Optical scanning device and image forming apparatus including the same

Abstract

To provide an optical scanner capable of suppressing the malfunction of a cleaning holder and improving the attaching / detaching workability of the cleaning holder, and to provide an image forming apparatus equipped with the optical scanner.SOLUTION: The optical scanning device includes a housing, a light transmitting member, a linear member, a driving unit, a plurality of first guide rails, a plurality of second guide rails, one or more cleaning holders, a cleaning member, and a stopper. The housing includes a rib formed along a peripheral edge portion of an upper surface of the housing, and a missing portion formed between an end portion of the first guide rail on the second direction side and the rib. The cleaning holder includes a first restricting portion that engages with the first guide rail in the up-down direction, and a second restricting portion that comes into contact with a side surface of the second guide rail.SELECTED DRAWING: Figure 12

Description

[Technical Field]

[0001] The present invention relates to an optical scanning device that forms an electrostatic latent image by irradiating light onto an image carrier in an electrophotographic image forming apparatus, and to an image forming apparatus equipped with an optical scanning device. [Background technology]

[0002] An optical scanning device irradiates a charged image carrier with light to form an electrostatic latent image on the image carrier. Optical scanning devices are known to have a configuration including a housing, a transparent member, a linear member, a drive member, a guide rail, a cleaning holder, a cleaning member, and a stopper. Because the cleaning member needs to be replaced after a certain period of use, it is necessary to improve the ease of attaching and detaching the cleaning member.

[0003] Patent Document 1 discloses a configuration having a guide rail with which an engaging portion of a cleaning holder (holding member) engages, and a groove formed below the guide rail, the width of which is wider than the longitudinal width of the guide rail. When the cleaning holder moves from the longitudinal end of the guide rail to the side opposite the longitudinal center and the engaging portion passes through the groove, the engaging portion of the cleaning holder and the engaging portion of the guide rail partially disengage, and the guide rail no longer restricts the cleaning holder from moving upward. The guide rail has an inclined portion that is inclined so that the contact position with the engaging portion shifts upward from a predetermined position in the longitudinal direction toward the end.

[0004] In the configuration of Patent Document 1, when the cleaning holder reaches the longitudinal end of the guide rail and then scans to the opposite side, the inclined portion on the guide rail and the inclined portion on the cleaning holder may get caught, causing the cleaning holder to stop or the gear teeth to skip.

[0005] Patent Document 2 discloses an optical scanning device that includes a guide rail that extends in the extension direction of a transparent member and a cleaning holder that is fixed to the linear member and moves along the guide rail when the linear member travels in a circular motion, with one end of the guide rail in the longitudinal direction being open. According to the configuration of Patent Document 2, the cleaning holder can be easily incorporated into the guide rail by sliding the cleaning holder engagement part in the extension direction of the guide rail while engaging the guide rib from the open side of the guide rail. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2020-91371 [Patent Document 2] Japanese Patent Application Publication No. 2024-22975 Summary of the Invention [Problem to be solved by the invention]

[0007] In the configuration of Patent Document 2, when the cleaning holder stops at the end of the guide rail, a rotational moment acts on the cleaning holder in the pulling direction, which can cause the cleaning holder to rotate. In this case, if the cleaning holder is moved in the opposite direction while rotated, the cleaning holder can get caught on the end of the guide rail, resulting in a malfunction. While this problem can be solved by extending the guide rail to the open side, it makes removing the cleaning holder more difficult, which is a trade-off with the ease of removing the cleaning holder.

[0008] In view of the above problems, the present invention aims to provide an optical scanning device and an image forming apparatus equipped with the same that can suppress malfunction of a cleaning holder that cleans a transparent member and also improve the ease of attaching and detaching the cleaning holder. [Means for solving the problem]

[0009] In order to achieve the above object, a first aspect of the present invention is an optical scanning device that forms an electrostatic latent image by irradiating an image carrier with laser light. The optical scanning device includes a housing, a transparent member, a linear member, a drive unit, a plurality of first guide rails, a plurality of second guide rails, one or more cleaning holders, a cleaning member, and a stopper. The housing has a laser light emission opening that extends in the main scanning direction of the laser light corresponding to the image carrier. The transparent member is transparent to the laser light, extends in the main scanning direction of the laser light, and seals the laser light emission opening. The linear member is stretched in an annular shape on the housing. The drive unit causes the linear member to travel in a predetermined direction. The plurality of first guide rails are formed on the top surface of the housing and extend in the extension direction of the transparent member. The plurality of second guide rails are formed on the top surface of the housing and extend parallel to the first guide rails. The cleaning holder is fixed to the linear member and moves on the permeable member along the first and second guide rails in a first direction and a second direction opposite to the first direction when the linear member is moved by the drive unit. The cleaning member is fixed to the cleaning holder and cleans the permeable member by sliding against the permeable member as the cleaning holder moves. The stopper is formed on the end of the first guide rail on the first direction side and restricts movement of the cleaning holder in the first direction. The housing has a rib formed along the periphery of the top surface of the housing, and a cutout formed between the end of the first guide rail on the second direction side and the rib, which can release the engagement between the first guide rail and the first restricting part. The cleaning holder has a first restricting part that engages with the first guide rail in the up-down direction to restrict upward movement of the cleaning holder, and a second restricting part that contacts the side of the second guide rail to restrict rotation of the cleaning holder. [Effects of the Invention]

