Body member and image forming apparatus

Abstract

To improve the adhesion of a sheet member to a cylinder body in comparison to a case where an end of a metal layer of the sheet member is freely movable in the circumferential direction of the cylinder body.SOLUTION: A transfer cylinder 50 comprises: a cylinder body 54 which has a recess 54 and is in the substantially cylindrical shape; a sheet member 100 which is wound around the cylinder body 54 and has a metal layer 150 and an outer layer 102 coming into contact with the cylinder body 54; a first attachment member 110 which is provided in the metal layer 150 of one end 100A of the sheet member 100 and is detachably attached to one side of the recess 54; a second attachment member 120 which is provided in an end 152 of the metal layer 150 of the other end 100B of the sheet member 100 and is detachably attached to the other side of the recess 54; a tension applying screw 72 which applies tension to the metal layer 150 by pulling the second attachment member 120 in the depth direction of the recess 54; a positioning pin 211 which is provided in the second attachment member 120; and a positioning hole 210B to which a positioning pin 211 formed on the end 152 of the metal layer 150 is fit.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a body member and an image forming apparatus.

Background Art

[0002] A transfer device that has a conveying means for moving a transfer material along a circulating path, and a gripper piece that is attached to the conveying means, supported by a rotating shaft, rotates with respect to a base member, and grips the leading edge side of the transfer material, is conventionally known (for example, see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to improve the adhesion of a sheet member to a body main body as compared with a case where an end portion of a metal layer of the sheet member is freely movable in the circumferential direction of the body main body.

Means for Solving the Problems

[0005] The first aspect is a sheet member having a body main body with a substantially circular cross-section having a recess along the axial direction, a metal layer wound around the body main body and in contact with the body main body, and an outer layer laminated on the metal layer, a first attachment member provided at one end of the sheet member and removably attached to one side in the circumferential direction in the recess, a second attachment member provided at an end of the metal layer protruding in the circumferential direction from the outer layer at the other end of the sheet member and removably attached to the other side in the circumferential direction in the recess, a tension applying mechanism that pulls the second attachment member in the depth direction of the recess to apply tension to the metal layer, a convex portion provided on one of the second attachment member and the end of the metal layer, and a fitting portion provided on the other of the second attachment member and the end of the metal layer, into which the convex portion fits, and is a body member.

[0006] The second aspect is the body member according to the first aspect, wherein the tension applying mechanism has a second base portion provided on the other side in the circumferential direction in the recess, a guide pin protruding in the depth direction of the recess from one of the second base portion and the second attachment member and passed through a guide hole formed in the other of the second base portion and the second attachment member, and fixing means for fixing the second attachment member to the second base portion.

[0007] The third aspect is the body member according to the second aspect, wherein the fixing means is a screw, and the screw passes through a second through hole formed in the second attachment member and smaller than the head of the screw, and the tip end is screwed into the second base portion.

[0008] The fourth aspect is the body member according to the third aspect, wherein the second attachment member has a fixed portion and a fixed-on portion in which the second through hole and the guide hole are formed and which are fastened with a screw, and the end of the metal layer is sandwiched between the fixed portion and the fixed-on portion.

[0009] In a fifth aspect, on one side in the circumferential direction in the recessed portion, there is provided a first base portion to which the first attachment member is attached by a screw passed through a first through-hole formed in the first attachment member and smaller than the head, and the first through-hole of the first attachment member has a position defined along the axial direction of the body main body with reference to the convex portion or the fitting portion provided in the second attachment member. The body member according to any one of the first to fourth aspects.

[0010] In a sixth aspect, the first attachment member has an overhanging portion having a pair of overhanging portions protruding from both sides in the axial direction of the body main body from the sheet member, and the first through-hole is formed in the overhanging portion. The body member according to the fifth aspect.

[0011] In a seventh aspect, the first attachment member has a pair of the overhanging portions and a central portion disposed between the pair of the overhanging portions, and the central portion is disposed within the range of the sheet member when viewed in the thickness direction of the sheet member. The body member according to the sixth aspect.

[0012] In an eighth aspect, the first base portion is provided with a positioning portion that abuts against and positions the first attachment member in the circumferential direction. The body member according to any one of the fifth to seventh aspects.

[0013] In a ninth aspect, the positioning portion restricts the movement of the first attachment member outward in the radial direction by hitting the first attachment member in the radial direction of the body main body in a state where the first attachment member is abutted in the circumferential direction. The body member according to the eighth aspect.

[0014] In a tenth aspect, there is provided an image forming apparatus including the body member according to any one of the first to ninth aspects that conveys a recording medium, and an image forming portion that forms an image on the recording medium conveyed by the body member.

Advantages of the Invention

[0015] According to the barrel member described in the first aspect, the adhesion of the sheet member to the barrel body is improved as compared with the case where the end of the metal layer of the sheet member is freely movable in the circumferential direction of the barrel body.

[0016] According to the barrel member described in the second aspect, the adhesion of the sheet member to the barrel body is improved as compared with the case where the second attachment member is not positioned so as to be movable in the depth direction.

[0017] According to the barrel member described in the third aspect, the tension applied to the metal layer of the sheet member can be adjusted by the screwing amount of the screw.

[0018] According to the barrel member described in the fourth aspect, a larger tension can be applied to the end of the metal layer as compared with the case where the end of the metal layer is adhered to the second attachment member.

[0019] According to the barrel member described in the fifth aspect, the mounting accuracy of the first attachment member is improved as compared with the case where the position of the first through hole of the first attachment member is defined with reference to the end of the sheet member.

[0020] According to the barrel member described in the sixth aspect, the lifting on both sides in the axial direction at one end of the sheet member is suppressed as compared with the case where only the middle layer portion in the axial direction of the first attachment member is fastened to the first pedestal portion with screws.

[0021] According to the barrel member described in the seventh aspect, the range along the circumferential direction of the sheet member disposed on the barrel body can be increased as compared with the case where the central portion of the first attachment member protrudes from one end of the sheet member.

