Transfer apparatus, image forming apparatus

Abstract

To provide a transfer device that prevents interference of a latent image carrier unit with a transfer device, and allows the latent image carrier unit to be removed with a simple method.SOLUTION: A transfer device 20 comprises: a detection sensor 22 that is provided on a PCDU 10 in a contactable and separable manner; a contact and separation mechanism that brings the detection sensor 22 into contact with the PCDU 10 and separates the detection sensor from the PCDU; a regulation member 72; and a release lever 71. The PCDU 10 is removably attached to an image forming apparatus 1. The regulation member 72 regulates the removal of the PCDU 10 from the body of the image forming apparatus 1. Operation of the release lever 71 causes the contact and separation mechanism to separate the detection sensor 22 from the PCDU 10, and releases the regulation of removal of the PCDU 10 from the image forming apparatus 1 performed by the regulation member 72.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a transfer device and an image forming apparatus provided with the transfer device. [Background Art]

[0002] There is known an image forming apparatus in which a latent image carrier unit including a photoconductor or the like is detachably attached to the image forming apparatus.

[0003] The latent image carrier unit and a transfer device including an intermediate transfer belt or the like are disposed close to each other in the image forming apparatus. For this reason, in order to prevent a member provided on the transfer device from interfering with the latent image carrier unit when the latent image carrier unit is attached to or detached from the image forming apparatus, there is known a configuration provided with a mechanism that moves the member toward and away from the latent image carrier unit.

[0004] For example, in the image forming apparatus disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 2018-13503), the intermediate transfer belt can be moved in a direction away from the secondary transfer roller and the photoconductor by operating an unlocking operation section. Further, pressing down the unlocking operation section causes a second operation section for pulling out the image forming unit to appear. When the image forming unit is pulled out halfway by the second operation section, a third operation section appears. The image forming apparatus is also provided with a falling-off prevention claw that interrupts pulling-out of the image forming unit halfway. The third operation section is provided with a release mechanism that releases the restriction by the falling-off prevention claw.

[0005] In the configuration of Patent Document 1, the intermediate transfer belt can be separated before the image forming unit is pulled out, and interference between the image forming unit and the transfer device when pulling out the image forming unit can be prevented. However, there has been a problem that a plurality of procedures are required before pulling out the image forming unit, which makes the work complicated. [Summary of the Invention] [Problem to be Solved by the Invention]

[0006] The objective is to provide a transfer device that prevents interference between the latent image carrier unit and the transfer device, and that allows the latent image carrier unit to be removed by a simple method. [Means for solving the problem]

[0007] To solve the above problems, the present invention provides A transfer belt and provided on the inside of the transfer belt, A transfer apparatus comprising: a connecting / separating portion provided to be able to move toward and away from a latent image carrier unit; a connecting / separating mechanism for moving the connecting / separating portion toward and away from the latent image carrier unit; a restricting member; and an operating member, wherein the restricting member restricts the removal of the latent image carrier unit from the image forming apparatus, and operation of the operating member causes the connecting / separating mechanism to separate the connecting / separating portion from the latent image carrier unit, and releases the restriction by the restricting member on the removal of the latent image carrier unit from the image forming apparatus. [Effects of the Invention]

[0008] According to the present invention, interference between the latent image carrier unit and the transfer device is prevented, and the latent image carrier unit can be removed by a simple method. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic diagram of the image forming apparatus. [Figure 2] This diagram shows the configuration around the release lever, and is a front view of the lever in the restricted position. [Figure 3] This diagram shows the configuration around the release lever, and is a front view of the lever in the release position. [Figure 4] This is a perspective view of the area around the release lever with the inner cover removed, showing the lever in the restricted position. [Figure 5] This is a perspective view of the area around the release lever with the inner cover removed, showing the lever in the release position. [Figure 6] This is a front view of the restricted state with the release lever removed. [Figure 7] It is a front view in a released state where the release lever is removed. [Figure 8] It is a perspective view showing a lever fixing shaft and first to fourth link members. [Figure 9] It is an exploded perspective view of the first to fourth link members. [Figure 10] It is a front view in a regulated state showing the operation of the first to fifth link members. [Figure 11] It is a front view showing the operation of the first to fifth link members, which is a diagram in the middle of transition from the regulated state to the released state. [Figure 12] It is a front view in the released state showing the operation of the first to fifth link members. [Figure 13] It is a rear view showing the configuration around the most downstream primary transfer portion in the regulated state, and is also a diagram showing the "contact" state. [Figure 14] It is a rear view showing the configuration around the most downstream primary transfer portion in the released state. [Figure 15] It is a diagram showing a configuration that regulates the rotation range of a fifth link member. [Figure 16] It is a perspective view of a regulating member viewed from the front side. [Figure 17] It is a perspective view of a regulating member viewed from the rear side. [Figure 18] It is an exploded perspective view of the regulating member. [Figure 19] It is a schematic configuration diagram of a transfer device, where Figure (a) is a diagram showing a state where each primary transfer portion is in contact, and Figure (b) is a diagram showing a state where the most downstream primary transfer portion is separated. [Figure 20] It is a perspective view showing a cam member. [Figure 21] It is a perspective view of the cam member and the surrounding configuration viewed from the rear side. [Figure 22] It is a diagram of the contacting / separating configuration for the intermediate transfer belt of the most downstream primary transfer portion viewed from the rear side of the image forming apparatus, and is a diagram showing the "separated" state. [Figure 23] It is a plan view showing the configuration around the first arm and the second arm. [Figure 24] It is a perspective view showing the second arm and the surrounding configuration. [Figure 25] It is a perspective view showing the configuration of the second arm and its periphery as seen from the back side. [Figure 26] It is a plan view showing the contact and separation configuration of the detection sensor and the sensor bracket. [Figure 27] It is a plan view showing a positioning state of the second sensor bracket in the "separated" state. [Figure 28] It is a plan view showing the contact and separation configuration of the central primary transfer unit and the most upstream primary transfer portion with respect to the intermediate transfer belt. MODE FOR CARRYING OUT THE INVENTION

[0010] Hereinafter, embodiments according to the present invention will be described with reference to the drawings. In each drawing, the same or corresponding parts are denoted by the same reference numerals, and repeated description thereof will be appropriately simplified or omitted.

[0011] FIG. 1 is a diagram showing the configuration of an image forming apparatus 1 according to an embodiment of the present invention. The image forming apparatus 1 shown in FIG. 1 is a color printer of tandem configuration in which a plurality of photoconductors as latent image carriers are arranged in parallel. Each photoconductor can form a toner image of a color corresponding to color separation using toner as a developer supplied from a developing device. After the toner images formed on the respective photoconductors are superimposed and transferred onto an intermediate transfer member, the superimposed image is collectively transferred onto a sheet as a recording medium, whereby a multicolor image can be formed on the sheet. In the present invention, it goes without saying that the image forming apparatus is not limited to a color printer, and also includes a color copying machine, a facsimile machine, a printing press, and the like.

[0012] In FIG. 1, in the image forming apparatus 1, an image forming section 1A is arranged near the center in the vertical direction, a paper feeding section 1B is arranged below the image forming section 1A, and a document scanning section 1C including a document placing table 1C1 is arranged above the image forming section 1A. In the image forming section 1A, an intermediate transfer belt 2 as an intermediate transfer member or a belt member is arranged. The intermediate transfer belt 2 has an extending surface in the horizontal direction. Above the intermediate transfer belt 2, a configuration for forming an image of a color having a complementary color relationship with color separation colors is provided.

