Exposure device and image forming device

The exposure apparatus addresses positional deviations in image forming devices by using a rotatable support member and adjusted friction coefficients, ensuring precise and compact image formation.

JP7760862B2Active Publication Date: 2025-10-28FUJIFILM BUSINESS INNOVATION CORP
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Patent Information

Application Number
JP2021137616
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2021-08-25
Publication Date
2025-10-28
Estimated Expiration
2041-08-25

AI Technical Summary

Technical Problem

Existing exposure devices and image forming apparatuses suffer from positional deviation in directions perpendicular to the light irradiation direction due to configurations where a contact member is fixed to a support member.

Method used

The exposure apparatus incorporates a light-emitting unit with a base, a contact member, a support member that is rotatably supported, and a position adjustment unit with a moving member that adjusts the support member in the light irradiation direction, featuring a coefficient of friction design and structural arrangements to minimize perpendicular positional deviations.

Benefits of technology

This configuration suppresses positional deviation, reduces friction, and allows for a more compact and precise image formation by minimizing tilting and twisting of components, thereby enhancing the overall image quality in wide-format image forming devices.

✦ Generated by Eureka AI based on patent content.

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Abstract

To provide an exposure device that can suppress misalignment in a direction perpendicular to the light emission direction of a light emitter, compared to a structure where a contact member is fixed to a support member.SOLUTION: An exposure device includes a light emitter that includes a substrate and a light-emitting device disposed on the substrate, and a position adjuster that includes a contact member having its outer periphery in contact with the substrate, a support member that rotatably supports the contact member, and a mover that is in contact with the support member to move the support member in a light emission direction of the light emitter.SELECTED DRAWING: Figure 10
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Description

[Technical Field]

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

[0002] Patent Document 1 listed below discloses a focus adjustment device for an optical writing device that aligns the focal position of light irradiated from a plurality of light-emitting elements arranged in a row corresponding to each pixel in the main scanning direction in an image formation area with the surface of an image carrier, the focus adjustment device comprising: a storage means for storing a pattern image; an image forming means for forming an electrostatic latent image pattern on the surface of the image carrier corresponding to the pattern image stored in the storage means; a surface potential measuring means for measuring the surface potential of the electrostatic latent image pattern area on the surface of the image carrier formed by the image forming means; and a displacement mechanism for displacing the position of the optical writing device relative to the surface of the image carrier based on the surface potential measured by the surface potential measuring means so that the focal point of the light from the light-emitting elements aligns with the surface of the image carrier.

[0003] The following Patent Document 2 discloses an image forming apparatus comprising an image carrier, an LED print head arranged close to the surface of the image carrier and exposing image information to the image carrier by irradiating light, a first positioning means fixed to the image forming apparatus main body and supporting the image carrier, and a second positioning means arranged on the LED print head and abutting against the first positioning means to regulate the distance between the image carrier and the LED print head, wherein an elastic means is provided between the second positioning means and the LED print head for urging the second positioning means in a predetermined direction away from the LED print head.

[0004] The following Patent Document 3 discloses an optical head positioning device characterized by having a cylindrical photosensitive drum extending in the longitudinal direction, an optical head extending parallel to the photosensitive drum, and at least one spacer arranged to abut against the photosensitive drum and regulating the distance between the optical head and the surface of the photosensitive drum. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-22259 [Patent Document 2] Japanese Patent Application Laid-Open No. 2005-14497 [Patent Document 3] Japanese Patent Application Laid-Open No. 2002-361931 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention aims to provide an exposure device and an image forming device that can suppress positional deviation in a direction perpendicular to the light irradiation direction of the light-emitting section, compared to a configuration in which a contact member is fixed to a support member. [Means for solving the problem]

[0007] The exposure apparatus of the first embodiment includes a light-emitting unit having a base and a light-emitting element arranged on the base, a contact member whose outer periphery is in contact with the base, a support member that rotatably supports the contact member, and a position adjustment unit that includes a moving member that is in contact with the support member and moves the support member in the light irradiation direction of the light-emitting unit.

[0008] The exposure apparatus of a second aspect is the exposure apparatus of the first aspect, wherein the coefficient of friction between the contact member and the substrate is smaller than the coefficient of friction between the support member and the contact member.

[0009] The exposure apparatus of the third aspect is the exposure apparatus of the first or second aspect, wherein the base extends in one direction, the light-emitting elements are arranged in multiple in the one direction, the support member is an axial member, and the position adjustment unit has a receiving portion that receives the axial member rotatably with a direction perpendicular to the one direction as its axial direction and movable in the light irradiation direction.

[0010] The exposure apparatus of the fourth aspect is the exposure apparatus of the third aspect, wherein the movable member is movable in the one direction, and the movable member is provided with a conversion unit that converts the moving force in the one direction into a moving force for moving the shaft member in the light irradiation direction.

[0011] The exposure apparatus of a fifth aspect is the exposure apparatus of the fourth aspect, wherein the conversion part is provided on a part of the moving member that comes into contact with the shaft member, and is an inclined surface that is inclined with respect to the one direction.

[0012] The exposure apparatus of the sixth aspect is the exposure apparatus of the fifth aspect, wherein the movable member has a pair of the inclined surfaces, and the pair of inclined surfaces are in contact with both side portions of the shaft member, sandwiching the contact member therebetween.

[0013] The exposure apparatus of the seventh aspect is an exposure apparatus of any one of the third to sixth aspects, in which the receiving portions are arranged opposite each other in the short side direction of the base, the opposing receiving portions each receive the shaft member, and the contact member is arranged between the opposing receiving portions of the shaft member.

[0014] The exposure apparatus of the eighth aspect is an exposure apparatus of any one of the third to fifth aspects, in which there is one contact member and two movable members arranged in a direction perpendicular to the one direction, and the contact member is arranged between the two movable members.

[0015] An exposure apparatus of a ninth aspect is the exposure apparatus of any one of the first to eighth aspects, wherein the outer diameter of the contact member is larger than the outer diameter of a shaft member that is the support member.

[0016] The exposure apparatus of the 10th aspect is an exposure apparatus of the 3rd aspect or any one of the 4th to 8th aspects that refer to the 3rd aspect, wherein the position adjustment unit has a feed member that moves the movable member in the one direction, and the feed member and the contact member overlap in the light irradiation direction.

[0017] An eleventh aspect of the exposure apparatus is the tenth aspect of the exposure apparatus, wherein the feed member is a screw member that extends in the one direction and moves the moving member in the one direction by rotating around an axis, and the position adjustment unit further has a drive source that rotates the screw member.

[0018] The exposure apparatus of the 12th aspect is an exposure apparatus of the 3rd aspect or any one of the 4th to 11th aspects that refer to the 3rd aspect, wherein a straight line passing through the contact point between the contact member and the base and the contact point between the movable member and the shaft member is along the light irradiation direction.

[0019] An image forming apparatus of a thirteenth aspect includes an image carrier, an exposure device of any one of the first to twelfth aspects that exposes the image carrier to form an electrostatic latent image and is capable of adjusting the distance between the image carrier and a light-emitting element, and a developing device that develops the electrostatic latent image on the image carrier. [Effects of the Invention]

[0020] According to the exposure apparatus of the first aspect, positional deviation in the direction perpendicular to the light emission direction of the light emitting section can be suppressed compared to a configuration in which the contact member is fixed to the support member.