[0010] According to the first configuration of the present invention, the cleaning holder has a second restricting portion that contacts the side surface of the second guide rail to restrict rotation of the cleaning holder. Therefore, when the cleaning holder is stopped at the end of the first guide rail on the second direction side, the cleaning holder is held vertically without tilting relative to the direction of movement. Therefore, when the cleaning holder starts moving in the first direction from a stopped state, it is possible to effectively prevent the cleaning holder from getting caught in the missing portion of the first guide rail, preventing malfunctions. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a cross-sectional view showing the overall configuration of an image forming apparatus 1 equipped with an optical scanning device 12 according to the present invention. [Figure 2] 1 is a perspective view of an optical scanning device 12 according to an embodiment of the present invention; [Figure 3] 1 is a plan view of the optical scanning device 12 of this embodiment seen from above. [Figure 4] 10 is a cross-sectional view of the cover 12c of the optical scanning device 12 according to the embodiment, showing the attachment portion of the cleaning holder 511, viewed from the movement direction of the cleaning holder 511. [Figure 5] 1 is a cross-sectional view of a cleaning holder 511 attached to a cover portion 12c of an optical scanning device 12 according to an embodiment of the present invention, viewed from the direction of movement of the cleaning holder 511. [Figure 6] FIG. 10 is a partial perspective view of the cover 12c of the optical scanning device 12 of the present embodiment, showing the periphery of the end portion of the first guide rail 61 on one side to which the cleaning holder 511 is connected, on the detection unit 56 side. [Figure 7] FIG. 10 is a partial perspective view of the cover 12c of the optical scanning device 12 of the present embodiment, showing the periphery of the end portion of the first guide rail 61 on the other side, to which the cleaning holder 511 is connected, on the detection unit 56 side. [Figure 8] FIG. 10 is a plan view of the optical scanning device 12 of the present embodiment, showing a state in which the cleaning holder 511 is detected by the detection unit 56. [Figure 9] FIG. 10 is a plan view of the optical scanning device 12 of the present embodiment, showing a state in which the cleaning holder 512 is detected by the detection unit 56. [Figure 10] FIG. 1 is a block diagram showing an example of a control path used in the image forming apparatus 1. [Figure 11] 1 is a partial plan view of the end portion on the X2 side of the optical scanning device 12 of this embodiment, viewed from above. [Figure 12] FIG. 10 is a partial plan view of the X2-side end of the optical scanning device 12 of this embodiment, seen from above, illustrating a state in which the cleaning holder 511 is stopped at the X2-side end of the first guide rail 61. [Figure 13] FIG. 13 is a diagram showing a state in which the cleaning holder 511 starts to move to the X1 side of the first guide rail 61 from the state in FIG. 12. [Figure 14] FIG. 10 is a schematic diagram showing a configuration in which the second restricting portion 51c of the cleaning holder 511 abuts against the outer side of the second guide rail 63. [Figure 15] 15 is a diagram showing a state in which a clockwise rotation moment is generated around point P1 when cleaning holder 511 is moved in the X2 direction in the configuration of FIG. [Figure 16] FIG. 16 is a diagram showing a state in which a rotation moment is generated in the counterclockwise direction around point P2 when the cleaning holder 511 is further moved in the X2 direction from the state of FIG. 15. [Figure 17] FIG. 10 is a schematic diagram showing a configuration in which the second restricting portion 51c of the cleaning holder 511 abuts against the inner side of the second guide rail 63. [Figure 18] FIG. 18 is a diagram showing a state in which a clockwise rotation moment is generated around point P3 when cleaning holder 511 is moved in the X2 direction in the configuration of FIG. 17. [Figure 19] FIG. 19 is a diagram showing a state in which a rotation moment is generated in the counterclockwise direction around point P4 when the cleaning holder 511 is further moved in the X2 direction from the state of FIG. 18. [Figure 20] A partially enlarged view of the cleaning member 53 and its surroundings on one side of the cleaning holder 511 in FIG. 5. [Figure 21] 6 is a partially enlarged view of the cleaning member 53 and its surroundings on the other side of the cleaning holder 511 in FIG. [Figure 22]FIG. 10 is a partial plan view of the X2-side end of the optical scanning device 12 of this embodiment, seen from above, illustrating a state in which the cleaning holders 511 and 512 are stopped at the X2-side end of the first guide rail 61. [Figure 23] 23 shows a state in which the pulley 57 on the X2 side of the optical scanning device 12 is removed from the state shown in FIG. 22 and the cleaning holders 511 and 512 are moved in the X2 direction. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing a schematic overall configuration of an image forming apparatus 1 equipped with an optical scanning device 12 of the present invention. The image forming apparatus 1 is a tandem color printer. The image forming apparatus 1 is equipped with rotatable photosensitive drums 11a-11d as image carriers. The photosensitive drums 11a-11d are made of organic photosensitive materials (OPC photosensitive materials) having an organic photosensitive layer formed thereon, or amorphous silicon photosensitive materials having an amorphous silicon photosensitive layer formed thereon. The photosensitive drums 11a-11d are arranged in tandem corresponding to the colors yellow, magenta, cyan, and black.

[0013] Developing device 2a, charger 13a, and cleaning device 14a are disposed around photosensitive drum 11a. Similarly, developing devices 2b to 2d, chargers 13b to 13d, and cleaning devices 14b to 14d are disposed around photosensitive drums 11b to 11d, respectively. In addition, optical scanning device 12 is disposed below developing devices 2a to 2d.

[0014] The developing devices 2a to 2d are disposed to the right of the photosensitive drums 11a to 11d, respectively. The developing devices 2a to 2d face the photosensitive drums 11a to 11d, respectively, and supply toner to the photosensitive drums 11a to 11d. In this specification, right and left refer to the right and left in the drawings.

[0015] The chargers 13a to 13d are disposed upstream of the developing devices 2a to 2d in the direction of rotation of the photosensitive drums 11a to 11d, and face the surfaces of the photosensitive drums 11a to 11d, respectively. The chargers 13a to 13d uniformly charge the surfaces of the photosensitive drums 11a to 11d, respectively.

[0016] The optical scanning device 12 irradiates (optical scans) the surfaces of the photosensitive drums 11a to 11d, which have been uniformly charged by the chargers 13b to 13d, with light based on image data such as characters and pictures input to an image input unit (not shown) from a personal computer or the like, and forms electrostatic latent images on the surfaces of the photosensitive drums 11a to 11d.

[0017] The housing 12a of the optical scanning device 12 includes a storage section 12b with one surface open, and a cover section 12c that covers the opening. The storage section 12b incorporates a scanning optical system 120 therein. The cover section 12c is formed with exit openings 12d (see FIG. 4) through which light (laser light) is emitted from the scanning optical system 120 corresponding to the photosensitive drums 11a to 11d. Furthermore, as will be described later, each of the exit openings 12d is covered with a transparent member 52. The transparent member 52 is transparent to the light emitted from the scanning optical system 120.

[0018] The scanning optical system 120 includes a laser light source and a polygon mirror. The scanning optical system 120 also includes at least one reflecting mirror and a lens (neither of which are shown) corresponding to each of the photosensitive drums 11a to 11d. Laser light emitted from the laser light source is irradiated onto the surfaces of the photosensitive drums 11a to 11d from downstream of the chargers 13a to 13d in the rotation direction of the photosensitive drums 11a to 11d via the polygon mirror, the reflecting mirror group, and the lens group. As a result, electrostatic latent images are formed on the surfaces of the photosensitive drums 11a to 11d. These electrostatic latent images are developed into toner images by the developing devices 2a to 2d.

[0019] An endless intermediate transfer belt 17 is stretched over a tension roller 6, a drive roller 25, and a driven roller 27. When the drive roller 25 is rotated by a motor (not shown), the intermediate transfer belt 17 is driven to circulate in the clockwise direction in FIG.

