Image forming device

Abstract

To suppress an image disturbance.SOLUTION: An image formation apparatus comprises: a rotor which has a recess on an outer peripheral surface; a sprocket which integrally rotates with the rotor; a chain which has a plurality of links, is wound over the sprocket and goes around in a peripheral direction so as to shift to the linear motion from the rotational motion rotating together with the sprocket circularly along the outer periphery of the sprocket; a holding part which is fixed to the links of the chain, holds the tip of a recording medium, and conveys the recording medium by performing the rotational motion together with the rotor and the chain in a state of entering the recess and then shifting to the linear motion together with the chain; and an image formation unit which forms an image on the recording medium arranged on the outer peripheral surface of the rotor. The holding position of the recording medium of the holding part is arranged on the downstream side from an upstream side roller arranged on the upstream side in the link on the lowermost stream side in the peripheral direction among the links that are fixed with the holding part.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus. [Background technology]

[0002] Patent Document 1 discloses a printing device having at least one image carrier, an intermediate transfer body disposed opposite the image carrier and onto which an image formed on the image carrier is transferred, and a paper transport device which transports printing paper for transferring the image held on the intermediate transfer body, characterized in that the paper transport device has a chain stretched between toothed pulleys and driven to rotate so as to run from upstream to downstream in a transfer area directly below the intermediate transfer body, and a claw member fixed to the chain which clamps the printing paper fed at a paper feed position upstream of the transfer area. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2001-310444 A Summary of the Invention [Problem to be solved by the invention]

[0004] One possible image forming device is one that includes a rotating body having a recess on its outer peripheral surface, a sprocket that is arranged coaxially with the rotating body and rotates integrally with the rotating body, a chain that has multiple links and is wound around the sprocket, a holding section that is fixed to the links of the chain and holds the tip of a recording medium, and an image forming section.

[0005] In this image forming device, for example, the chain rotates in a circular arc along the outer periphery of the sprocket in the orbital direction to transition from rotational motion, in which it rotates together with the sprocket, to linear motion, and the holding part enters the recess while holding the tip of the recording medium placed on the outer periphery of the rotor, rotates together with the rotor and chain, and then transitions to linear motion together with the chain to transport the recording medium. Then, the image forming part forms an image on the recording medium placed on the outer periphery of the rotor.

[0006] Here, the image forming device may be configured such that the holding position of the recording medium in the holding unit is located upstream of the upstream roller located upstream of the downstream-most link in the rotation direction among the links to which the holding unit is fixed. In this configuration, when the holding unit transitions from rotational motion to linear motion, it may pull the recording medium, the tip of which is being held, and move the recording medium relative to the outer circumferential surface of the rotating body, causing image distortion.

[0007] The present invention aims to suppress image distortion compared to a configuration in which the holding position of the recording medium in the holding section is located upstream of the upstream roller located upstream of the downstream-most link in the rotation direction. [Means for solving the problem]

[0008] The first aspect comprises a rotating body having a recess on its outer peripheral surface, a sprocket arranged coaxially with the rotating body and rotating integrally with the rotating body, a chain having a plurality of links, wound around the sprocket and rotating in a circumferential direction so as to transition from rotational motion rotating with the sprocket in an arc along the outer periphery of the sprocket to linear motion, a holding part fixed to a link of the chain and holding a tip of a recording medium, the holding part holding the tip of a recording medium arranged on the outer peripheral surface of the rotating body and entering the recess, performing the rotational motion together with the rotating body and the chain, and then transitioning to the linear motion together with the chain, thereby transporting the recording medium, and an image forming part forming an image on the recording medium arranged on the outer peripheral surface of the rotating body, wherein the holding position of the holding part for the recording medium is arranged downstream from an upstream roller arranged upstream of the downstream-most link in the circumferential direction among the links to which the holding part is fixed.

[0009] In a second aspect, the holding position is disposed from the upstream roller in the link to a downstream roller disposed downstream in the rotation direction.

[0010] In a third aspect, the holding position is disposed inside an outer edge of the downstream roller as viewed in the axial direction.

[0011] In a fourth aspect, the holding portion is fixed to a single link, and the holding position is disposed on the link downstream from the upstream roller.

[0012] A fifth aspect includes a guide portion that guides the holding portion along a linear path along a linear path on which the chain makes a linear motion, and along an arcuate path along a circular path on which the chain makes a rotational motion.

[0013] In a sixth aspect, the guide portion guides the holding portion so that the holding portion moves in a curved manner at an inflection point between the straight path and the arc path.

[0014] In a seventh aspect, the curved path along which the holding unit moves in the curved manner is positioned other than the position where the recording medium is handed over or received from the holding unit, and the position where processing is performed on the recording medium on the rotating body.

[0015] In an eighth aspect, the curved path along which the holding portion moves in the curved manner has a curvature such that a pressure angle with respect to a guided roll guided along the curved path is 45° or less.

[0016] In a ninth aspect, the straight path is positioned downstream in the circumferential direction relative to the straight path along which the chain moves in a straight line, and the arcuate path is positioned downstream in the circumferential direction relative to the arcuate path along which the chain moves in a rotational direction.

[0017] A tenth aspect comprises a rotating body having a recess on its outer peripheral surface, a sprocket arranged coaxially with the rotating body and rotating integrally with the rotating body, a chain having a plurality of links, wound around the sprocket and orbiting in a circular direction so as to transition from rotational motion rotating with the sprocket in an arc along the outer circumference of the sprocket to linear motion, and a holding part fixed to a link of the chain and holding a tip of a recording medium, the holding part holding the tip of a recording medium arranged on the outer peripheral surface of the rotating body and entering the recess, performing the rotational motion together with the rotating body and the chain, and then transitioning to the linear motion together with the chain, thereby transporting the recording medium, and a guide part for guiding the holding part along a linear path along the linear path along which the chain moves linearly and along an arc path along which the chain moves rotationally.

[0018] In an eleventh aspect, the guide portion guides the holding portion so that the holding portion moves in a curved manner at an inflection point between the straight path and the arc path.

[0019] In a twelfth aspect, the curved path that moves the holding unit in the curved manner is positioned other than the position where the recording medium is handed over or received from the holding unit, and the position where processing is performed on the recording medium on the rotating body.

[0020] In a thirteenth aspect, the curved path along which the holding portion moves in the curved manner has a curvature such that a pressure angle with respect to a guided roll guided along the curved path is 45° or less.