[0021] According to the exposure apparatus of the second aspect, positional deviation in a direction perpendicular to the light emission direction of the light emitting section can be suppressed compared to a configuration in which the coefficient of friction between the contact member and the base is equal to or greater than the coefficient of friction between the support member and the contact member.

[0022] According to the exposure apparatus of the third aspect, the length in one direction can be made shorter compared to when the shaft member extends in one direction.

[0023] According to the exposure apparatus of the fourth aspect, the size of the apparatus in the light irradiation direction can be made more compact than in a configuration in which the movable member moves in the light irradiation direction to move the shaft member in the light irradiation direction.

[0024] According to the exposure apparatus of the fifth aspect, it is possible to reduce friction between the moving member and the shaft member.

[0025] According to the exposure apparatus of the sixth aspect, tilting of the shaft member can be suppressed compared to a configuration in which the sloped surface of the moving member is in contact with only one side of the shaft member, sandwiching the contact member therebetween.

[0026] According to the exposure device of the seventh embodiment, compared to a configuration in which the contact member is arranged outside the opposing receiving portion of the shaft member, it is possible to suppress twisting of the base body that occurs when the contact member adjusts the position of the base body in the light irradiation direction.

[0027] According to the exposure apparatus of the eighth aspect, it is possible to suppress twisting of the substrate that occurs when the position of the substrate in the light irradiation direction is adjusted by the contact member while maintaining the balance between the contact member and the moving member.

[0028] According to the exposure apparatus of the ninth aspect, compared to a configuration in which the outer diameter of the contact member is equal to or smaller than the outer diameter of the shaft member, it is possible to prevent the shaft member from interfering with the base even if the base is wide in the lateral direction.

[0029] According to the exposure apparatus of the tenth aspect, it is possible to reduce loss of the moving force of the moving member that is transmitted to the shaft member, compared to a configuration in which the feed member and the contact member are misaligned in the light irradiation direction.

[0030] According to the exposure apparatus of the eleventh aspect, the amount of movement of the movable member in one direction can be finely adjusted, compared to a configuration in which the movable member is moved in one direction by rotating a belt to which the movable member is attached.

[0031] According to the exposure apparatus of the 12th aspect, positional deviation of the light-emitting unit in a direction perpendicular to the light irradiation direction can be suppressed compared to a configuration in which the straight line passing through the contact point between the contact member and the base and the contact point between the movable member and the shaft member is inclined with respect to the light irradiation direction.

[0032] According to the image forming apparatus of the thirteenth aspect, it is possible to form an image with higher precision than the configuration of any one of the first to twelfth aspects that does not use the exposure device. [Brief explanation of the drawings]

[0033] [Figure 1] 1 is a schematic view showing an image forming apparatus equipped with an exposure device according to a first embodiment. [Figure 2] FIG. 2 is a perspective view showing an exposure device used in the image forming apparatus. [Figure 3] FIG. 2 is a configuration diagram showing the exposure device as viewed from above and below. [Figure 4] FIG. 2 is a perspective view showing a plurality of light irradiation units of the exposure device. [Figure 5] FIG. 2 is an enlarged perspective view of a part of the exposure apparatus. [Figure 6] 2 is a cross-sectional view showing a state in which a plurality of light irradiation units of the exposure device are cut in the short side direction. FIG. [Figure 7] FIG. 2 is a cross-sectional view showing the exposure device cut in the short direction. [Figure 8] FIG. 2 is a perspective view showing a light irradiation unit of the exposure device. [Figure 9] FIG. 2 is a perspective view showing a state in which a part of the light irradiation unit is cut in the short side direction. [Figure 10] FIG. 2 is a side view of a position adjustment unit of the exposure device. [Figure 11] FIG. 2 is a side view, with a portion thereof cut away, of a position adjustment unit of the exposure apparatus. [Figure 12] FIG. 2 is a front view, with a portion of the position adjustment unit of the exposure device in cross section. [Figure 13] FIG. 10 is a side view, with a portion thereof cut away, of a position adjustment unit according to a modified example. [Figure 14] FIG. 10 is a front view, with a portion thereof cut away, of a position adjustment section according to a modified example. [Figure 15] FIG. 10 is a side view, with a portion thereof cut away, of a position adjustment unit according to a modified example. [Figure 16] FIG. 10 is a front view, with a portion thereof cut away, of a position adjustment section according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0034] Hereinafter, an embodiment of the present invention (hereinafter referred to as the present embodiment) will be described.

[0035] [First embodiment] <Image forming apparatus 10> 1 is a schematic diagram showing the configuration of an image forming apparatus 10 equipped with an exposure device 40 according to a first embodiment. First, the configuration of the image forming apparatus 10 will be described. Next, the exposure device 40 used in the image forming apparatus 10 will be described. The image forming apparatus 10 is, as an example, an image forming apparatus that forms images in multiple colors, such as a full-color printer for commercial printing that requires particularly high image quality.

[0036] Furthermore, the image forming apparatus 10 is a wide-width image forming apparatus that supports widths exceeding the width of the recording medium P when B3 is fed vertically (i.e., widths exceeding 364 mm). As an example, it supports recording media P with sizes of 420 mm or more for A2 vertical feeding and 1456 mm or less for B0 horizontal feeding. For example, the image forming apparatus 10 supports 728 mm for B2 horizontal feeding.

[0037] The image forming apparatus 10 shown in FIG. 1 is an example of an image forming apparatus that forms an image on a recording medium. Specifically, the image forming apparatus 10 is an electrophotographic image forming apparatus that forms a toner image (an example of an image) on a recording medium P. Toner is an example of powder. More specifically, the image forming apparatus 10 includes an image forming unit 14 and a fixing device 16. Each unit of the image forming apparatus 10 (the image forming unit 14 and the fixing device 16) will be described below.

[0038] (Image forming unit 14) The image forming unit 14 has a function of forming a toner image on the recording medium P. Specifically, the image forming unit 14 has a toner image forming unit 22 and a transfer device 17.

[0039] <Toner image forming unit 22> 1 is provided so as to form a toner image for each color. In this embodiment, toner image forming units 22 for a total of four colors, yellow (Y), magenta (M), cyan (C), and black (K), are provided. (Y), (M), (C), and (K) shown in FIG. 1 indicate components corresponding to the above colors.

[0040] Since the toner image forming units 22 for each color are configured in the same manner except for the toner used, the respective parts of the toner image forming unit 22(K) are denoted by reference numerals in FIG. 1 as a representative of the toner image forming units 22 for each color.

[0041] Specifically, each toner image forming unit 22 for each color has a photosensitive drum 32 that rotates in one direction (for example, counterclockwise in FIG. 1). Here, the photosensitive drum 32 is an example of an image carrier. Furthermore, each toner image forming unit 22 for each color has a charger 23, an exposure device 40, and a developing device 38.

[0042] In the toner image forming unit 22 for each color, the charger 23 charges the photosensitive drum 32. Furthermore, the exposure device 40 exposes the photosensitive drum 32 charged by the charger 23 to light, thereby forming an electrostatic latent image on the photosensitive drum 32. Furthermore, the developing device 38 develops the electrostatic latent image formed on the photosensitive drum 32 by the exposure device 40, thereby forming a toner image.

[0043] The photosensitive drum 32 rotates while holding the electrostatic latent image formed as described above on its outer periphery, and the electrostatic latent image is transported to the developing device 38. The specific configuration of the exposure device 40 will be described later.