[0020] The photosensitive drums 11a to 11d are arranged adjacent to each other along the transport direction (the direction of the arrow in FIG. 1) below the intermediate transfer belt 17. The photosensitive drums 11a to 11d are in contact with the intermediate transfer belt 17. The primary transfer rollers 26a to 26d face the photosensitive drums 11a to 11d, respectively, with the intermediate transfer belt 17 sandwiched therebetween. The primary transfer rollers 26a to 26d are each pressed against the intermediate transfer belt 17 and form a primary transfer portion together with the photosensitive drums 11a to 11d. At this primary transfer portion, toner images are transferred onto the intermediate transfer belt 17. More specifically, a primary transfer voltage is applied to the primary transfer rollers 26a to 26d, so that the toner images on the photosensitive drums 11a to 11d are sequentially transferred to the intermediate transfer belt 17 at a predetermined timing. As a result, a full-color toner image is formed on the surface of the intermediate transfer belt 17, in which toner images of four colors, yellow, magenta, cyan, and black, are superimposed in a predetermined positional relationship.

[0021] The secondary transfer roller 34 faces the drive roller 25 with the intermediate transfer belt 17 sandwiched therebetween. The secondary transfer roller 34 is pressed against the intermediate transfer belt 17 and forms a secondary transfer section together with the drive roller 25. In this secondary transfer section, a secondary transfer voltage is applied to the secondary transfer roller 34, so that the toner image on the surface of the intermediate transfer belt 17 is transferred to the paper P. After the toner image is transferred, a belt cleaning device 31 cleans off any toner remaining on the intermediate transfer belt 17.

[0022] A paper feed cassette 32 is disposed at the bottom within the image forming apparatus 1. The paper feed cassette 32 can store multiple sheets of paper P. A stack tray 35 for manual paper feed is disposed to the right of the paper feed cassette 32. A first paper transport path 33 is disposed to the left of the paper feed cassette 32. The first paper transport path 33 transports paper P fed from the paper feed cassette 32 to the secondary transfer unit. A second paper transport path 36 is disposed to the left of the stack tray 35. The second paper transport path 36 transports paper fed from the stack tray 35 to the secondary transfer unit. Furthermore, a fixing unit 18 and a third paper transport path 39 are disposed at the upper left within the image forming apparatus 1. The fixing unit 18 performs a fixing process on paper P on which an image has been formed. The third paper transport path 39 transports paper P after the fixing process to a paper discharge unit 37.

[0023] The sheets P stored in the sheet cassette 32 are fed one by one to the first sheet transport path 33 by a pickup roller 33b and a pair of separating rollers 33a.

[0024] The first paper transport path 33 and the second paper transport path 36 merge before (upstream from) the pair of registration rollers 33c. The pair of registration rollers 33c transports the paper P to the secondary transfer unit in accordance with the timing of the image formation operation on the intermediate transfer belt 17 and the paper feeding operation to the secondary transfer unit. The full-color toner image on the intermediate transfer belt 17 is secondarily transferred onto the paper P transported to the secondary transfer unit by the secondary transfer roller 34 to which a secondary transfer voltage is applied. The paper P to which the full-color toner image has been transferred is transported to the fixing unit 18.

[0025] The fixing unit 18 includes a fixing belt heated by a heater, a fixing roller in contact with the inside of the fixing belt, and a pressure roller that is pressed against the fixing roller across the fixing belt. The fixing unit 18 heats and presses the paper P onto which the toner image has been transferred, thereby carrying out the fixing process. The paper P onto which the toner image has been fixed in the fixing unit 18 is turned over as necessary in the fourth paper transport path 40. The paper P is then transported again to the secondary transfer unit via the registration roller pair 33c, and a new toner image is secondarily transferred onto the back side of the paper P by the secondary transfer roller 34, and fixed in the fixing unit 18. The paper P with the fixed toner image passes through the third paper transport path 39 and is discharged to the paper discharge unit 37 by the discharge roller pair 19.

[0026] Next, the optical scanning device 12 will be described with reference to FIGS. 2 to 9. FIG. 2 is a perspective view of the optical scanning device 12 according to one embodiment of the present invention. FIG. 3 is a plan view of the optical scanning device 12 according to this embodiment, viewed from above. FIGS. 4 and 5 are cross-sectional views of the attachment portion of the cover portion 12c of the optical scanning device 12 according to this embodiment, to which the cleaning holder 511 is attached, and the cleaning holder 511 attached to the cover portion 12c, viewed from the direction of movement of the cleaning holder 511. FIGS. 6 and 7 are partial perspective views of the periphery of the end portions of the first rails 61 on the detection unit 56 side on one and the other sides to which the cleaning holder 511 is connected, respectively. FIGS. 8 and 9 are plan views of the optical scanning device 12. Note that the second guide rails 63a and 63b are omitted from FIGS. 8 and 9.

[0027] In the following drawings, the extension direction of the transparent member 52 is designated as the X direction, the direction in which the cleaning holders 511 and 512 approach the detection unit 56 is designated as the X1 direction (first direction), and the direction in which they move away from the detection unit 56 is designated as the X2 direction (second direction). The parallel arrangement direction of the transparent member 52 (the longitudinal direction of the cleaning holders 511 and 512) is designated as the Y direction, with Y1 designated as one side of the parallel arrangement direction of the transparent member 52 and Y2 designated as the other side of the parallel arrangement direction of the transparent member 52. The shapes and positional relationships of the various components will be described with the cleaning holders 511 and 512 positioned upward relative to the cover 12c. The terms "upward and downward" are used merely for the purpose of explanation and do not limit the orientation of the optical scanning device 12 when incorporated into the image forming apparatus 1.

[0028] The optical scanning device 12 includes a housing 12a, a transparent member 52, a linear member 54, a motor (drive unit) 55, a first guide rail 61, a stopper 62, a second guide rail 63, cleaning holders 511, 512, a cleaning member 53, a detection unit 56, and a control unit 90 (see Figure 10).

[0029] 2, the housing 12a includes a storage section 12b and a cover section 12c attached to the storage section 12b. Four laser beam emission openings 12d (see FIG. 4) are arranged in the cover section 12c in a row corresponding to the four photosensitive drums 11a to 11d. Each emission opening 12d has a rectangular shape that is long in the main scanning direction (X direction) of the corresponding laser beam, and the emission openings 12d are formed so that their longitudinal directions (X direction) are parallel to each other.

[0030] The transparent members 52 are formed in the shape of rectangular plates and seal each of the emission openings 12d. This prevents toner, dust, and the like from entering the interior of the optical scanning device 12 through each of the emission openings 12d. The four transparent members 52 are arranged side by side so that their longitudinal directions (X direction) are parallel to each other. Each transparent member 52 is, for example, a glass cover.