[0022] According to the barrel member described in the eighth aspect, the inclination of the sheet member with respect to the barrel body is suppressed as compared with the case where the first attachment member is freely movable in the circumferential direction.

[0023] According to the barrel member described in the ninth aspect, the lifting of one end of the sheet member from the barrel body is suppressed as compared with the case where the first attachment member is freely movable to the outside in the radial direction of the barrel body.

[0024] According to the image forming apparatus described in the tenth aspect, the occurrence of image quality defects is suppressed as compared with the case where the end portion of the metal layer of the sheet member is movable freely in the circumferential direction of the body main body.

Brief Description of the Drawings

[0025]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Embodiments for Carrying Out the Invention

[0026] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. For the sake of convenience of explanation, the direction along the arrow H shown in FIG. 1 is defined as the vertical direction of the image forming apparatus 10, the direction along the arrow W is defined as the width direction of the image forming apparatus 10, and the direction along the arrow D is defined as the front-rear direction of the image forming apparatus 10.

[0027] As shown in FIG. 1, the image forming apparatus 10 is, as an example, an inkjet system for forming an ink image as an example of an image on a recording medium P. The image forming apparatus 10 includes an image forming unit 12, a conveyance unit 14, and a fixing device 90.

[0028] Hereinafter, the image forming unit 12, the conveyance unit 14, and the fixing device 90 of the image forming apparatus 10 will be described, and then a transfer cylinder 50 as an example of a body member will be described.

[0029] (Image Forming Unit) As shown in FIG. 1, the image forming unit 12 has a function of forming an ink image on the recording medium P. Specifically described, the image forming unit 12 includes a transfer belt 30 as an example of an intermediate transfer member, a plurality of, in this embodiment, two rolls 22, an opposing roll 24 as an example of a rotating member, an adhesive layer forming device 26, a particle supply device 18, a discharge head 20, a transfer body 40, and a cleaner 28.

[0030] The transfer belt 30 is formed in an endless shape and is wound around the two rolls 22 and the opposing roll 24 so as to have an inverted triangular posture when viewed from the front-rear direction. The transfer belt 30 is configured to circulate in the direction of arrow A by driving at least one of the two rolls 22 to rotate.

[0031] The adhesive layer forming device 26, the particle supply device 18, the discharge head 20, the transfer body 40, and the cleaner 28 are arranged on the outer peripheral surface side of the transfer belt 30 in this order from the upstream side in the circumferential direction of the transfer belt 30 (hereinafter referred to as the "belt circumferential direction").

[0032] The adhesive layer forming device 26 is disposed at one end (the left side in the figure) in the device width direction of the horizontal portion of the transfer belt 30 in an inverted triangular posture. The adhesive layer forming device 26 stores an adhesive therein, and forms an adhesive layer (not shown) by applying the adhesive to the outer peripheral surface of the transfer belt 30 that moves in a circular motion. As the adhesive, for example, glue, organic solvents, etc. are used.

[0033] The particle supply device 18 is disposed on the downstream side (the right side in the figure) in the belt circumferential direction with respect to the adhesive layer forming device 26 in the horizontal portion of the transfer belt 30. The particle supply device 18 stores ink-receptive particles 16 that can receive ink droplets therein, and supplies the ink-receptive particles 16 to the transfer belt 30 on which the adhesive layer is formed.

[0034] That is, the ink-receptive particles 16 supplied onto the transfer belt 30 by the particle supply device 18 adhere to the adhesive layer by the adhesive force of the adhesive layer, and an ink-receptive particle layer 16A is formed on the transfer belt 30.

[0035] The ejection head 20 is disposed on the downstream side (the right side in the figure) in the belt circumferential direction with respect to the particle supply device 18 in the horizontal portion of the transfer belt 30. A plurality of ejection heads 20 are provided to form ink images for each color. In the present embodiment, four-color ejection heads 20 for yellow (Y), magenta (M), cyan (C), and black (K) are provided. In FIG. 1, English letters Y, M, C, and K are attached after the reference numeral 20 corresponding to each of the above colors.

[0036] Further, each color ejection head 20 ejects ink droplets from a nozzle (not shown) to the ink-receptive particle layer 16A by a known method such as a thermal method or a piezoelectric method to form an ink image based on image data. That is, the ink droplets ejected from each color ejection head 20 are received by the ink-receptive particle layer 16A to form an ink image.

[0037] The transfer body 40 is disposed below the transfer belt 30. As shown in FIG. 2, the transfer body 40 has a transfer cylinder 50 disposed such that its axial direction is the same as that of the opposing roll 24. The transfer cylinder 50 is disposed to face the transfer belt 30 and is configured to form a sandwiching region T that sandwiches the transfer belt 30 with the opposing roll 24.

[0038] In the present embodiment, due to the circumferential movement of the transfer belt 30, the ink image formed on the ink-receptive particle layer 16A is conveyed to the sandwiching region T, and the recording medium P is conveyed to the sandwiching region T by the conveying unit 14. Then, the transfer cylinder 50 sandwiches and pressurizes the recording medium P and the ink image conveyed to the sandwiching region T with the transfer belt 30, thereby transferring the ink image to the recording medium P.

[0039] In FIG. 1, the conveying direction of the recording medium P is indicated by an arrow X. Also, when sandwiching and pressurizing the recording medium P and the ink image with the transfer belt 30 in the sandwiching region T, the transfer cylinder 50 may heat the recording medium P and the ink image. Further, a concave portion 54 for accommodating a gripper 36 and a support member 38, which will be described later, is formed in a part of the outer peripheral surface of the transfer cylinder 50.

[0040] As shown in FIG. 2, a pair of sprockets 32 are provided on both axial ends of the transfer cylinder 50. The pair of sprockets 32 are coaxially disposed with the transfer cylinder 50 and are configured to rotate integrally with the transfer cylinder 50. Then, the transfer cylinder 50 is configured to be rotationally driven by a driving unit (not shown). Also, a chain 34, which will be described later, is wound around the pair of sprockets 32.