[0044] -Transfer device 17- 1 is a device that transfers the toner image formed in the toner image forming unit 22 onto a recording medium P. Specifically, the transfer device 17 performs primary transfer of the toner image of each color on the photosensitive drum 32 onto a transfer belt 24 serving as an intermediate transfer body, superimposing the toner image, and then performs secondary transfer of the superimposed toner image onto the recording medium P. Specifically, as shown in FIG. 1, the transfer device 17 includes the transfer belt 24, a primary transfer roll 26, and a secondary transfer roll 28.

[0045] The primary transfer roll 26 is a roll that transfers the toner image of each color on the photosensitive drum 32 to the transfer belt 24 at a primary transfer position T1 between the photosensitive drum 32 and the primary transfer roll 26. In this embodiment, a primary transfer electric field is applied between the primary transfer roll 26 and the photosensitive drum 32, so that the toner image formed on the photosensitive drum 32 is transferred to the transfer belt 24 at the primary transfer position T1.

[0046] The toner image is transferred from the photosensitive drum 32 of each color onto the outer peripheral surface of the transfer belt 24. Specifically, the transfer belt 24 is configured as follows: As shown in Fig. 1, the transfer belt 24 is annular and is wound around multiple rolls 39 to determine its position.

[0047] The transfer belt 24 rotates in the direction of arrow A, for example, when a drive roll 39D among the plurality of rolls 39 is rotationally driven by a drive unit (not shown). Of the plurality of rolls 39, a roll 39B shown in FIG. 1 is an opposing roll 39B that faces the secondary transfer roll 28.

[0048] The secondary transfer roll 28 is a roll that transfers the toner image transferred to the transfer belt 24 to the recording medium P at a secondary transfer position T2 between the opposing roll 39B and the secondary transfer roll 28. In this embodiment, a secondary transfer electric field is applied between the opposing roll 39B and the secondary transfer roll 28, so that the toner image transferred to the transfer belt 24 is transferred to the recording medium P at the secondary transfer position T2.

[0049] -Fuser 16- The fixing device 16 shown in Fig. 1 is a device that fixes a toner image transferred to a recording medium P by a secondary transfer roll 28 to the recording medium P. Specifically, as shown in Fig. 1, the fixing device 16 has a heating roll 16A as a heating member and a pressure roll 16B as a pressure member. In the fixing device 16, the toner image formed on the recording medium P is fixed to the recording medium P by heating and pressurizing the recording medium P with the heating roll 16A and the pressure roll 16B.

[0050] <Exposure device 40> Next, the configuration of the exposure apparatus 40, which is a main part of this embodiment, will be described. FIG. 2 is a perspective view showing the configuration of the exposure apparatus 40. FIG. 3 is a plan view showing the exposure apparatus 40 as viewed from above and below. In the following description, the arrow Y direction shown in the figure will be described as the width direction of the exposure apparatus 40, and the arrow Z direction will be described as the height direction of the exposure apparatus 40. Furthermore, the arrow X direction, which is perpendicular to both the apparatus width direction and the apparatus height direction, will be described as the depth direction of the exposure apparatus 40. Note that the width direction and height direction described above are directions defined for the convenience of explanation, and the configuration of the exposure apparatus 40 is not limited to these directions.

[0051] First, the overall configuration of the exposure apparatus 40 will be described, and then each component of the exposure apparatus 40 will be described.

[0052] As shown in FIG. 10, the exposure device 40 includes a light emitting unit 41 and a position adjusting unit 130.

[0053] (Light emitting part 41) As shown in Figures 2 and 3, the light-emitting unit 41 includes a base 42 extending in one direction (the direction of arrow X in this embodiment) and a plurality of light irradiation units 44 provided on one side of the base 42 in the direction of arrow Z (the upper side in the up-down direction in Figures 2 and 3). In this embodiment, three light irradiation units 44 extending in one direction of the base 42 are provided. The base 42 is an elongated member that is rectangular in plan view as shown in Figure 3. The light irradiation units 44 each have the same configuration and are elongated members that are rectangular in plan view as shown in Figure 3.

[0054] As an example, the three light irradiation units 44 are arranged to be offset in one direction (arrow X direction) of the base 42, and are also arranged to be offset in a width direction perpendicular to the one direction of the base 42, i.e., in the short side direction (arrow Y direction) of the base 42. The light emitting unit 41 is arranged along the axial direction of the photosensitive drum 32 (see FIG. 1). The length of the light emitting unit 41 in one direction (arrow X direction) is equal to or greater than the axial length of the photosensitive drum 32. One or more of the three light irradiation units 44 faces the surface (outer peripheral surface) of the photosensitive drum 32. This allows the light emitted from the light emitting unit 41 to be irradiated onto the surface of the photosensitive drum 32.

[0055] 2 and 3, the side of the base 42 on which the light irradiation unit 44 is provided is illustrated as being the upper side in the vertical direction, and light is irradiated from the light irradiation unit 44 toward the upper side, but in the image forming apparatus 10 shown in Fig. 1, the up-down direction of the exposure device 40 is reversed. That is, in Fig. 1, the exposure device 40 is disposed so that the side of the base 42 on which the light irradiation unit 44 is provided is the lower side in the vertical direction, and light is irradiated from the light irradiation unit 44 toward the photosensitive drum 32 below.

[0056] In this embodiment, the three light irradiation units 44 are arranged in a staggered pattern when viewed from the top, bottom, and upper sides of the exposure device 40 (see FIG. 3 ). More specifically, two light irradiation units 44 are arranged on one side of the short-side direction (arrow Y direction) of the base 42 at both end sides in one direction (arrow X direction) of the base 42. One light irradiation unit 44 is arranged on the other side of the short-side direction (arrow Y direction) of the base 42 at the center of the base 42 in one direction (arrow X direction). The ends of the two light irradiation units 44 arranged on one side of the short-side direction (arrow Y direction) of the base 42 and the end of the one light irradiation unit 44 arranged on the other side of the short-side direction (arrow Y direction) of the base 42 overlap with each other when viewed from the short-side direction (arrow Y direction) of the base 42. That is, in one direction (arrow X direction) of the base 42, the irradiation areas of light from the three light irradiation units 44 partially overlap.

[0057] 4 and 5, the exposure device 40 includes a harness 46 electrically connected to each of the three light irradiation units 44, a plurality of brackets 48 for holding the harness 46, and a lower cover 50 for externally covering the harness 46 and the brackets 48. The harness 46 is an assembly of a plurality of wires used for power supply. The brackets 48 are attached to the base 42 and extend from the base 42 to the other side in the direction of arrow Z (the lower side in the vertical direction in FIG. 2). The lower cover 50 is attached to the other side of the base 42 in the direction of arrow Z (the lower side in the vertical direction in FIG. 2).

[0058] 2 and 3, the exposure device 40 is provided with side covers 52 that cover the sides of the three light irradiation units 44. The side covers 52 are plate-shaped, and their lower end sides are attached to both sides in the short direction (direction of arrow Y) of the base 42. The exposure device 40 is also provided with a cleaning device 54 that cleans a lens unit 68 of the light irradiation units 44, which will be described later.