[0031] As shown in Figures 3 and 4, two first guide rails 61 are arranged on either side of the pair of permeable members 52, and one more is arranged between the pair of permeable members 52. That is, three first guide rails 61 are arranged side by side on each of the cleaning holders 511 and 512, for a total of six first guide rails 61. The first guide rails 61 protrude from the upper surface of the cover portion 12c and extend in the extension direction (X direction) of the permeable members 52. The first guide rails 61 have a guide rib 61a protruding horizontally from their tip ends (see Figure 5).

[0032] 6 and 7, stoppers 62 are integrally formed on one end (X1 side) of two first guide rails 61 at both ends in the parallel direction (Y direction) of the three first guide rails 61 straddled by the cleaning holders 511, 512. The stoppers 62 restrict movement of the cleaning holders 511, 512 to one side (X1 side) in the extension direction.

[0033] Two second guide rails 63a, 63b are arranged between each of the three first guide rails 61, for a total of four. The second guide rails 63a, 63b protrude from the upper surface of the cover portion 12c and extend in the extension direction (X direction) of the transparent member 52. As shown in Fig. 3, the second guide rail 63a is formed on the outside of the linear member 54 that is stretched in an annular shape. The second guide rail 63b is formed on the inside of the linear member 54 that is stretched in an annular shape.

[0034] 5, the cleaning holders 511 and 512 are disposed on the upper surface of the cover portion 12c (the surface facing the photosensitive drums 11a to 11d). The cleaning holders 511 and 512 each have a main body portion 51a, a first restricting portion 51b, a recessed portion 51d, and a second restricting portion 51d. The main body portion 51a is formed in the shape of a long, narrow plate extending in the parallel direction (Y direction) of the transparent members 52, and is disposed so as to straddle the space between two adjacent transparent members 52.

[0035] The cleaning members 53 are fixed to the lower surface of the main body 51a. A pair of cleaning members 53 are arranged at positions facing the transparent members 52 in the parallel direction (Y direction). As the linear members 54 travel in an annular motion, each cleaning member 53 slides in the X direction along the upper surface of each transparent member 52 (the surface facing the photosensitive drums 11a to 11d). As a result, the upper surfaces of each transparent member 52 are simultaneously cleaned by the corresponding cleaning members 53.

[0036] The cleaning members 53 are, for example, rubber pads. The material of the rubber pads can be, for example, silicone rubber. Each of the cleaning holders 511, 512 is formed from, for example, resin. Note that each of the cleaning members 53 is not limited to rubber pads and may be, for example, nonwoven fabric.

[0037] The first restricting portions 51b are formed on the underside of the main body portion 51a at three locations corresponding to the three first guide rails 61. The first restricting portions 51b protrude downward from the underside of the main body portion 51a, with their tips bent toward the corresponding first guide rails 61. The first restricting portions 51b engage with guide ribs 61a of the corresponding first guide rails 61.

[0038] As a result, both ends of the main body 51a are locked to the first guide rails 61 in the direction away from the housing 12a of the optical scanning device 12 (upward in FIG. 5). The upward movement (positional deviation) of the cleaning holders 511, 512 is restricted, preventing them from detaching from the cover 12c. Therefore, the cleaning members 53 can be stably attached to each transparent member 52.

[0039] Furthermore, in this embodiment, three first guide rails 61 are provided facing both longitudinal ends and near the center of the main body 51a of the cleaning holders 511, 512, and first restricting portions 51b are provided at three locations, both ends and near the center, of the main body 51a, to engage with the guide ribs 61a of the three first guide rails 61. This configuration can prevent the main body 51a near the center where the linear member 54 is fixed from lifting up, thereby further improving the adhesion of the cleaning member 53 to the permeable member 52.

[0040] The second restricting portions 51c are formed on the underside of the main body 51a at two locations corresponding to the two second guide rails 63a, 63b. The second restricting portions 51c contact the side surfaces of the two second guide rails 63a, 63b from the outside in the parallel direction (Y direction) or face each other across a predetermined gap. This restricts horizontal rotation of the main body 51a. As a result, the cleaning holders 511, 512 can maintain an orientation perpendicular to the X direction and can stably move back and forth on each transparent member 52 along the extension direction (X direction).

[0041] The main body 51a has a recess 51d recessed downward from the top surface. A linear member 54 is fixed in the recess 51d. The recess 51d may be formed by recessing upward from the bottom surface of the main body 51a.

[0042] The cleaning holders 511 and 512 each have a first light-shielding portion 511a and a second light-shielding portion 512a. The first light-shielding portion 511a is disposed at a side end of the cleaning holder 511 on one side (Y1 side) in the parallel arrangement direction of the main body 51a and protrudes toward one side (X1 direction) in the extension direction. The second light-shielding portion 512a is disposed at a side end of the cleaning holder 512 on the other side (Y2 side) in the parallel arrangement direction of the main body 51a and protrudes toward one side (X1 direction) in the extension direction (see FIGS. 8 and 9). The first light-shielding portion 511a and the second light-shielding portion 512a have different shapes. For example, the first light-shielding portion 511a does not have a through-hole, and the second light-shielding portion 512a has a through-hole.

[0043] The linear member 54 may be, for example, a timing belt or a wire. The linear member 54 passes between two transparent members 52 in the housing 12a and is stretched in a ring shape between four pulleys 57. The linear member 54 extends between two adjacent transparent members 52 in a direction parallel to the extension direction (X direction) of each transparent member 52. The four pulleys 57 are rotatably held on the upper surface of the cover portion 12c.

[0044] One of the pulleys 57 is connected to a gear 57a disposed on the underside of the cover portion 12c (see FIGS. 8 and 9). The gear 57a is connected to a motor 55. The motor 55 rotates the gear 57a, causing the linear member 54 to travel in a circular motion.

[0045] The motor (drive unit) 55 is disposed outside the linear member 54 and is fixed to the lower surface of the cover portion 12c. That is, the upper end of the motor 55 is disposed below the upper end of the linear member 54. This saves space on the upper surface of the cover portion 12c. Furthermore, by disposing the motor 55 outside the linear member 54, maintenance of the motor 55 and the gear 57a is facilitated. The motor 55 is rotatable forward and backward. When driven by the motor 55, the linear member 54 moves circularly in a clockwise direction (direction D2) or counterclockwise direction (direction D1) in a top view (see FIGS. 8 and 9). This causes the cleaning holders 511 and 512 to reciprocate along the longitudinal direction of the transparent member 52 (the main scanning direction of the laser light). During this reciprocating movement, the cleaning holders 511 and 512 move linearly in opposite directions.

