Image forming device

Abstract

To provide an image forming apparatus in which when an exposure unit already connected with one end of a bundle wire is inserted into and mounted in a housing of the image forming apparatus, the bundle wire before being connected to a control board hardly interferes with the housing.SOLUTION: An FFC guide 83 holding a bundle wire 58 has a first locking pawl 87, and the first locking pawl 87 has a first locking part 89 to be locked to a connection stay, and a second locking part 88 to be locked to a cartridge tray 30. The FFC guide 83 can be locked to the cartridge tray 30 before being mounted in a housing A, and after the cartridge tray 30 is mounted in the housing, is removed from the cartridge tray 30 and locked to the connection stay. In this way, the FFC guide 83 can be locked to a temporary position different from a regular position in the cartridge tray 30, and during insertion of the cartridge tray 30 into the housing, the bundle wire 58 before being connected to a control board hardly interferes with the housing.SELECTED DRAWING: Figure 17

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus using electrophotographic technology, such as a printer, a copying machine, a facsimile machine, or a multifunction machine. [Background technology]

[0002] As an exposure unit that forms an electrostatic latent image by irradiating the surface of a photosensitive member with light in an image forming apparatus, for example, an LED array type exposure unit in which multiple light-emitting elements are arranged along the rotation axis direction of the photosensitive member has been proposed (Patent Document 1). In this exposure unit, the light-emitting elements are turned on and off in accordance with a light-emitting control signal from a control board that is electrically connected by a cable. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-57340 Summary of the Invention [Problem to be solved by the invention]

[0004] One end of the cable is already connected to the exposure unit. The exposure unit is held by a holder with the other end of the cable not attached to the control board, and the holder is inserted into the housing of the image forming apparatus to install it. After installing the exposure unit, the other end of the cable is connected to the control board disposed in the housing via a connector. However, in the past, when inserting the exposure unit into the housing, the cable before being connected to the control board would interfere with the housing, potentially damaging or breaking the cable.

[0005] The present invention has been made in consideration of the above-mentioned problems, and aims to provide an image forming apparatus in which, when an exposure unit with one end of a cable already connected is inserted into the housing of the image forming apparatus and mounted, the cable before being connected to the control board is less likely to interfere with the housing. [Means for solving the problem]

[0006] An image forming apparatus according to one embodiment of the present invention is an image forming apparatus that forms a toner image on a recording material, and is characterized in that it comprises: a housing; a photosensitive body; an exposure unit having a plurality of light-emitting elements for irradiating light onto the photosensitive body to expose it; a holder that holds the exposure unit and is insertable into the housing; a control board that is provided in the housing and controls the exposure unit; a cable that has one end connected to the exposure unit and the other end freely connectable to the control board, electrically connecting the exposure unit and the control board; and a cable holding member that holds the cable; the cable holding member has a protruding portion that protrudes from a second surface opposite to the first surface that holds the cable, and that engages with a first engaging portion of the housing with a first engaging portion, and the protruding portion has a second engaging portion that is at a position at a height from the second surface different from that of the first engaging portion, for engaging with a second engaging portion of the holder. [Effects of the Invention]

[0007] According to the present invention, when a holder holding an exposure unit with one end of a cable already connected is inserted into the housing of an image forming device and attached, the cable before being connected to the control board is less likely to interfere with the housing. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is an external perspective view showing an image forming apparatus according to an embodiment of the present invention; [Figure 2] FIG. 1 is a schematic diagram illustrating a configuration of an image forming apparatus. [Figure 3] FIG. 2 is a schematic diagram showing the image forming apparatus in a state where the developing unit and the exposure unit are retracted. [Figure 4] FIG. [Figure 5] FIG. [Figure 6] (a) A perspective view showing a mounting substrate, (b) a schematic diagram showing a light-emitting element on the mounting substrate, (c) an enlarged view of the light-emitting element on the mounting substrate, (d) a schematic diagram showing a lens assembly, and (e) a perspective view showing the lens assembly. [Figure 7] FIG. [Figure 8] FIG. 2 is a perspective view showing a state in which a mounting board is attached to a housing in the exposure unit. [Figure 9] FIG. 9 is an enlarged view showing a part of FIG. 8; [Figure 10] 9 is a perspective view showing a state in which the lens assembly is further attached to the housing from the state shown in FIG. 8. [Figure 11] FIG. 2 is a perspective view showing two sides of the exposure unit. [Figure 12] FIG. 4 is an enlarged view showing a part of two surfaces of the exposure unit. [Figure 13] FIG. 4 is a diagram for explaining the electrical connection between a control board and an exposure unit. [Figure 14] FIG. 2 is a perspective view showing a state in which a cartridge tray is attached to a housing. [Figure 15] FIG. [Figure 16] 1A and 1B are a left side view and a cross-sectional view of the FFC guide in the state where the FFC guide is engaged with the connecting stay, respectively; [Figure 17] 10A and 10B are a top view and a cross-sectional view taken along the line EE, respectively, showing a state in which the FFC guide is engaged with the cartridge tray. [Figure 18] FIG. 10 is a front view showing a comparative example in which, when the cartridge tray is inserted into the housing, the bundled wires before being connected to the control board interfere with the housing. DETAILED DESCRIPTION OF THE INVENTION

[0009] [Image forming equipment] The present embodiment will be described below. First, an overview of the image forming apparatus of the present embodiment will be described with reference to FIGS. 1 to 3. As shown in FIG. 1, the image forming apparatus 100 of the present embodiment is a so-called internal discharge type image forming apparatus. That is, the image forming apparatus 100 includes a housing 100A and a document reading device 41 that reads an image of a document, and an output tray 21 that stacks the recording material S discharged from the housing 100A is formed between the housing 100A and the document reading device 41. The image forming apparatus 100 forms a toner image on the recording material S in response to an image signal from the document reading device 41 or an external device (not shown) such as a personal computer.