[0059] 5 and 6, the exposure device 40 also includes a plurality of spacers 56 sandwiched between the base 42 and the light irradiation unit 44, and a fastening member 58 that fixes the light irradiation unit 44 to the base 42 with the plurality of spacers 56 interposed therebetween. The fastening member 58 is, for example, a member that has a spiral groove and fastens using this groove. In other words, it is a member that has a screw mechanism, such as a screw, bolt, or screw.

[0060] Although not shown, positioning shafts extending upward in the vertical direction are provided at both ends of the base 42 in one direction (the direction of the arrow X). The positioning shafts are inserted into insertion portions formed in bearing members provided at both ends of the photosensitive drum 32, thereby positioning the light-emitting unit 41 relative to the photosensitive drum 32 in a direction perpendicular to the light irradiation direction. Specifically, the light-emitting unit 41 is positioned in the Y direction relative to the photosensitive drum 32.

[0061] 5 to 8, the base 42 is made up of a rectangular parallelepiped elongated member. The base 42 is disposed in a position facing the entire axial length of the photosensitive drum 32 (FIG. 1).

[0062] A recess 80 into which the spacers 56 are inserted is provided on the surface 42A on the upper side in the vertical direction (arrow Z direction) of the base 42 (see FIG. 6). As an example, three spacers 56 are arranged at intervals in one direction (arrow X direction) for one light irradiation unit 44. In this embodiment, three spacers 56 are arranged for each of the three light irradiation units 44.

[0063] The recess 80 includes an inclined surface 80A that forms the bottom surface and is inclined relative to the surface 42A of the base 42, a vertical wall 80B disposed at the downward end of the inclined surface 80A, and two vertical walls (not shown) disposed opposite each other on both sides of the inclined surface 80A (see FIG. 5). As an example, the inclined surface 80A facing the two light irradiators 44 disposed on one side of the base 42 in the short direction and the inclined surface 80A facing the one light irradiator 44 disposed on the other side of the base 42 in the short direction are inversely inclined. In the light-emitting unit 41, the inclined surface 80A with an inverse inclination is adjusted so that light is irradiated toward the center of the photosensitive drum 32 (see FIG. 1) from the two light irradiators 44 disposed on one side of the base 42 in the short direction and the one light irradiator 44 disposed on the other side of the base 42 in the short direction. When there is one light irradiator 44, the light irradiating direction of the light emitting unit 41 onto the photosensitive drum 32 is the optical axis direction of the light irradiator 44. On the other hand, when there are multiple light irradiators 44 as in this embodiment, the light irradiating direction is the direction from the midpoint in the lateral direction (Y direction) of the base 42 between the principal points of each light irradiator 44 toward the focal point when viewed from one direction (X direction) of the base 42. In this embodiment, the position and angle of each light emitting unit 41 are adjusted so that the light irradiating direction is the direction toward the center of the photosensitive drum 32.

[0064] In this embodiment, the base 42 is made of a metal block. The metal block in this embodiment does not include general sheet metal that is formed into a shape by bending, but refers to a metal block that is thick enough that it cannot be bent into a shape used as the base of the exposure device 40. As an example, the base 42 is a metal block whose thickness is 10% or more of the width of the base 42. Furthermore, the base 42 may be made of a metal block whose thickness is 20% or more and 100% or less of the width of the base 42.

[0065] Conventional wide-format image forming devices are used for outputting black-and-white drawings, which do not require high image quality compared to full-color printers for commercial printing, and use sheet metal as the base. On the other hand, the image forming device 10 of this embodiment is a full-color printer for commercial printing, which requires high image quality. Therefore, to prevent the bending of the base 42 from affecting image quality, a metal block with higher rigidity than sheet metal is used.

[0066] The base 42 is made of, for example, steel or stainless steel. However, the base 42 may be made of a metal block other than steel or stainless steel. For example, aluminum, which has higher thermal conductivity and is lighter than steel or stainless steel, may be used. However, in this embodiment, heat generated by the light source 64 is mainly dissipated by the support 60. Therefore, steel or stainless steel is used for the base 42, as rigidity takes priority over thermal conductivity and weight.

[0067] Furthermore, the thickness of the base 42 in the vertical direction (arrow Z direction) is preferably greater than the thickness of the support 60 that constitutes the light irradiation unit 44. This makes the rigidity (bending rigidity in the arrow Z direction) of the base 42 greater than the rigidity of the light irradiation unit 44. The thickness of the base 42 in the vertical direction (arrow Z direction) is preferably 5 mm or more, more preferably 10 mm or more, and even more preferably 20 mm or more.

[0068] As shown in FIG. 6 , a recessed portion 82 is formed on the back surface 42B of the base 42 opposite the front surface 42A, the recessed portion 82 being cut out toward the spacer 56, i.e., toward the recessed portion 80. The recessed portions 82 are provided at positions corresponding to the recessed portions 80 of the base 42. The recessed portions 82 are formed obliquely from the back surface 42B of the base 42 toward the center of the base 42 in the short direction (Y direction). For example, the recessed portion 82 has a circular shape when viewed from the back surface 42B of the base 42. The inner diameter of the recessed portion 82 is larger than the outer shape of the head 58A of the fastening member 58. A through-hole 84 is provided in the bottom surface 82A of the recessed portion 82, through which the shank 58B of the fastening member 58 penetrates the base 42. The through-hole 84 opens into the inclined surface 80A of the recessed portion 80.

[0069] 2 to 7, the three light irradiation units 44 have the same configuration as described above. As an example, the two light irradiation units 44 on one side in the short side direction (arrow Y direction) of the base 42 and the one light irradiation unit 44 on the other side in the short side direction (arrow Y direction) of the base 42 are arranged symmetrically in the short side direction (arrow Y direction) of the base 42.

[0070] As shown in FIG. 6 , the light irradiation unit 44 includes a support 60 extending in one direction (the direction of the arrow X) and a light-emitting element substrate 62 supported on the surface of the support 60 opposite the base 42 in the vertical direction (the direction of the arrow Z) (in this embodiment, the upper surface in the vertical direction). The light-emitting element substrate 62 is provided with a plurality of light sources 64 arranged along one direction. In this embodiment, the light source 64 includes, for example, a plurality of light-emitting elements. As an example, the light source 64 is a light-emitting element array having a semiconductor substrate and a plurality of light-emitting elements formed on the semiconductor substrate along one direction. In this embodiment, the light source 64, i.e., the light-emitting element array, is arranged in a staggered pattern along one direction on the light-emitting element substrate 62. Note that the light source 64 may not be a light-emitting element array, but may be a single light-emitting element. Furthermore, each light-emitting element is composed of a light-emitting diode, a light-emitting thyristor, a laser element, or the like, and has, for example, a resolution of 2400 dpi when arranged along one direction. The light-emitting element substrate 62 is a substrate for causing one or more of the plurality of light sources 64 to emit light. In FIG. 6, only one light source 64 provided in the light irradiation unit 44 is shown, and the other light sources are not shown.

[0071] The light irradiation section 44 also includes a pair of mounting sections 66 provided on the surface of the light-emitting element substrate 62 opposite the support body 60, and a lens section 68 held in a sandwiched state between the upper ends of the pair of mounting sections 66.

[0072] The pair of mounting portions 66 and the lens portion 68 extend in one direction (the direction of arrow X) of the support body 60 (see FIG. 4, etc.). The lens portion 68 is disposed in a position facing the plurality of light sources 64, and a space is provided between the lens portion 68 and the plurality of light sources 64. In the exposure device 40, light emitted from the plurality of light sources 64 passes through the lens portion 68 and is irradiated onto the surface of the photosensitive drum 32 (see FIG. 1), which is an object to be irradiated.

