Light emitting device, exposure apparatus, and image forming apparatus

Abstract

The present application provides a light emitting device, an exposure device, and an image forming apparatus, in which deformation of a frame caused by self-weight of a restraining member is suppressed. A light emitting device includes: a frame that is a resin frame extending in one direction and holding a light emitting portion that emits light upward in a height direction intersecting the one direction, and has a positioned portion and a forced portion on the upper side and the lower side of both end portions in the one direction, respectively, which contact with a positioning member in the height direction, and a force receiving mechanism that receives a force from a force applying mechanism that applies a force to the frame in a manner that the positioned portion contacts with the positioning member; and a restraining member that extends in the one direction, is fixed to the frame, and restrains the frame from deforming, and at least one end portion in the one direction is sandwiched between the forced portion and the force applying mechanism.

Description

TECHNICAL FIELD

[0001] The present application relates to a light emitting device, an exposure apparatus, and an image forming apparatus. BACKGROUND

[0002] Patent Document 1 describes an exposure apparatus including a substrate having a plate-shaped main body portion extending in one direction, a plurality of light emitting elements mounted on one face of the main body portion, and a heat generating element mounted on the other face of the main body portion and generating heat in conjunction with light emitting operation of the light emitting elements; a resin frame extending in the one direction and having a through hole, and the substrate is fixed inside the through hole in such a manner that a plate thickness direction of the substrate becomes a through direction of the through hole; and a suppression member extending in the one direction and being embedded in the through hole, and suppressing thermal deformation of the frame.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2018-001567 SUMMARY

[0004] The present application relates to a light emitting device, an exposure apparatus, and an image forming apparatus.

[0005] The light emitting device according to the first aspect includes a frame extending in one direction and being a resin frame that holds a light emitting portion that emits light upward in a height direction intersecting the one direction, and has a positioned portion and a forced portion on the upper side and the lower side of both end portions in the one direction, respectively, which contact with a positioning member in the height direction, and which receive an action force from a force applying mechanism that applies a force to the frame in such a manner that the positioned portion contacts with the positioning member, and a suppression member extending in the one direction and being fixed to the frame and suppressing deformation of the frame, and at least one end portion in the one direction is sandwiched between the forced portion and the force applying mechanism.

[0006] The light emitting device according to the second aspect includes the light emitting device according to the first aspect, and both end portions in the one direction of the suppression member are sandwiched between the forced portion and the force applying mechanism.

[0007] The light emitting device according to the third aspect includes the light emitting device according to the second aspect, and a portion between both end portions in the one direction of the suppression member is away from a lower surface of the frame.

[0008] The light emitting device according to the fourth aspect is the light emitting device according to any one of the first to third aspects, in which either of the end portion and the force receiving portion has a contact portion that makes point or line contact with the other of the end portion and the force receiving portion.

[0009] The light emitting device according to the fifth aspect is the light emitting device according to the fourth aspect, in which the end portions on both sides in the one direction of the suppression member are sandwiched between the force receiving portion of the frame and the force applying mechanism, and a portion between the end portions on both sides in the one direction is away from the lower surface of the frame, and at least one of the contact portions makes line contact with the other of the end portion and the force receiving portion in a direction intersecting the one direction and the height direction.

[0010] The light emitting device according to the sixth aspect is the light emitting device according to the fourth or fifth aspect, in which the contact portion is provided to the frame.

[0011] The exposure device according to the seventh aspect has the light emitting device according to any one of the first to sixth aspects, and an optical member that exposes light emitted from the light emitting device to an exposure target.

[0012] The image forming apparatus according to the eighth aspect includes: an image holding body; the exposure device according to the seventh aspect that forms an electrostatic latent image by imaging light on the charged image holding body; a positioning member that positions a position of the exposure device in the height direction with respect to the image holding body by contacting the positioned portion; a force applying mechanism that applies a force to the frame via the end portion to make the positioned portion contact the positioning member; and a developing device that develops the electrostatic latent image of the image holding body to form an image.