[0021] In a fourteenth aspect, the straight path is positioned downstream in the circumferential direction relative to the straight path along which the chain moves in a straight line, and the arcuate path is positioned downstream in the circumferential direction relative to the arcuate path along which the chain moves in a rotational direction. Effect of the Invention

[0022] According to the first aspect of the configuration, image distortion can be suppressed compared to a configuration in which the holding position of the recording medium in the holding section is located upstream of the upstream roller located upstream of the downstream-most link in the rotation direction.

[0023] According to the second aspect of the configuration, compared to a configuration in which the holding position is located downstream of the downstream roller, it is possible to suppress the occurrence of sagging in the recording medium when the holding portion transitions from rotational motion to linear motion.

[0024] According to the configuration of the third aspect, image disturbance can be suppressed more effectively than in a configuration in which the holding position is disposed outside the outer periphery of the downstream roller.

[0025] According to the configuration of the fourth aspect, the posture of the holding portion is less likely to fluctuate compared to a configuration in which the holding portion is fixed to a plurality of links.

[0026] According to the configuration of the fifth aspect, the posture of the holding portion is less likely to fluctuate, compared to a configuration in which the holding portion moves according to the circumstances.

[0027] According to the configuration of the sixth aspect, the impact acting on the holding portion can be suppressed, compared to a configuration in which the holding portion moves by bending at an inflection point.

[0028] According to the configuration of the seventh aspect, compared to a configuration in which the curved path is positioned either at the position where the recording medium is handed over or received from the holding section, or at the position where processing is performed on the recording medium, it is possible to suppress the impact acting on the holding section without affecting the handing over and receiving of the recording medium and the processing of the recording medium.

[0029] According to the configuration of the eighth aspect, the impact acting on the retaining portion can be suppressed more effectively than in a configuration having a curvature with a pressure angle exceeding 45°.

[0030] According to the configuration of the ninth aspect, the posture of the holding portion is less likely to fluctuate compared to a configuration in which the straight path is arranged in the same position as the straight path and the arcuate path is arranged in the same position as the arcuate path in the circumferential direction of the chain.

[0031] According to the configuration of the tenth aspect, the posture of the holding portion is less likely to fluctuate, compared to a configuration in which the holding portion moves according to the circumstances.

[0032] According to the configuration of the eleventh aspect, the impact acting on the holding portion can be suppressed, compared to a configuration in which the holding portion moves by bending at an inflection point.

[0033] According to the configuration of the 12th aspect, compared to a configuration in which the curved path is positioned either at the position where the recording medium is handed over or received from the holding section, or at the position where processing is performed on the recording medium, it is possible to suppress the impact acting on the holding section without affecting the handing over and receiving of the recording medium and the processing of the recording medium.

[0034] According to the configuration of the thirteenth aspect, the impact acting on the retaining portion can be suppressed, compared to a configuration having a curvature with a pressure angle exceeding 45°.

[0035] According to the configuration of the 14th aspect, the posture of the holding portion is less likely to fluctuate compared to a configuration in which a straight path is arranged in the same position as a straight path and an arcuate path is arranged in the same position as a arcuate path in the circumferential direction of the chain. [Brief description of the drawings]

[0036] [Figure 1] 1 is a schematic diagram illustrating a configuration of an image forming apparatus according to a first embodiment. [Diagram 2] FIG. 2 is a perspective view showing the configuration of a rotating body and its surroundings according to the first embodiment. [Diagram 3] FIG. 1 is a perspective view showing a chain according to a first embodiment. [Figure 4] FIG. 2 is a side cross-sectional view showing the gripper according to the first embodiment. [Diagram 5] FIG. 2 is a perspective view showing a fixing member and a chain of the gripper according to the first embodiment. [Figure 6] FIG. 2 is a side view showing a guide portion according to the first embodiment. [Figure 7] 13 is a schematic diagram showing a movement path of the holding position in a configuration in which the holding position is disposed upstream of an upstream roller of the fixed link. FIG. [Figure 8] FIG. 8 is an operational diagram of the configuration shown in FIG. [Figure 9] FIG. 4 is a schematic diagram showing a movement path of a holding position according to the first embodiment. [Figure 10] 13 is a schematic diagram showing a movement path of the holding position in a configuration in which the holding position is disposed downstream of the downstream roller. FIG. [Figure 11] FIG. 11 is an operational diagram of the configuration shown in FIG. [Figure 12] FIG. 11 is a side view showing a guide portion according to a modified example. [Figure 13] FIG. 11 is a side view showing a guide portion according to a modified example. [Figure 14] FIG. 11 is a schematic diagram showing a configuration of an image forming apparatus according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0037] Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings. First Embodiment (Image forming apparatus 10) First, the configuration of an image forming apparatus 10 according to the first embodiment will be described. Fig. 1 is a schematic diagram showing the configuration of an image forming apparatus 10 according to this embodiment. Note that the arrow H shown in each figure indicates the vertical direction, which is the up-down direction of the apparatus, the arrow W indicates the horizontal direction, which is the width direction of the apparatus, and the arrow D indicates the horizontal direction, which is the depth direction of the apparatus (the front-rear direction of the apparatus). The dimensional ratios of the parts shown in each figure in the H direction, W direction, and D direction may differ from the actual dimensional ratios.

[0038] 1 is an inkjet type image forming apparatus that forms an ink image (one example of an image) on a recording medium P. Specifically, the image forming apparatus 10 includes an image forming section 14 and a conveying mechanism 12. Each section of the image forming apparatus 10 (the image forming section 14 and the conveying mechanism 12) will be described below.

[0039] (Image forming unit 14) The image forming unit 14 has a function of forming an ink image on the conveyed recording medium P. Specifically, as shown in Fig. 1, the image forming unit 14 has ejection units 14Y, 14M, 14C, and 14K (hereinafter, referred to as 14Y to 14K) that eject ink to predetermined ejection positions.

[0040] The discharge sections 14Y to 14K are arranged in this order toward the downstream side in the transport direction of the recording medium P. Furthermore, the discharge sections 14Y to 14K have a length along the width direction of the recording medium P. Note that the width direction of the recording medium P is a direction that intersects with the transport direction (specifically, a direction perpendicular to the transport direction) and is a direction along the front-rear direction of the apparatus.

[0041] In the image forming unit 14, the ejection units 14Y to 14K eject ink droplets onto the recording medium P transported by the transport mechanism 12 using a known method such as a thermal method or a piezoelectric method, thereby forming an ink image on the recording medium P.

[0042] (Transport mechanism 12) The transport mechanism 12 shown in Fig. 1 is a mechanism for transporting a recording medium P. As shown in Fig. 1 and Fig. 2, the transport mechanism 12 has a rotating body 50, a pair of chains 22, and a gripper 24. Note that Fig. 1 shows one of the pair of chains 22, and the chain 22 and the gripper 24 are shown in a simplified form. Also, Fig. 2 shows the gripper 24 in a simplified form.