[0013] The image forming unit 1A is provided with multiple PCDU10 (Photo Conductor Development Units), which are latent image carrying units. Each PCDU10K, 10C, 10M, 10Y, and 10T can form images using complementary color toners (yellow, magenta, cyan, and black) and glossy images using transparent toner. Each PCDU10K, 10C, 10M, 10Y, and 10T has photoreceptors 3K, 3C, 3M, 3Y, and 3T (transparent toners) capable of carrying images arranged side by side along the tensioned surface of the intermediate transfer belt 2. In the following description, if the content is common to all photoreceptors, the photoreceptor will be indicated by reference numeral 3. Also, PCDU10K, 10C, 10M, 10Y, and 10T will also be referred to as PCDU10. Each PCDU10 includes at least one photoreceptor 3 and, in this embodiment, includes a developing device and the like.

[0014] Each photoreceptor 3K, 3C, 3M, 3Y, and 3T consists of a drum that can rotate in the same direction (counterclockwise in Figure 1), and around it are a charging device, a writing device 5, a developing device 6, a primary transfer roller 7 as a transfer member, and a cleaning device that perform image formation processing during the rotation process (for convenience, the reference numeral T is added to the symbols of each device, with photoreceptor 3T as the target).

[0015] The transfer device 20 comprises an intermediate transfer belt 2, a plurality of primary transfer rollers 7 (for convenience, only the primary transfer roller 7T is shown with a reference numeral), and a plurality of rollers 2A to 2C, which serve as transfer members.

[0016] The intermediate transfer belt 2 sequentially transfers toner images from the PCDU 10, each equipped with a photoreceptor 3. The intermediate transfer belt 2 is wrapped around multiple rollers 2A to 2C, and multiple rollers not indicated in Figure 1, allowing it to travel in a circular motion in the direction of the arrows in Figure 1. Rollers 2A and 2B tension the intermediate transfer belt 2 on both sides of the outer side in the direction of travel of the intermediate transfer belt 2, at opposing positions facing each photoreceptor 3 of the intermediate transfer belt 2. The secondary transfer opposing roller 2C faces the secondary transfer device 9 across the intermediate transfer belt 2.

[0017] The secondary transfer device 9 has a secondary transfer roller 9A. The secondary transfer roller 9A forms a secondary transfer nip between itself and the secondary transfer opposing roller 2C, with the intermediate transfer belt 2 in between. The secondary transfer opposing roller 2C is subjected to a secondary transfer bias of the same polarity as the toner, while the secondary transfer roller 9A is grounded. As a result, a secondary transfer electric field is formed in the secondary transfer nip that electrostatically moves the multi-color toner image on the intermediate transfer belt 2 from the belt side towards the secondary transfer roller 9A side. This secondary transfer nip transfers the multi-color toner image to the paper that has been transported to the secondary transfer nip.

[0018] Paper, to be used as a recording medium, is fed from the paper feeding unit 1B to the secondary transfer position. The paper feeding unit 1B comprises multiple paper feed cassettes 1B1 and multiple transport rollers 1B2. The multiple transport rollers 1B2 are arranged in the transport path for the paper fed from the paper feed cassettes 1B1.

[0019] The writing device 5 irradiates the photoreceptors 3K, 3C, 3M, 3Y, and 3T with writing light, forming an electrostatic latent image on the photoreceptors 3K, 3C, 3M, 3Y, and 3T corresponding to the image information. This image information is obtained by scanning the original document on the original document tray 1C1 of the original document scanning unit 1C, or from image information output from a computer.

[0020] The document scanning unit 1C is equipped with a scanner 1C2 and an automatic document feeder 1C3. The scanner 1C2 exposes and scans the document on the document tray 1C1. The automatic document feeder 1C3 is positioned on the upper surface of the document tray 1C1. The automatic document feeder 1C3 is configured to be able to flip the document as it is fed onto the document tray 1C1, allowing scanning of both the front and back sides of the document.

[0021] The electrostatic latent image formed on the photoreceptor 3 by the writing device 5 is processed into a visible image by the developing device 6 (indicated by the symbol 6T in Figure 1 for convenience) and primary transferred to the intermediate transfer belt 2. Once the toner images of each color are superimposed and transferred onto the intermediate transfer belt 2, they are collectively secondary transferred to the paper by the secondary transfer device 9.

[0022] The paper that has been secondarily transferred has the unfixed image on its surface fixed by the fixing device 11. The fixing device 11 has a belt fixing structure that includes a fixing belt heated by a heating roller and a pressure roller that is in contact with the fixing belt. By providing a contact area between the fixing belt and the pressure roller, i.e., a nip area, the heating area on the paper can be expanded compared to a hot roller fixing method.

[0023] The paper that has passed through the fuser 11 has its transport direction switched by a transport path switching claw located behind the fuser 11. Specifically, the transport path switching claw selects the transport direction to either the transport path toward the paper discharge section 13 or the reverse transport path RP.

[0024] In the image forming apparatus 1 having the above configuration, an electrostatic latent image is formed on a uniformly charged photoreceptor 3 by exposure scanning of a document placed on the document tray 1C1, or by image information from a computer. After the electrostatic latent image is processed into a visible image by the developing device 6, the toner image is first transferred to the intermediate transfer belt 2. The above-mentioned PCDU, writing device 5, transfer device 20, secondary transfer device 9, fixing device 11, etc. constitute the image forming unit that forms the image.

[0025] The toner image transferred to the intermediate transfer belt 2 is transferred directly to the paper fed from the paper feed unit 1B in the case of a single-color image, and in the case of a multi-color image, the primary transfer is repeated to superimpose the images before being transferred to the paper all at once in a secondary transfer. After the secondary transfer, the unfixed image on the paper is fixed by the fuser unit 11, and then fed to the paper discharge unit 13 or inverted and fed again towards the secondary transfer position.

[0026] In Figure 1, the intermediate transfer belt 2 is constructed by forming a single or multiple layer of PVDF (vinyldenine fluoride), ETFE (ethylene-tetrafluoroethylene copolymer), PI (polyimide), PC (polycarbonate), etc., with conductive materials such as carbon black dispersed within it. The volume resistivity of the intermediate transfer belt 2 is set to 108 ~10 12 Ωcm, and surface resistivity of 10 9 ~10 13 The resistance is adjusted to be within the range of Ωcm. A release layer may be coated onto the surface of the intermediate transfer belt 2 as needed. Suitable coating materials include, but are not limited to, fluororesins such as ETFE (ethylene-tetrafluoroethylene copolymer), PTFE (polytetrafluoroethylene), PVDF (vinyldenide fluoride), PEA (perfluoroalkoxy fluororesin), FEP (tetrafluoroethylene-hexafluoropropylene copolymer), and PVF (vinyl fluoride). The intermediate transfer belt 2 can be manufactured by casting, centrifugal molding, etc., and its surface may be polished as needed. If the volume resistivity of the intermediate transfer belt 2 exceeds the above-mentioned range, the bias required for transfer becomes higher, leading to increased power costs, which is undesirable. Furthermore, the charge potential of the intermediate transfer belt 2 increases during the transfer process and transfer paper peeling process, and self-discharge becomes difficult, necessitating the provision of static elimination means. Furthermore, if the volume resistivity and surface resistivity fall below the above range, the charge potential decays more quickly, which is advantageous for static discharge, but the current during transfer flows in the surface direction, causing toner to splatter. Therefore, it is preferable that the volume resistivity and surface resistivity of the intermediate transfer belt 2 in this embodiment are within the above range. The volume resistivity and surface resistivity were measured by connecting an HRS probe (inner electrode diameter 5.9 mm, ring electrode inner diameter 11 mm) to a high-resistivity resistivity meter (Mitsubishi Chemical Corporation: High Resista IP), applying a voltage of 100 V (500 V for surface resistivity) to both sides of the intermediate transfer belt 2, and using the measured values ​​after 10 seconds.