[0010] The housing 100A is provided with an operation unit 46 on the front side, which has a display unit capable of displaying various information and keys for inputting various information in response to user operations. In this specification, the side on which a user stands when operating the operation unit 46 to operate the image forming apparatus 100 is referred to as the "front (front)," and the opposite side is referred to as the "rear (back)." Furthermore, the left side when viewing the image forming apparatus 100 from the front is referred to as the "left," and the right side when viewing the image forming apparatus 100 from the front is referred to as the "right."

[0011] Housing 100A is made up of multiple metal plates, such as a front plate provided on the front side of image forming apparatus 100, a rear plate provided on the rear side and supporting each unit together with the front plate, front columns supporting the front plate, rear columns supporting the rear plate, and stays connecting the front and rear columns, and is covered with an exterior cover that constitutes the exterior of image forming apparatus 100. As exterior covers, front cover 101, multiple cassette covers 103, and upper front cover 104 are arranged on the front side. In addition, side covers 105 and 106 are arranged on the left and right side sides, and a rear cover 325 is arranged on the rear side.

[0012] 2 and 3 includes four image forming units 1Y, 1M, 1C, and 1K that form toner images of four colors: yellow (Y), magenta (M), cyan (C), and black (K). Note that the configurations of the image forming units 1Y, 1M, 1C, and 1K that form toner images of each color are almost the same, so in FIGS. 2 and 3, the magenta image forming unit 1M is given a symbol as a representative, and the description will be given using the image forming unit 1M as an example.

[0013] The image forming section 1M is equipped with two units: a drum unit 23 (also called a drum cartridge) and a developing unit 24 (also called a developing cartridge) (see FIG. 3). The drum unit 23 and developing unit 24 are supported by a cartridge tray 30. The cartridge tray 30 is formed with a concave cross-section, with an open top end face on the drum unit side and an open top end face on the developing unit side. The drum unit and developing unit are each detachably mounted on the cartridge tray 30 from the front side of the housing 100A so as to be guided in the front-rear direction. The cartridge tray 30 is made of an easily processable resin so that units with complex shapes, such as the drum unit 23 and developing unit 24, can be easily attached.

[0014] The drum unit 23 has a photosensitive drum 2 as a photosensitive member, a charging roller 3 that charges the photosensitive drum 2, and a drum cleaner (not shown). The development unit 24 is disposed in a developer container that contains a developer including toner, and has a development sleeve 5 that supplies toner to the photosensitive drum 2 to form a toner image, and a conveying screw 7 that conveys the toner while stirring it and supplies it to the development sleeve 5. Between the drum unit and the development unit in the rotation direction of the photosensitive drum 2, an exposure unit 4 is disposed that exposes the surface of the photosensitive drum 2 to light to form an electrostatic latent image. The exposure unit 4 is disposed between the drum unit 23 and the development unit 24 and is held by a cartridge tray 30.

[0015] An intermediate transfer belt unit 8 is disposed above the image forming stations 1Y to 1K. The intermediate transfer belt unit 8 has four primary transfer rollers 6 arranged to face the photosensitive drums 2 of each color, and one endless intermediate transfer belt 9. Above this intermediate transfer belt unit 8, toner bottles 22Y to 22K containing replenishment toner to be supplied to the developing units are detachably mounted on a toner supply mechanism (not shown). The toner supply mechanism replenishes the appropriate amount of toner from the toner bottles 22Y to 22K to the corresponding developing units of the image forming stations 1Y to 1K at the appropriate time. Below the image forming stations 1Y to 1K, sheet cassettes 12A and 12B containing recording material S are disposed.

[0016] <Image formation process> Next, the image forming process on the recording material S in the image forming apparatus 100 will be described. In each of the image forming units 1Y to 1K, the surface of the photosensitive drum 2, which is driven to rotate by a motor (not shown), is uniformly charged by a charging roller 3 pressed against the photosensitive drum 2. Thereafter, an exposure unit 4, which is driven based on a signal of image information, irradiates the surface of the photosensitive drum 2 with light, and an electrostatic latent image is formed on the surface of the photosensitive drum 2. The electrostatic latent image formed on the photosensitive drum 1 is developed into a toner image by a developing unit. The developing unit develops the electrostatic latent image with toner contained in a developer, and forms a toner image on the photosensitive drum 1.

[0017] In the developing unit, a high voltage is applied to the developing sleeve 5, and the toner is stirred by the conveying screw 7, causing the charged toner to be uniformly coated on the surface of the developing sleeve 5. The conveying screw 7 rotates at a relatively high speed compared to the rotational speed of the developing sleeve 5 and the photosensitive drum 2, thereby coating the toner evenly and uniformly on the surface of the developing sleeve 5.