[0046] The cleaning process is executed when the image forming apparatus 1 is in the maintenance mode and the user inputs a process start command from the operation unit 80 (see FIG. 10) or a higher-level device such as a personal computer. The cleaning process may also be executed periodically, for example, every time approximately 10,000 sheets of printing (image formation) are performed.

[0047] The detection unit 56 is disposed on one side (X1 side) in the extension direction of the permeable member 52, and is disposed between the movement path of the cleaning holder 511 and the movement path of the cleaning holder 512 in the parallel direction (Y direction) of the permeable member 52 (see FIGS. 8 and 9). The detection unit 56 detects that one of the cleaning holders 511, 512 has reached one end of the movement path of the cleaning holders 511, 512. When the cleaning holders 511, 512 have reached one end of the movement path, they come into contact with a stopper 62, and their movement to one side (X1 side) in the extension direction is restricted.

[0048] The detection unit 56 is a transmissive optical sensor (photointerrupter) having a light-emitting unit 56a and a light-receiving unit 56b, and one sensor can detect that either the cleaning holder 511 or the cleaning holder 512 has reached one end of the movement path. The light-emitting unit 56a emits light in the parallel direction (Y direction) of the transparent member 52. The light-receiving unit 56b receives the light emitted from the light-emitting unit 56a. Note that, although the light-emitting unit 56a is arranged on one side (Y1 side) of the light-receiving unit 56b in the parallel direction in this embodiment, the light-emitting unit 56a may also be arranged on the other side (Y2 side) of the light-receiving unit 56b in the parallel direction.

[0049] The first light-shielding portion 511a of the cleaning holder 511 and the second light-shielding portion 512a of the cleaning holder 512 have different shapes. This allows the detection unit 56 to detect whether the cleaning holder 511 or the cleaning holder 512 has reached one end of the movement path based on the light-receiving pattern received by the light-receiving unit 56b. Therefore, the detection unit 56 can be simplified, and the manufacturing cost of the optical scanning device 12 can be reduced.

[0050] Next, the operation of the cleaning holder 51 will be described with reference to Figures 8 and 9. In this embodiment, as described above, in one cleaning process, the corresponding cleaning member 53 reciprocates once along the extension direction (X direction) of each permeable member 52. Here, a case will be described in which the running direction of the linear member 54 changes from the direction of arrow D1 to the direction of arrow D2 during the cleaning process.

[0051] At the start of the cleaning process, the cleaning holder 511 turns on the detection unit 56 at one end of its movement path (see FIG. 8). By setting the state in which the cleaning holder 511 is positioned at one end of its movement path as the initial position at the start of the cleaning mode, the detection unit 56 can detect the cleaning holder 511 in the on state. This makes it possible to prevent an initial error from occurring during the cleaning process.

[0052] When the cleaning process starts, the linear member 54 travels in the direction of arrow D1 (see FIG. 8). As a result, the cleaning holder 511 and the cleaning holder 512 move from the position shown in FIG. 8 to the position shown in FIG. 9, and the detection unit 56 detects that the cleaning holder 512 has reached one end of the movement path, causing the linear member 54 to stop traveling. As a result, the cleaning holder 511 and the cleaning holder 512 stop.

[0053] Next, the rotation direction of motor 55 is reversed, and linear member 54 travels in the direction of arrow D2 (see FIG. 9). As a result, cleaning holder 511 and cleaning holder 512 move from the position shown in FIG. 9 to the position shown in FIG. 8, and detection unit 56 detects that cleaning holder 511 has reached one end of the movement path, stopping the travel of linear member 54. As a result, the movement of cleaning holder 511 and cleaning holder 512 stops.

[0054] 10 is a block diagram showing an example of a control path used in the image forming apparatus 1. Note that, since various controls are performed on each section of the image forming apparatus 1 when the image forming apparatus 1 is used, the control path for the entire image forming apparatus 1 becomes complex. Therefore, the following description will focus on the parts of the control path that are necessary for implementing the present invention.

[0055] The voltage control circuit 71 is connected to a motor drive power supply 73, and operates the motor drive power supply 73 in response to an output signal from the control unit 90. The motor drive power supply 73 applies a predetermined drive voltage to the motor 55 in the optical scanning device 12 in response to a control signal from the voltage control circuit 71.

[0056] The operation unit 80 is provided with a liquid crystal display unit 81 and an LED 82 that indicates various states, and is configured to show the state of the image forming apparatus 1, the image formation status, and the number of copies to be printed. Various settings for the image forming apparatus 1 are made using the printer driver of the personal computer.

[0057] The control unit 90 includes at least a CPU (Central Processing Unit) 91 as a central processing unit, a ROM (Read Only Memory) 92 as a read-only memory unit, a RAM (Random Access Memory) 93 as a readable and writable memory unit, a timer 95, and an I / F (Interface) 96 that sends control signals to each device within the image forming apparatus 1 and receives input signals from the operation unit 70.

[0058] The ROM 92 stores data that will not be changed while the image forming apparatus 1 is in use, such as control programs for the image forming apparatus 1 and numerical values ​​necessary for control. The RAM 93 stores necessary data that is generated during the control of the image forming apparatus 1 and data that is temporarily necessary for the control of the image forming apparatus 1. The RAM 93 (or ROM 92) also stores the voltage value (DUTY) applied to the motor 55 in each operation mode of the cleaning holder 51, which will be described later, and the driving time of the motor 55, when cleaning the transparent member 52 of the optical scanning device 12. The timer 95 measures the driving time of the motor 55.

[0059] According to this embodiment, when the detection unit 56 detects that one of the cleaning holders 512 has reached one end of the movement path while the cleaning mode is being executed, the outgoing movement begins, and when the detection unit 56 detects that the other of the cleaning holders 511 has reached one end of the movement path, the returning movement begins. In other words, the control unit 90 determines whether to switch between the returning movement and the outgoing movement based on the detection result of the detection unit 56, thereby reducing the load on the linear member 54 and preventing damage to the pulley 57.

[0060] Furthermore, by setting the state in which the cleaning holder 511 is positioned at one end of the movement path as the initial position when the cleaning mode starts, the detection unit 56 can detect the cleaning holder 511 in the on state. This makes it possible to prevent the occurrence of an initial error in the cleaning process.

[0061] Furthermore, when the cleaning mode starts, the control unit 90 determines whether cleaning holder 511 or cleaning holder 512 is located at one end of the movement path using the detection unit 56, and decides whether to start forward movement or backward movement. This allows the cleaning operation to start quickly regardless of whether cleaning holder 511 or cleaning holder 512 was located at one end of the movement path when the previous cleaning mode ended.