[0027] The intermediate transfer belt 2 is wrapped around at least one pair of rollers, rollers 2A and 2B, and a secondary transfer opposing roller 2C located at the secondary transfer position. By setting the drive roller 2A to rotate clockwise, the intermediate transfer belt 2 can move in the direction of the arrow shown inside the intermediate transfer belt 2 in Figure 1. The transfer surface of the belt moving between rollers 2A and 2B faces the photoreceptors 3K, 3Y, 3C, 3M, and 3T of each imaging unit. At positions facing each photoreceptor across the intermediate transfer belt 2, primary transfer rollers 7 (indicated by the symbol 7T in Figure 1, referring to special toner) are positioned, which correspond to transfer members for electrostatically transferring the visible image on the photoreceptor.

[0028] The primary transfer roller 7 used in this embodiment is made by coating a foaming resin agent onto a metal core (iron, stainless steel, aluminum alloy, etc.). The thickness of the foaming resin agent is 2 mm to 10 mm. Known blade-shaped or brush-shaped transfer members can also be used.

[0029] In this embodiment, in addition to the toner used for full-color image formation, white toner is used to form a white background on the image. Alternatively, transparent toner may be used to improve the gloss and transferability of the image, and light cyan toner, light magenta toner, etc., may be selected to increase the color gamut. In some cases, metallic toners such as gold toner or silver toner may be used as a background to create colored metallic colors such as reddish-bronze or bronze.

[0030] As shown in Figure 2, the PCDU 10 is positioned above the transfer device 20. The PCDU 10 can be attached to and detached from the image forming apparatus body by moving it in the direction perpendicular to the plane of the paper in Figure 2.

[0031] The detection sensor 22, provided on the transfer device 20, is positioned to interfere with the PCDU 10 during the removal operation of the PCDU 10. Therefore, when attaching or detaching the PCDU 10, the detection sensor 22 is moved away from the PCDU 10. Thus, the detection sensor 22 is a contact / separation part provided on the transfer device 20 that moves toward and toward the PCDU 10. The direction of moving away from the PCDU 10 is the direction of arrow C1 in Figure 2, and the direction of moving toward the PCDU 10 is the direction of arrow C2 in Figure 2.

[0032] The transfer device 20 has a restricting member 72. The restricting member 72 in Figure 2 is positioned to interfere with the PCDU 10 during the removal operation of the PCDU 10. That is, it is positioned to overlap with the PCDU 10 on the plane of Figure 2, which is perpendicular to the removal direction of the PCDU 10. By interfering with the PCDU 10, the restricting member 72 restricts the movement of the PCDU 10 in the direction towards the front of the plane of Figure 2, which is the removal direction of the PCDU 10 from the image forming apparatus.

[0033] A release lever 71 is provided on the inner cover 20A, which is part of the transfer frame. The release lever 71 is an operating member used to move the detection sensor 22 toward or toward the PCDU 10, and to switch the presence or absence of the restricting state of the restricting member 72 toward the PCDU 10.

[0034] The release lever 71 has a lever portion 71a as an operating part. The lever portion 71a can be rotated in a first direction B1, which is counterclockwise in Figure 2, and a second direction B2, which is clockwise. The rotation range of the lever portion 71a is restricted to a predetermined range. Figure 2 shows the lever portion 71a in the restricted position, rotated to its limit in the clockwise direction, and Figure 3 shows the lever portion 71a in the released position (fixed position), rotated to its limit in the counterclockwise direction. The restricted position in Figure 2 is also the state in which an image can be formed on the paper by the image forming apparatus. In the following description, the state in which the lever portion 71a in Figure 2 is in the restricted position is also called the restricted state, and the state in which the lever portion 71a in Figure 3 is in the released position is also called the released state. Furthermore, in the following description, the restricted position and released position refer not only to the respective positions of the lever portion 71a, but also to the positions of other members that move in conjunction with the lever portion 71a in the restricted and released states.

[0035] The first portion 20A1 of the inner cover 20A is provided on the downstream side of the lever portion 71a in the counterclockwise direction. By restricting the rotation range of the lever portion 71a to the release position in this way, it is possible to prevent the operator from pinching their fingers between the first portion 20A1 of the inner cover 20A and the lever portion 71a when operating the lever portion 71a.

[0036] When the release lever 71 is in the restricted position shown in Figure 2, the restricting member 72 restricts the removal of the PCDU 10. On the other hand, when the release lever 71 is in the released position shown in Figure 3, the restricting member 72 retracts from the attachment / detachment range of the PCDU 10, allowing the PCDU 10 to be attached to and detached from the image forming apparatus.

[0037] The restricting member 72 contacts the PCDU 10 at a position in the removal direction prior to the position where the PCDU 10 contacts the detection sensor 22, thereby restricting the removal of the PCDU 10. Although Figure 2 shows the case where the restricting member 72 is provided on PCDU 10T and 10C, the restricting member 72 can be provided at any position on the five PCDU 10s mentioned above.

[0038] Next, the mechanism linked to the operation of the release lever 71 will be explained using Figures 4 to 7. Figures 4 and 5 are perspective views of the state with the inner cover 20A removed from Figure 2, and Figures 6 and 7 are front views with the release lever 71 further removed. Also, Figures 4 and 6 show the restricted state, and Figures 5 and 7 show the released state.

[0039] As shown in Figures 4 and 5, the fourth link member 76 moves left and right when the release lever 71 is operated. The fifth link member 77 is connected to the fourth link member 76 by having one end 77b inserted into the hole in the fourth link member 76. A rotating shaft 102 is inserted into the other end of the fifth link member 77, and the fifth link member 77 rotates around the rotating shaft 102. The left and right movement of the fourth link member 76 causes the fifth link member 77 to rotate around the rotating shaft 102. In other words, the direction of movement of the fifth link member 77 is restricted to the rotational direction around the rotating shaft 102, thereby restricting the direction of movement of the fourth link member 76.

[0040] As shown in Figure 6, the first link member 73 is attached to the transfer frame via the lever fixing shaft 71b. The lever fixing shaft 71b is the pivot point of the lever portion 71a (see Figure 5) of the release lever 71, and also serves as the pivot point of the first link member 73. The lever fixing shaft 71b is a rotational shaft that rotates due to the operating force applied by the operator to the lever portion 71a.

[0041] The first link member 73 is connected to the second link member and the third link member, which will be described later, at the connecting portion 73a. One end of a spring 78 is attached to the mounting portion 73b of the first link member 73. The other end of the spring 78 is fixed to the transfer frame.

[0042] Due to the tensile force of the spring 78, the first link member 73 is subjected to a rotational force that causes it to rotate clockwise around the lever fixing shaft 71b in the direction shown in Figure 6. This tensile force causes the lever portion 71a to be positioned in the restricted position shown in Figure 4. On the other hand, when the operator rotates the lever portion 71a of the release lever 71 in the direction from Figure 4 to Figure 5, the first link member 73 rotates counterclockwise against the tensile force of the spring 78 and moves from the position in Figure 6 to the position in Figure 7. Thus, the spring 78 is a biasing member that biases the lever portion 71a in the second direction, the clockwise direction shown in Figure 6.

[0043] The rotational force of the first link member 73 is transmitted to the fourth link member 76 via the second and third link members, which will be described later, causing the fourth link member 76 to move to the left in Figure 7. As a result, the restricting members 72C and 72T attached to the fourth link member 76 move to the released position, which is the position in Figure 7. In other words, as shown in Figures 4 and 6, the restricting members 72C and 72T are provided with elongated holes 72a. Shafts 84 and 85, fixed to the transfer frame, are inserted into the elongated holes 72a, respectively. The posture of the restricting members 72C and 72T is restricted within the range in which shaft 84 or shaft 85 can move relative to each other within the elongated holes 72a. Due to this restriction, the restricting members 72C and 72T move to the restricted position in Figure 6 or the released position in Figure 7 as the fourth link member 76 moves. The hole visible from the front of the restricting member 72 is part of the elongated hole 72a, and in the position shown in Figure 7, the shafts 84 and 85 are located in the hidden portion of the elongated hole 72a (see Figure 17).