[0018] The toner image formed on the photosensitive drum 2 is primarily transferred from the photosensitive drum 2 to the intermediate transfer belt 9 by applying a primary transfer voltage to a primary transfer roller 6 disposed opposite the image forming units 1Y to 1K with the intermediate transfer belt 9 interposed therebetween. A drum cleaner unit (not shown) collects residual toner remaining on the photosensitive drum 2 after the primary transfer.

[0019] Within the housing 100A of the image forming apparatus 100, a sheet transport path for transporting the recording material S from bottom to top is provided on the right side. Arranged on this sheet transport path from bottom to top are a supply roller pair 13, a registration roller pair 15, a secondary transfer outer roller 16, a fixing unit 19, and a discharge roller pair 20. The secondary transfer outer roller 16 abuts against the secondary transfer inner roller 10, which is arranged inside the intermediate transfer belt 9, with a predetermined pressure across the intermediate transfer belt 9, thereby forming a secondary transfer nip portion 17.

[0020] The recording materials S stored in sheet cassettes 12A and 12B are supplied one by one from either sheet cassette 12A or 12B to a sheet conveying path by driving a supply roller pair 13 at a predetermined control timing. The recording materials S supplied by the supply roller pair 13 are conveyed to a registration roller pair 15 arranged midway along the conveying path. The registration roller pair 15 then performs skew correction and timing correction on the recording material S, and the recording material S is sent to a secondary transfer nip portion 17. The secondary transfer nip portion 17 is formed by a secondary transfer inner roller 10 and a secondary transfer outer roller 16 that face each other across the intermediate transfer belt 9, and is a nip portion where a toner image is transferred from the intermediate transfer belt 9 to the recording material S by applying a predetermined pressure and secondary transfer voltage.

[0021] The image forming processes for each color, which are processed in parallel by the image forming units 1Y to 1K for each color described above, are performed in a timed manner to sequentially superimpose the image onto the toner image of the color that was primarily transferred onto the intermediate transfer belt 9 upstream in the movement direction. As a result, a full-color toner image is formed on the intermediate transfer belt 9 and is transported to the secondary transfer nip portion 17. At the secondary transfer nip portion 17, the timing of the recording material S and the full-color toner image coincides, and secondary transfer is performed in which the toner image is transferred from the intermediate transfer belt 9 to the recording material S. The recording material S is then transported to the fixing device 19, where the toner image is fixed to the recording material S by applying heat and pressure. After passing through the fixing device 19, the recording material S is transported to the discharge roller pair 20 and discharged onto the discharge tray 21 by the discharge roller pair 20.

[0022] 2, the image forming apparatus 100 is equipped with a control unit 800. The control unit 800 performs various controls of the image forming apparatus 100, such as image formation operations, and is configured by, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory), although these are not shown. The ROM and RAM store various programs and data for controlling the image forming apparatus 100, and the CPU can execute the various programs stored therein to operate the image forming apparatus 100.

[0023] In this embodiment, the drum unit and the developing unit deteriorate due to repeated image formation processes and require replacement or maintenance. The drum unit and the developing unit are in the form of cartridges so that the user can easily insert and remove them from the housing 100A for replacement or maintenance. Figure 3 shows the arrangement of the drum unit 23, the developing unit 24, and the exposure unit 4 when inserting and removing the drum unit 23 and the developing unit 24.

[0024] 3, when inserting or removing the drum unit 23 or the developing unit 24, the developing unit 24 and the exposure unit 4 are retracted from the drum unit 23 and are spaced apart from the photosensitive drum 2, unlike the state shown in FIG. 2. This is because if the developing unit 24 and the exposure unit 4 were positioned close to the photosensitive drum 2 when inserting or removing the drum unit 23 or the developing unit 24, dynamic interference during insertion or removal of the drum unit 23 or the developing unit 24 could damage the units or make it impossible to remove them. For this reason, the user is allowed to retract the developing unit 24 and the exposure unit 4 before inserting or removing the drum unit 23 or the developing unit 24.

[0025] <Exposure unit> Next, the exposure unit 4 will be described with reference to Fig. 3 and Fig. 4 to Fig. 12. As shown in Fig. 4, the exposure unit 4 as an exposure section includes a mounting substrate 50, a plurality of light-emitting elements 51 arranged on one side of the mounting substrate 50 in the direction of the rotation axis of the photosensitive drum 2, a lens assembly 52 in which a plurality of lenses that transmit light emitted from the light-emitting elements 51 are arranged, and a main body 54. The lens assembly 52 has a plurality of lenses arranged in the arrangement direction of the light-emitting elements 51. Note that, although light-emitting diodes (LEDs) are used as the light-emitting elements 51 in this embodiment, the present invention is not limited to this, and organic electroluminescence (EL) elements may also be used, for example.