[0041] As shown in FIG. 1, the cleaner 28 is disposed on the downstream side in the belt circumferential direction with respect to the sandwiching region T and on the upstream side in the belt circumferential direction with respect to the adhesive layer forming device 26. The cleaner 28 includes a blade 28A that contacts the outer peripheral surface of the transfer belt 30. As the transfer belt 30 moves in a circular motion, the cleaner 28 removes the adhesive layer, ink-receptive particles 16, ink, and other foreign matters (e.g., paper dust when the recording medium P is paper) remaining on the transfer belt 30 after passing through the sandwiching region T with the blade 28A.

[0042] Note that the opposing roll 24 is movable between a contact position where it contacts the transfer cylinder 50 and a separation position where it is separated from the transfer cylinder 50 by a transfer movement mechanism (not shown) using a cam or the like. Specifically, the opposing roll 24 is constantly pressed or pulled toward the contact position by the elastic force of an elastic member such as a spring, and is configured to move to the separation position against the elastic force by the transfer movement mechanism.

[0043] (Fixing device) As shown in FIG. 1, the fixing device 90 is a device that fixes the ink image transferred onto the recording medium P to the recording medium P. Specifically, the fixing device 90 includes a pressure member 42 disposed on the downstream side in the conveyance direction of the recording medium P in the conveyance unit 14, and a heating roll 92.

[0044] As shown in FIG. 3, the pressure member 42 has a pressure roll 44 disposed such that its axial direction is the same as the axial direction of the transfer cylinder 50. A pair of sprockets 48 are provided on both axial ends of the pressure roll 44. The pair of sprockets 48 are coaxially disposed with the pressure roll 44 and are configured to rotate integrally with the pressure roll 44. A chain 34 described later is wound around the pair of sprockets 48.

[0045] As shown in FIG. 1, the heating roll 92 and the pressure roll 44 are arranged vertically. That is, the heating roll 92 is arranged above the pressure roll 44. This heating roll 92 has a heating source 90A (see FIG. 1) such as a halogen lamp inside. In the following, the position where the recording medium P is sandwiched between the heating roll 92 and the pressure roll 44 is defined as the sandwiching position NP.

[0046] Further, the heating roll 92 is movable between a contact position where it contacts the pressure roll 44 and a separation position where it is separated from the pressure roll 44 by a fixing movement mechanism (not shown) using a cam or the like. Specifically, the heating roll 92 is always pressed or pulled toward the contact position by the elastic force of an elastic member such as a spring, and is configured to move to the separation position against the elastic force by the fixing movement mechanism. And the heating roll 92 is configured to sandwich the recording medium P with the pressure roll 44 at the contact position.

[0047] In this embodiment, the heating roll 92 is configured to be rotationally driven and the pressure roll 44 is configured to rotate passively, but both the heating roll 92 and the pressure roll 44 may be configured to be rotationally driven. Also, a concave portion 46 for accommodating a gripper 36 and a support member 38, which will be described later, is formed in a part of the outer peripheral surface of the pressure roll 44.

[0048] (Conveying unit) As shown in FIGS. 1 to 3, the conveying unit 14 has a function of conveying the recording medium P and passing it through the sandwiching region T and the sandwiching position NP. The conveying unit 14 has a pair of chains 34 and a gripper 36. The pair of chains 34 is an example of a driving force transmission member, and the gripper 36 is an example of a holding member that holds the leading end portion of the recording medium P. Note that in FIG. 1, the chains 34 and the gripper 36 are shown in a simplified manner.

[0049] As shown in FIG. 1, a pair of chains 34 are each formed in a ring shape. And as shown in FIGS. 2 and 3, this pair of chains 34 are arranged at intervals in the depth direction of the apparatus. That is, this pair of chains 34 are respectively wound around a pair of sprockets 32 coaxially provided on the transfer cylinder 50 and a pair of sprockets 48 coaxially provided on the pressure roll 44.

[0050] When the transfer cylinder 50 is rotationally driven by a drive unit (not shown), a pair of sprockets 25 rotate integrally in the rotational direction B (arrow B direction), so that the chain 34 circulates in the circumferential direction C (arrow C direction). Also, thereby the pressure roll 44 is driven to rotate passively. That is, the rotational driving force of the transfer cylinder 50 is transmitted to the pressure roll 44 by a pair of chains 34 that circulate in the circumferential direction C (see FIG. 1).

[0051] Also, as shown in FIGS. 2 and 3, a support member 38 to which a gripper 36 is attached is bridged along the depth direction of the apparatus on a pair of chains 34. A plurality (three in the case shown in FIG. 1) of support members 38 are provided, and each support member 38 is fixed to the pair of chains 34 at a predetermined interval along the circumferential direction (circumferential direction C) of the chain 34.

[0052] Also, a plurality of grippers 36 are arranged side by side and attached to each support member 38 at a predetermined interval along the depth direction of the apparatus. That is, each gripper 36 is attached to the chain 34 via each support member 38. And each gripper 36 has a holding function of holding the leading end portion of the recording medium P.

[0053] Specifically described, as shown in FIG. 4, the gripper 36 has a plurality of claws 36A and a plurality of claw bases 36B. The gripper 36 is configured to hold the recording medium P by sandwiching the leading end portion of the recording medium P between each claw 36A and each claw base 36B. Therefore, the gripper 36 can also be said to be an example of a sandwiching portion that sandwiches the recording medium P in the thickness direction.

[0054] Further, the gripper 36 is disposed on the downstream side in the conveyance direction with respect to the recording medium P, and is configured to hold the leading end portion of the recording medium P from the downstream side in the conveyance direction of the recording medium P. Note that the gripper 36 is configured such that, for example, the claw 36A is pressed against the claw base 36B by a spring or the like, and the claw 36A is separated from the claw base 36B by the action of a cam or the like.

[0055] In this way, in the conveyance unit 14, the leading end portion of the recording medium P sent from an accommodating unit (not shown) is held by the gripper 36. Then, in the conveyance unit 14, with the gripper 36 holding the leading end portion of the recording medium P, the chain 34 moves in the circumferential direction C, thereby moving the gripper 36 to convey the recording medium P, and passing the sandwiching region T together with the gripper 36 while the recording medium P is held by the gripper 36.