[0044] Next, the second link member, the third link member, and the first link member 73 and fourth link member 76 connected to them will be explained using Figures 8 and 9. Figure 8 is a perspective view of Figure 7 with the restricting member 72T removed, and Figure 9 is an exploded perspective view of each link member.

[0045] As shown in Figures 8 and 9, the connecting portion 73a of the first link member 73 is inserted into holes provided at one end 74a of the second link member 74 and one end 75a of the third link member 75, respectively. This connects the first link member 73 to the second link member 74 and the third link member 75. An E-ring is interposed between one end 74a of the second link member 74 and one end 75a of the third link member 75 to reduce the contact area between the two ends.

[0046] The insertion portion 74b, which is the other end of the second link member 74, is inserted into the hole 76a of the fourth link member 76, and the second link member 74 is connected to the fourth link member 76. The insertion portion 75b, which is the other end of the third link member 75, is inserted into the elongated hole 76b of the fourth link member 76, and the insertion portion 75b is provided to be movable relative to the elongated hole 76b. The first link member 73 has an insertion hole 73c into which the lever fixing shaft 71b is inserted. As shown in Figure 8, E-rings are interposed between the first link member 73 and the lever fixing shaft 71b, between the connecting portion 73a and the third link member 75, between the insertion portion 75b and the fourth link member 76, and between the insertion portion 74b and the fourth link member 76.

[0047] The fourth link member 76 is provided with an insertion portion 76c. The insertion portion 76c is the part that is inserted into a hole provided in the restricting member 72 (see Figure 6), and is the part to which the restricting member 72 is attached.

[0048] Next, the rotation of the first link member 73 around the lever fixing shaft 71b transmits rotational force to the fourth link member 76 via the second link member 74 and the third link member 75, causing the fourth link member 76 to move in the left-right direction as shown in Figure 6. This will be explained using Figures 10 to 12. Figure 10 shows the restricted state, Figure 11 shows the transition from the restricted state to the released state, and Figure 12 shows the released state. For convenience, the E-ring interposed between the insertion part 75b and the fourth link member 76 is omitted from Figures 11 and 12.

[0049] In Figures 10 to 12, the lever fixing shaft 71b and the rotation shaft 102 of the fifth link member 77 are rotatably supported by the transfer frame, and their positions do not change.

[0050] As shown in Figure 10 → Figure 11, when the first link member 73 rotates counterclockwise around the lever fixing shaft 71b, the second link member 74 and the third link member 75, which are connected to the first link member 73 at the connecting portion 73a, change their positions in conjunction with the first link member 73. As the second link member 74 and the third link member 75 move, the fourth link member 76, which is connected to the second link member 74 at the insertion portion 74b, moves in the left-right direction in Figure 10, and the fifth link member 77 rotates around the rotation axis 102.

[0051] The insertion portion 75b of the third link member 75 is inserted into the elongated hole 76b of the fourth link member 76, thereby determining the position to which the fourth link member 76 moves. In other words, the lever fixing shaft 71b and the rotation shaft 102 are fixed to the transfer frame, and the positions of the second link member 74 and the fourth link member 76, which are positioned between these two points, are variable. Therefore, simply connecting the second link member 74 and the fourth link member 76 would not allow the position of the fourth link member 76 to be fixed in response to the position change of the first link member 73 due to the rotation of the first link member 73. However, by restricting the range of movement of the insertion portion 75b, which is the other end of the third link member 75, to the elongated hole 76b of the fourth link member 76, the relative position of the third link member 75 and the fourth link member 76 is restricted. This allows the positions of the first link member 73 and the fourth link member 76 to correspond one-to-one, and the fourth link member 76 can be moved to a predetermined position in response to the rotation of the first link member 73. This allows the restricting member 72 (see Figure 7), attached to the insertion portion 76c of the fourth link member 76, to move between the restricted position shown in Figure 10 and the released position shown in Figure 12. In the restricted position shown in Figure 10, the insertion portion 75b of the third link member 75 is positioned at one end of the elongated hole 76b of the fourth link member 76, restricting the fourth link member 76 from moving further to the left in Figure 10. In the released position shown in Figure 12, the insertion portion 75b is positioned at the other end of the elongated hole 76b, restricting the fourth link member 76 from moving further to the right in Figure 12.

[0052] The first link member 73 rotates counterclockwise and moves to the release position shown in Figure 12 due to the operating force applied by the operator to rotate the lever portion 71a (see Figure 2) of the release lever 71. On the other hand, since a clockwise force is applied to the first link member 73 by the spring 78, if the operating force is released while it is positioned other than the release position, it automatically returns to the restricted position shown in Figure 10.

[0053] On the other hand, when the first link member 73 is positioned in the release position shown in Figure 12, the first link member 73 is fixed in that position. Therefore, even if the operator releases the operating force on the lever portion 71a in the release state, the lever portion 71a and the first link member 73 do not return to the restricted position. The fixing mechanism that fixes the lever portion 71a and the first link member 73 in the release position will be explained using Figures 13 and 14. Figures 13 and 14 are views of the transfer device from the rear side of the image forming apparatus, with Figure 13 showing the restricted state and Figure 14 showing the released state.

[0054] As shown in Figure 13, one end of a spring 79 is connected to a front slider 32, which is a mechanism for moving the primary transfer roller 7T toward and away from it. The other end of the spring 79 is fixed to the transfer frame and biases the front slider 32 to the left in Figure 13. A cam follower 81 is attached to the front slider 32.

[0055] A cam 80 is attached to the lever fixing shaft 71b, which is the rotation axis of the release lever. In the restricted state shown in Figure 13, the cam 80 is not in contact with the cam follower 81. On the other hand, in the released state shown in Figure 14, the lever fixing shaft 71b rotates when the release lever is operated, causing the cam 80 to rotate and come into contact with the cam follower 81. The cam follower 81 provided on the front slider 32 is biased to the left in Figure 14. When the cam follower 81 comes into contact with the cam 80, the position of the cam 80, that is, the rotational phase of the lever fixing shaft 71b, is fixed. As a result, the lever portion 71a of the release lever 71 is fixed in the released position.

[0056] As described above, by configuring the lever portion 71a to automatically return to the restricted position when not in the release position, it is possible to prevent the lever portion 71a from remaining in an intermediate position between the release position and the restricted position. If the operator pulls out the PCDU 10 while the lever portion 71a is held in the aforementioned intermediate position, the PCDU will be pulled out before the detection sensor 22 and other components described later have fully retracted from the PCDU 10, resulting in damage or breakage to the detection sensor and intermediate transfer belt. In this embodiment, such damage or breakage to the detection sensor and intermediate transfer belt can be prevented. The cam 80, cam follower 81, front slider 32, spring 78, etc. constitute a fixing mechanism that fixes the lever portion 71a of the release lever 71 in the release position.

[0057] Next, a mechanism for limiting the rotation range of the release lever 71 to the range from the restricted position in Figure 2 to the released position in Figure 3 will be described. The rotation range of the release lever 71 is limited by the fact that the movement range of the insertion portion 76c is restricted to within the elongated hole 75b, and by the rotation range of the fifth link member 77 shown in Figure 10 is restricted. The restriction of the rotation range of this fifth link member 77 will be explained using Figure 15.