[0073] The support 60 is made of a rectangular parallelepiped member. In this embodiment, the support 60 is made of a metal block, similar to the base 42. For example, the support 60 is made of steel or stainless steel. Here, the base 42 may be made of a metal block other than steel or stainless steel. For example, it may be made of aluminum, which has a higher thermal conductivity than steel or stainless steel and is lighter. However, if the thermal expansion coefficients of the base 42 and the support 60 differ, distortion or bending may occur. Therefore, from the viewpoint of suppressing distortion or bending, it is preferable that the base 42 and the support 60 are made of the same material.

[0074] A screw hole 74 into which the shaft portion 58B of the fastening member 58 is fastened is formed in the surface of the support body 60 facing the base body 42 (see FIG. 6). The screw hole 74 is provided in a position facing the through hole 84 of the base body 42.

[0075] The fastening member 58 is inserted into the recessed portion 82 of the base 42, and the shaft portion 58B of the fastening member 58 is fastened to the screw hole 74 of the support body 60 via the spacer 56, with the shaft portion 58B of the fastening member 58 passing through the through-hole 84 of the base 42. In this way, the light irradiation unit 44 is fixed to the base 42 from inside the recessed portion 82 of the base 42 by the fastening member 58. With the light irradiation unit 44 fixed to the base 42 by the fastening member 58, the spacer 56 is interposed between the base 42 and the support body 60.

[0076] Here, a method can be considered in which the fastening member 58 is used to fasten the support 60 from the front side (the light output surface side) to the front side of the base 42. However, unlike supports made of resin material or supports made of sheet metal, the support 60 of this embodiment is made of a heavy metal block. Therefore, the fastening member 58 must be sized to match the mass. In this case, space for the large fastening member 58 is required on the front side of the support 60, which increases the size of the support 60. Therefore, in this embodiment, the support 60 is fastened from the back side.

[0077] Furthermore, in a configuration in which fastening members 58 are provided not only on both end sides of support body 60 but also on the central side, the presence of light source 64 on the central side makes it difficult to configure the fastening from the front side of support body 60. Therefore, by configuring the fastening from the back side of base 42, it becomes possible to fasten both end sides and the central side of support body 60 only from the back side of base 42.

[0078] The screw hole 74 and the recessed portion 82 of the base 42 are provided at a position that overlaps with the light source 64 when viewed from the optical axis direction of the light source 64. With this configuration, heat generated by the light source 64 is more easily dissipated toward the base 42 via the fastening member 58 compared to when the screw hole 74 and the recessed portion 82 are provided at a position that does not overlap with the light source 64.

[0079] As shown in Figures 6, 7, 8, and 9, the light irradiation unit 44 has a drive substrate 72 attached to the support body 60 via a fixture 70. Here, the drive substrate 72 is an example of a substrate. The drive substrate 72 extends in one direction (the direction of arrow X). The length of the drive substrate 72 in one direction is shorter than the length of the support body 60 in one direction (see Figure 8). The drive substrate 72 is a substrate for driving the light irradiation unit 44, and for example, an ASIC substrate (application specific integrated circuit) or the like is used.

[0080] The mounting fixture 70 includes a fastening bolt 70A and a tube 70B disposed between the support body 60 and the drive substrate 72 (see FIG. 9). As an example, the tube 70B is made of metal and is joined to the drive substrate 72 by soldering or the like. Although not shown, the drive substrate 72 has an opening formed therein that communicates with the through-hole of the tube 70B. The shaft of the fastening bolt 70A is configured to pass through the tube 70B. The shaft of the fastening bolt 70A passes through the tube 70B from the drive substrate 72 side and is fastened to the support body 60, thereby mounting the drive substrate 72 to the support body 60. The drive substrate 72 is mounted to the support body 60 by two mounting fixtures 70 disposed at both ends of the drive substrate 72 in one direction.

[0081] The surface (i.e., plate surface) of the drive substrate 72 is arranged along the inner side portion 60A in the short-side direction of the support 60 in the short-side direction (direction of arrow Y) of the base 42 (see FIG. 7). Here, the inner side portion 60A of the support 60 refers to the side closer to the center of the base 42 in the short-side direction.

[0082] A gap is formed between the inner side portion 60A of the support body 60 and the surface (plate surface) of the drive substrate 72 by the tubular body 70B of the mounting fixture 70. In other words, the drive substrate 72 is attached by the mounting fixture 70 without directly contacting the inner side portion 60A of the support body 60 in the light irradiation unit 44.

[0083] The inner side portion 60A of the support 60 is an inclined surface that is inclined inward with respect to the surface 42A of the base 42. Like the inner side portion 60A, the plate surface of the drive substrate 72 is also inclined inward with respect to the surface 42A of the base 42.

[0084] The three light emitting units 44 each have a drive substrate 72 provided on the inner side portion 60A of the support 60.

[0085] 3 and 4, the drive substrate 72 provided in one light irradiation unit 44 in a side view is provided at a position that does not overlap with another light irradiation unit 44 adjacent to the one light irradiation unit 44. The lengths in one direction (the direction of arrow X) of the drive substrates 72 arranged in each of the three light irradiation units 44 on the base 42 are the same, and are shorter than the length of the light irradiation unit 44 arranged in the center in one direction that does not overlap with the light irradiation units 44 on both sides in one direction.

[0086] 7, 8, and 9, three flexible cables 100 are connected to the light-emitting element substrate 62 on the upper side of the support 60, and the three flexible cables 100 extend from the upper part of the inner side portion 60A of the support 60 to the outside of the support 60. The three flexible cables 100 extending to the outside of the support 60 are electrically connected to three drive elements 73 provided on the drive substrate 72, respectively. The drive elements 73 may be, for example, integrated circuits.

[0087] Furthermore, a connector 104 is provided at the middle of the drive substrate 72 in one direction (the direction of arrow X) to which a flat cable 102 from outside the light irradiation unit 44 is electrically connected. The connection port of the connector 104 is arranged in a direction intersecting the surface (plate surface) of the drive substrate 72. The connection portion of the flat cable 102 can be inserted into and removed from the connector 104 in a direction intersecting the surface (plate surface) of the drive substrate 72. Here, the flat cable 102 is an example of wiring.

[0088] As shown in FIG. 7 , the flat cable 102 connected to the connector 104 extends from the drive substrate 72 to the opposite side of the support 60. A through-hole 106 that penetrates the base 42 in the vertical direction (arrow Z direction) is formed at a position corresponding to the position where the flat cable 102 is connected to the drive substrate 72. The through-hole 106 is provided on the lateral side of the drive substrate 72 in the base 42, in the short-side direction (arrow Y direction) of the base 42, at a position opposite the light irradiation unit 44 that includes the drive substrate 72 (i.e., a position where the light irradiation unit 44 is not disposed). The flat cable 102 is inserted through the through-hole 106 of the base 42 and routed inside the lower cover 50 on the back surface 42B side of the base 42. In other words, the flat cable 102 is disposed inside the lower cover 50.

[0089] 4 and 5, a flat cable 102 is connected to the drive substrate 72 provided in each of the three light irradiation units 44 via a connector 104. A through-hole 106 is provided in the base 42 on the lateral side of the drive substrate 72 of each of the three light irradiation units 44. The flat cable 102 of each of the three light irradiation units 44 is inserted into the through-hole 106 of the base 42, and extends inside the lower cover 50 on the rear surface 42B side of the base 42 (see FIG. 7).