[0043] 1, the rotor 50 is disposed opposite the discharge portions 14Y to 14K. The rotor 50 is formed in a circular shape in a side view, and has a recess 54 on its outer circumferential surface. The recess 54 is provided at a portion of the outer circumferential surface of the rotor 50 in the circumferential direction. Furthermore, the recess 54 is elongated along the axial direction of the rotor 50, and has a depth along the radial direction of the rotor 50.

[0044] As shown in Fig. 2, a pair of sprockets 25 are provided on both axial ends of the rotating body 50. The pair of sprockets 25 are arranged coaxially with the rotating body 50 and are configured to rotate integrally with the rotating body 50. The rotating body 50 and the pair of sprockets 25 are rotationally driven by a drive unit (not shown). Note that hereinafter, the axial direction of the rotating body 50 may be simply referred to as the "axial direction".

[0045] As shown in Fig. 1, a pair of sprockets 45 are disposed on one side in the device width direction (the left side in Fig. 1, downstream in the conveying direction) of the pair of sprockets 25. The pair of sprockets 45 are disposed at an interval in the device depth direction.

[0046] Further, a pair of sprockets 37 are disposed below the pair of sprockets 25 and the pair of sprockets 45, on the side of the pair of sprockets 45 relative to the pair of sprockets 25 in the width direction of the device (on the left side in FIG. 1). The pair of sprockets 37 are disposed with a gap between them in the depth direction of the device. Note that FIG. 1 shows one of the pair of sprockets 25, one of the pair of sprockets 37, and one of the pair of sprockets 45.

[0047] The pair of chains 22 are formed in a ring shape as shown in FIG. 1. The pair of chains 22 are arranged at an interval in the device depth direction (direction D in the figure) as shown in FIG. 2. Each of the pair of chains 22 is wound around each of the pair of sprockets 25, each of the pair of sprockets 37 (see FIG. 1), and each of the pair of sprockets 45 (see FIG. 1). The rotating body 50 and the pair of sprockets 25 are rotated integrally in the rotation direction B (arrow B direction), so that the chain 22 revolves in the circumferential direction C (arrow C direction). Specifically, the chain 22 revolves in the circumferential direction C in an arc shape along the outer periphery of each of the sprockets 25, 45, 37, so as to transition from a rotational motion in which the chain 22 rotates together with each of the sprockets 25, 45, 37 to a linear motion. In the following description, the upstream side of the circulating direction C of the chain 22 may simply be referred to as the "upstream" side, and the downstream side of the circulating direction C of the chain 22 may simply be referred to as the "downstream" side.

[0048] As shown in FIG. 3, the chain 22 is configured by alternately connecting a plurality of inner links 71 and a plurality of outer links 72. The inner link 71 has two inner plates 73, two bushes 75, and two rollers 77. The two bushes 75 are press-fitted into two holes 79 formed in the two inner plates 73. The two rollers 77 are rotatably supported by the two bushes 75 at their outer peripheries. The outer link 72 has two outer plates 74 and two pins 76. The two pins 76 are press-fitted into two holes 78 formed in the two outer plates 74. In the chain 22, the bushes 75 are disposed on the outer periphery of the pins 76, and the rollers 77 are disposed on the outer periphery of the bushes 75. The inner link 71 and the outer link 72 are examples of links.

[0049] 4, the gripper 24 functions as a holding portion that holds the leading end of the recording medium P. The gripper 24 has a fixed member 23, a claw 24A, a claw base 24B, and a shaft 29.

[0050] The fixed member 23 is disposed from one side of the pair of chains 22 to the other side, and has a length along the device depth direction (i.e., the axial direction of the rotating body 50) (see FIG. 5). As shown in FIGS. 4 and 5, the fixed member 23 has fixed parts 23A fixed to the chains 22 at both ends in the longitudinal direction. Specifically, the upper part of the fixed part 23A is fixed to a single outer link 72 of the chain 22. That is, the gripper 24 is fixed to the single outer link 72 by the fixed member 23.

[0051] In addition, in Figure 5, the fixed portion 23A is illustrated as being arranged at one end of the fixed member 23 in the longitudinal direction, but the fixed portion 23A is also arranged symmetrically at the other end of the fixed member 23 in the longitudinal direction, and the fixed portion 23A is fixed to the other chain 22 in a similar manner.

[0052] In this embodiment, the fixing members 23 are arranged at intervals along the circulating direction C of the chains 22, and each of the fixing members 23 is fixed to the pair of chains 22 by a fixing portion 23A.

[0053] Furthermore, each of the fixed parts 23A is provided with a bearing 21 (see FIG. 5) that rotatably supports a shaft 29 (see FIG. 4). The shaft 29 is disposed from one of the two fixed parts 23A to the other, and has a length along the device depth direction (i.e., the axial direction of the rotor 50). One end and the other end of the shaft 29 in the longitudinal direction are each rotatably supported by the bearing 21.

[0054] A plurality of claws 24A are fixed to the shaft 29 along its axial direction, and the claws 24A rotate integrally with the shaft 29. As shown in Fig. 4, the gripper 24 holds the recording medium P by pinching the tip of the recording medium P between the claws 24A and the claw base 24B. For example, the gripper 24 has the claws 24A pressed against the claw base 24B by a spring or the like, and the claws 24A are opened and closed relative to the claw base 24B by the action of a cam or the like.

[0055] In the transport mechanism 12, the leading end of the recording medium P sent from a storage unit (not shown) in which the recording medium P is stored is held by a gripper 24 on the upstream side of the discharge positions of the discharge units 14Y to 14K, as shown in Fig. 4. Furthermore, as the chain 22 rotates, the gripper 24 holding the leading end of the recording medium P moves in an arc along the outer periphery of the sprocket 25 and the rotating body 50 (see Fig. 1). As a result, the recording medium P is placed on the outer periphery of the rotating body 50.

[0056] Then, while holding the leading end of the recording medium P arranged on the outer circumferential surface of the rotating body 50 and entering the recessed portion 54, the gripper 24 rotates together with the sprocket 25, the rotating body 50, and the chain 22, and then transitions to linear motion together with the chain 22 to transport the recording medium P. As a result, the recording medium P passes the discharge positions of the discharge units 14Y to 14K, and ink droplets are discharged from the discharge units 14Y to 14K onto the recording medium P arranged on the outer circumferential surface of the rotating body 50 to form an image.