[0026] A plurality of light-emitting elements 51 and a plurality of lenses are arranged on the mounting substrate 50 and the lens assembly 52, respectively, across the exposure range in the rotational axis direction of the photosensitive drum 2. Therefore, as shown in FIG. 5 , the mounting substrate 50 and the lens assembly 52 are formed in a shape that extends in the front-to-rear direction (longitudinal direction) along the rotational axis direction of the photosensitive drum 2. The mounting substrate 50 and the lens assembly 52 are held in place by being adhered to the main body 54 with high precision using an adhesive. The main body 54 is required to have high rigidity, and in this embodiment, a metal plate such as a galvanized steel plate or a cold-rolled steel plate bent into a substantially U-shaped cross section is used. The lens assembly 52 and the mounting substrate 50 are inserted into the main body 54 in order from the open side of the U and fixed with an adhesive.

[0027] As shown in FIG. 6A, a plurality of LED chips 53 are mounted on one surface of the mounting substrate 50, and an FFC (Flexible Flat Cable) connector 57 is mounted on the other surface of the mounting substrate 50. The FFC connector 57 is attached to the other surface of the mounting substrate 50 so that its longitudinal direction is aligned with the longitudinal direction of the mounting substrate 50. Wiring is formed on the mounting substrate 50 for supplying electrical signals to each LED chip 53 via the FFC connector 57. One end of a cable 58, such as a flexible flat cable or a wire harness, is connected to the FFC connector 57. As will be described in detail later, the exposure unit 4 is held in the cartridge tray 30 with one end of the cable 58 already connected to the FFC connector 57. After the cartridge tray 30 is attached to the housing 100A, the other end of the cable 58 is connected to a board connector 85 of the control board 500 (see FIG. 13). The other end of the cable 58 is provided so as to be freely connectable to the board connector 85.

[0028] As shown in FIG. 6(b), a plurality of LED chips 53 (53-1 to 53-29) each having a plurality of light-emitting elements 51 arranged thereon are arranged on the surface of the mounting substrate 50. Each LED chip 53 has 516 light-emitting elements 51 arranged in a row in the longitudinal direction. As shown in FIG. 6(c), the center-to-center distance "k2" between adjacent light-emitting elements 51 in the longitudinal direction of each LED chip (53-1, 53-2) corresponds to the resolution of the image forming apparatus 100. For example, if the resolution of the image forming apparatus 100 is "1200 dpi," the light-emitting elements 51 are arranged such that the center-to-center distance between adjacent light-emitting elements 51 in the longitudinal direction of the LED chip 53 is "21.16 μm." In this case, the exposure range of the exposure unit 4 is "approximately 314 mm." The photosensitive layer of the photosensitive drum 2 is formed with a width (longitudinal length) of 314 mm or more. For example, the length of the long side of an A4 size recording material S or the length of the short side of an A3 size recording material S is 297 mm, so the exposure unit 4 can expose recording materials S of A4 size and A3 size.

[0029] The LED chips 53 are alternately arranged in two rows in the direction of the rotation axis of the photosensitive drum 2. For example, as shown in FIG. 6(c), the odd-numbered LED chips (53-1, 53-3, ... 53-29) counting from the left are mounted in a row in the longitudinal direction of the mounting substrate 50 at intervals. In contrast, the even-numbered LED chips (53-2, 53-4, ... 53-28) are mounted in a row in the longitudinal direction of the mounting substrate 50 at intervals, at positions deviated from the row of the odd-numbered LED chips (53-1, 53-3, ... 53-29) in the direction of the rotation axis of the photosensitive drum 2. Furthermore, as shown in Figure 6(c), the odd-numbered LED chips (53-1, 53-3, ... 53-29) and the even-numbered LED chips (53-2, 53-4, ... 53-28) are mounted so that the center-to-center distance "k1" between the light-emitting element 51 arranged on the right end side of the odd-numbered LED chips (53-1, 53-3, ... 53-27) and the light-emitting element 51 arranged on the left end side of the odd-numbered LED chips (53-2, 53-4, ... 53-28) in the longitudinal direction of the LED chip 53 is equal to the center-to-center distance "k2" described above.

[0030] Next, the lens assembly 52 will be described. As shown in FIG. 6(d), a plurality of lenses 521 are arranged in two rows along the arrangement direction of the plurality of light-emitting elements 51 in the LED chip 53, corresponding to the odd-numbered LED chips (53-1, 53-3, . . . 53-29) and the even-numbered LED chips (53-2, 53-4, . . . 53-28). The lenses 521 are arranged alternately in one longitudinal row so that one lens 521 in the other row is in contact with both of the adjacent lenses 521. As shown in FIG. 6(e), the lenses 521 are cylindrical glass rod lenses. The material of the lenses 521 is not limited to glass, and they may be plastic. The shape of the lenses 521 is also not limited to cylindrical, and they may be polygonal prisms, such as hexagonal prisms.

[0031] The dotted line Z in FIG. 6(e) indicates the optical axis of the lens 521. The exposure unit 4 can be moved in a direction generally along the optical axis of the lens indicated by the dotted line Z by a movement mechanism (not shown). The optical axis of the lens 521 here refers to the line connecting the center of the light emission surface of the lens 521 and the focal point of the lens 521. The radiation light emitted from the plurality of light-emitting elements 51 is incident on the plurality of lenses 521 of the lens assembly 52. ​​The lenses 521 focus the incident radiation light on the surface of the photosensitive drum 2. The mounting position of the lens assembly 52 is adjusted during assembly of the exposure unit 4 so that the distance between the light-emitting surface of the light-emitting element 51 and the light incidence surface of the lens 521 is approximately equal to the distance between the light emission surface of the lens 521 and the surface of the photosensitive drum 2.