[0090] As an example, the light irradiating unit 44 has a height longer than a width longer than a length in a direction perpendicular to one direction (the direction of the arrow X). That is, the light irradiating unit 44 has a length longer in the up-down direction (the direction of the arrow Z) than a length in the short side direction (the direction of the arrow Y). Therefore, the center of gravity of the light irradiating unit 44 is higher than when the light emitting unit has a height shorter than a width longer than a length in the direction perpendicular to one direction.

[0091] 6, the spacer 56 is sandwiched between the base 42 and the light irradiation unit 44 in the optical axis direction of the light source 64. As an example, the spacer 56 is plate-shaped and made of one member (i.e., a single member). In this embodiment, the spacer 56 is U-shaped when viewed in the optical axis direction of the light source 64. The spacer 56 includes a main body 56A and a recessed portion 56B cut out from one side of the main body 56A.

[0092] The spacer 56 is disposed on the inclined surface 80A of the recess 80 of the base 42. At the position where the spacer 56 is disposed on the inclined surface 80A, the thickness of the spacer 56 is equal to or greater than the depth of the recess 80. The fastening member 58 fixes the light irradiation unit 44 to the base 42 in a manner that a compressive load is applied to the spacer 56.

[0093] As shown in FIG. 7 , the bracket 48 has a function of holding the flat cable 102. Here, the bracket 48 is an example of a holding member. More specifically, the bracket 48 includes a U-shaped support portion 48A that protrudes from the back surface 42B of the base 42 toward the opposite side from the light irradiation portion 44, and a pair of attachment portions 48B that are bent inward from the upper end of the support portion 48A (i.e., toward the inside in the short direction of the base 42). The support portion 48A includes a flat portion 49 that faces the back surface 42B of the base 42, at a middle portion on the lower side of the U-shape. The support portion 48A has a shape such that the side opposite the flat portion 49 opens toward the base 42. The pair of attachment portions 48B are attached to the base 42 by fastening members 110 while in surface contact with the back surface 42B of the base 42.

[0094] A plurality of brackets 48 are provided at intervals in one direction (the direction of arrow X) of the base 42 (see FIG. 5). A flat cable 102 is held on a flat surface 49 of the support portion 48A. The flat cable 102 is supported by the plurality of brackets 48, and is arranged inside the lower cover 50 along one direction (the direction of arrow X) of the base 42.

[0095] 4 and 7, the lower cover 50 covers the harnesses 46 and flat cables 102 electrically connected to the three light irradiators 44, respectively. The lower cover 50 is attached to the lower side of the base 42 in the up-down direction (i.e., the side of the back surface 42B of the base 42 shown in FIG. 5), protrudes from the base 42 on the side opposite the light irradiators 44, and covers part of the back surface 42B of the base 42. In this embodiment, the lower cover 50 has a U-shaped cross section, and the upper end of the lower cover 50 is attached to both sides of the base 42 in the short direction (direction of arrow Y) by a plurality of fastening members 86. The lower cover 50 can be attached to and detached from the base 42 by fastening and removing the plurality of fastening members 86.

[0096] The lower cover 50 is configured to raise the position of the base 42 when the lower surface is placed flat. Because the base 42 is made of a metal block, raising the position of the base 42 raises the center of gravity of the exposure device 40.

[0097] 2, 6, and 7, the side covers 52 are provided at both ends in the short-side direction (arrow Y direction) of the base 42. The side covers 52 are arranged in one direction (arrow X direction) on the sides of the three light irradiators 44. As a result, the side covers 52 have the function of protecting the three light irradiators 44 from the outside.

[0098] The side cover 52 is provided at a position overlapping with the three light irradiation units 44 in a side view (viewed from the direction of arrow Y) of the exposure device 40. The length of the side cover 52 in one direction (the direction of arrow X) is longer than the length region of the base 42 in which the three light irradiation units 44 are arranged (see FIGS. 2 and 3).

[0099] 7, support portions 122 that support the side covers 52 are provided on the inside of the side covers 52. Mounting portions 120 are provided on the surface 42A of the base 42 at the ends in the short-side direction (arrow Y direction), and the support portions 122 are supported by the mounting portions 120. The support portions 122 come into contact with the side covers 52, thereby supporting the side covers 52 so that they do not fall toward the light irradiation unit 44. The support portions 122 are provided on the side covers 52 on both sides in the short-side direction of the base 42. Although not shown, a plurality of support portions 122 are provided at intervals in one direction (arrow X direction) of the side covers 52.

[0100] (Position adjustment section 130) 10 to 12, the position adjustment unit 130 is a mechanism that adjusts the distance between the light emitting unit 41 and the photosensitive drum 32. Specifically, the position adjustment unit 130 adjusts the position of the light emitting unit 41 with respect to the photosensitive drum 32. More specifically, the position adjustment unit 130 moves the light emitting unit 41 in the light emission direction to adjust the position of the light emitting unit 41 with respect to the photosensitive drum 32. In this embodiment, the light emission direction of the light emitting unit 41 is substantially the same as the Z direction.

[0101] As shown in FIG. 10, the position adjustment unit 130 includes a contact member 132, a support member 134, and a moving member 136.

[0102] -Contact member 132- 10, the contact member 132 is a member whose outer peripheral surface 132A contacts the surface 42A of the base 42. The contact member 132 is disk-shaped and rotatably supported by a support member 134. Specifically, the contact member 132 is supported by the support member 134 so as to rotate relative to the support member 134. As an example, the contact member 132 of this embodiment is a ball bearing.

[0103] -Support member 134- The support member 134 is a member that rotatably supports the contact member 132. The support member 134 supports the contact member 132 so that it can rotate relative to the support member 134. As shown in FIGS. 10 and 12 , the support member 134 is a substantially cylindrical shaft member, and both axial ends thereof are received by a pair of receiving portions 138. Specifically, the pair of receiving portions 138 are arranged opposite each other in the X direction, which is the short-side direction of the base 42. The pair of receiving portions 138 are portions that receive the support member 134 so that it can rotate with the X direction as its axial direction and move in the light irradiation direction. In other words, the contact member 132 is disposed between the pair of receiving portions 138 of the support member 134.

[0104] 12, the pair of receiving portions 138 are hole walls of elongated holes formed in a pair of support plates 140 arranged opposite each other in the X direction with the contact member 132 sandwiched therebetween. The longitudinal direction of these elongated holes is in the Z direction. Therefore, both axial ends of the support member 134 can be supported rotatably and movably in the light irradiation direction. In addition, stoppers (not shown) are attached to both axial ends of the support member 134 to prevent it from coming off.

[0105] As shown in FIG. 11, the outer diameter D1 of the contact member 132 is larger than the outer diameter D2 of the support member 134.

[0106] As shown in FIG. 11, the moving member 136 is a member that comes into contact with the support member 134 and moves the support member 134 in the light emission direction of the light emitting section 41.