[0057] Here, in this embodiment, the holding position 24K of the gripper 24 for the recording medium P (hereinafter, sometimes simply referred to as "holding position 24K") is located downstream of the roller 77 (hereinafter, referred to as the "upstream roller 77X") located upstream of the outer link 72 (hereinafter, referred to as the "fixed link 72X") to which the gripper 24 is fixed, as shown in Figure 4.

[0058] The holding position 24K is a position where the gripper 24 holds the recording medium P, and specifically, is a position where the recording medium P is sandwiched between the claw 24A and the claw base 24B of the gripper 24. In other words, the holding position 24K can be said to be a position where the sandwiching surfaces 24C of the claw 24A and the claw base 24B that sandwich the recording medium P are disposed in a state where the recording medium P is sandwiched. Note that it is sufficient that at least a portion of the holding position 24K is disposed downstream of the upstream roller 77X of the fixed link 72X.

[0059] Moreover, the fixed link 72X is an example of "among the links to which the gripper 24 is fixed, the link on the most downstream side in the rotation direction C." In this embodiment, since the link to which the gripper 24 is fixed is a single link, the link is the most downstream link in the rotation direction C.

[0060] The upstream roller 77X in the fixed link 72X refers to the roller 77 arranged on the outer circumferential side of the pin 76 arranged on the upstream side, of the two pins 76 provided in the fixed link 72X.

[0061] The phrase "located downstream from the upstream roller 77X" includes the concept of being located at the position where the upstream roller 77X is located. Therefore, it is sufficient that the holding position 24K is located downstream from the upstream end of the upstream roller 77X in the circumferential direction C. In other words, it is sufficient that the holding position 24K is located downstream from the two-dot chain line M in FIG. 4 (a perpendicular line to the circumferential direction C that passes through the upstream end of the upstream roller 77X).

[0062] Furthermore, when viewed in the axial direction of the upstream roller 77X, the holding position 24K may be shifted relative to the chain 22 in a direction perpendicular to the circumferential direction C. In other words, when viewed in the axial direction of the upstream roller 77X, the holding position 24K does not need to overlap with the chain 22.

[0063] In this embodiment, specifically, the holding position 24K is located from the upstream roller 77X of the fixed link 72X to a roller 77 located downstream in the rotation direction C (hereinafter referred to as the "downstream roller 77Y").

[0064] The phrase "disposed between the upstream roller 77X and the downstream roller 77Y" includes the concept of being disposed at the position where the upstream roller 77X is disposed and being disposed at the position where the downstream roller 77Y is disposed. Therefore, it is sufficient that the holding position 24K is disposed between the upstream end of the upstream roller 77X in the circumferential direction C and the downstream end of the downstream roller 77Y. In other words, it is sufficient that the holding position 24K is disposed between the two-dot chain line M and the two-dot chain line N in FIG. 4 (a perpendicular line to the circumferential direction C that passes through the downstream end of the downstream roller 77Y).

[0065] More specifically, in this embodiment, the holding position 24K is disposed inside the outer edge of the downstream roller 77Y as viewed in the axial direction. That is, the holding position 24K overlaps at least one of the downstream roller 77Y, the bushing 75 disposed inside the downstream roller 77Y, and the pin 76 disposed inside the bushing 75 as viewed in the axial direction (see FIG. 4).

[0066] (Information Department 60) As shown in FIG. 6, the conveying mechanism 12 further includes a guide section 60 for guiding the gripper 24. The guide section 60 is configured with a guide groove 67 formed in a side wall 66 disposed on the axial outer side of each of the fixed sections 23A disposed at one end and the other end in the longitudinal direction of the fixed member 23 (see FIG. 5). The guide groove 67 guides a guided roll 27 as a guided section provided coaxially at one end and the other end of the axial direction of the shaft 29. Specifically, the guided roll 27 is inserted into the guide groove 67, and the guided roll 27 is guided by a guide surface 67A formed on the edge of the guide groove 67, so that the guide groove 67 guides the gripper 24 along a predetermined guide path.

[0067] In this embodiment, the guide portion 60 guides the gripper 24 along linear paths 61, 63 along linear paths 91, 93 along which the chain 22 moves linearly, and along an arcuate path 62 along an arcuate path 92 along which the chain 22 moves rotationally.

[0068] The path 92 is a path that follows part of the outer periphery of the sprockets 37, 25 at the portion where the chain 22 is wound around the sprockets 37, 25. Specifically, the path 92 is a path that follows part of the circumferential direction of the pitch circles 37P, 25P of the sprockets 37, 25.

[0069] Path 91 is connected to path 92 upstream in the orbital direction C with respect to path 92, and is a straight path that progresses toward sprockets 37, 25. Path 93 is connected to path 92 downstream in the orbital direction C with respect to path 92, and is a straight path that moves away from sprockets 37, 25 and progresses toward sprockets 25, 45. Paths 91, 93 can also be said to be paths along tangents that are tangent to pitch circles 37P, 25P of sprockets 37, 25.

[0070] The paths 91, 92, and 93 are shown as paths along which the center of the roller 77 (pin 76) of the outer link 72 of the chain 22 moves. The straight path 61, 63 and the arc path 62 are shown as paths along which the center of the guided roll 27 moves.

[0071] In this embodiment, the straight path 61 is disposed so as to be shifted downstream in the orbital direction C with respect to the path 91. The arc path 62 is disposed so as to be shifted downstream in the orbital direction C with respect to the path 92. The straight path 63 is disposed so as to be shifted downstream in the orbital direction C with respect to the path 93.

[0072] Therefore, an inflection point 6A between the straight path 61 and the arc path 62 is disposed downstream in the rotation direction C with respect to an inflection point 9A between the paths 91 and 92. Also, an inflection point 6B between the arc path 62 and the straight path 63 is disposed downstream in the rotation direction C with respect to an inflection point 9B between the paths 92 and 93.

[0073] The inflection point 6A is a position where the guided roll 27 is located when the fixed link 72X (specifically, the downstream roller 77Y) is located at the inflection point 9A. At the inflection point 6A, the straight path 61 is not tangent to the arc path 62. Similarly, the inflection point 6B is a position where the guided roll 27 is located when the fixed link 72X (specifically, the downstream roller 77Y) is located at the inflection point 9B. At the inflection point 6B, the straight path 63 is not tangent to the arc path 62.

[0074] (Action according to this embodiment) In the image forming apparatus 10 according to this embodiment, the leading end of the recording medium P sent from a storage unit (not shown) in which the recording medium P is stored is held by the gripper 24 upstream of the discharge positions of the discharge units 14Y to 14K, as shown in Fig. 4. Furthermore, as the chain 22 rotates, the gripper 24 holding the leading end of the recording medium P moves in an arc along the outer periphery of the sprocket 25 and the rotating body 50. As a result, the recording medium P is placed on the outer periphery of the rotating body 50.