[0056] Note that in the portion where the chain 34 is wound around the sprocket 32, the gripper 36 is configured to move in the rotational direction of the transfer cylinder 50 integrally with the transfer cylinder 50 while being accommodated in the concave portion 54 of the transfer cylinder 50. Similarly, in the portion where the chain 34 is wound around the sprocket 48, the gripper 36 is configured to move in the rotational direction of the pressure roll 44 integrally with the pressure roll 44 while being accommodated in the concave portion 46 of the pressure roll 44.

[0057] Here, in the conveyance unit 14 of the present embodiment, in a state where the heating roll 92 is located at the separated position, the conveyance unit 14 conveys the recording medium P with the gripper 36 holding the leading end portion of the recording medium P toward the sandwiching position NP. Then, when the conveyance unit 14 conveys the recording medium P to the sandwiching position NP, the conveyance unit 14 releases the holding of the leading end portion of the recording medium P.

[0058] That is, in the conveyance unit 14, the gripper 36 releases the holding of the leading end portion of the recording medium P after passing through the sandwiching position NP. At this time, the pressure roll 44 maintains a rotated state, in other words, a state where the chain 34 is moving in a circumferential motion.

[0059] Further, the fact that the recording medium P has been conveyed to the sandwiching position NP is detected by the detection unit provided upstream in the conveyance direction of the sandwiching position NP based on the time after the detection unit detects the leading end of the recording medium P. Note that the detection target of the detection unit may be the support member 38 or the gripper 36 instead of the leading end of the recording medium P.

[0060] Also, after the gripper 36 has passed through the sandwiching position NP and after the holding of the leading end portion of the recording medium P by the gripper 36 has been released, the heating roll 92 starts to move from the separated position to the contact position and sandwiches the recording medium P conveyed to the sandwiching position NP with the pressure roll 44. Then, with the recording medium P sandwiched between the heating roll 92 and the pressure roll 44, the heating roll 92 starts to rotate to convey the recording medium P.

[0061] Note that the heating roll 92 may start to move from the separated position to the contact position before the holding of the leading end portion of the recording medium P by the gripper 36 is released, as long as the sandwiching of the recording medium P by the heating roll 92 and the pressure roll 44 is completed after the holding of the leading end portion of the recording medium P by the gripper 36 is released.

[0062] In this way, in the fixing device 90, while conveying the recording medium P in a state where the recording medium P is sandwiched between the heating roll 92 and the pressure roll 44, the recording medium P is heated and pressurized to fix the ink image transferred to the recording medium P on the recording medium P.

[0063] (Transfer cylinder) Next, the transfer cylinder 50 will be described.

[0064] As shown in FIGS. 6 and 11, the transfer cylinder 50 as an example of the cylinder member has a cylinder main body 52 and a sheet member 100 wound around the cylinder main body 52. In the following, the axial direction, radial direction, and circumferential direction of the cylinder main body 52 may be simply expressed as the "axial direction", "radial direction", and "circumferential direction".

[0065] Also, hereinafter, the upstream in the rotation direction (arrow B direction) of the transfer cylinder 50 may simply be expressed as "upstream", and the downstream in the rotation direction (arrow B direction) of the transfer cylinder 50 may simply be expressed as "downstream". In addition, when the circumferential direction and the axial direction are used in the description of the sheet member 100, it is the direction in the state where the sheet member 100 is wound around the cylinder main body 52. Further, the direction along the short side of the sheet member 100 having a rectangular shape in plan view is defined as the width direction, and the direction along the long side is defined as the length direction.

[0066] A single recess 54 is formed along the axial direction in a part of the circumferential direction of the cylinder main body 52, and the cross section is substantially circular, specifically, the outer shape of the cross section orthogonal to the axial direction is formed in a substantially circular shape. The recess 54 as an example of the recessed portion has a depth along the radial direction of the cylinder main body 52. Further, the cylinder main body 52 is formed of a metal material such as stainless steel or aluminum. In the present embodiment, the depth direction of the recess 54 coincides with the radial direction. However, it is not necessary for the depth direction and the radial direction to coincide. The depth direction may be inclined by, for example, about 5° to 10° with respect to the radial direction.

[0067] The length of the cylinder main body 52 along its axial direction is formed to be longer than the width of the sheet member 100 along its axial direction, and the sheet member 100 is wound with its central portion in the width direction aligned with the central portion of the cylinder main body 52 in the axial direction. Note that the width of the sheet member 100 is larger than the maximum width of the recording medium P (see FIG. 4).

[0068] Note that "sheet-like" means a shape such as paper or a thin plate, and has a thickness that can be deformed along the outer circumference of the cylinder main body 52. The length of the sheet member 100 in the circumferential direction (length direction) is substantially the same as the length of the cylinder main body 52 in the circumferential direction excluding the recess 54.

[0069] As shown in FIG. 11, the sheet member 100 has a metal layer 150 that contacts and is wound around the outer peripheral surface of the cylinder main body 52, and an outer layer 102 that is laminated and adhered to the outer peripheral surface of the metal layer 150 (see also FIGS. 7 to 10, etc.).

[0070] Note that the metal layer 150 of this embodiment is made of a metal material such as stainless steel, aluminum, and copper. Also, the thickness of the metal layer 150 in this embodiment is, for example, 0.1 mm.

[0071] The outer layer 102 of this embodiment is made of a solid rubber-based material such as nitrile rubber, chloroprene rubber, ethylene propylene diene rubber, acrylonitrile butadiene rubber, and silicone rubber, or a conductive resin material such as polyimide, polyamideimide, polyurethane, polyethylene, and mixtures thereof. Note that the thickness of the outer layer 102 in this embodiment is thicker than that of the metal layer 150 and is, for example, 7.0 mm.