[0107] The moving member 136 is movable in the X direction. Specifically, the position adjustment unit 130 has a feed member 142 and a drive source 144, and the feed member 142 moves the moving member 136 in the X direction. In this embodiment, the feed member 142 is a feed screw, which is an example of a screw member. The feed member 142 penetrates a connecting plate 146 that connects the X-direction ends of the pair of support plates 140. The drive source 144 is connected to one axial end of the feed member 142. The drive source 144 drives and rotates the feed member 142. In this embodiment, the drive source 144 is an electric motor, for example, but the present invention is not limited to this configuration. The drive source 144 is attached to a mounting plate 148 that protrudes from the connecting plate 146 to one side in the X direction (the left side in FIG. 11 , or the front side in the device depth direction). In this embodiment, a housing 131 of the position adjustment unit 130 is configured by the pair of support plates 140, the connecting plate 146, and the mounting plate 148. The housing 131 is attached to a frame (not shown) of the image forming unit 14.

[0108] The moving member 136 is provided with a conversion section 150 that converts the moving force in the X direction applied by the feed member 142 into a moving force for moving the support member 134 in the light irradiation direction. Specifically, the conversion section 150 is provided at a portion of the moving member 136 that contacts the support member 134, and is an inclined surface that is inclined with respect to the X direction. More specifically, as shown in FIG. 12 , the moving member 136 has a pair of conversion sections 150 (a pair of inclined surfaces), and the pair of conversion sections 150 contacts both axially opposite portions of the support member 134, sandwiching the contact member 132 therebetween. As an example, the moving member 136 of this embodiment is formed in a rectangular parallelepiped shape, and a groove 136A extending in the X direction is formed in a portion corresponding to the contact member 132, into which part of the outer periphery of the contact member 132 fits. The pair of conversion sections 150 are formed on both sides of the groove 136A of the support member 134, sandwiching the groove 136A.

[0109] 10 , the base 42 is pressed toward the position adjustment unit 130 by a pressing unit 129 disposed on the opposite side of the position adjustment unit 130. That is, the base 42 is clamped and pressed in the Z direction between the position adjustment unit 130 and the pressing unit 129. When the moving member 136 moves in the X direction, a moving force in the Z direction is applied to the support member 134 by the inclined surface of the conversion unit 150 via the outer circumferential surface of the support member 134. When this moving force in the Z direction is applied to the support member 134, it is transmitted from the support member 134 via the contact member 132 to the base 42, pushing back the pressing unit 129, and the base 42 moves in the Z direction, i.e., the position is adjusted.

[0110] 12, the feed member 142 that penetrates the movable member 136 and the contact member 132 overlap in the light irradiation direction. Furthermore, as shown in Fig. 11, in this embodiment, as an example, a straight line SL that passes through the contact point between the contact member 132 and the base 42 and the contact point between the movable member 136 and the support member 134 is aligned along the light irradiation direction of the light-emitting unit 41.

[0111] Furthermore, the coefficient of friction between the contact member 132 and the base 42 is smaller than the coefficient of friction between the support member 134 and the contact member 132. Specifically, in this embodiment, the contact member 132 is a ball bearing, so the contact member 132 rotates relative to the support member 134 before friction occurs between the contact member 132 and the base 42.

[0112] Furthermore, the ends of the pair of support plates 140 in the Z direction are connected to each other by a connecting plate 147. An opening 147A is formed in this connecting plate 147, and part of the outer periphery of the contact member 132 protrudes from this opening 147A. Part of the protruding part of the contact member 132 is in contact with the surface 42A of the base 42. In the image forming apparatus 10 of this embodiment, measuring devices (not shown) provided on both ends of the base 42 measure the distance from the light-emitting unit 41 to the surface of the photosensitive drum 32, and the measurement information is sent to a control device (not shown). The control device operates each position adjustment unit 130 based on the measurement information. Specifically, the drive amount of the drive source 144 is adjusted based on the measurement information. When the value measured by the measuring device falls within a preset range, the control device stops the operation of the drive source 144. The position adjustment of the light-emitting unit 41 using the position adjustment unit 130 may be performed when the light-emitting unit 41 is attached to the photosensitive drum 32, or may be performed after a predetermined time (period) has elapsed.

[0113] Next, the operation and effects of this embodiment will be described. In the exposure device 40 of this embodiment, the contact member 132 is supported by the support member 134 so as to be rotatable relative to the support member 134. Therefore, compared to a configuration in which the contact member 132 is fixed to the support member 134, it is possible to suppress positional deviation in the direction perpendicular to the light emission direction of the light emitting unit 41.

[0114] In the exposure device 40, the coefficient of friction between the contact member 132 and the base 42 is smaller than the coefficient of friction between the support member 134 and the contact member 132. Therefore, even if a force in the Z direction acts on the support member 134 due to movement of the movable member 136, the contact member 132 rotates relative to the support member 134, thereby preventing excessive frictional force from occurring between the contact member 132 and the base 42. Therefore, in the exposure device 40, positional deviation in the direction perpendicular to the light emission direction of the light emitting unit 41 can be reduced compared to a configuration in which the coefficient of friction between the contact member 132 and the base 42 is equal to or greater than the coefficient of friction between the support member 134 and the contact member 132.

[0115] In the exposure device 40, the length in one direction can be made shorter than when the support member 134 extends in one direction.

[0116] In the exposure device 40, the size of the device in the light irradiation direction can be made more compact than in a configuration in which the moving member 136 moves in the light irradiation direction to move the support member 134 in the light irradiation direction.

[0117] In the exposure apparatus 40, the coefficient of friction between the contact member 132 and the substrate 42 is smaller than the coefficient of friction between the support member 134 and the contact member 132, thereby reducing the friction between the moving member 136 and the support member 134.

[0118] In the exposure apparatus 40, tilting of the support member 134 can be suppressed compared to a configuration in which the converting portion 150, which is the inclined surface of the moving member 136, contacts only one side of the support member 134 with the contact member 132 sandwiched therebetween.

[0119] In the exposure device 40, compared to a configuration in which the contact member 132 is positioned outside the opposing receiving portion 138 of the support member 134, it is possible to suppress twisting of the substrate 42 that occurs when the contact member 132 adjusts the position of the substrate 42 in the light irradiation direction.

[0120] In the exposure device 40, compared to a configuration in which the outer diameter D1 of the contact member 132 is equal to or smaller than the outer diameter D2 of the support member 134, interference of the support member 134 with the base 42 can be suppressed even if the base 42 is wide in the short direction.

[0121] In the exposure device 40, loss of the moving force of the moving member 136 transmitted to the support member 134 can be reduced compared to a configuration in which the feed member 142 and the contact member 132 are misaligned in the light irradiation direction.

[0122] In the exposure device 40, the amount of movement of the moving member 136 in one direction can be finely adjusted, compared to a configuration in which the moving member 136 is moved in one direction by rotating a belt to which the moving member 136 is attached.

[0123] In the exposure device 40, positional deviation of the light-emitting section 41 in a direction perpendicular to the light irradiation direction can be suppressed compared to a configuration in which the straight line SL passing through the contact point between the contact member 132 and the base 42 and the contact point between the movable member 136 and the support member 134 is inclined with respect to the light irradiation direction.

[0124] The image forming apparatus 10 uses the exposure device 40 described above, and therefore can form an image with high precision.

[0125] In the position adjustment unit 130 of the above-described embodiment, the contact member 132 is disposed between the pair of conversion units 150 of the moving member 136, but the present invention is not limited to this configuration. For example, as in the position adjustment unit 160 shown in Figures 13 and 14, a configuration in which two contact members 132 are disposed on the support member 134 with a gap in the axial direction may be used. Even in this case, the same effects as those of the position adjustment unit 130 can be obtained.