[0032] Fig. 7 is a perspective view showing two surfaces of the mounting board 50. As shown in Fig. 7, an FFC connector 57 and an IC (Integrated Circuit) 56 are mounted on two surfaces of the mounting board 50, closer to the front than the center in the longitudinal direction. The IC 56 drives each LED chip 53 on the mounting board 50 in accordance with a light emission control signal received from the control board 500 via the FFC connector 57, thereby turning on or off the light emitting element 51.

[0033] Fig. 8 is a perspective view showing a state in which the mounting board 50 is attached to the main body 54 in the exposure unit 4. Fig. 9 is an enlarged view showing a part of the exposure unit 4 shown in Fig. 8. As shown in Figs. 8 and 9, the boundary between the mounting board 50 and the main body 54 is sealed with a sealant 59. This prevents the light-emitting elements 51 from being contaminated with toner or dust. The sealant 59 only seals the boundary between the mounting board 50 and the main body 54, and the FFC connector 57, IC 56, and most of the mounting board 50 are exposed.

[0034] 10 is a perspective view showing a state in which the lens assembly 52 is further attached to the main body 54 in the exposure unit 4 from the state shown in FIG. 8. As shown in FIG. 10, the boundary between the lens assembly 52 and the main body 54 is also sealed with a sealant 59, similar to the boundary between the mounting substrate 50 and the main body 54, to prevent the light emitting element 51 from being contaminated with toner or dust.

[0035] FIG. 11 is a perspective view showing two sides of the exposure unit 4, and FIG. 12 is an enlarged view showing a portion of the two sides of the exposure unit 4. As shown in FIGS. 11 and 12, a support member 55 having a generally U-shaped cross section is integrally provided on the main body 54 at the opening side of the U-shaped opening of the main body 54. An opening 55A communicating between the inside and outside of the support member 55 is formed in the support member 55 at a position facing the two sides (rear side) of the mounting substrate 50 on the main body 54. As shown in FIG. 12, a shielding wall 76 is provided on the support member 55, and the shielding wall 76 separates an area where the opening 55A is formed from an area where the FFC connector 57 is disposed. In this manner, the exposure unit 4 is configured as an integrated head unit including the mounting substrate 50 on which a plurality of light-emitting elements 51 are mounted, the lens assembly 52 in which a plurality of lenses 521 are arranged in parallel, the main body 54, and the support member 55.

[0036] Next, the electrical connection between the exposure unit 4 and the control board 500 using the cable 58 will be described with reference to Figures 13 to 15. Figure 13 shows a state in which the exposure unit 4 and the control board 500 are electrically connected by the cable 58 before the drum unit 23 and the developing unit 24 are attached to the cartridge tray 30 attached to the housing 100A.

[0037] As described above, the cartridge tray 30 serving as a holder holds the exposure units 4 of the image forming units 1Y to 1K lined up in the left-right direction, and one end of the cable 58 is already connected to the FFC connector 57 of the exposure unit 4. As shown in Fig. 13, the cable 58, one end of which is already connected to the FFC connector 57, has the other end detachably attached to the board connector 85 of the control board 500. By connecting the other end of the cable 58 to the board connector 85, the exposure units 4 and the control board 500 are electrically connected, and a light emission control signal is sent from the control board 500 to the exposure units 4 via the cable 58.

[0038] When the exposure unit 4 is held in the cartridge tray 30, the FFC connector 57 of the exposure unit 4 is located upstream (front) in the insertion direction of the cartridge tray 30 into the housing 100A. Cable 58 runs from the FFC connector 57 along the front side of the cartridge tray 30 from right to left of the image forming apparatus 100. This is because, as shown in FIG. 14 , in this embodiment, the control board 500, to which cable 58 is connected, is disposed on a metal connecting stay 100C, which is part of the housing 100A, on the left side of the image forming apparatus 100. The connecting stay 100C extends from a front support column 100B, which is part of the housing 100A, in the insertion direction (see arrow D) and connects the front support column 100B to a rear support column (not shown). The cartridge tray 30 can be inserted through an opening 1001 formed in a front side plate 100D.

[0039] The cartridge tray 30 has, at its front end, holding guides 60 in numbers corresponding to the exposure units 4. The holding guides 60 are elastic and press the cable 58 from above downward so that the cable 58, which is routed from right to left, does not move freely unless a force equal to or greater than a predetermined value is applied to the cable 58 from the outside. In this embodiment, from right to left, the first holding guide 60 presses one cable 58, the second holding guide 60 presses two overlapping cable 58, the third holding guide 60 presses three overlapping cable 58, and the fourth holding guide 60 presses four overlapping cable 58.