[0072] As shown in FIGS. 6, 7, 10, 11, 12, and 13, a first attachment member 110 is provided at one end 100A in the length direction of the sheet member 100, and a second attachment member 120 is provided at the other end 100B in the length direction of the sheet member 100.

[0073] In this embodiment, the first attachment member 110 is joined to the inner surface of the sheet member 100, that is, the metal layer 150, by an adhesive, double-sided tape, welding, or the like. The first attachment member 110 is in the shape of a plate that is long in the axial direction and has a thickness direction as the radial direction. The first attachment member 110 is made of a metal material such as stainless steel and aluminum.

[0074] As shown in FIG. 12, the first attachment member 110 has a pair of protruding portions 112 that protrude from both sides in the axial direction of the sheet member 100, and a central portion 113 that constitutes the space between the pair of protruding portions 112. The central portion 113 is arranged within the range of the sheet member 100 when viewed in the thickness direction of the sheet member 100, in other words, when viewed in the radial direction. In other words, when viewed in the thickness direction of the sheet member 100, the entire central portion 113 overlaps with the sheet member 100. Note that in this embodiment, the downstream end of the sheet member 100 and the downstream end of the first attachment member 110 overlap when viewed in the thickness direction of the sheet member 100.

[0075] A first through-hole 115 through which a mounting screw 60 (see FIGS. 6, 10, and 11) passes is formed in a pair of protruding portions 112. The first through-hole 115 in the present embodiment has a U-shaped configuration with the other side in the circumferential direction being open.

[0076] Also, as shown in FIGS. 7 and 11, a protruding portion 114 having a triangular shape when viewed from the axial direction protruding on one side is formed at a portion on one side (upstream side) in the circumferential direction of the first attachment member 110 (see also FIG. 10).

[0077] As shown in FIGS. 7 and 12, an end portion 100B of the sheet member 100 has an end portion 152 of a metal layer 150 extending in the circumferential direction from the outer layer 102 (see also FIGS. 10 and 11). A plurality of U-shaped fixing grooves 154, a plurality of second through-holes 200B, a plurality of positioning holes 212B, and a positioning hole 210B are formed at intervals in the axial direction in the end portion 152 of the metal layer 150. Hereinafter, the "end portion 152 of the metal layer 150" may be referred to as the "metal layer end portion 152".

[0078] The second through-hole 200B in the present embodiment has a U-shaped configuration with one side in the circumferential direction being open. The positioning hole 212B is a plurality of elongated holes that are long in the axial direction, and the positioning hole 210B is a round hole and is an example of a fitting portion.

[0079] As shown in FIGS. 6 and 8 to 11, the second attachment member 120 has an axially long plate-shaped fixing plate 124 and a substantially quadrangular prism-shaped fixed portion 122. The metal layer end portion 152 of the other end portion 100B of the sheet member 100 is sandwiched between the fixing plate 124 as an example of a fixing portion and the fixed portion 122, and the two are fastened by a fixing screw 70 (see FIG. 6) passed through the fixing groove 154 (see FIGS. 7 and 12), thereby being fixed to the second attachment member 120.

[0080] As shown in FIGS. 8 to 10, on the fixing plate 124, positioning holes 210A (see FIGS. 8 and 10), positioning holes 212A (see FIG. 9), second through holes 200A, and guide holes 220A are formed side by side at intervals in the axial direction. On the fixed part 122, second through holes 200C and guide holes 220C are formed side by side at intervals in the axial direction. Further, on the fixed part 122, positioning pins 211 (FIGS. 8 and 10) and positioning pins 213 (see FIG. 9) that protrude outward in the depth direction are provided (see also FIG. 6).

[0081] Then, in a state where the metal layer end portion 152 is sandwiched between the fixing plate 124 and the fixed part 122 and fastened by the fixing screw 70, the second through holes 200A, second through holes 200B, and second through holes 200C are formed at the same position and with substantially the same size, and these overlap. Similarly, the guide holes 220A and guide holes 220C are formed at the same position and with substantially the same size, and these overlap. Note that the guide holes 220A and guide holes 220C are formed along the radial direction, and the cross-sectional shape is circular.

[0082] Also, in a state where the metal layer end portion 152 is sandwiched between the fixing plate 124 and the fixed part 122 and fastened by the fixing screw 70, the positioning holes 210A, 212A and the positioning holes 210B, 212B are formed at the same position and with substantially the same size, and these overlap.

[0083] As shown in FIG. 9, the positioning pin 213 is formed at the same position as the positioning holes 212A, 212B and passes through them. Also, as shown in FIGS. 8 and 10, the positioning pin 211 is formed at the same position as the positioning holes 210A, 210B and is fitted into them. Thereby, the metal layer end portion 152 is positioned with respect to the second attachment member 120 in the circumferential direction and the axial direction.

[0084] As shown in FIGS. 11 and 13, on one circumferential side (upstream side) within the recess 54 of the body main body 52, a first pedestal portion 300 to which a first attachment member 110 of one end portion 100A of the sheet member 100 is attached is provided (see also FIGS. 6 and 10). The first pedestal portion 300 is configured to have a main body portion 310 and a wall portion 320 joined to one side of the main body portion 310 (see also FIG. 10). As shown in FIG. 10, the main body portion 310 projects axially outward from the wall portion 320. As shown in FIGS. 11 and 13, the wall portion 320 extends radially outward from a contact surface 310A of the main body portion 310 described later.

[0085] The main body portion 310 constituting the first pedestal portion 300 has a contact surface 310A that contacts an attachment surface 110A (see also FIG. 12) inside the first attachment member 110 in the radial direction. The wall portion 320 has a contact surface 320A against which an inclined surface 114A of a protruding portion 114 (see also FIGS. 6 and 10) on the circumferential downstream side of the first attachment member 110 abuts. The contact surface 320A is inclined toward the other side in the radial outward direction. In other words, on one circumferential side of the first pedestal portion 300, a recess 302 is formed as an example of a positioning portion having a triangular cross-sectional shape when viewed from the axial direction.