[0058] A cam 82, shown in Figure 15(a), is provided on the rotating shaft 102 shown in Figure 4. This cam 82 rotates around the rotating shaft 102 in the direction of the double arrow in Figure 15(a). The range of rotation of the cam 82 is restricted by contact with one wall surface 83a and the other wall surface 83b of the cam follower 83. In other words, the cam 82 rotates within a range from the position where it has rotated to its limit clockwise, as shown in Figure 15(a), to the position where it has rotated to its limit counterclockwise, as shown in Figure 15(b). This, along with the restriction of the movement range of the insertion part 76c within the elongated hole 75b, limits the rotation range of the release lever 71 to the range shown in Figures 2 to 3.

[0059] Next, the detailed configuration of the regulating member 72 will be explained using Figures 16 to 18. Figure 16 is a front side perspective view of the regulating member 72, Figure 17 is a rear perspective view, and Figure 18 is an exploded perspective view of the regulating member 72.

[0060] The restricting member 72 includes a front cover 721, a rear cover 722, a mounting portion 723, and a fixing screw 724. The front cover 721, rear cover 722, and mounting portion 723 are assembled using the fixing screw 724. The front cover 721 and rear cover 722 are restricting portions that contact the PCDU and restrict the movement of the PCDU in the extraction direction. The mounting portion 723 is an elastically deformable portion and in this embodiment is made of a leaf spring. The mounting portion 723 has an insertion hole 723a into which the insertion portion 76c (see Figure 8) of the fourth link member 76 is inserted.

[0061] As shown in Figure 8, the insertion portion 76c is provided with a retaining pin 76c1 to prevent it from coming out of the insertion hole 723a. The retaining pin 76c1 is a spring pin. As shown in Figure 16, the insertion hole 723a has a shape that corresponds to the insertion portion 76c and the retaining pin 76c1. When inserting the insertion portion 76c into the insertion hole 723a, the insertion portion 76c is inserted so that the retaining pin 76c1 aligns with the position of the insertion hole 723a. Furthermore, within the operating range of the restricting member 72 after insertion, the retaining pin 76c1 is positioned so that it does not align with the position of the insertion hole 723a. With this simple configuration, the insertion portion 76c can be prevented from coming out of the insertion hole 723a. Only one retaining pin 76c1 is provided in the circumferential direction of the insertion portion 76c and is provided so as to protrude only in one direction of the insertion portion 76c. For example, compared to a configuration in which retaining pins 76c1 are provided at two locations in the circumferential direction of the insertion portion 76c, this embodiment allows for a smaller area of ​​the insertion hole 723a and improves the strength of the mounting portion 723.

[0062] The regulating member 72 is attached to the transfer device by the mounting portion 723, which is an elastically deformable portion, thereby preventing damage to link members such as the fourth link member 76. In other words, when the regulating member 72 is positioned in the regulating position as shown in Figure 2, if an operator tries to pull out the PCDU 10 with strong force, the PCDU 10 will collide strongly with the regulating member 72. At this time, the elastic deformation of the mounting portion 723 absorbs the impact caused by the collision between the two, thereby reducing the pressure applied to link members such as the fourth link member 76. The mounting portion 723 may be made of a rubber material or the like. However, considering the sliding properties with the shafts 84 and 85 (see Figure 4), it is preferable to use sheet metal such as the leaf spring in this embodiment, or a plate-shaped member with a thickness of 0.5 mm or less.

[0063] In this embodiment, the detection sensor and other components provided in the transfer device are configured to move away from the PCDU. The detection sensor and other components move away from the PCDU in conjunction with the movement of the lever portion 71a of the release lever 71 from the restricted position to the release position.

[0064] The following explanation will describe the primary transfer roller and detection sensor installed in the transfer device, and then describe the separation mechanism that separates the above-mentioned detection sensor and other components from the PCDU.

[0065] As shown in Figure 19(a), the primary transfer roller 7T forms a special color transfer nip NT between itself and the photoreceptor 3T via the intermediate transfer belt 2. The primary transfer roller 7C forms a cyan transfer nip NC between itself and the photoreceptor 3C via the intermediate transfer belt 2. The primary transfer roller 7M forms a magenta transfer nip NM between itself and the photoreceptor 3M via the intermediate transfer belt 2. The primary transfer roller 7Y forms a yellow transfer nip NY between itself and the photoreceptor 3Y via the intermediate transfer belt 2. The primary transfer roller 7K forms a black transfer nip NK between itself and the photoreceptor 3K via the intermediate transfer belt 2.

[0066] The transfer device 20 includes an upstream primary transfer section 201 located on the upstream side in the direction of travel of the intermediate transfer belt 2, a downstream primary transfer section 203 located on the downstream side, and a central primary transfer unit 202 consisting of a plurality of primary transfer sections located between the upstream primary transfer section 201 and the downstream primary transfer section 203. In this embodiment, the upstream primary transfer section 201 transfers a black toner image using a black transfer nip NK, the central primary transfer unit 202 transfers cyan toner images, magenta toner images, and yellow toner images using cyan transfer nip NC, magenta transfer nip NM, and yellow transfer nip NY, and the downstream primary transfer section 203 transfers a special color toner image using a special color transfer nip NT, all to the intermediate transfer belt 2. In the following description, the upstream or downstream side in the direction of travel of the intermediate transfer belt 2 will also be simply referred to as the upstream side or the downstream side.

[0067] In the direction of travel of the intermediate transfer belt 2, a driven roller 21A acting as a tensioning member and a detection sensor 22 acting as a detection mechanism are provided between the primary transfer roller 7C and the primary transfer roller 7T. The driven roller 21A tensions the intermediate transfer belt 2. The detection sensor 22 detects the scale on the intermediate transfer belt 2 and detects the travel speed of the intermediate transfer belt 2. By controlling the speed of the intermediate transfer belt 2 based on this detection result, misalignment of the toner images of each color transferred to the intermediate transfer belt 2 can be suppressed.

[0068] In Figure 19(a), the primary transfer roller 7K located in the uppermost primary transfer section 201 is the uppermost primary transfer member, the primary transfer rollers 7Y, 7M, and 7C located in the central primary transfer unit 202 are the central primary transfer members, and the primary transfer roller 7T located in the lowermost primary transfer section 203 is the lowermost primary transfer member. The direction of travel of the intermediate transfer belt 2 is indicated by arrow A in Figure 19(a). Furthermore, the primary transfer rollers 7K, 7Y, 7M, and 7C located upstream of the primary transfer roller 7T are also upstream primary transfer members.

[0069] In this embodiment, the special color can be transferred in either the upstream primary transfer unit 201 or the downstream primary transfer unit 203. This makes it possible to transfer the special color toner in the required order.

[0070] In the direction of travel of the intermediate transfer belt 2, a driven roller 21A acting as a second tensioning roller and a detection sensor 22 acting as a detection mechanism are provided between the primary transfer roller 7C and the primary transfer roller 7T. The driven roller 21A tensions the intermediate transfer belt 2. The detection sensor 22 detects the scale on the intermediate transfer belt 2 and detects the travel speed of the intermediate transfer belt 2. By controlling the speed of the intermediate transfer belt 2 based on this detection result, misalignment of the toner images of each color transferred to the intermediate transfer belt 2 can be suppressed.

[0071] In the transfer apparatus 20 of this embodiment, each primary transfer roller 7 contacts or separates from the photoreceptor 3 via the intermediate transfer belt 2, according to the mode during image formation. For example, as shown in Figure 19(b), the primary transfer roller 7T of the downstream primary transfer section 203 can be separated from the photoreceptor 3T, while the other primary transfer rollers 7 can be brought into contact with each photoreceptor 3 via the intermediate transfer belt 2. Figure 19(b) is an example, and the contact and separation states of each primary transfer roller 7 of the upstream primary transfer section 201, the central primary transfer unit 202, and the downstream primary transfer section 203 can be switched.

