process may not be performed if none of the control conditions are satisfied. In addition, when the operation process is not performed, even when the paper P is being transported to the registration roll 52, the plate-like member 5272 may continue to be provided at the position shown in FIG. 19(B), so that the pressing of the registration drive roll 521 by any of the registration driven rolls 522 is not suppressed. Furthermore, when none of the control conditions are satisfied, the conveyance control unit 105 may reduce the counterclockwise rotation angle of the pin 5271 in S402 of the operation process compared to when any of the control conditions are satisfied. In other words, when none of the control conditions are satisfied, the operation process may be performed so that the pressing force of the rotating member by the opposing member in the second second conveying means before the rotation condition is satisfied and the paper P passes the registration roll 52 is larger than when any of the control conditions are satisfied.

[0160] FIG. 21 is a flowchart showing the flow of processing performed by the CPU 211. The CPU 211 executes a program to realize each process shown in FIG. The CPU 211 controls the motor to transport the paper P by the registration roll 52 (S501). The function of the CPU 211 to cause the registration roll 52 to transport the paper P is regarded as a second transport function.

[0161] The CPU 211 suppresses or prevents the pulling of the paper P by the registration roll 52 (S502). The function of suppressing or preventing the pulling of the paper P by the registration roll 52 is realized by forming slack in the paper P shown in Figs. 7 and 8, or by suppressing or releasing the pressing of the registration drive roll 521 by the registration driven roll 522 shown in Figs. 17 and 19.

[0162] The CPU 211 controls the motor to transport the paper P by the transport roll 51 (S503). The function of the CPU 211 to cause the transport roll 51 to transport the paper P is regarded as a first transport function. The CPU 211 causes the cutter unit 58 to cut the paper P being transported by the transport rolls 51 along the transport direction (S504). More specifically, the CPU 211 causes the transport rolls 51 to transport the paper P while the paper P is sandwiched between the cutter unit 58, thereby realizing cutting of the paper P along the transport direction. The function of the CPU 211 causing the cutter unit 58 to cut the paper P can also be regarded as a cutting function.

[0163] The timing of performing S502 is not limited to the order shown in the figure. S502 may be performed simultaneously with S501, or may be performed simultaneously with S503 or S504. Furthermore, the timing at which S503 and S504 are performed is not limited to the order shown in the figure, and S503 and S504 may be performed simultaneously.

[0164] As described above, the program executed by CPU 211 realizes the function of suppressing or preventing the portion of paper P that is being transported by the first transport function and whose upstream leading edge in the transport direction has not passed through a predetermined transport path, which overlaps in the transport direction with the portion to be cut by the cutting function, from being pulled by transport by the second transport function. In this case, displacement of both ends of the paper P in the left-right direction toward the center is suppressed compared to a configuration in which the paper P being transported by the first transport function is not suppressed from being pulled by transport by the second transport function.

[0165] In the above example, the first transport means is the transport roll 51, but the present invention is not limited to this. A transport belt that is stretched around a plurality of transport rolls including the transport roll 51 and transports the paper P may be provided for each transport roll 51. In other words, the first transport means may be a transport belt.

[0166] In the above example, the second transport means is the registration roll 52, but the present invention is not limited to this. The second transport means may be a transport belt that is stretched around a plurality of transport rolls including the registration roll 52 and transports the paper P.

[0167] In the above example, the cutter unit 58 is provided at a position overlapping with the outer transport roll 51 and the end transport roll 51 in the transport direction, but the present invention is not limited to this. The cutter unit 58 may be provided upstream or downstream in the transport direction from the outer transport roll 51 or the end transport roll 51, as long as the cutter unit 58 cuts the paper P being transported by the outer transport roll 51 or the end transport roll 51 along the transport direction.

[0168] In the above example, the switching gate 72 and the switching gate 74 are both described as being made of metal plates having a rotation axis, but the present invention is not limited to this. The switching gate 72 and the switching gate 74 may be made of a resin material such as Mylar.