[0040] <FFCガイド> The multiple (four in this example) bundled cables 58 routed by the holding guide 60 are held by one FFC guide 83. The FFC guide 83 is made of resin and is engaged with a connecting stay 100C, which is a part of the housing 100A, when the cartridge tray 30 is attached to the housing 100A. When the FFC guide 83 is engaged with the connecting stay 100C, the left end side (stay side) of the bundled cables 58 is routed from the cartridge tray 30 to the outside of the connecting stay 100C. Then, while engaged with the connecting stay 100C, the FFC guide 83 guides the held bundled cables 58 along the connecting stay 100C from the front side to the rear side toward the control board 500. The FFC guide 83 holds the multiple bundled cables 58 by bending them together so that the bundled cables 58 routed from right to left by the holding guide 60 face from the front side to the rear side. In this way, the FFC guide 83 is locked to the connecting stay 100C, so that the cable 58 can be easily connected to the control board 500 when the image forming apparatus 100 is assembled.

[0041] As described above, the FFC guide 83 is engaged with the connecting stay 100C when the cartridge tray 30 is attached to the housing 100A, but is engaged with the cartridge tray 30 until the cartridge tray 30 is attached to the housing 100A. That is, the FFC guide 83 is engaged with the cartridge tray 30 before it is attached to the housing 100A, and after the cartridge tray 30 is attached to the housing 100A, it is removed from the cartridge tray 30 and engaged with the connecting stay 100C. The FFC guide 83 will be described in detail with reference to Figures 15 to 17.

[0042] 15 , FFC guide 83 collectively holds a plurality of cables 58 on the first surface 83A side. FFC guide 83, which serves as a cable holding member, has two FFC holding portions 93 formed to be elastically deformable, and these FFC holding portions 93 press and sandwich cable 58 between them and first surface 83A, thereby holding cable 58 on the first surface 83A side. FFC guide 83 also has an upper guide 941 and a lower guide 942 erected from the surface on the first surface 83A side. These upper guide 941 and lower guide 942 form a guide path 830, and cable 58 is bent along guide path 830 and guided from a guide inlet 831 to a guide outlet 832. In this embodiment, as described above, the guide path 830 is formed by the upper guide 941 and the lower guide 942 so as to guide the bundled wires 58 from the front side to the rear side along the connection stay 100C when the FFC guide 83 is engaged with the connection stay 100C. The two FFC holding portions 93 are formed in a shape that protrudes from the upper guide 941 and the lower guide 942 toward the guide path 830. Note that although the case where two FFC holding portions 93 are provided is shown here, three or more FFC holding portions 93 may be provided.

[0043] The FFC guide 83 also has a first locking claw 87 as a protruding portion (first protruding portion) protruding from a second surface opposite the first surface 83A. The first locking claw 87 has a first locking portion 89 for locking with the connecting stay 100C and a second locking portion 88 for locking with the cartridge tray 30. The FFC guide 83 also has a second locking claw 90 as a second protruding portion protruding from the second surface and locking with a third locked portion of the connecting stay 100C different from the first locked portion locked by the first locking portion 89 when the FFC guide 83 is locked with the connecting stay 100C by the first locking portion 89. The first locking claw 87 and the second locking claw 90 lock onto the connecting stay 100C and the cartridge tray 30 when the FFC guide 83 is moved from front to rear relative to the connecting stay 100C and the cartridge tray 30, and when the FFC guide 83 is moved from rear to front relative to the connecting stay 100C and the cartridge tray 30, the locking with the connecting stay 100C and the cartridge tray 30 is released.

[0044] Figures 16(a) and 16(b) show the state in which the FFC guide 83 and the connecting stay 100C are engaged. Figure 16(a) is a left side view, and Figure 16(b) is a cross-sectional view taken along the arrow FF in Figure 16(a). In this embodiment, the FFC guide 83 is engaged with the connecting stay 100C at a position upstream of the control board 500 in the insertion direction of the cartridge tray 30 into the casing 100A (see Figure 13).

[0045] As shown in Figures 16(a) and 16(b), the FFC guide 83 is locked to the connecting stay 100C by a first locking claw 87 that is elastically deformable. As shown in Figure 16(b), the first locking claw 87 has a first locking portion 89 and a second locking portion 88 at different heights from the second surface 83B of the FFC guide 83, and the FFC guide 83 is locked to a first locked portion 201 of the connecting stay 100C by the first locking portion 89 of the first locking claw 87. The locking direction of the first locking portion 89 with respect to the first locked portion 201 is the same as the insertion direction of the cartridge tray 30 into the casing 100A. The height of the first locking portion 89 from the second surface 83B is adjusted according to the thickness of the first locking portion 200. When the first locking portion 89 contacts the first locked portion 201 with its surface (first contact surface), the second surface 83B and the first locking portion 89 sandwich the connecting stay 100C, and the FFC guide 83 is locked to the connecting stay 100C.

[0046] Furthermore, with the first locking portion 89 of the first locking claw 87 locked to the first locked portion 201, the FFC guide 83 is also locked to the connecting stay 100C by the second locking claw 90, which is formed to be elastically deformable. The FFC guide 83 is locked to the third locked portion 203 of the connecting stay 100C by the second locking claw 90. The second locking claw 90 protrudes from the second surface 83B so that it locks to the third locked portion 203 at the same height as the first locking portion 89 from the second surface 83B. In other words, the first locked portion 201 and the third locked portion 203 of the connecting stay 100C may have the same thickness. The FFC guide 83 is locked to the connecting stay 100C by sandwiching the connecting stay 100C between the second locking claw 90 and the second surface 83B.