[0072] In conjunction with the contact and separation movement of the downstream primary transfer roller 7T with respect to the photoreceptor 3T, the driven rollers 21A and 33A, which act as tensioning members for tensioning the intermediate transfer belt 2, and the detection sensor 22 also move in the direction of contact and separation from the photoreceptor 3, which is the vertical direction in Figure 19. The first contact and separation mechanism for moving these members will be explained below using Figures 13 and 20 to 22. Figure 13 is a diagram of the aforementioned restricted state, but it is also a diagram of the slider 32 in the "contact" state. In the following explanation, the case where a special color toner image is transferred in the downstream primary transfer section 203 is shown, but a black toner image may also be transferred.

[0073] As shown in Figure 13, a primary transfer roller 7T is provided at one end of a rotating member 34. The rotating member 34 is rotatable around a pivot point 34a. The rotating member 34 has a hole 34b at the end opposite to the side on which the primary transfer roller 7T is provided. A pin 32b provided on the front slider 32 is inserted into the hole 34b. A spring 35 is fixed to the housing of the image forming apparatus and biases the rotating member 34 to rotate clockwise around the pivot point 34a as shown in Figure 13. Due to the biasing force of this spring 35, the primary transfer roller 7T is in contact with the intermediate transfer belt 2. A driven roller 33A, which is one of the tensioning members that tensions the intermediate transfer belt 2, is provided at one end of a rotating member 33. The rotating member 33 is rotatable around a pivot point 33a. The rotating member 33 has a hole 33b at the end opposite to the side on which the driven roller 33A is provided. An insertion portion 32a, provided on the front slider 32, is inserted into the hole 33b. The insertion portion 32a is constructed by press-fitting a ball bearing into a shaft fixed to the front slider 32. Furthermore, a driven roller 21A is provided on one end of the rotating member 21. The rotating member 21 is rotatable around a pivot point 21a. The rotating member 21 is subjected to a force by the spring 39 that causes it to rotate clockwise around the pivot point 21a.

[0074] The first contact / disengagement mechanism 91 is provided with a cam member 31 that transmits the driving force of the motor. As shown in Figure 20, the cam member 31 has a first cam 31A and a second cam 31B, and is rotatably mounted around the rotation shaft 31a. The second cam 31B is a ball bearing with an outer ring and is an eccentric cam with respect to the rotation shaft 31a.

[0075] The first cam 31A has small diameter, medium diameter, and large diameter sections, each with a diameter of 120 degrees. As shown in Figure 21, the first cam 31A contacts the cam follower 36, which is made of ball bearings. By rotating the first cam 31A, the surface on which the first cam 31A contacts the cam follower 36 is changed, allowing the front slider 32 to be moved in the left-right direction in Figure 13.

[0076] Figure 22 shows the "separated" state in which the primary transfer roller 7T is separated from the photoreceptor. The rotation of the first cam 31A moves the front slider 32 to the right of the position shown in Figure 13, causing the primary transfer roller 7T to move away from the photoreceptor in a "separated" state. In other words, as the front slider 32 moves to the right from Figure 13 to Figure 22, the insertion portion 32a, pin 32b, and pin 32c (see Figure 24) provided on the front slider 32 press against the rotating members 33, 34, and 21, respectively, causing the rotating members 33, 34, and 21 to rotate counterclockwise. As a result, the driven roller 33A, the primary transfer roller 7T, and the driven roller 21A move downward in Figure 22, away from the photoreceptor. The movement of the driven rollers 33A and 21A causes the tension position of the intermediate transfer belt 2 stretched over these rollers to move downward in Figure 22.

[0077] Furthermore, as shown from Figure 13 to Figure 22, the front slider 32 moves, causing the detection sensor 22 to move downwards in Figure 22. This allows the detection sensor 22 to be moved in accordance with the tension position of the intermediate transfer belt 2. The mechanism for moving this detection sensor 22 will be described below.

[0078] As shown in Figures 21 and 23, the first arm 37 grips the second cam 31B at two points, gripping portions 37c1 and 37c2. The rotation of the second cam 31B causes the first arm 37 to rotate around the pivot point 37a. As the front slider 32 moves from Figure 13 to Figure 22, the first arm 37 rotates clockwise around the pivot point 37a as shown in Figure 23.

[0079] As shown in Figure 21, a thrust stopper member 60, which acts as both a restricting member and a retaining member, is attached to the first arm 37. The thrust stopper member 60 restricts the relative direction of movement of the first arm 37 with respect to the second cam 31B by restricting the position of the outer circumferential surface of the second cam 31B with its restricting portion 60b. In other words, it can restrict the first arm 37 from moving in a direction other than along the outer circumferential surface of the second cam 31B, for example, in the sliding direction relative to the second cam 31B.

[0080] Figure 24 is a front perspective view of the area around the first arm 37 and the second arm 38. Figure 25 is a rear perspective view of the first arm 37 and the second arm 38.

[0081] As shown in Figure 24, the second arm 38, as a second link member, has other elongated holes 38a and 38b at both ends. One end 37b of the first arm 37 is inserted into the other elongated hole 38a. As shown in Figure 25, the one end 37b of the first arm 37 has a bearing 40. The bearing 40 is provided so as to be able to move relative to the other elongated hole 38a. The bearing 40 is the other insertion part into the other elongated hole 38a.

[0082] As shown in Figure 24, a bearing 41 is inserted into the elongated hole 38b. The bearing 41 is fixed to the first sensor bracket 43, which acts as a retaining member, by a stepped screw 42. The bearing 41 is provided to be movable within the elongated hole 38b. The bearing 41 is the insertion part for the elongated hole 38b.

[0083] The rotation of the cam member 31 moves the front slider 32 to the right of Figure 13 from the state shown in Figure 13, placing the downstream primary transfer section 203 in a "separated" state. This causes the second cam 31B to rotate, and the first arm 37 rotates clockwise around the pivot point 37a. As a result, one end 37b of the first arm 37 moves downward in Figure 13. As a result, as shown in Figure 22, one end 37b moves to one end of the other elongated hole 38a and contacts the wall surface forming the other elongated hole 38a, pulling the second arm 38 downward in Figure 22. As a result, the bearing 41 moves relative to one end of the elongated hole 38b and contacts the wall surface forming the elongated hole 38b. Then, the second arm 38 pulls the first sensor bracket 43 downward in Figure 22.

[0084] Figure 26 shows the configuration around the first sensor bracket 43 and the detection sensor 22, and is a diagram showing the state with the rotating member 21 removed from Figure 13 and other figures. For convenience, the detection sensor 22 and the second sensor bracket 44 are shown in a simplified manner in Figure 26.

[0085] As shown in Figure 26, the first sensor bracket 43 is rotatably mounted around a pivot point 43a. The first sensor bracket 43 is subjected to a force by a spring 45 fixed to the housing of the image forming apparatus, which causes it to rotate counterclockwise around the pivot point 43a as shown in Figure 26. A regulating bracket 63 is also fixed to the first sensor bracket 43. The pin 32d of the front slider 32 is inserted into the hole 63a of the regulating bracket 63. In the "contact" state shown in Figure 13, the pin 32d contacts the wall surface forming the hole 63a, causing the front slider 32 to apply a force to the first sensor bracket 43 that causes it to rotate clockwise around the pivot point 43a as shown in Figure 26.

[0086] The second sensor bracket 44 is fixed to the first sensor bracket 43 via a stud 43b provided on the first sensor bracket 43. The second sensor bracket 44 holds the detection sensor 22. The second sensor bracket 44 has a hook 44a to which one end of a spring 62 (see Figure 13) is attached, a first contact portion 44b, and a second contact portion 44c.

[0087] In the "contact" state shown in Figure 13, the second sensor bracket 44 is biased by the spring 62 and moves in a direction that rotates clockwise around the pivot point 43a, and is positioned so that the first contact portion 44b contacts the stud 64 provided on the housing of the image forming apparatus.