[0062] In this embodiment, the reciprocating movement of the cleaning holders 511, 512 is performed based on the position detection of the cleaning holders 511, 512 by switching the detection unit 56 between on and off, and the cleaning holders 511, 512 are stopped and the direction of movement is reversed before they come into contact with the stopper 62. Instead of the configuration of this embodiment, a method can be used in which the drive time of the motor 55 is measured and the positions of the cleaning holders 511, 512 are estimated from the measured drive time to control the reciprocating movement, or a method can be used in which an increase in the current (voltage) flowing through the motor 55 detects that the cleaning holders 511, 512 have come into contact with the stopper 62 and controls the reciprocating movement.

[0063] 11 is a partial plan view of one end (X2 side) of the optical scanning device 12 of this embodiment as viewed from above. As shown in FIG. 11, the other side (X2 side) in the extension direction of the first guide rail 61 is open in the extension direction (X direction) of the first guide rail 61. More specifically, a rib 12e is provided on the periphery of the cover portion 12c. The first guide rail 61 and the rib 12e are not connected, and a cutout portion 65 is provided between the rib 12e and the end of the first guide rail 61.

[0064] As a result, by disengaging the first restricting portion 51b from the guide rib 61a via the cutout portion 65, the cleaning holders 511, 512 can be easily removed from the first guide rail 61. Furthermore, by sliding the cleaning holders 511, 512 to one side (X1 side) in the extension direction of the first guide rail 61 while engaging the first restricting portion 51b with the guide rib 61a via the cutout portion 65, the cleaning holders 511, 512 can be easily assembled into the first guide rail 61. This improves the ease of attaching and detaching the cleaning holders 511, 512 to and from the optical scanning device 12.

[0065] In this embodiment, the cleaning holders 511, 512 have second restricting portions 51c that contact the side surfaces of the second guide rails 63a, 63b formed on the cover portion 12c. The contact between the second guide rails 63a, 63b and the second restricting portions 51c restricts the rotation of the cleaning holders 511, 512, so the cleaning holders 511, 512 are held vertically without tilting relative to the direction of movement. Therefore, when the cleaning holders 511, 512 start moving in the first direction from a state where they are stopped at the end on the X2 side, it is possible to prevent the cleaning holders 511, 512 from getting caught on the notched portions 65 of the first guide rails 61, thereby preventing malfunctions.

[0066] 11, the second guide rails 63a and 63b are formed to extend toward the other side (X2 side) compared to the first guide rail 61. More specifically, the second guide rails 63a and 63b are formed to overlap the cutout portion 65 when viewed from the parallel direction (Y direction).

[0067] Figures 12 and 13 are partial plan views of the X2 side end of the optical scanning device 12 of this embodiment viewed from above, and respectively show the state in which the cleaning holder 511 is stopped at the X2 side end of the first guide rail 61 and the state in which it has started to move toward the X1 side of the first guide rail 61.

[0068] 12, when the cleaning holder 511 is stopped at the end of the first guide rail 61 on the X2 side, part of the cleaning holder 511 overlaps the notched portion 65. In this state, the guide rib 61a of the first guide rail 61 and the first restricting portion 51b (see FIG. 5) of the cleaning holder 511 remain engaged. Therefore, there is no risk of the cleaning holder 511 coming off the first guide rail 61.

[0069] 12 in the opposite direction (X1 direction), a rotational moment in the pulling direction acts on the cleaning holder 511, which may cause the cleaning holder 511 to tilt. In this case, if an attempt is made to move the cleaning holder 511 in a tilted state, the cleaning holder 511 may get caught on the end (cutout portion 65) of the first guide rail 61, which could result in malfunction.

[0070] In this embodiment, the second guide rails 63a, 63b are formed to extend further in the X2 direction than the first guide rail 61 so as to overlap the cutout portion 65. Therefore, even in the state of FIG. 12 where the cleaning holder 511 is stopped at the X2-side end of the first guide rail 61, the second guide rails 63a, 63b and the second restricting portion 51c are reliably maintained facing each other when viewed from a direction perpendicular to the movement direction (X direction). This allows the cleaning holder 511 to be held vertically without tilting relative to the movement direction (X direction).

[0071] Therefore, when the cleaning holder 511 starts to move toward the X1 side as shown in Figure 13, it is possible to effectively prevent the cleaning holder 511 from getting caught on the end (cutout portion 65) of the first guide rail 61, thereby preventing malfunctions from occurring.

[0072] As long as the second guide rails 63a, 63b are extended further in the X2 direction than the first guide rail 61 (as long as the second guide rail 63 overlaps the recessed portion 65), a predetermined effect can be expected. However, when the cleaning holder 511 completes its movement in the X2 direction and stops, the second guide rails 63a, 63b and the second restricting portion 51c must be in contact. In this way, when the cleaning holder 511 starts to move toward the X1 side, the contact between the second guide rails 63a, 63b and the second restricting portion 51c can reliably hold the cleaning holder 511 in an orientation perpendicular to the movement direction (X direction).

[0073] Here, the traveling direction of the linear member 54 is changed from the X2 direction to the Y1 direction by the pulley 57. Therefore, the tension of the linear member 54 acts to move the outer side (left side in FIG. 12) of the cleaning holder 511 in the movement direction (X2 direction) more than the inner side (right side in FIG. 12). As a result, the cleaning holder 511 is more likely to tilt in the counterclockwise direction in FIG. 12.

[0074] Therefore, in this embodiment, the second guide rail 63a arranged on the outer side of the linear member 54 is formed to extend further in the X2 direction than the second guide rail 63b arranged on the inner side of the linear member 54. Specifically, the second guide rail 63a extends to the rib 12e. This more effectively prevents the cleaning holder 511 from tilting due to the tension of the linear member 54. Note that, because it is necessary to secure a space between the second guide rail 63b and the rib 12e for the linear member 54 to pass through, the second guide rail 63b is formed at a predetermined distance from the rib 12e.

[0075] While the length of the second guide rails 63a, 63b with which the cleaning holder 511 comes into contact has been described above, the same explanation can be applied to the second guide rails 63a, 63b with which the cleaning holder 512 comes into contact. As shown in Figure 8, when the cleaning holder 512 stops at the end on the X2 side, the tension of the linear member 54 acts to move the outer side (right side in Figure 8) of the cleaning holder 512 in the movement direction (X2 direction) more than the inner side (left side in Figure 8). As a result, the cleaning holder 511 is more likely to tilt clockwise in Figure 8.