[0086] As shown in FIGS. 6 and 10, both axial ends of the main body portion 310 of the first pedestal portion 300 provided in the recess 54 of the body main body 52 are screwed with attachment screws 60 passed through first through holes 115 formed in overhanging portions 112 (see also FIGS. 7 and 12) of the first attachment member 110, whereby one end portion 100A of the sheet member 100 is attached to the first pedestal portion 300 provided in the recess 54.

[0087] At this time, as shown in FIGS. 11 and 13, the attachment surface 110A of the first attachment member 110 is in contact with the contact surface 310A of the first pedestal portion 300. Further, the protruding portion 114 of the first attachment member 110 is inserted into the recess 302 and abutted in the circumferential direction, and the inclined surface 114A abuts against the contact surface 320A.

[0088] Note that the first mounting member 110 can be removed from the first base portion 300 by removing the mounting screw 60. Further, as described above, the first through hole 115 in the present embodiment has a U-shaped configuration with the other side in the circumferential direction being open. Therefore, when the mounting screw 60 passed through the first through hole 115 is loosened, the first mounting member 110 can move relative to the other side (downstream side) in the circumferential direction.

[0089] As shown in FIGS. 6 and 8 to 11, on the other side (downstream side) in the circumferential direction within the recess 54 of the cylinder main body 52, a second base portion 350 to which the second mounting member 120 of the other end portion 100B of the sheet member 100 is attached is provided.

[0090] In the present embodiment, the second base portion 350 is joined to a support portion 640 (see FIGS. 9 and 11) provided in the recess 54. The second base portion 350 has an L-shaped configuration when viewed from the axial direction, and a guide pin 352 protruding radially outward is provided on the second base portion 350. As shown in FIG. 6, the guide pins 352 are provided on both sides in the axial direction (see also FIGS. 8 and 9).

[0091] Then, the guide pins 352 of the second base portion 350 provided in the recess 54 of the cylinder main body 52 are passed through the guide holes 220A and 220C (see FIGS. 8 to 10) of the second mounting member 120, so that the second mounting member 120 is positioned in the circumferential direction and the axial direction so as to be movable in the radial direction.

[0092] Further, a tension applying screw 72 (see FIG. 6), which is an example of a tension applying mechanism, passed through the second through holes 200A, 200B, and 200C is screwed into the second base portion 350, so that the second mounting member 120 moves along the guide pins 352 and the guide holes 220A and 220C in the depth direction and is fixed. As a result, the metal layer end portion 152 of the sheet member 100 is pulled in the depth direction, tension is applied to the metal layer 150, and the second mounting member 120 is attached to the second base portion 350. Note that the head portion 72A (see FIG. 6) of the tension applying screw 72 is larger than the second through holes 200A, 200B, and 200C.

[0093] Note that the second attachment member 120 can be removed from the second base portion 350 by removing the tension-applying screw 72. Further, as described above, the second through holes 200A, 200B, and 200C in the present embodiment are U-shaped with one side in the circumferential direction being open. Therefore, when the tension-applying screw 72 passed through the second through holes 200A, 200B, and 200C is loosened, the second attachment member 120 can move relative to the other side in the circumferential direction.

[0094] As shown in FIGS. 10 and 12, in the sheet member 100 of the present embodiment, the axial center position of the first through hole 115 of the first attachment member 110 is formed at a position at a distance L from the axial center position of the positioning hole 210B formed at the end portion 152 of the metal layer. That is, the axial center position of the first through hole 115 of the first attachment member 110 is set based on the axial center position of the positioning hole 210B formed at the end portion 152 of the metal layer.

[0095] (Operation according to the present embodiment) Next, the operation of the present embodiment will be described.

[0096] The tension-applying screw 72 passed through the second through holes 200A, 200B, and 200C of the second attachment member 120 provided at the other end portion 100B of the sheet member 100 is screwed into the second base portion 350 provided in the recess 54 of the body main body 52, so that the second attachment member 120 moves and is fixed in the depth direction along the guide pin 352 and the guide holes 220A and 220C. As a result, the end portion 152 of the metal layer of the sheet member 100 is pulled in the depth direction, and tension is applied to the metal layer 150. Then, by applying tension to the metal layer 150, the sheet member 100 adheres closely to the body main body 52.

[0097] At this time, the end portion 152 of the metal layer of the other end portion 110B of the sheet member 100 has the positioning pin 213 passed through the long positioning holes 212A and 212B that are long in the axial direction, and the positioning pin 211 is fitted into the circular positioning holes 210A and 210B. As a result, the end portion 152 of the metal layer is positioned in the circumferential direction and the axial direction with respect to the second attachment member 120.

[0098] Therefore, compared with the case where the metal layer end portion 152 of the other end portion 110B of the sheet member 100 is free to move along the circumferential surface and the axial direction of the body main body 52, the adhesion of the sheet member to the body main body is improved.

[0099] In addition, the tension applied to the metal layer 150 of the sheet member 100 can be adjusted by the amount of screwing of the tension applying screw 72.

[0100] Further, the guide pins 352 of the second pedestal portion 350 provided in the recess 54 of the body main body 52 are passed through the guide holes 220A and 220C of the second attachment member 120, so that the second attachment member 120 is movable in the depth direction (radial direction) and is positioned with respect to the circumferential direction and the axial direction.

[0101] Therefore, compared with the case where the second attachment member 120 is not positioned so as to be movable in the depth direction, the adhesion of the sheet member 100 to the body main body 52 is improved.

[0102] The metal layer end portion 152 of the other end portion 100B of the sheet member 100 is sandwiched between the fixed plate 124 and the fixed portion 122 of the second attachment member 120, and the two are fastened by a fixing screw 70 (see FIG. 6) passed through the fixing groove 154, so that the metal layer end portion 152 is fixed to the second attachment member 120.

[0103] Therefore, compared with the case where the metal layer end portion 152 is adhered and fixed to the second attachment member 120, a large tension can be applied to the metal layer end portion 152, and as a result, the adhesion of the sheet member 100 to the body main body 52 is improved.