[0088] Furthermore, in the "separated" state shown in Figure 22, as the pin 32d moves to the right, the force that the pin 32d exerts on the restricting bracket 63 to the left in Figure 26 is released, as shown in Figure 26. Simultaneously, as described above, the second arm 38 pulls the first sensor bracket 43 towards the lower left of Figure 26, causing the first sensor bracket 43 to rotate clockwise around the pivot point 43a in Figure 26. As a result, the second sensor bracket 44, which is fixed to the first sensor bracket 43 via the stud 43b, moves upward in Figure 26, and the detection sensor 22 also moves upward in Figure 26. At this time, as shown in Figure 27, the second sensor bracket 44 is positioned so that its second contact portion 44c contacts the positioning portion 21b of the rotating member 21. In other words, the upward movement of the second sensor bracket 44 and the detection sensor 22 in Figure 26 is restricted, and the detection sensor 22 is positioned.

[0089] As described above, in this embodiment, when the front slider 32 moves from Figure 13 to the right in Figure 22, the primary transfer roller 7T, driven roller 21A, driven roller 33A, and detection sensor 22 each move away from the photoreceptor. In the above description, the case in which the front slider 32 moves to the right in Figure 22 due to the driving force of the motor was shown, but the front slider 32 can also be moved to the right by the operating force on the lever portion 71a. The movement of the front slider 32 by operating the lever portion 71a will be described below.

[0090] As shown in Figures 2 and 3 above, moving the lever portion 71a from the restricted position to the released position causes the lever fixing shaft 71b and cam 80, which are the pivot points of the lever portion 71a, to rotate as shown in Figures 13 and 14. During this process, the cam 80 comes into contact with the cam follower 81 attached to the front slider 32, and the cam follower 81 moves the front slider 32 to the right as shown in Figures 13 and 14. This allows the primary transfer roller 7T, driven roller 21A, driven roller 33A, and detection sensor 22 to move away from the photoreceptor, similar to when the cam member 31 is rotated by the motor and moved from the "contact" state to the "separated" state as shown in Figures 13 and 22.

[0091] As described above, the front slider 32, first arm 37, second arm 38, first sensor bracket 43, second sensor bracket 44, regulating bracket 63, spring 45, spring 62, etc. constitute a contact / separation mechanism that moves the detection sensor 22 toward and away from the PCDU 10 (or photoreceptor).

[0092] As described above, according to this embodiment, by operating the lever portion 71a, the restricting member 72 that restricts the movement of the PCDU 10 in the removal direction can be retracted from the PCDU 10, as shown in Figure 2 → Figure 3, thereby releasing the restriction on the removal of the PCDU 10 by the restricting member 72. In addition, the detection sensor 22 that interferes with the PCDU 10 during the removal operation of the PCDU 10 can be moved in the direction of retraction from the PCDU 10. In other words, by operating the lever portion 71a alone, the PCDU 10 can be made removable from the image forming apparatus, and interference with other components due to the removal of the PCDU 10 can also be prevented.Therefore, the number of steps during the removal operation of the PCDU 10 can be reduced, and the convenience of operations such as the removal of the PCDU 10 and maintenance of the image forming apparatus can be improved. Furthermore, problems such as forgetting to retract the detection sensor 22 during the removal operation of the PCDU 10 and damaging the detection sensor 22 or the PCDU 10 can be prevented.

[0093] Furthermore, as in this embodiment, not only the detection sensor 22, but also tensioning members that tension the intermediate transfer belt 2, such as the primary transfer roller 7T and the driven roller 21A, can be included in the contact / separation section that moves in a direction away from the PCDU 10 (or photoreceptor) by operating the lever section 71a. This allows these members to be retracted even if the intermediate transfer belt or primary transfer roller interferes with the PCDU 10 when the PCDU 10 is removed from the image forming apparatus. However, it is not necessary to retract all of these members by the operating force of the lever section 71a. Moreover, the members to be retracted from the PCDU 10 are not limited to these, and members provided in the transfer apparatus 20 can be configured to move away from the PCDU 10 as appropriate.

[0094] Furthermore, although the above description shows a configuration in which the primary transfer roller 7T of the downstream primary transfer section moves away from the photoreceptor in conjunction with the detection sensor 22 and the regulating member 72, the present invention is not limited to this, and any other primary transfer roller may move away from the photoreceptor. Also, the placement of the detection sensor 22 is not limited to the position between the downstream primary transfer section and the central primary transfer unit as in the present invention.

[0095] Next, the second contact / separation mechanism 92, which acts as a second moving mechanism to bring the primary transfer rollers 7C, 7M, and 7Y provided in the central primary transfer unit 202 into contact with and separate from the intermediate transfer belt 2, and the third contact / separation mechanism 93, which acts as a third moving mechanism to bring the primary transfer roller 7K provided in the uppermost primary transfer section 201 into contact with and separate from the intermediate transfer belt 2, will be explained with reference to Figure 28.

[0096] As shown in Figure 28, the second contact / disconnection mechanism 92 includes rotating members 46-48, a cam 51, and a cam follower 52. The third contact / disconnection mechanism 93 includes a rotating member 49, a cam 53, and a cam follower 54. The second contact / disconnection mechanism 92 is equipped with a motor as a drive source for rotating the cam 51, and the third contact / disconnection mechanism 93 is equipped with a motor as a drive source for rotating the cam 53.

[0097] Rotating members 46, 47, 48, and 49 are rotatably mounted around pivot points 46a, 47a, 48a, and 49a. A primary transfer roller 7C is provided at one end of rotating member 46. A primary transfer roller 7M is provided at one end of rotating member 47. A primary transfer roller 7Y is provided at one end of rotating member 48. A primary transfer roller 7K is provided at one end of rotating member 49. Each of the rotating members 46 to 49 is biased by a spring to rotate in the clockwise direction shown in Figure 28, and each primary transfer roller 7 is brought into contact with the photoreceptor via the intermediate transfer belt 2.

[0098] The rotation of the cam 51 causes the cam follower 52 to rotate, moving the front slider 50 of the uppermost primary transfer section 201 to the right in Figure 28. This presses the ends of the rotating members 46-48 opposite to the side on which the primary transfer rollers 7 are installed, causing each of the rotating members 46-48 to rotate counterclockwise in Figure 28 against the biasing force of the spring. This causes each of the primary transfer rollers 7C, 7M, and 7Y to move away from each of the photoreceptors. The rotation of the cam 53 also causes the cam follower 54 to rotate, pressing the end of the rotating member 49 opposite to the side on which the primary transfer roller 7K is installed. This causes the rotating member 49 to rotate counterclockwise in Figure 28 against the biasing force of the spring, causing the primary transfer roller 7K to move away from the photoreceptor. As described above, the primary transfer roller 7K of the uppermost primary transfer section 201 and the primary transfer rollers 7C, 7M, and 7Y of the central primary transfer unit 202 independently perform contact and separation operations with respect to each photoreceptor.

[0099] Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the present invention.

[0100] In the above description, the operating member is shown as being provided in the transfer device, but it may also be provided at an appropriate location within the image forming apparatus, such as in the housing of the image forming apparatus.

[0101] In the above description, a secondary transfer apparatus having an intermediate transfer belt was shown as an example of the transfer apparatus according to the present invention, but the present invention is not limited thereto. For example, the transfer apparatus may also have a transport belt that transports the recording medium and forms a transfer nip with the photoreceptor.

[0102] Recording media include plain paper (P), as well as cardboard, postcards, envelopes, thin paper, coated paper (such as coated paper and art paper), tracing paper, OHP sheets, plastic film, prepreg, copper foil, and the like.