[0075] Then, while holding the leading end of the recording medium P arranged on the outer circumferential surface of the rotating body 50 and entering the recessed portion 54, the gripper 24 rotates together with the sprocket 25, the rotating body 50, and the chain 22, and then transitions to linear motion together with the chain 22 to transport the recording medium P. As a result, the recording medium P passes the discharge positions of the discharge units 14Y to 14K, and ink droplets are discharged from the discharge units 14Y to 14K onto the recording medium P arranged on the outer circumferential surface of the rotating body 50 to form an image.

[0076] Here, in a configuration (hereinafter referred to as configuration A) in which the holding position 24K of the gripper 24 for the recording medium P is disposed upstream of the upstream roller 77X of the fixed link 72X, the holding position 24K and the fixed link 72X move along the path shown in Fig. 7. In Fig. 7, the path of the holding position 24K is indicated by a two-dot chain line 24T, and the path of the fixed link 72X is indicated by a dashed line 72T (similar to Figs. 9 and 10). Note that Fig. 7 is a conceptual diagram showing the path of the holding position 24K and the fixed link 72X, and each part of the fixed link 72X and the gripper 24 is shown in a simplified manner (similar to Figs. 8 to 11).

[0077] In configuration A, as indicated by dashed line 72T in Fig. 7, fixed link 72X rotates in an arc along the outer periphery of sprocket 25, and then transitions to linear motion from position PA shown in Fig. 7. Position PA is the position where chain 22 starts to separate from sprocket 25. Note that discharge position 14T of discharge portions 14Y-14K is located upstream of position PA.

[0078] Since the gripper 24 moves following the fixed link 72X, the holding position 24K rotates in an arc along the outer periphery of the sprocket 25, and then transitions to linear motion from position QA shown in Fig. 7. Therefore, the holding position 24K transitions to linear motion on the upstream side of position PA.

[0079] 8(A), (B), and (C), in configuration A, the outer circumferential surface of the rotating body 50 on which the recording medium P is placed passes through the discharge positions 14T of the dischargers 14Y to 14K and rotates in an arc to position PA, while the holding position 24K transitions to linear motion at position QA before reaching position PA. Therefore, the gripper 24 pulls the recording medium P, which may move the recording medium P downstream relative to the outer circumferential surface of the rotating body 50, causing image distortion.

[0080] In contrast, in the image forming apparatus 10 according to this embodiment, as described above, the holding position 24K for the recording medium P of the gripper 24 is disposed downstream of the upstream roller 77X in the fixed link 72X (see FIG. 4). Specifically, in this embodiment, the holding position 24K is disposed inside the outer edge of the downstream roller 77Y as viewed in the axial direction.

[0081] Therefore, the holding position 24K and the fixed link 72X move along the path shown in Fig. 9. In this embodiment, the holding position 24K, like the fixed link 72X, rotates in an arc along the outer periphery of the sprocket 25, and then transitions to linear motion from position PA.

[0082] As a result, in this embodiment, the outer circumferential surface of the rotating body 50 on which the recording medium P is placed passes through the discharge positions 14T of the discharge units 14Y to 14K and rotates in an arc to the position PA, and in synchronization with this, the holding position 24K rotates in an arc to the position PA and then transitions to a linear motion. Therefore, compared to the configuration A, the gripper 24 is prevented from pulling the recording medium P, and the occurrence of image distortion is suppressed.

[0083] In this embodiment, the gripper 24 is fixed to a single outer link 72 via the fixing member 23. Here, in a configuration in which the gripper 24 is fixed to a plurality of outer links 72 via the fixing member 23 (hereinafter referred to as configuration B), the posture of the gripper 24 fluctuates due to the influence of the postures of each of the plurality of outer links 72, and therefore the posture of the gripper 24 is likely to fluctuate.

[0084] In contrast, in this embodiment, the gripper 24 is fixed to the single outer link 72 via the fixing member 23, so that the posture of the gripper 24 is less likely to fluctuate compared to the configuration B.

[0085] (Modification of holding position 24K) In this embodiment, the holding position 24K is disposed inside the outer edge of the downstream roller 77Y as viewed in the axial direction, but is not limited thereto. For example, the holding position 24K may be disposed outside the outer edge of the downstream roller 77Y, from the upstream roller 77X to the downstream roller 77Y in the fixed link 72X. Furthermore, the holding position 24K may be disposed downstream of the downstream roller 77Y as shown in Figs. 10 and 11 (hereinafter, referred to as configuration C), and may be disposed downstream of the upstream roller 77X in the fixed link 72X.

[0086] In the configuration C, in this embodiment, the holding position 24K rotates in an arc along the outer periphery of the sprocket 25, and then transitions to linear motion from the position RA shown in Fig. 10. Therefore, the holding position 24K transitions to linear motion downstream of the position PA.

[0087] 11(A), (B), and (C), in configuration C, the outer circumferential surface of the rotating body 50 on which the recording medium P is placed passes through the discharge positions 14T of the discharge units 14Y to 14K and rotates in an arc to position PA, while the holding position 24K moves in a straight line to position RA after passing position PA. Therefore, slack occurs in the recording medium P, the tip of which is held by the gripper 24, and compared to configuration A, the gripper 24 is prevented from pulling the recording medium P, and image distortion is prevented.

[0088] In the above embodiment, as described above, the outer circumferential surface of the rotating body 50 on which the recording medium P is placed passes through the discharge positions 14T of the discharge sections 14Y-14K and rotates in an arc to position PA, and in synchronization with this, the holding position 24K rotates in an arc to position PA and then transitions to linear motion (see FIG. 9). Therefore, compared to configuration C, the occurrence of sagging in the recording medium P is suppressed, and the occurrence of wrinkles, etc. in the recording medium P is suppressed. In this respect, the above embodiment is superior to configuration C.

[0089] (Action of Guide Part 60) Next, the action of the guide portion 60 will be described.

[0090] In this embodiment, the gripper 24 is supported by a single fixed link 72X, and the holding position 24K is disposed downstream of the upstream roller 77X of the fixed link 72X, so that each part of the gripper 24 is disposed biased toward the downstream side. Therefore, the center of gravity 24J of the gripper 24 is disposed at a position away from the fixed link 72X on which the gripper 24 is supported toward the downstream side (see FIG. 4).

[0091] Here, in a configuration (hereinafter referred to as configuration D) in which the guide unit 60 is not provided and the gripper 24 moves according to the natural course of events, the center of gravity 24J of the gripper 24 is located at a position away from the fixed link 72X downstream, so that a rotational moment acts in the direction of the arrow F with the fixed link 72X (specifically, the center of the downstream roller 77Y) as a fulcrum. This makes the gripper 24 prone to tilt, and the posture of the gripper 24 prone to change.