[0169] In addition, in the above-mentioned example, the outer drive roll 511 to the left of the central transport roll 51 and the end drive roll 511, and the outer drive roll 511 to the right of the central transport roll 51 and the end drive roll 511 are mounted on the same rotating shaft, but this is not limited to this. The outer drive roll 511 on the left side of the central transport roll 51 and the end drive roll 511, and the outer drive roll 511 on the right side of the central transport roll 51 and the end drive roll 511 may be provided on different rotation axes.

[0170] In addition, in the above-mentioned example, the outer driven roll 512 to the left of the central transport roll 51 and the end driven roll 512, and the outer driven roll 512 to the right of the central transport roll 51 and the end driven roll 512 are mounted on the same rotating shaft, but this is not limited to this. The outer driven roll 512 to the left of the central transport roll 51 and the end driven roll 512, and the outer driven roll 512 to the right of the central transport roll 51 and the end driven roll 512 may be provided on different rotation axes.

[0171] In the above example, the second post-processing device 4 is provided downstream of the first post-processing device 3 in the transport direction, but the present invention is not limited to this. The second post-processing device 4 may be provided upstream in the transport direction from the first post-processing device 3. In particular, when the second post-processing device 4 is configured to cut the top and bottom of each sheet P as it is transported, rather than cutting a sheet bundle made up of multiple sheets P, the second post-processing device 4 is provided upstream in the transport direction from the first post-processing device 3.

[0172] Although the embodiment of the present invention has been described above, the technical scope of the present invention is not limited to the scope described in the above embodiment. It is clear from the description of the claims that various modifications and improvements to the above embodiment are also included in the technical scope of the present invention. Further, although multiple embodiments have been described above, the configurations included in one embodiment may be interchanged with the configurations included in other embodiments, or the configurations included in one embodiment may be added to other embodiments.