[0104] The axial center position of the first through hole 115 of the first attachment member 110 provided at one end portion 100A of the sheet member 100 is formed at a position at a distance L from the axial center position of the positioning hole 210B formed in the metal layer end portion 152 of the other end portion 110B. That is, the axial center position of the first through hole 115 of the first attachment member 110 is defined based on the axial center position of the positioning hole 210B formed in the metal layer end portion 152.

[0105] Therefore, compared with the case where the position of the first through hole 115 of the first attachment member 110 is defined based on the axial end of the sheet member 100, the attachment accuracy of the first attachment member 110 is improved.

[0106] Further, both axial ends of the main body portion 310 of the first pedestal portion 300 provided in the recess 54 of the body main body 52 are screwed with mounting screws 60 passed through the first through holes 115 formed in the protruding portions 112 of the first attachment member 110 at one end 100A of the sheet member 100, whereby one end 100A of the sheet member 100 is attached to the first pedestal portion 300 provided in the recess 54.

[0107] Therefore, compared with the case where only the central portion 113 in the axial direction of the first attachment member 110 is fastened to the first pedestal portion 300 with screws, the lifting on both sides in the axial direction at one end 100A of the sheet member 100 is suppressed.

[0108] The first attachment member 110 provided at one end 100A of the sheet member 100 has a pair of protruding portions 112 protruding axially from both sides of the sheet member 100 and a central portion 113 constituting between the pair of protruding portions 112. The central portion 113 is arranged within the range of the sheet member 100 when viewed in the thickness direction of the sheet member 100, in other words, when viewed in the radial direction. In other words, the entire central portion 113 overlaps the sheet member 100 when viewed in the thickness direction of the sheet member 100.

[0109] Therefore, compared with the case where the central portion 113 of the first attachment member 110 protrudes from one end 100A of the sheet member 100, the range along the circumferential direction of the sheet member 100 disposed on the body main body 52 can be increased.

[0110] Further, the protruding portion 114 of the first attachment member 110 provided at one end 100A of the sheet member 100 is inserted into the recess 302 and abutted, and the inclined surface 114A abuts against the abutting surface 320A.

[0111] Therefore, compared with the case where the first attachment member 110 is freely movable in the circumferential direction, the inclination of the sheet member 100 with respect to the body main body 52 is suppressed. Further, compared with the case where the first attachment member 110 is freely movable radially outward of the body main body 52, the lifting of one end portion 100A of the sheet member 100 from the body main body 52 is suppressed.

[0112] In the image forming apparatus 10 of the present embodiment, the metal layer end portion 152 of the other end portion 110B of the sheet member 100 constituting the transfer member 40 is positioned with respect to the second attachment member 120 in the circumferential direction and the axial direction.

[0113] Therefore, compared with the case where the metal layer end portion 152 of the other end portion 110B of the sheet member 100 is freely movable along the circumferential surface and the axial direction of the body main body 52, the adhesion of the sheet member 100 to the body main body 52 is improved, so that the occurrence of image quality defects in the ink image transferred to the recording medium P is suppressed.

[0114] (Another image forming apparatus) The image forming apparatus 10 according to the present embodiment is not limited to the inkjet type as described above, and may be, for example, an electrophotographic type as shown in FIG. 5. That is, instead of the adhesive layer forming device 26, the particle supply device 18, and the discharge head 20, a toner image forming unit 80 that forms a toner image (an example of an image) of each color may be provided.

[0115] The toner image forming units 80 (80Y, 80M, 80C, 80K) of each color each have a columnar photosensitive member 82 that rotates in one direction (arrow B direction), and around each photosensitive member 82, in order from the upstream side in the rotation direction of the photosensitive member 82, a charger 84, an exposure device 86, and a developing device 88 are arranged.

[0116] In each color toner image forming unit 80, a charger 84 charges the surface of a photoreceptor 82, and an exposure device 86 exposes the surface of the photoreceptor 82 charged by the charger 84 to form an electrostatic latent image on the surface of the photoreceptor 82. Then, a developing device 88 develops the electrostatic latent image formed on the surface of the photoreceptor 82 by the exposure device 86 to form a toner image.

[0117] Note that on the inner peripheral surface side of the transfer belt 30, a primary transfer roll 78 is provided facing each photoreceptor 82 with the transfer belt 30 interposed therebetween. The toner images formed by the respective color toner image forming units 80 are sequentially primary transferred and superimposed on the transfer belt 30 at a primary transfer position T1 where the primary transfer roll 78 is provided, and the superimposed toner images are secondary transferred to a recording medium P at a secondary transfer position T2.

[0118] (Others) Note that the present invention is not limited to the above-described embodiments, and can be appropriately designed and changed within a range not departing from the gist of the present invention.

[0119] For example, in the above-described embodiment, the tension applying means is the tension applying screw 72, but the present invention is not limited thereto. For example, the second attachment member 120 may be attached to the second base portion 350 with a patch lock. Alternatively, the second attachment member 120 may be configured to be pulled in the depth direction by a tension spring or the like.

[0120] Note that a patch lock is a fastener of a mechanism that fixes two members by hooking and tipping a lever or the like provided on one member onto a protrusion or the like provided on the other member.

[0121] Also, for example, in the above-described embodiment, the metal layer end portion 152 of the other end portion 110B of the sheet member 100 is positioned by fitting the positioning pins 211 into the circular positioning holes 210A and 210B, but the present invention is not limited thereto. For example, a convex portion may be provided on the metal layer end portion 152, and a hole or the like into which the convex portion fits may be provided on the second attachment member 120.

[0122] Further, for example, in the above-described embodiment, the guide pins 352 provided on the second base portion 350 were passed through the guide holes 220A and 220C of the second attachment member 120, but the present invention is not limited thereto. Guide pins may be provided on the second attachment member 120, and guide holes may be provided on the second base portion 350.

[0123] Further, for example, in the sheet member 100, the outer layer 102 is adhered to the metal layer 150 by an adhesive, but the present invention is not limited thereto. For example, the inner peripheral surface of the outer layer 102 that contacts the outer peripheral surface of the metal layer 150 may be heated and melted to be adhered. Further, a coating layer (not shown) may be provided on the outer peripheral surface of the outer layer 102. Further, the coating layer is not limited to a single layer, and may be composed of a plurality of layers.