[0092] In contrast, in this embodiment, as described above, the guide portion 60 guides the gripper 24 along linear paths 61, 63 along linear paths 91, 93 along which the chain 22 moves in a linear motion, and along an arcuate path 62 along an arcuate path 92 along which the chain 22 moves in a rotational motion (see Figure 6).

[0093] For this reason, in this embodiment, even when the chain 22 to which the gripper 24 is fixed changes from a linear motion to a rotational motion, the posture of the gripper 24 is less likely to fluctuate than in the configuration C.

[0094] In this embodiment, the straight path 61 is disposed so as to be shifted downstream in the orbital direction C with respect to the path 91. The arc path 62 is disposed so as to be shifted downstream in the orbital direction C with respect to the path 92. The straight path 63 is disposed so as to be shifted downstream in the orbital direction C with respect to the path 93.

[0095] Therefore, the guide unit 60 guides the gripper 24 while supporting a portion of the fixed link 72X that is shifted toward the downstream side in the circulating direction C, i.e., a portion of the gripper 24 that is located on the side of the center of gravity 24J of the fixed link 72X (specifically, the guided roll 27). Therefore, the posture of the gripper 24 is unlikely to fluctuate.

[0096] (Modification of the guide portion 60) In the modified example, the guide section 60 guides the gripper 24 so that the gripper 24 moves in a curved manner at an inflection point 6A between a straight path 61 and a circular path 62, and at an inflection point 6B between the circular path 62 and a straight path 63, as shown in FIG. 12.

[0097] That is, in the modified example, the straight path 61 and the arc path 62 are connected by a curved path 68 that moves the gripper 24 in a curved manner, and the arc path 62 and the straight path 63 are connected by a curved path 69 that moves the gripper 24 in a curved manner.

[0098] In addition, in the modified example, the curved paths 68, 69 are arranged at a position other than the position where the recording medium P is handed over or received by the gripper 24 and the position where the processing is performed on the recording medium P on the rotating body 50.

[0099] In the modified example, the recording medium P is handed over to and from the gripper 24 along the arcuate path 62 of the sprocket 37 (i.e., the region between the curved path 68 and the curved path 69). Also, in the modified example, the recording medium P is received by the gripper 24 at a downstream portion of the straight path 63 of the sprocket 25. Furthermore, in the modified example, as the processing of the recording medium P on the rotating body 50, the ejection processing of ink onto the recording medium P by the ejectors 14Y to 14K is performed along the arcuate path 62 of the sprocket 25 (i.e., the region between the curved path 68 and the curved path 69).

[0100] Therefore, in the modified example, the transfer or reception of the recording medium P to or from the gripper 24 and the ejection of ink onto the recording medium P are not performed on the curved paths 68 and 69.

[0101] In a further modification, as shown in Fig. 13, the curved path 68 has a curvature at an inflection point 6A such that the pressure angle θA with the guided roll 27 is 45° or less. The pressure angle θA is the angle between the swing direction of the guided roll 27 (arrow 27A in Fig. 13) and a perpendicular line 27F to the guide surface 67A. The swing direction of the guided roll 27 (arrow 27A in Fig. 13) is the direction in which the guided roll 27 swings around the center of the downstream roller 77Y. The guided roll 27 swings around the center of the downstream roller 77Y.

[0102] In a typical cam, the maximum pressure angle of the swing follower at which the cam can move smoothly is 45°. Following this, in this embodiment, the pressure angle is set to 45° or less.

[0103] In this modified example, as described above, the guide section 60 guides the gripper 24 so that the gripper 24 moves in a curved manner at the inflection point 6A between the straight path 61 and the arc path 62 and at the inflection point 6B between the arc path 62 and the straight path 63.

[0104] Therefore, compared to a configuration in which the gripper 24 moves while bending at the inflection points 6A and 6B, the movement direction of the gripper 24 is less likely to change suddenly, and impacts acting on the gripper 24 are suppressed.

[0105] Furthermore, in the modified example, as described above, the curved paths 68, 69 are disposed at a position other than the position where the recording medium P is handed over to or received by the gripper 24 and the position where processing is performed on the recording medium P on the rotating body 50. Therefore, compared to a configuration in which the curved paths 68, 69 are disposed at either the position where the recording medium P is handed over to or received by the gripper 24 and the position where processing is performed on the recording medium P, the impact acting on the gripper 24 is suppressed without affecting the handover and reception of the recording medium P and the processing of the recording medium P.

[0106] Furthermore, in the modified example, as described above, the curved path 68 has a curvature at the inflection point 6A such that the pressure angle with the guided roll 27 is 45° or less.

[0107] Here, in a configuration in which the curved path 68 has a curvature with the pressure angle exceeding 45° (hereinafter referred to as configuration E), the load (surface pressure load) on the guide surface in contact with the guided roll 27 is large, and the guided roll 27 cannot move smoothly. In contrast, in the modified example, the curved path 68 has a curvature with the pressure angle being 45° or less, so the load (surface pressure load) on the guide surface in contact with the guided roll 27 is small, and the guided roll 27 can move smoothly, thereby suppressing the impact acting on the gripper 24.

[0108] Incidentally, the processes performed on the recording medium P include a transfer process, a fixing process, and the like in the electrophotographic image forming apparatus 200 described later.

[0109] (Other variations) In the present embodiment, the gripper 24 is fixed to a single outer link 72 via the fixing member 23, but this is not limiting. For example, the gripper 24 may be configured to be fixed to a plurality of outer links 72 via the fixing member 23. In the case of this configuration, the holding position 24K is disposed downstream of the upstream roller 77X in the most downstream link in the circulating direction C, among the plurality of outer links 72 to which the gripper 24 is fixed.

[0110] In the present embodiment, the guide unit 60 guides the gripper 24 along the linear paths 61, 63 along the linear paths 91, 93 along which the chain 22 moves linearly and along the arc path 62 along the arc path 92 along which the chain 22 moves rotationally, but this is not limited thereto. For example, the transport mechanism 12 may be configured not to have the guide unit 60 and to move the gripper 24 as the situation unfolds.

[0111] In addition, as described above, the guide unit 60 according to the modified example guides the gripper 24 so that the gripper 24 moves in a curved line at the inflection point 6A between the straight path 61 and the arc path 62 and the inflection point 6B between the arc path 62 and the straight path 63, but is not limited to this. For example, the gripper 24 may be configured to move while bending at the inflection points 6A and 6B.