[0126] In the position adjustment unit 130 of the above-described embodiment, the support member 134 is moved in the light irradiation direction by moving the moving member 136 in the X direction. However, the present invention is not limited to this configuration. For example, as in the position adjustment unit 170 shown in FIGS. 15 and 16 , a configuration in which an eccentric cam serving as the moving member 172 moves the support member 134 in the light irradiation direction may be used. Specifically, a rotation shaft 174 of the moving member 172 is rotatably supported by a pair of support plates 140. A driving force is applied to this rotation shaft 174 from a drive source 176. The drive source 176 is attached to a mounting plate 178 that protrudes from one of the support plates 140. Note that the drive source 176 is not particularly limited as long as it can rotate and drive the rotation shaft 174. For example, an electric motor may be used. Furthermore, the drive source 176 and the rotation shaft 174 may be connected via, for example, a belt or gears. In the position adjustment unit 170, when the moving member 172 rotates around the rotation axis 174, a moving force in the Z direction acts on the support member 134 in contact with the moving member 172. In other words, the moving member 172 is pressed, and the position of the base 42 in the Z direction is adjusted. Even in this case, the same effect as that of the position adjustment unit 130 can be obtained.

[0127] In the position adjustment unit 130 of the above-described embodiment, a pair of conversion units 150 is provided on the moving member 136, but the present invention is not limited to this configuration. For example, a plurality of moving members each having a conversion unit 150 may be moved in the X direction by a corresponding feed member to move the support member 134 in the light irradiation direction. Even in this case, the same effect as that of the position adjustment unit 130 can be obtained. Furthermore, twisting of the base body that occurs when the contact member adjusts the position of the base body in the light irradiation direction with the contact member can be suppressed while maintaining the balance between the contact member and the moving member.

[0128] In the above-described embodiment, a feed screw is used as an example of the feed member 142, but the present invention is not limited to this configuration. There are no particular limitations on the configuration of the feed member 142 as long as it can move the moving member 136 in the X direction. For example, a spring material, a cylinder, etc. may be used as an example of the feed member 142.

[0129] In the exposure device and image forming apparatus of the above-described embodiment, three light-emitting units are arranged on the substrate, but the present invention is not limited to this configuration. For example, one light-emitting unit, two light-emitting units, or four or more light-emitting units may be arranged on the substrate. Furthermore, the positions of the multiple light-emitting units arranged on the substrate can be set appropriately.

[0130] Furthermore, in the exposure device and image forming apparatus of the above-described embodiments, the base is configured as a metal block, but the present invention is not limited to this. The material or shape of the base can be changed. For example, the base may be configured as a resin or as another metal material such as sheet metal. Furthermore, the components of the light-emitting unit or the shape of the components of the light-emitting unit can be changed. Although the support of the light-emitting unit is configured as a metal block, the present invention is not limited to this. The material or shape of the support can be changed. For example, the support may be configured as a resin or as another metal material such as sheet metal.

[0131] Furthermore, the exposure apparatus and image forming apparatus of the above-described embodiments can be used in applications involving components to which photolithography is applied, such as forming color filters in the manufacturing process of liquid crystal displays (LCDs), exposing dry film resist (DFR) in the manufacturing process of thin film transistors (TFTs), exposing dry film resist (DFR) in the manufacturing process of plasma display panels (PDPs), exposing photosensitive materials such as photoresist in the manufacturing process of semiconductor elements, exposing photosensitive materials such as photoresist in the platemaking process of printing other than offset printing, such as gravure printing, or exposing photosensitive materials in the manufacturing process of watch parts. Here, photolithography refers to a technique for generating a pattern consisting of exposed and unexposed areas by exposing the surface of a material on which a photosensitive material is placed in a pattern.

[0132] The exposure device and image forming device can use either a photon mode photosensitive material, in which information is recorded directly by exposure, or a heat mode photosensitive material, in which information is recorded by heat generated by exposure. The light source of the image forming device can be an LED element or a laser element, depending on the object to be exposed.

[0133] Although the present invention has been described in detail with reference to specific embodiments, it will be apparent to those skilled in the art that the present invention is not limited to such embodiments, and that various other embodiments are possible within the scope of the present invention. [Explanation of symbols]

[0134] 10 Image forming device 32 Photosensitive drum (an example of an image-holding member) 40 Exposure equipment 42 Base 130 Position adjustment section 132 Contact member 134 Support member 136 Moving parts 138 Receiving part 140 Support plate 142 Feed member 150 Conversion Unit 160 Position adjustment section 170 Position adjustment section 172 Moving parts

Claims

1. a light-emitting section having a base and a light-emitting element disposed on the base; a position adjustment unit including: a contact member whose outer periphery is in contact with the base body; a support member that rotatably supports the contact member; and a moving member that is in contact with the support member and moves the support member in the light irradiation direction of the light emitting unit; Equipped with the substrate extends in one direction, a plurality of the light-emitting elements are arranged in the one direction, the support member is a shaft member, The position adjustment unit has a receiving portion that receives the shaft member rotatably about an axial direction that is perpendicular to the one direction and movable in the light irradiation direction.

2. 2. The exposure apparatus of claim 1, wherein a coefficient of friction between the contact member and the substrate is less than a coefficient of friction between the support member and the contact member.

3. The moving member is movable in the one direction, 3. The exposure apparatus according to claim 1, wherein the moving member is provided with a conversion section that converts the one-directional moving force into a moving force for moving the shaft member in the light irradiation direction.

4. 4. The exposure apparatus according to claim 3, wherein the conversion portion is provided at a portion of the moving member that comes into contact with the shaft member, and is an inclined surface that is inclined with respect to the one direction.

5. the moving member has a pair of the inclined surfaces, 5. The exposure apparatus according to claim 4, wherein the pair of inclined surfaces are in contact with both side portions of the shaft member, with the contact member sandwiched therebetween.

6. The receiving portions are disposed opposite each other in a lateral direction of the base body, The opposing receiving portions each receive the shaft member, 6. The exposure apparatus according to claim 1, wherein the contact member is disposed between the opposing receiving portions of the shaft member.

7. the contact member is one, and the moving members are two, arranged in a direction perpendicular to the one direction; 5. The exposure apparatus according to claim 1, wherein the contact member is disposed between two of the moving members.

8. 8. The exposure apparatus according to claim 1, wherein the outer diameter of the contact member is larger than the outer diameter of a shaft member that is the support member.

9. the position adjustment unit has a feed member that moves the moving member in the one direction, 9. The exposure apparatus according to claim 1, wherein the feed member and the contact member overlap in the light irradiation direction.

10. the feed member is a screw member that extends in the one direction and moves the moving member in the one direction by rotating about an axis, 10. The exposure apparatus according to claim 9, wherein the position adjustment unit further comprises a drive source that rotationally drives the screw member.

11. 11. The exposure apparatus according to claim 1, wherein a straight line passing through a contact point between the contact member and the base body and a contact point between the moving member and the shaft member is aligned with the light irradiation direction.

12. an image carrier; an exposure device according to any one of claims 1 to 11, which exposes the image carrier to light to form an electrostatic latent image and is capable of adjusting the distance between the image carrier and a light-emitting element; a developing device that develops the electrostatic latent image on the image carrier; An image forming apparatus comprising:

Citation Information

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