[0124] Further, for example, in the above-described embodiment, the metal layer end portion 152 is sandwiched between the fixing plate 124 and the portion to be fixed 122 and fixed to the second attachment member 120 by tightening with the fixing screw 70, but the present invention is not limited thereto. For example, the metal layer end portion 152 may be joined to the second attachment member 120 with an adhesive or the like.

[0125] Further, for example, in the above-described embodiment, the pair of protruding portions 112 that protrude from the sheet member 100 in the axial direction on both sides of the first attachment member 110 were attached to the first base portion 300, but the present invention is not limited thereto. For example, a configuration may be such that only the protruding portion that protrudes in the circumferential direction from one end of the sheet member 100 is attached to the first base portion 300. Alternatively, the central portion 113 may protrude in the circumferential direction, and the protruding portion may be attached to the first base portion 300.

[0126] Further, in the above-described embodiment, the central portion 113 of the first attachment member 110 was arranged within the range of the sheet member 100 in the thickness direction view (radial direction view) of the sheet member 100, but the present invention is not limited thereto. For example, the central portion 113 of the first attachment member 110 may have a configuration that protrudes in the circumferential direction from one end of the sheet member 100.

[0127] In addition, in the above-described embodiment, the first attachment member 110 was joined to the metal layer 150 at one end portion 100A of the sheet member 100, but it is not limited thereto. For example, it may be fixed to the one end portion 100A with a screw or the like.

[0128] Further, the body main body 52 may be formed in a substantially cylindrical shape instead of a substantially cylindrical shape. Further, the body member is not limited to the configuration applied to the transfer cylinder 50, and may be applied to, for example, a fixing cylinder for pressure-fixing toner, a blanket cylinder used in offset printing, and the like. Further, in the present embodiment, a toner image is cited as an example of an image, and the toner image is formed by a dry electrophotographic method, but it is not limited thereto. For example, a toner image formed by a wet electrophotographic method may be used.

Explanation of reference numerals

[0129] 10 Image forming apparatus 12 Image forming unit 50 Transfer cylinder (an example of a body member) 52 Body main body 54 Concave portion (an example of a recessed portion) 60 Mounting screw 70 Fixing screw 72 Tension applying screw (an example of a tension applying mechanism) 72A Head 80 Toner image forming unit (an example of an image forming unit) 100 Sheet member 100A One end portion 100B The other end portion 102 Outer layer 110 First attachment member 110A Attachment surface 112 Overhanging portion 113 Central portion 114 Protrusion 115 First through hole 120 Second attachment member 122 Fixed portion 124 Fixing plate (an example of a fixing portion) 150 Metal layer 152 End portion of the metal layer Second through-hole 200A Second through-hole 200B Second through-hole 200C Positioning hole 210B (an example of a fitting part) Positioning pin 211 (an example of a convex part) Guide hole 220A Guide hole 220C First base part 300 Recess 302 (an example of a positioning part) Contact surface 310A Second base part 350 Guide pin 352 P recording medium

Claims

1. A body main body having a recessed portion along the axial direction and having a substantially circular cross-sectional shape, A sheet member having a metal layer wound around the body main body and in contact with the body main body, and an outer layer laminated on the metal layer, A first attachment member provided at one end of the sheet member and removably attached to one side in the circumferential direction in the recessed portion, A second attachment member provided at an end of the metal layer protruding in the circumferential direction from the outer layer at the other end of the sheet member and removably attached to the other side in the circumferential direction in the recessed portion, A tension applying mechanism that pulls the second attachment member in the depth direction of the recessed portion to apply tension to the metal layer, A convex portion provided on one of the second attachment member and the end of the metal layer, A fitting portion provided on the other of the second attachment member and the end of the metal layer and into which the convex portion fits, and comprising The tension applying mechanism A second pedestal provided on the other side in the circumferential direction in the recessed portion, A guide pin protruding in the depth direction of the recessed portion from one of the second pedestal and the second attachment member and passed through a guide hole formed in the other of the second pedestal and the second attachment member, Fixing means for fixing the second attachment member to the second pedestal, and having A body member.

2. The fixing means is a screw, The screw passes through a second through hole formed in the second attachment member and smaller than the head of the screw, and the tip end is screwed into the second pedestal, The body member according to claim 1.

3. The second attachment member has a fixing portion and a fixed portion in which the second through hole and the guide hole are formed and which are fastened with a screw, The end of the metal layer is sandwiched between the fixing portion and the fixed portion, The body member according to claim 2.

4. On one side in the circumferential direction in the recessed portion, a first base portion is provided to which the first attachment member is attached by a screw passed through a first through-hole formed in the first attachment member and smaller than the head. The position of the first through-hole of the first attachment member along the axial direction of the body main body is defined based on the convex portion or the fitting portion provided on the second attachment member. The body member according to any one of claims 1 to 3.

5. The first attachment member has an overhanging portion having a pair of overhanging portions that project from the sheet member to both sides in the axial direction of the body main body. The first through-hole is formed in the overhanging portion. The body member according to claim 4.

6. The first attachment member has a pair of the overhanging portions, and a central portion disposed between the pair of the overhanging portions, and has The central portion is disposed within the range of the sheet member when viewed in the thickness direction of the sheet member. The body member according to claim 5.

7. The first base portion is provided with a positioning portion that abuts against the first attachment member in the circumferential direction to position it. The body member according to any one of claims 4 to 6.

8. The positioning portion restricts the movement of the first attachment member outward in the radial direction of the body main body by abutting against the first attachment member in the radial direction of the body main body in a state where the first attachment member is abutted in the circumferential direction. The body member according to claim 7.

9. The body member according to any one of claims 1 to 8 for conveying a recording medium, and an image forming unit that forms an image on the recording medium conveyed by the body member. An image forming apparatus comprising the same.

Images