[0047] Furthermore, the FFC guide 83 has a snap fit 92 protruding from the second surface 83B as a housing movement restricting portion. The snap fit 92 is formed to be elastically deformable, and when the first locking portion 89 is locked with the first locked portion 201 and when the second locking claw 90 is locked with the third locked portion 203, the snap fit 92 is locked with the fourth locked portion 204 of the connecting stay 100C. The snap fit 92 has an arm portion 92a that elastically deforms in a direction intersecting the insertion direction of the cartridge tray 30 into the housing 100A and a direction intersecting the up-down direction, and a protrusion portion 92b that protrudes from the tip of the arm portion 92a and can be locked with the fourth locked portion 204. When the protrusion 92b is locked with the fourth locked portion 204, movement of the FFC guide 83 relative to the connecting stay 100C is restricted, and the locked state between the first locking portion 89 and the first locked portion 201 and the locked state between the second locking claw 90 and the second locked portion 202 are not released. In other words, the snap fit 92 functions to prevent the FFC guide 83 from coming off the connecting stay 100C by itself.

[0048] Next, Figures 17(a) and 17(b) show the locked state between the FFC guide 83 and the cartridge tray 30. Figure 17(a) is a top view, and Figure 17(b) is a cross-sectional view taken along the arrow EE in Figure 17(a).

[0049] In this embodiment, the FFC guide 83 is locked to the cartridge tray 30 by the first locking claw 87 at a position where it covers part of the open upper end surface of the cartridge tray 30 on the developing unit side. However, as shown in FIGS. 17(a) and 17(b), unlike when the FFC guide 83 is locked to the connecting stay 100C, the second locking portion 88 of the first locking claw 87 is locked to the second locked portion 202 of the cartridge tray 30 by the second locking portion 88 of the first locking claw 87. When the cartridge tray 30 is inserted into the housing 100A, the second locking portion 88 comes into contact with and locks to the second locked portion 202 at a surface (second contact surface) parallel to the surface (first contact surface) where the first locking portion 89 comes into contact with the first locked portion 201. The locking direction of the second locking portion 88 with respect to the second locked portion 202 is the same as the locking direction of the first locking portion 89 with respect to the first locked portion 201.

[0050] To ensure strength, the thickness of the resin cartridge tray 30 at the portion where the FFC guide 83 is locked is thicker than the thickness of the metal connecting stay 100C at the portion where the FFC guide 83 is locked. Therefore, in this embodiment, the FFC guide 83 is locked to the first locked portion 201 of the connecting stay 100C by the first locking portion 89 of the first locking claw 87, which is lower in height from the second surface 83B, and is locked to the second locked portion 202 of the cartridge tray 30 by the second locking portion 88 of the first locking claw 87, which is higher in height from the second surface 83B.

[0051] The FFC guide 83 also has an elastically deforming portion 96 protruding from the second surface 83B and serving as a holder movement restricting portion. The elastically deforming portion 96 of the FFC guide 83 is elastically deformable and, when the second locking portion 88 is locked with the second locked portion 202, locks with the fifth locked portion 205 of the cartridge tray 30. The elastically deforming portion 96 has a protrusion 96a that can lock with the fifth locked portion 205 in a direction intersecting the insertion direction of the cartridge tray 30 into the housing 100A and a direction intersecting the up-down direction. When the protrusion 96a is locked with the fifth locked portion 205, movement of the FFC guide 83 relative to the cartridge tray 30 is restricted, and the locked state between the second locking portion 88 and the second locked portion 202 is not released. In other words, the elastically deforming portion 96 functions as a retainer for the FFC guide 83 to prevent the FFC guide 83 from accidentally coming off the cartridge tray 30.

[0052] FIG. 18 shows a comparative example in which, when the cartridge tray 30 is inserted into the housing 100A, the cable 58 before being connected to the control board 500 interferes with the housing 100A. In the comparative example shown in FIG. 18, the FFC guide 83 is engaged with the left side wall 301 of the cartridge tray 30 before the cartridge tray 30 is attached to the housing 100A. In this case, when the cartridge tray 30 is inserted through the opening 1001 of the front side panel 100D, the other end of the cable 58 that is not held by the FFC guide 83 is likely to protrude outside the cartridge tray 30 as viewed from the front. If the cartridge tray 30 is inserted into the housing 100A with the other end of the cable 58 protruding outside the cartridge tray 30, the cable 58 may come into contact with a part of the housing 100A, such as the front support column 100B, and the cable 58 may be damaged or broken. In contrast, in this embodiment, as described above, the FFC guide 83 is engaged with the cartridge tray 30 at a position that covers part of the upper end surface on the development unit side, so the cable 58 is less likely to protrude outside the cartridge tray 30.