[0076] Therefore, as shown in Figure 11, by forming the second guide rail 63a (the right end in Figure 11) arranged on the outside of the linear member 54 to extend further in the X2 direction than the second guide rail 63b (the second from the right in Figure 11) arranged on the inside of the linear member 54, the inclination of the cleaning holder 512 can be more effectively suppressed.

[0077] Fig. 14 is a schematic diagram showing a configuration in which the second restricting portion 51c of the cleaning holder 511 abuts against the outer side of the second guide rail 63. In this embodiment, as shown in Fig. 14, the second restricting portion 51c of the cleaning holder 511 abuts against the outer side surface 63c of the second guide rails 63a, 63b in the direction (Y direction) perpendicular to the movement direction of the cleaning holder 511.

[0078] Figure 15 is a diagram showing a state in which a clockwise rotation moment is generated around point P1 when the cleaning device holder 511 is moved in the X2 direction in the configuration of Figure 14. For example, consider a case in which resistance increases on one side in the longitudinal direction (the left side in Figure 15) when the cleaning device holder 511 is moved in the X2 direction. In this case, a clockwise rotation moment is generated around point P1, where the left second guide rail 63a and the second restriction portion 51c come into contact on the upstream side (X1 side) in the movement direction.

[0079] Figure 16 shows a state in which a counterclockwise rotation moment is generated around point P2 when the cleaning holder 511 is further moved in the X2 direction from the state in Figure 15. When the cleaning holder 511 is moved in the X2 direction from the state in Figure 15, resistance increases on the other side in the longitudinal direction (the right side in Figure 16). As a result, a counterclockwise rotation moment is generated around point P2, where the right second guide rail 63b and the second restriction part 51c come into contact, on the downstream side in the movement direction (the X2 side).

[0080] The counterclockwise rotation moment around point P2 acts in a direction that releases the contact between the left second guide rail 63a and the second restriction part 51c at point P1. Therefore, even if the balance of left and right resistance is lost when moving the cleaning holder 511 in the X2 direction, the cleaning holder 511 is less likely to get caught due to its tilt.

[0081] Fig. 17 is a schematic diagram showing a configuration in which the second restricting portion 51c of the cleaning holder 511 abuts against the inner side surface 63d of the second guide rails 63a, 63b. Fig. 18 is a diagram showing a state in which a clockwise rotation moment is generated about point P3 when the cleaning holder 511 is moved in the X2 direction in the configuration of Fig. 17.

[0082] As shown in Figure 17, when the second regulating portion 51c of the cleaning holder 511 abuts against the inner side surface 63d of the second guide rails 63a, 63b in a direction (Y direction) perpendicular to the movement direction of the cleaning holder 511, consider the case where, for example, resistance becomes large on one side in the longitudinal direction (the left side in Figure 18) when moving the cleaning holder 511 in the X2 direction.

[0083] In this case, as shown in FIG. 18, a clockwise rotation moment is generated around point P3 where the left second guide rail 63a and the second restriction portion 51c contact each other on the downstream side (X2 side) in the movement direction.

[0084] Figure 19 shows a state in which a counterclockwise rotation moment is generated around point P4 when the cleaning holder 511 is further moved in the X2 direction from the state in Figure 18. When the cleaning holder 511 is moved in the X2 direction from the state in Figure 18, resistance increases on the other side in the longitudinal direction (the right side in Figure 19). As a result, a counterclockwise rotation moment is generated around point P4, where the right second guide rail 63b and the second restriction part 51c come into contact, on the upstream side in the movement direction (the X1 side).

[0085] The counterclockwise rotational moment around point P4 does not act in a direction that releases the contact between the left-side second guide rail 63 and the second regulating portion 51c at point P3, but acts in a direction that strengthens the contact between the second guide rail 63 and the second regulating portion 51c.

[0086] That is, in a configuration in which the second restricting portion 51c of the cleaning holder 511 abuts against the inner side surface 63d of the second guide rails 63a, 63b, if the balance of left and right resistance when moving the cleaning holder 511 is equal and if the sliding friction resistance of the cleaning holder 511 is small, there is no problem with moving the cleaning holder 511. However, if the balance of left and right resistance when moving the cleaning holder 511 is lost or if the sliding friction resistance of the cleaning holder 511 is large, the cleaning holder 511 is likely to get caught due to its tilt.

[0087] As described above, it is preferable that the second restricting portion 51c of the cleaning device holder 511 is configured to abut against the outer side surface 63c of the second guide rails 63a, 63b in the direction (Y direction) perpendicular to the movement direction of the cleaning device holder 511. Note that although the operation of the cleaning device holder 511 has been described here, the same applies to the cleaning device holder 512.

[0088] 20 and 21 are enlarged partial views of the periphery of the cleaning member 53 on one side (left side) and the other side (right side) of the cleaning holder 511 in Fig. 5. In this embodiment, the transparent member 52 is fixed to the cover portion 12c by adhesively fixing the end face of the transparent member 52 in the short direction (X direction) perpendicular to the longitudinal direction (direction perpendicular to the paper surface of Fig. 20) with an adhesive 70 such as ultraviolet curing resin.

[0089] 20 and 21, the solidified adhesive 70 is disposed vertically on the end surface of the permeable member 52. If the second restricting portion 51c of the cleaning holder 511 extends below the upper surface of the permeable member 52, the cleaning holder 511 may come into contact with the adhesive 70 when it moves.

[0090] If the adhesive 70 is applied discretely along the longitudinal direction of the permeable member 52 in order to reduce the amount of adhesive used, the second restricting portion 51c may get caught on the adhesive 70, causing malfunction of the cleaning holder 511. For this reason, in this embodiment, the second restricting portion 51c of the cleaning holder 511 is provided above the upper surface of the permeable member 52. This makes it possible to avoid contact between the second restricting portion 51c and the adhesive 70 when the cleaning holder 511 moves, thereby suppressing malfunction of the cleaning holder 511.

[0091] 22 is a partial plan view of the X2-side end of the optical scanning device 12 of this embodiment seen from above, illustrating a state in which the cleaning holders 511, 512 are stopped at the X2-side end of the first guide rail 61. In FIG. 22, the pulley 57 is attached to the open side (the cutout portion 65 side) of the first guide rail 61, and movement of the cleaning holders 511, 512 in the X2 direction is restricted by the pulley 57. In the state of FIG. 22, the first restriction portion 51b of the cleaning holders 511, 512 is positioned to engage with the guide rib 61a of the first guide rail 61, and the cleaning holders 511, 512 cannot be removed from the cover portion 12c.