[0112] In addition, in the guide unit 60 according to the modified example, the curved paths 68, 69 are arranged at a position other than the position where the recording medium P is handed over to or received by the gripper 24 and the position where the processing is performed on the recording medium P on the rotating body 50, but this is not limited to the above. For example, the curved paths 68, 69 may be arranged at either the position where the recording medium P is handed over to or received by the gripper 24 and the position where the processing is performed on the recording medium P.

[0113] In the guide section 60 according to the modified example, the curved path 68 has a curvature at the inflection point 6A such that the pressure angle with the guided roll 27 is 45° or less, but this is not limited thereto. For example, the curved path 68 may have a curvature such that the pressure angle exceeds 45°.

[0114] In the present embodiment, the gripper 24 holds the recording medium P by pinching the leading end of the recording medium P, but is not limited to this. As an example of the holding portion, for example, a configuration in which the leading end of the recording medium P is held by an air sucking force, an adhesive force, or the like may be used.

[0115] <Second embodiment> (Image forming apparatus 200) In the first embodiment, the image forming apparatus 10 is an inkjet type image forming apparatus that forms an image on a recording medium P using ink, but the image forming apparatus is not limited to this. An example of the image forming apparatus may be, for example, an electrophotographic image forming apparatus, and may be any apparatus that forms an image. In the second embodiment, an electrophotographic image forming apparatus 200 will be described. FIG. 14 is a schematic diagram showing the configuration of the image forming apparatus 200 according to this embodiment. Note that parts having the same functions as those in the first embodiment are given the same reference numerals, and descriptions thereof will be omitted as appropriate.

[0116] (Image forming unit 214) The image forming apparatus 200 has an image forming section 214 instead of the image forming section 14. The image forming section 214 has a function of forming a toner image (one example of an image) on the recording medium P by an electrophotographic method. More specifically, as shown in FIG. 14, the image forming section 214 has a toner image forming section 222 that forms a toner image, and a transfer device 217 that transfers the toner image formed by the toner image forming section 222 onto the recording medium P.

[0117] (Toner image forming unit 222) A plurality of toner image forming units 222 shown in Fig. 14 are provided so as to form toner images for each color. In this embodiment, toner image forming units 222 for a total of four colors, yellow (Y), magenta (M), cyan (C), and black (K), are provided. (Y), (M), (C), and (K) shown in Fig. 14 indicate components corresponding to the above-mentioned respective colors.

[0118] In addition, since the toner image forming units 222 of each color are configured in the same manner except for the toner used, in FIG. 14, the respective parts of the toner image forming unit 222(K) are denoted by reference numerals as a representative of the toner image forming units 222 of each color.

[0119] Specifically, each of the toner image forming units 222 for each color has a photoconductor 224 that rotates in one direction (for example, the counterclockwise direction in FIG. 14). Each of the toner image forming units 222 for each color also has a charger 223, an exposure device 240, and a developing device 238.

[0120] In the toner image forming section 222 for each color, the charger 223 charges the photoconductor 224. Furthermore, the exposure device 240 exposes the photoconductor 224 charged by the charger 223 to light, thereby forming an electrostatic latent image on the photoconductor 224. Furthermore, the development device 238 develops the electrostatic latent image formed on the photoconductor 224 by the exposure device 240, thereby forming a toner image.

[0121] (Transfer device 217) 14 is a device that transfers the toner image formed by the toner image forming unit 222 onto a recording medium P. Specifically, the transfer device 217 primarily transfers the toner images of the photoconductors 224 of each color onto a transfer belt 213 serving as an intermediate transfer body, and then secondarily transfers the superimposed toner images onto the recording medium P. As shown in FIG. 14, the transfer device 217 includes the transfer belt 213, a primary transfer roll 226, and a transfer body 250.

[0122] The primary transfer roll 226 is a roll that transfers the toner image of each color of the photoconductor 224 to the transfer belt 213 at a primary transfer position T1 between the photoconductor 224 and the primary transfer roll 226. In this embodiment, a primary transfer electric field is applied between the primary transfer roll 226 and the photoconductor 224, so that the toner image formed on the photoconductor 224 is transferred to the transfer belt 213 at the primary transfer position T1.

[0123] A toner image is transferred from each photoconductor 224 of each color onto the outer peripheral surface of the transfer belt 213. As shown in Fig. 14, the transfer belt 213 is endless and is wound around a plurality of rolls 232 and an opposing roll 234 so as to assume an inverted triangular shape when viewed from the front (when viewed toward the depth of the device). The transfer belt 213 rotates in the direction of arrow A when at least one of the plurality of rolls 232 is driven to rotate.

[0124] The transfer body 250 is a roll that transfers the toner image transferred to the transfer belt 213 to the recording medium P at a secondary transfer position T2 between the opposing roll 234 and the transfer body 250. In this embodiment, a secondary transfer electric field is applied between the opposing roll 234 and the transfer body 250, so that the toner image transferred to the transfer belt 213 is transferred to the recording medium P at the secondary transfer position T2. ​​The transfer body 250 is configured similarly to the rotating body 50 in the first embodiment, and is an example of a rotating body.

[0125] (Fixing device 80) In this embodiment, the fixing device 80 functions as a device that fixes the toner image transferred to the recording medium P by the transfer body 250 to the recording medium P. Specifically, the fixing device 80 has a pressure roll 81 and a heating roll 82, as shown in FIG.

[0126] The pair of sprockets 45 in the first embodiment are provided on both axial ends of the pressure roll 81. The pair of sprockets 45 are arranged coaxially with the pressure roll 81 and are configured to rotate integrally with the pressure roll 81. In addition, a recess 84 is formed on the outer periphery of the pressure roll 81 in which the gripper 24 and the fixing member 23 are housed.

[0127] In the fixing device 80, a heating roll 82 is disposed above the pressure roll 81. The heating roll 82 has a heat source 82A, such as a halogen lamp, inside the roll.

[0128] Furthermore, in the fixing device 80, for example, one of the pressure roll 81 and the heating roll 82 is rotationally driven, and the other of the pressure roll 81 and the heating roll 82 is rotated by the pressure roll 81. Note that a configuration in which both the pressure roll 81 and the heating roll 82 are rotationally driven may also be used.

[0129] In the fixing device 80, the recording medium P is sandwiched between a heating roll 82 and a pressure roll 81 and transported while being heated and pressurized, thereby fixing the toner image transferred to the recording medium P to the recording medium P.