[0173] (Additional Note) (((1))) A first conveying means for conveying a recording medium; a cutting member arranged next to the first conveying means in a width direction of the recording medium being conveyed, the cutting member cutting the recording medium along a conveying direction of the recording medium; a second conveying means provided upstream of the first conveying means in the conveying direction and configured to convey the recording medium that has reached a predetermined conveying path; a means for suppressing or preventing a portion of the recording medium, which is conveyed by the first conveying means and whose leading edge on the upstream side in the conveying direction has not passed through the predetermined conveying path, overlapping with the cutting member in the conveying direction from being pulled by the second conveying means; A recording medium processing device comprising: (((2))) The recording medium processing device described in (((1))), wherein the suppressing or preventing means is a forming means for forming slack in a portion of the recording medium that is transported by the first transport means and whose upstream leading edge in the transport direction has not passed the predetermined transport path, the portion being positioned between the first transport means and the second transport means in the transport direction. (((3))) the forming means is a processor that controls a conveying speed of the recording medium by the first conveying means and / or a conveying speed of the recording medium by the second conveying means; The recording medium processing device according to (((2))), wherein the processor controls the conveying speed of the second conveying means to be faster than the conveying speed of the first conveying means. (((4))) a third conveying means provided downstream of the first conveying means in the conveying direction; a forming member provided between the first conveying means and the third conveying means in the conveying direction, the forming member forming a conveying path curved to one side in a thickness direction of the recording medium being conveyed; Further equipped with The recording medium processing device according to (((3))), wherein the processor controls the conveying speed of the third conveying means to be faster than the conveying speed of the first conveying means. (((5))) a guide member for guiding the recording medium conveyed by the first conveying means to the conveying path, the conveying path includes an overlapping conveying path that overlaps with the curved conveying path in the conveying direction and is less curved in the thickness direction than the curved conveying path or is not curved in the thickness direction; The recording medium processing device described in (((4))), wherein the guide member guides the recording medium of a predetermined type to the curved transport path and guides the recording medium of a different type to the overlapping transport path. (((6))) the forming means is a processor that controls the conveyance of the recording medium by the first conveying means and the conveyance of the recording medium by the second conveying means; The recording medium processing device described in (((2))) wherein, when the recording medium being transported by the second transport means reaches the first transport means, the processor sets a period during which the first transport means does not transport the recording medium and the second transport means transports the recording medium. (((7))) The recording medium processing device described in (((2))), wherein the forming means is provided between the second conveying means and the first conveying means in the conveying direction and has a forming member that forms a conveying path curved on one side in the thickness direction of the recording medium being conveyed. (((8))) The forming means further includes a guide member that guides the recording medium conveyed by the second conveying means to the conveying path, the conveying path includes an overlapping conveying path that overlaps with the curved conveying path in the conveying direction and is less curved in the thickness direction than the curved conveying path or is not curved in the thickness direction; The recording medium processing device described in (((7))), wherein the guide member guides the recording medium of a predetermined type to the curved transport path and guides the recording medium of a different type to the overlapping transport path. (((9))) The recording medium processing device according to any one of ((2))) to (((8))), wherein the forming means forms the slack in the recording medium to a degree that satisfies a predetermined condition. (((10))) the second conveying means includes a rotating member and an opposing member that faces the rotating member via a conveying path of the recording medium and presses the rotating member; The recording medium processing device according to (((1))), wherein the suppressing or preventing means is a processor that suppresses or releases the pressing of the rotating member by the opposing member. (((11))) The recording medium processing device described in (((10))), wherein the processor suppresses or releases the pressing of the rotating member by the opposing member at least from the start of transport of the recording medium by the first transport means until a predetermined condition for the transport of the recording medium is satisfied. (((12))) The second conveying means includes at least a first second conveying means and a second second conveying means provided on the outer side of the first second conveying means in the width direction, The cutting member is provided on the outer side of the first conveying means in the width direction, The recording medium processing device according to (((10))), wherein the processor suppresses the pressing of the rotating member by the opposing member in the second second transport means when the recording medium is transported by the first second transport means. (((13))) The recording medium processing device described in (((12))) wherein the processor does not suppress the pressing of the rotating member by the opposing member in the second second conveying means until the recording medium comes into contact with the second conveying means, and suppresses the pressing when the second conveying means begins to convey the recording medium. (((14))) The recording medium processing device described in any one of (((1))) to (((13))), further comprising a pressing member that is provided outside the cutting member in the width direction and presses the recording medium that has been cut by the cutting member to form a fold in the recording medium along the transport direction. (((15))) An image forming system comprising an image forming device that forms an image on a recording medium, and a recording medium processing device that processes the recording medium on which the image has been formed by the image forming device, the recording medium processing device being configured to include any of the recording medium processing devices described in (((1))) to (((14))). (((16))) On the computer, A first conveying function for conveying a recording medium; a cutting function that cuts the recording medium being conveyed by the first conveying function along a conveying direction of the recording medium; a second conveying function for conveying the recording medium that has reached a predetermined conveying path upstream in a conveying direction of the recording medium from the conveying direction of the recording medium by the first conveying function; a function of suppressing or preventing a portion of the recording medium, which is conveyed by the first conveying function and whose leading end on the upstream side in the conveying direction has not passed through the predetermined conveying path, overlapping with a portion to be cut by the cutting function in the conveying direction from being pulled by the conveying function in the conveying direction; A program to achieve this.