[0092] Figure 23 shows the state in which the cleaning holders 511, 512 have been moved in the X2 direction with the pulley 57 removed. In the state in Figure 23, the removal of the pulley 57 allows the cleaning holders 511, 512 to move in the X2 direction. The engagement between the first restriction portions 51b of the cleaning holders 511, 512 and the guide rib 61a of the first guide rail 61 is released, and the cleaning holders 511, 512 can be attached and detached via the cutout portions 65.

[0093] In this embodiment, one end of the first guide rail 61 is open (a cutout 65 is provided) to facilitate attachment and detachment of the cleaning holders 511 and 512. However, from the viewpoint of ensuring the operation of the optical scanning device 12, it is not preferable for users to be able to easily attach and detach the cleaning holders 511 and 512.

[0094] For this reason, the cleaning holders 511, 512 cannot be attached or detached unless the pulley 57 on the open side (the cutout 65 side) of the first guide rail 61 is removed. In other words, the pulley 57 functions as a restricting member that restricts the attachment or detachment of the cleaning holders 511, 512. This eliminates the risk of the cleaning holders 511, 512 being inadvertently removed.

[0095] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the present invention. For example, in the above-described embodiment, three first guide rails 61 and two second guide rails 63a, 63b are provided for each cleaning holder 511, 512. However, it is acceptable as long as a plurality of first guide rails 61 and a plurality of second guide rails 63a, 63b are provided for each cleaning holder 511, 512.

[0096] Furthermore, in the above embodiment, an optical scanning device 12 was described that has a pair of cleaning holders 511, 512 that move back and forth in opposite directions as the linear member 54 moves, but the present invention can also be applied in exactly the same way to an optical scanning device 12 that has only one cleaning holder.

[0097] Furthermore, in the above embodiment, a tandem color printer has been used as an example of the image forming apparatus 1 equipped with the optical scanning device 12, but the present invention is not limited to color printers and can be applied to electrophotographic image forming apparatuses equipped with the optical scanning device 12, such as color copiers, monochrome printers, monochrome copiers, digital multifunction machines, and facsimiles. [Industrial Applicability]

[0098] The present invention can be used in an optical scanning device that irradiates an image carrier with light to form an electrostatic latent image. By using the present invention, it is possible to provide an optical scanning device that can suppress malfunction of a cleaning holder that cleans a transparent member and improve the ease of attaching and detaching the cleaning holder, and an image forming apparatus equipped with the same. [Explanation of symbols]

[0099] 1. Image forming device 12 Optical scanning device 12a housing 12b Storage section 12c Cover 12d exit port 12e Rib 511, 512 Cleaning holder 51a Main body 51b 1st Regulatory Division 51c Second Regulatory Section 51d Recess 511a 1st light shielding part 512b 2nd light shielding part 52 Permeable member 53 Cleaning materials 54 Linear members 55 Motor (drive unit) 56 Detection unit 57 Pulley 61 First guide rail 61a Guide rib 62 Stopper 63a, 63b Second guide rail 65 Missing part 70 Adhesive 120 Scanning Optical System Pa~Pd Image forming section

Claims

1. An optical scanning device that forms an electrostatic latent image by irradiating an image carrier with laser light, a housing in which an exit port for the laser light extending in the main scanning direction of the laser light is formed corresponding to the image carrier; a transparent member that is transparent to the laser light, extends in the main scanning direction of the laser light, and seals an exit port of the laser light; a linear member stretched in a ring shape on the housing; a drive unit that causes the linear member to travel in a predetermined direction; a plurality of first guide rails formed on an upper surface of the housing and extending in an extension direction of the transparent member; a plurality of second guide rails formed on the upper surface of the housing and extending parallel to the first guide rails; one or more cleaning holders fixed to the linear member, and moving on the transparent member along the first guide rail and the second guide rail in a first direction and a second direction opposite to the first direction when the linear member is moved by the driving unit; a cleaning member fixed to the cleaning holder and configured to clean the permeable member by sliding relative to the permeable member as the cleaning holder moves; a stopper formed at an end of the first guide rail on the first direction side, the stopper restricting movement of the cleaning holder in the first direction; Equipped with The housing includes: a rib formed along the periphery of the top surface of the housing; a cutout portion formed between the end of the first guide rail on the second direction side and the rib, the cutout portion being capable of releasing the engagement between the first guide rail and the first restricting portion; and The cleaning holder is a first restricting portion that vertically engages with the first guide rail to restrict upward movement of the cleaning holder; a second restricting portion that contacts a side surface of the second guide rail to restrict rotation of the cleaning holder; An optical scanning device comprising:

2. the second guide rail is formed to extend in the second direction further than the first guide rail when viewed in a direction perpendicular to the moving direction of the cleaning holder, The optical scanning device according to claim 1, characterized in that when the cleaning holder completes its movement in the second direction and stops, the second guide rail and the second regulating portion face each other when viewed from a direction perpendicular to the movement direction.

3. the linear member is fixed to a substantially central portion of the cleaning holder in a longitudinal direction perpendicular to the moving direction, The second guide rail is formed at two locations, one on the inside and one on the outside of the linear member stretched in an annular shape, The optical scanning device according to claim 2, characterized in that the second guide rail formed on the outer side of the linear member is formed to extend in the second direction further than the second guide rail formed on the inner side of the linear member.

4. 2. The optical scanning device according to claim 1, wherein when the first guide rail and the first regulating portion are engaged, the tip of the second regulating portion is positioned above the upper surface of the transparent member.

5. The second guide rails are arranged in pairs at a predetermined interval in the longitudinal direction of the cleaning holder, The optical scanning device according to claim 1 , wherein the second restricting portion contacts an outer side surface of the second guide rail in the longitudinal direction.

6. a pulley around which the linear member is wound is detachably attached to an upper surface of the housing near an end of the first guide rail on the second direction side; When the pulley is attached to the housing, the cleaning holder is restricted from moving to a position where it overlaps with the cutout portion, The optical scanning device of claim 1, characterized in that the engagement between the first guide rail and the first regulating portion can be released by removing the pulley from the housing and moving the cleaning holder to a position overlapping the missing portion.

7. The cleaning member is fixed to the cleaning holder at two positions in the longitudinal direction, 2. The optical scanning device according to claim 1, wherein the first guide rail and the first restricting portion are arranged at three positions on either side of the cleaning member in the longitudinal direction.

8. The linear member is fixed to the cleaning holder at a substantially central portion in the longitudinal direction, 8. The optical scanning device according to claim 7, wherein the first guide rail and the first restricting portion are disposed at three locations: at both ends in the longitudinal direction and in the vicinity of the linear member.

9. an image forming unit including one or more of the image carriers; an optical scanning device according to any one of claims 1 to 8, wherein an electrostatic latent image is formed by irradiating the image carrier with a laser beam; An image forming apparatus comprising:

Images