[0130] In the image forming apparatus 200, the conveying mechanism 12 rotates the chain 22 in the circumferential direction C with the gripper 24 holding the leading end of the recording medium P, thereby passing the recording medium P through the secondary transfer position T2 and the fixing position NP between the pressure roll 81 and the heating roll 82. Then, the toner images of each color that have been primarily transferred and superimposed on the transfer belt 213 at the primary transfer position T1 are secondarily transferred onto the recording medium P at the secondary transfer position T2. ​​The toner images secondarily transferred onto the recording medium P are fixed onto the recording medium P at the fixing position NP.

[0131] The transport mechanism 12 and the guide section 60 in this embodiment are configured similarly to the transport mechanism 12 and the guide section 60 in the first embodiment, and this embodiment achieves the same functions as the first embodiment.

[0132] The present invention is not limited to the above-described embodiment, and various modifications, changes, and improvements are possible without departing from the spirit and scope of the present invention. For example, the above-described modified examples may be appropriately combined to form a configuration. [Explanation of symbols]

[0133] 6A Inflection Point 6B Inflection Point 10 Image forming device 14 Image forming section 22 Chain 24 Gripper (an example of a holding part) 24K holding position 25 sprocket 50 Rotating Body 54 Recess 60 Information Department 61 Straight Path 62 Circular Path 63 Straight Path 68 Curved Path 69 Curved Path 71 Internal links (example of links) 72 External links (example of a link) 72X Permanent link (example link) 77X Upstream roller 77Y Downstream roller 200 Image forming device 214 Image forming section P Recording medium

Claims

1. A rotor having a recess on an outer circumferential surface thereof; a sprocket provided coaxially with the rotor and rotating integrally with the rotor; a chain including a plurality of links, wound around the sprocket, and rotating in a circumferential direction so as to transition from a rotational motion that rotates together with the sprocket in an arc along the outer periphery of the sprocket to a linear motion; a holding section fixed to a link of the chain and holding a leading end of a recording medium, the holding section holding a leading end of a recording medium arranged on an outer circumferential surface of the rotating body and entering the recess, the holding section rotating together with the rotating body and the chain, and then shifting to a linear motion together with the chain to transport the recording medium; an image forming unit that forms an image on the recording medium disposed on the outer circumferential surface of the rotating body; a guide portion that guides the holding portion along a linear path along a linear path on which the chain moves linearly and along an arcuate path along which the chain moves rotationally; Equipped with The holding position of the recording medium in the holding unit is the link to which the holding portion is fixed is disposed downstream of an upstream roller disposed upstream of a downstream-most link in the circumferential direction, the guide portion guides the holding portion such that the holding portion moves in a curved manner at an inflection point between the straight line path and the arc path, The curved path along which the holding unit moves in the curved line is disposed other than a position where the recording medium is transferred to or received from the holding unit and a position where processing is performed on the recording medium on the rotating body. Image forming device.

2. A rotating body having a recess on its outer circumferential surface, a sprocket provided coaxially with the rotor and rotating integrally with the rotor; a chain including a plurality of links, wound around the sprocket, and rotating in a circumferential direction so as to transition from a rotational motion that rotates together with the sprocket in an arc along the outer periphery of the sprocket to a linear motion; a holding section fixed to a link of the chain and holding a leading end of a recording medium, the holding section holding a leading end of a recording medium arranged on an outer circumferential surface of the rotating body and entering the recess, the holding section rotating together with the rotating body and the chain, and then shifting to a linear motion together with the chain to transport the recording medium; an image forming unit that forms an image on the recording medium disposed on the outer circumferential surface of the rotating body; a guide portion that guides the holding portion along a linear path along a linear path on which the chain moves linearly and along an arcuate path along which the chain moves rotationally; Equipped with The holding position of the recording medium in the holding unit is the link to which the holding portion is fixed is disposed downstream of an upstream roller disposed upstream of a downstream-most link in the circumferential direction, The linear path is disposed downstream in the circulating direction relative to a linear path along which the chain moves linearly, The arcuate path is disposed downstream in the circulating direction with respect to the arcuate path along which the chain rotates. Image forming device.

3. The holding position is disposed from the upstream roller in the link to a downstream roller disposed downstream in the rotation direction.

3. The image forming apparatus according to claim 1 or 2.

4. The holding position is disposed inside an outer edge of the downstream roller when viewed in the axial direction. The image forming apparatus according to claim 3 .

5. The retaining portion is fixed to a single link, The holding position is disposed downstream of the upstream roller in the link. The image forming apparatus according to any one of claims 1 to 4.

6. The curved path along which the holding portion is moved in the curved manner has a curvature such that the pressure angle with the guided roll guided by the curved path is 45° or less. The image forming apparatus according to claim 1 .

7. A rotating body having a recess on an outer peripheral surface, a sprocket provided coaxially with the rotor and rotating integrally with the rotor; a chain including a plurality of links, wound around the sprocket, and rotating in a circumferential direction so as to transition from a rotational motion that rotates together with the sprocket in an arc along the outer periphery of the sprocket to a linear motion; a holding section fixed to a link of the chain and holding a leading end of a recording medium, the holding section holding a leading end of a recording medium arranged on an outer circumferential surface of the rotating body and entering the recess, the holding section rotating together with the rotating body and the chain, and then shifting to a linear motion together with the chain to transport the recording medium; a guide portion that guides the holding portion along a linear path along a linear path on which the chain moves linearly and along an arcuate path along which the chain moves rotationally; Equipped with the guide portion guides the holding portion such that the holding portion moves in a curved manner at an inflection point between the straight line path and the arc path, The curved path along which the holding unit moves in the curved line is disposed other than a position where the recording medium is transferred to or received from the holding unit and a position where processing is performed on the recording medium on the rotating body. Image forming device.

8. A rotating body having a recess on an outer circumferential surface, a sprocket provided coaxially with the rotor and rotating integrally with the rotor; a chain including a plurality of links, wound around the sprocket, and rotating in a circumferential direction so as to transition from a rotational motion that rotates together with the sprocket in an arc along the outer periphery of the sprocket to a linear motion; a holding section fixed to a link of the chain and holding a leading end of a recording medium, the holding section holding a leading end of a recording medium arranged on an outer circumferential surface of the rotating body and entering the recess, the holding section rotating together with the rotating body and the chain, and then shifting to a linear motion together with the chain to transport the recording medium; a guide portion that guides the holding portion along a linear path along a linear path on which the chain moves linearly and along an arcuate path along which the chain moves rotationally; Equipped with The linear path is disposed downstream in the circulating direction relative to a linear path along which the chain moves linearly, The arcuate path is disposed downstream in the circulating direction with respect to the arcuate path along which the chain rotates. Image forming device.

9. The curved path along which the holding portion is moved in the curved manner has a curvature such that the pressure angle with the guided roll guided along the curved path is 45° or less. The image forming apparatus according to claim 7.

Images