[0174] According to the recording medium processing device of (((1))), it is possible to suppress displacement of the recording medium in the width direction, compared to a configuration in which the recording medium being transported by the first transport means is not suppressed from being pulled by the second transport means. According to the recording medium processing device of (((2))), even when the recording medium is being transported by the second transport means, it is possible to prevent the portion of the recording medium that overlaps with the cutting member in the transport direction from being pulled by the second transport means. According to the recording medium processing device of (((3))), it is no longer necessary to press the recording medium in the thickness direction of the recording medium in order to form slack in the recording medium. According to the recording medium processing device of (((4))), the occurrence of wrinkles in the recording medium can be suppressed compared to a configuration in which the recording medium is transported along a linear transport path from the first transport means to the third transport means. According to the recording medium processing device of (((5))), the load on recording media that are not of a predetermined type can be reduced, compared to a configuration in which a guide member guides the recording medium into a curved transport path regardless of the type of recording medium. According to the recording medium processing device of (((6))), it is no longer necessary to press the recording medium in the thickness direction of the recording medium in order to form slack in the recording medium. According to the recording medium processing device of (((7))), it is possible to suppress variation in the degree of slack formed in the recording medium passing through a curved transport path, compared to a configuration in which slack is formed in the recording medium without the recording medium passing through a transport path curved in the thickness direction. According to the recording medium processing device of (((8))), the load on recording media that are not of a predetermined type can be reduced, compared to a configuration in which a guide member guides the recording medium into a curved transport path regardless of the type of recording medium. According to the recording medium processing device of (((9))), it is possible to suppress a decrease in the accuracy of recording medium transport compared to a configuration in which slack is formed in the recording medium regardless of whether or not predetermined conditions are satisfied. According to the recording medium processing device of (((10))), compared to a configuration in which the opposing member continues to press the rotating member, it is possible to suppress or prevent the portion of the recording medium that overlaps with the cutting member in the conveying direction from being pulled by the second conveying means. According to the recording medium processing device of (((11))), it is possible to suppress or prevent the portion of the recording medium that overlaps with the cutting member in the conveying direction from being pulled by the second conveying means, compared to a configuration in which the pressing of the rotating member by the opposing member is not suppressed before a predetermined condition for the conveying of the recording medium is satisfied. According to the recording medium processing device of (((12))), it is possible to suppress displacement of the recording medium in the width direction, compared to a configuration in which the pressing of the rotating member by the opposing member in the second second conveying means is not suppressed. According to the recording medium processing device of (((13))), it is possible to suppress inclination of the recording medium with respect to the transport direction, compared to a configuration in which the pressing of the rotating member by the opposing member of the second second transport means is suppressed before the recording medium comes into contact with the second transport means. According to the recording medium processing device of (((14))), even if the force that the recording medium receives in the direction opposite to the transport direction is greater than in a configuration in which the recording medium processing device is not provided with a pressing member, it is possible to suppress displacement of the recording medium in the left-right direction compared to a configuration in which the recording medium being transported by the first transport means is not suppressed from being pulled by the second transport means. According to the image forming system relating to (((15))), it is possible to suppress displacement of the recording medium in the width direction, compared to a configuration in which the recording medium being transported by the first transport means is not suppressed from being pulled by the second transport means. According to the program relating to (((16))), it is possible to suppress displacement of the recording medium in the width direction compared to a configuration in which the recording medium being transported by the first transport function is not suppressed from being pulled by transport by the second transport function. [Explanation of symbols]

[0175] Reference Signs List 1: image forming system, 2: image forming device, 4: second post-processing device, 50: cutting device, 51: transport roll, 52: registration roll, 58: cutter unit, 59: crease forming device, 60: storage section, 100: information processing section, 211: CPU, P: paper

Claims

1. A first conveying means for conveying a recording medium; a cutting member arranged next to the first conveying means in a width direction of the recording medium being conveyed, the cutting member cutting the recording medium along a conveying direction of the recording medium; a second conveying means provided upstream of the first conveying means in the conveying direction and configured to convey the recording medium that has reached a predetermined conveying path; a means for suppressing or preventing a portion of the recording medium, which is conveyed by the first conveying means and whose leading edge on the upstream side in the conveying direction has not passed through the predetermined conveying path, overlapping with the cutting member in the conveying direction from being pulled by the second conveying means; A recording medium processing device comprising:

2. 2. The recording medium processing device according to claim 1, wherein the suppressing or preventing means is a forming means for forming slack in a portion of the recording medium that is transported by the first transport means and whose upstream leading edge in the transport direction has not passed the predetermined transport path, the portion being located between the first transport means and the second transport means in the transport direction.

3. the forming unit is a processor that controls a conveying speed of the recording medium by the first conveying unit and / or a conveying speed of the recording medium by the second conveying unit; The recording medium processing apparatus according to claim 2 , wherein the processor controls the conveying speed of the second conveying means to be faster than the conveying speed of the first conveying means.