[0053] As described above, in this embodiment, the FFC guide 83 holding the cable 58 has the first locking claw 87, and the first locking claw 87 has the first locking portion 89 for locking with the connecting stay 100C and the second locking portion 88 for locking with the cartridge tray 30. Therefore, the FFC guide 83 can be locked with the cartridge tray 30 before it is attached to the housing 100A, and after the cartridge tray 30 is attached to the housing 100A, it can be removed from the cartridge tray 30 and locked with the connecting stay 100C. In this way, the FFC guide 83 can be locked in a temporary position on the cartridge tray 30 that is different from its normal position, so that the cable 58 before it is connected to the control board 500 does not interfere with the housing 100A when the cartridge tray 30 is inserted into the housing 100A, thereby preventing the cable 58 from being damaged or broken. Furthermore, one FFC guide 83 can be used in common for the connecting stay 100C and cartridge tray 30 having different thicknesses at the locking portion, which allows for a reduction in the number of parts and a reduction in costs.

[0054] <Other embodiments> In the above-described embodiment, the first locking portion 89 of the first locking claw 87 is configured to lock onto the connecting stay 100C, and the second locking portion 88 is configured to lock onto the cartridge tray 30, but this is not limitative. For example, depending on the thickness of the connecting stay 100C and the thickness of the cartridge tray 30, the second locking portion 88 of the first locking claw 87 may be configured to lock onto the connecting stay 100C, and the first locking portion 89 of the first locking claw 87 may be configured to lock onto the cartridge tray 30.

[0055] In the above-described embodiment, an intermediate transfer type image forming apparatus 100 is described as an example in which a toner image is primarily transferred from the photosensitive drum 2 of each color to the intermediate transfer belt 9, and then secondarily transferred from the intermediate transfer belt 9 to the recording material S. However, the present invention is not limited to this. The above-described embodiment can also be applied to a direct transfer type image forming apparatus in which a toner image is directly transferred from the photosensitive drum 2 of each color that rotates while carrying a toner image to the recording material S. [Explanation of symbols]

[0056] 2...photosensitive member (photosensitive drum), 4...exposure section (exposure unit), 30...holding body (cartridge tray), 51...light-emitting element, 58...cable, 83...cable holding member (FFC guide), 87...protruding portion (first protruding portion, first locking claw), 88...second locking portion, 89...first locking portion, 90...second protruding portion (second locking claw), 92...housing movement restricting portion (snap fit), 96...holding body movement restricting portion (elastic deformation portion), 100...image forming apparatus, 100A...housing, 201...first locked portion, 202...second locked portion, 203...third locked portion, 204...fourth locked portion, 205...fifth locked portion, 500...control board, S...recording material

Claims

1. An image forming apparatus for forming a toner image on a recording material, The housing and A photoreceptor; an exposure unit having a plurality of light-emitting elements for irradiating the photosensitive member with light to expose it; a holder that holds the exposure unit and is insertable into the housing; a control board provided in the housing and controlling the exposure unit; a bundle of wires, one end of which is connected to the exposure unit and the other end of which is connectable to the control board, electrically connecting the exposure unit and the control board; a cable holder for holding the cable bundle, the cable holding member has a protruding portion that protrudes from a second surface opposite to a first surface that holds the cable, and that is engaged with a first engaged portion of the housing by a first engaging portion; The protruding portion has a second locking portion for locking onto a second locked portion of the holder at a position where the height from the second surface is different from that of the first locking portion. An image forming apparatus characterized by:

2. the first engaging portion is in contact with the first engaged portion at a first contact surface and is engaged with the housing; When the holder is inserted into the housing, the second locking portion contacts the second locked portion at a second contact surface parallel to the first contact surface, and is locked to the holder, and the locking direction of the second locking portion with respect to the second locked portion is the same as the locking direction of the first locking portion with respect to the first locked portion.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

3. the protruding portion is a first protruding portion, the cable holder has a second protruding portion that protrudes from the second surface and is engaged with a third engaged portion of the housing when the first engaging portion is engaged with the first engaged portion.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

4. the second protruding portion is engaged with the third engaged portion at a height from the second surface that is the same as the height of the first engaged portion; 4. The image forming apparatus according to claim 3, wherein the image forming apparatus is a recording medium.

5. the cable holder includes a housing movement restricting portion that, when the first locking portion is locked to the first locked portion, locks onto a fourth locked portion of the housing in a direction intersecting the insertion direction of the holder into the housing and a direction intersecting the up-down direction, restricts movement of the cable holder relative to the housing so that the first locking portion and the first locked portion are not disengaged.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

6. the cable holder includes a holder movement restricting portion that restricts movement of the cable holder relative to the holder so that the second locking portion and the second locked portion are disengaged from each other by engaging with the fifth locked portion of the holder in a direction intersecting the insertion direction of the holder into the housing and a direction intersecting the up-down direction when the second locking portion is locked with the second locked portion.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

7. the housing has a support pillar disposed upstream of the holder in the insertion direction, and a stay extending from the support pillar in the insertion direction, The control board is provided on the stay, The first locked portion is provided on the stay.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

8. the holder holds a plurality of exposure units arranged side by side in a direction intersecting the insertion direction, and guides a plurality of bundled wires connected to each of the exposure units toward the stay on the upstream side of the insertion direction, the cable holder collectively holds the plurality of cable bundles guided by the holder, and when engaged with the housing, changes the orientation of the plurality of cable bundles from a direction intersecting the insertion direction to the insertion direction, and guides the cable bundles from the upstream side of the insertion direction toward the control board.

8. The image forming apparatus according to claim 7,

Images