[0103] Examples of the present invention are as follows: <1> A connecting / separating part is provided to be able to move toward and away from the latent image carrier unit, A contact / separation mechanism that brings the contact / separation portion into contact with and separates from the latent image carrier unit, Regulating member and, A transfer apparatus comprising an operating member, The restricting member restricts the removal of the latent image carrier unit from the image forming apparatus. The transfer apparatus is characterized in that, by operating the operating member, the connecting / separating mechanism separates the connecting / separating portion from the latent image carrier unit, and the restriction by the restricting member on the removal of the latent image carrier unit from the image forming apparatus is released. <2> The operating member has an operating section that can be operated in a first direction and a second direction which are opposite to each other. The operating section has a fixing mechanism for fixing it in a predetermined fixed position in the first direction, and a biasing member for biasing the operating section in the second direction. <1> This is the transfer device described. <3> A rotating shaft that rotates due to the operating force of the aforementioned operating member, It has a link member that moves by receiving the rotational force of the aforementioned rotating shaft, The restricting member is attached to the link member. <1> or <2> This is the transfer device described. <4> The transfer device according to <3>, wherein the regulating member has an elastically deformable portion attached to the link member. <5> The transfer device according to <4>, wherein the elastically deformable portion is a leaf spring. <6> The transfer device according to <4>, wherein the elastically deformable portion is a plate-shaped member having a thickness of 0.5 mm or less. <7> the elastically deformable portion has an insertion hole, the link member has an insertion portion inserted into the insertion hole, The transfer device according to any one of <4> to <6>, wherein the insertion portion has a retaining pin that prevents falling off from the insertion hole. <8> The transfer device according to <7>, wherein the retaining pin extends in one circumferential direction of the insertion portion. <9> The transfer device according to any one of <3> to <8> according to <2> or <2>, comprising a transfer frame having a first portion, the first portion is provided on a downstream side of the operation portion in the first direction, the transfer device wherein the fixed position is provided on an upstream side of the operation portion in the first direction relative to the first portion. <10> the latent image carrier unit, An image forming apparatus comprising the transfer device according to any one of <1> to <9>. <11> a latent image carrier unit having at least a latent image carrier, a transfer device comprising: a contacting / separating portion provided so as to be capable of coming into contact with and separating from the latent image carrier unit; a contacting / separating mechanism for bringing the contacting / separating portion into contact with and separating from the latent image carrier unit; and a regulating member, An image forming apparatus comprising an operation member, the latent image carrier unit is provided detachably with respect to an image forming apparatus main body, the regulating member regulates removal of the latent image carrier unit from the image forming apparatus main body, The image forming apparatus is characterized in that, by operating the operating member, the connecting / separating mechanism separates the connecting / separating portion from the latent image carrier unit, and the restriction by the restricting member on removing the latent image carrier unit from the image forming apparatus body is released. [Explanation of Symbols]

[0104] 1. Image forming apparatus 2. Intermediate transfer belt (belt member or intermediate transfer body) 7. Primary transfer roller (transfer member) 10 PCDU (Latent Image Carrier Unit) 20 Transfer device 20A Inner Cover (Transfer Frame) 20A1 Part 1 22 Detection sensor (contact / separation part) 71 Release lever (operating component) 71a Lever section (operating section) 71b Lever fixing axis (rotation axis) 72 Regulating members 723 Mounting part (elastically deformable part) 723a Insertion hole 73 First link member 74 Second link member 75 Third link member 76. Fourth link member (link member) 76c Insertion part 76c1 Retaining pin 77 Fifth link member 78. Spring (biasing member) B1 1st direction B2 2nd direction [Prior art documents] [Patent Documents]

[0105] [Patent Document 1] Japanese Patent Publication No. 2018-13503

Claims

1. A transfer belt and A contact / separation portion is provided on the inside of the transfer belt and is provided to be able to move toward and away from the latent image carrier unit, A contact / separation mechanism that brings the contact / separation portion into contact with and separates from the latent image carrier unit, Regulating member and, A transfer apparatus comprising an operating member, The restricting member restricts the removal of the latent image carrier unit from the image forming apparatus. A transfer apparatus characterized in that, by operating the operating member, the connecting / separating mechanism separates the connecting / separating portion from the latent image carrier unit, and the restriction by the restricting member on the removal of the latent image carrier unit from the image forming apparatus is released.

2. A connecting / separating part provided to be able to connect to and separate from the latent image carrier unit, A contact / separation mechanism that brings the contact / separation portion into contact with and separates from the latent image carrier unit, Regulating member and, A transfer apparatus comprising an operating member, The restricting member restricts the removal of the latent image carrier unit from the image forming apparatus. By operating the operating member, the connecting / separating mechanism separates the connecting / separating portion from the latent image carrier unit, and the restriction by the restricting member on removing the latent image carrier unit from the image forming apparatus is released. The operating member has an operating section that can be operated in a first direction and a second direction which are opposite to each other. A transfer apparatus characterized by having a fixing mechanism for fixing the operating section at a predetermined fixed position in the first direction, and a biasing member for biasing the operating section in the second direction.

3. A contact / separation portion provided to be able to move toward and away from the latent image carrier unit, A contact / separation mechanism that brings the contact / separation portion into contact with and separates from the latent image carrier unit, Regulating member and, A transfer apparatus comprising an operating member, The restricting member restricts the removal of the latent image carrier unit from the image forming apparatus. By operating the operating member, the connecting / separating mechanism separates the connecting / separating portion from the latent image carrier unit, and the restriction by the restricting member on removing the latent image carrier unit from the image forming apparatus is released. A rotating shaft that rotates due to the operating force of the aforementioned operating member, It has a link member that moves by receiving the rotational force of the aforementioned rotating shaft, The transfer device is characterized in that the regulating member is attached to the link member.

4. The transfer apparatus according to claim 3, wherein the restricting member has an elastically deformable portion attached to the link member.

5. The transfer apparatus according to claim 4, wherein the elastically deformable part is a leaf spring.

6. The transfer apparatus according to claim 4, wherein the elastically deformable portion is a plate-like member with a thickness of 0.5 mm or less.

7. The aforementioned elastically deformable portion has an insertion hole, The link member has an insertion portion that is inserted into the insertion hole, The transfer apparatus according to claim 4, wherein the insertion portion has a retaining pin to prevent it from falling out of the insertion hole.

8. The transfer apparatus according to claim 7, wherein the retaining pin extends in one direction in the circumferential direction of the insertion portion.

9. A transfer apparatus according to claim 2, comprising a transfer frame having a first part, The first portion is provided on the downstream side of the operating section in the first direction, The fixed position is a transfer device provided upstream of the first portion in the first direction of the operating section.

10. The latent image carrier unit having at least a latent image carrier, An image forming apparatus comprising a transfer apparatus according to any one of claims 1 to 9.

11. A latent image carrier unit having at least a latent image carrier, A transfer apparatus comprising: a transfer belt; a contact / separation portion provided inside the transfer belt and capable of moving toward and away from the latent image carrier unit; a contact / separation mechanism for moving the contact / separation portion toward and away from the latent image carrier unit; and a regulating member. An image forming apparatus comprising an operating member, The latent image carrier unit is detachably attached to the main body of the image forming apparatus. The restricting member restricts the removal of the latent image carrier unit from the image forming apparatus body. An image forming apparatus characterized in that, by operating the operating member, the connecting / separating mechanism separates the connecting / separating portion from the latent image carrier unit, and the restriction by the restricting member on removing the latent image carrier unit from the image forming apparatus body is released.

12. The transfer apparatus according to any one of claims 1 to 9, wherein the contact / separation section includes a primary transfer roller.

13. The transfer apparatus according to any one of claims 1 to 9, wherein the contact / separation portion includes a sensor.

14. The image forming apparatus according to claim 11, wherein the contact / separation portion includes a primary transfer roller.

15. The image forming apparatus according to claim 11, wherein the contact / separation portion includes a sensor.

Images