4. a third conveying means provided downstream of the first conveying means in the conveying direction; a forming member provided between the first conveying means and the third conveying means in the conveying direction, the forming member forming a conveying path curved to one side in a thickness direction of the recording medium being conveyed; Further equipped with 4. The recording medium processing apparatus according to claim 3, wherein the processor controls the conveying speed of the third conveying means to be faster than the conveying speed of the first conveying means.

5. a guide member for guiding the recording medium conveyed by the first conveying means to the conveying path, the conveying path includes an overlapping conveying path that overlaps with the curved conveying path in the conveying direction and is less curved in the thickness direction than the curved conveying path or is not curved in the thickness direction; The recording medium processing device according to claim 4 , wherein the guide member guides the recording medium of a predetermined type to the curved transport path, and guides the recording medium of a different type to the overlapping transport path.

6. the forming means is a processor that controls the conveyance of the recording medium by the first conveying means and the conveyance of the recording medium by the second conveying means; 3. The recording medium processing device according to claim 2, wherein, when the recording medium being transported by the second transport means reaches the first transport means, the processor sets a period during which the first transport means does not transport the recording medium and the second transport means transports the recording medium.

7. 3. The recording medium processing device according to claim 2, wherein the forming means is provided between the second transport means and the first transport means in the transport direction, and has a forming member that forms a transport path curved on one side in the thickness direction of the recording medium being transported.

8. the forming means further includes a guide member that guides the recording medium conveyed by the second conveying means to the conveying path, the conveying path includes an overlapping conveying path that overlaps with the curved conveying path in the conveying direction and is less curved in the thickness direction than the curved conveying path or is not curved in the thickness direction; The recording medium processing device according to claim 7 , wherein the guide member guides the recording medium of a predetermined type to the curved transport path, and guides the recording medium of a different type to the overlapping transport path.

9. 3. The recording medium processing apparatus according to claim 2, wherein said forming means forms the slack in said recording medium to a degree that satisfies a predetermined condition.

10. the second conveying means includes a rotating member and an opposing member that faces the rotating member via a conveying path of the recording medium and presses the rotating member; 2. The recording medium processing device according to claim 1, wherein the suppressing or preventing means is a processor that suppresses or cancels the pressing of the opposing member against the rotating member.

11. The recording medium processing device according to claim 10 , wherein the processor suppresses or releases the pressing of the opposing member against the rotating member at least from the start of the conveying of the recording medium by the first conveying means until a predetermined condition for the conveying of the recording medium is satisfied.

12. The second conveying means includes at least a first second conveying means and a second second conveying means provided on the outer side of the first second conveying means in the width direction, the cutting member is provided on the outer side of the first conveying means in the width direction, The recording medium processing device according to claim 10 , wherein the processor suppresses the pressing of the rotating member by the opposing member of the second second transport means when the recording medium is being transported by the first second transport means.

13. The recording medium processing device according to claim 12 , wherein the processor does not suppress the pressing of the rotating member by the opposing member in the second second conveying means until the recording medium comes into contact with the second conveying means, but suppresses the pressing when the second conveying means begins to convey the recording medium.

14. 2. The recording medium processing device according to claim 1, further comprising a pressing member provided outside the cutting member in the width direction, pressing the recording medium cut by the cutting member to form a crease in the recording medium along the transport direction.

15. 15. An image forming system comprising an image forming device that forms an image on a recording medium, and a recording medium processing device that processes the recording medium on which the image has been formed by the image forming device, the recording medium processing device being configured to include the recording medium processing device according to any one of claims 1 to 14.

16. On the computer, A first conveying function for conveying the recording medium; a cutting function that cuts the recording medium being conveyed by the first conveying function along a conveying direction of the recording medium; a second conveying function for conveying the recording medium that has reached a predetermined conveying path upstream in a conveying direction of the recording medium from the conveying direction of the recording medium by the first conveying function; a function of suppressing or preventing a portion of the recording medium, which is conveyed by the first conveying function and whose leading end on the upstream side in the conveying direction has not passed through the predetermined conveying path, overlapping with a portion to be cut by the cutting function in the conveying direction from being pulled by the conveying by the second conveying function; A program to achieve this.

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