[0013] Effects of Invention

[0014] According to the light emitting device according to the first aspect, in a structure in which a suppression member that suppresses deformation of a frame is fixed to the frame, deformation of the frame caused by the weight of the suppression member is suppressed compared to a structure in which the frame directly receives a force from a force applying mechanism in a force receiving portion.

[0015] According to the light emitting device according to the second aspect, deformation of the frame caused by the weight of the suppression member is suppressed compared to a structure in which only one end portion of the suppression member in one direction is sandwiched between the force receiving portion of the frame and the force applying mechanism.

[0016] According to the light emitting device according to the third aspect, deformation of the frame accompanying deformation of the suppression member is suppressed compared to a structure in which the entire suppression member contacts the lower surface of the frame in the height direction.

[0017] According to the light emitting device according to the fourth aspect, compared with a structure in which the end portion of the suppression member is in surface contact with the force receiving portion of the frame, deformation of the frame accompanying deformation of the suppression member is suppressed.

[0018] According to the light emitting device according to the fifth aspect, compared with a structure in which the end portions on both sides in one direction are in point contact with the force receiving portion of the frame, the posture of the light emitting device subjected to force from the force applying mechanism via the suppression member is stabilized.

[0019] According to the light emitting device according to the sixth aspect, compared with a structure in which the contact portion in point or line contact with the contact receiving portion of the frame is provided to the suppression member, the suppression member is easily formed.

[0020] According to the exposure device according to the seventh aspect, in a structure in which the suppression member that suppresses deformation of the frame is fixed to the frame, compared with a structure in which the frame of the light emitting device directly receives force from the force applying mechanism in the force receiving portion, exposure defects are suppressed.

[0021] According to the image forming device according to the eighth aspect, in a structure in which the suppression member that suppresses deformation of the frame is fixed to the frame, compared with a structure in which the frame of the light emitting device directly receives force from the force applying mechanism in the force receiving portion, image forming defects are suppressed. BRIEF DESCRIPTION OF DRAWINGS

[0022] Embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0023] Figure 1 is a side view of an exposure device according to an embodiment of the present application;

[0024] Figure 2 is an exploded perspective view of an exposure device according to an embodiment of the present application;

[0025] Figure 3 is an RT-RT sectional view of Figure 1

[0026] Figure 4 is an LT-LT sectional view of Figure 1

[0027] Figure 5 is a bottom view of an exposure device according to an embodiment of the present application;

[0028] Figure 6 (A) of is an enlarged side view of one end portion of a frame according to an embodiment of the present application, Figure 6 (B) of is an enlarged bottom view of one end portion of a frame according to an embodiment of the present application;

[0029] Figure 7 ​​(B) is an enlarged bottom view of the other end portion of the frame of the embodiment of the present application, Figure 7 (B) is an enlarged bottom view of the other end portion of the frame of the embodiment of the present application,

[0030] Figure 8 is a schematic front view showing the structure of the image forming apparatus to which the embodiment of the present application is applied.

[0031] Symbol explanation

[0032] 10 - image forming apparatus, 36 - photosensitive drum (one example of image holding body), 40 - developing apparatus, 50 - exposure apparatus, 50a - light emitting apparatus, 52 - lens array (one example of optical member), 56 - light emitting substrate (one example of light emitting section), 60 - frame, 60b - lower surface section (one example of force applying section), 68 - flat section 68 (one example of positioning section), 70 - protruding section (one example of contact section), 72 - protruding section (one example of contact section), 80 - suppression member, 86 - end portion, 90 - positioning member, 94 - force applying mechanism. DETAILED DESCRIPTION

[0033] According to Figures 1-8 An example of the light emitting apparatus, the exposure apparatus, and the image forming apparatus to which the embodiment of the present application is applied will be described.

[0034] In addition, in the following description, when the image forming apparatus 10 is viewed from the front side of the user (omitted from the drawing) standing side, the apparatus up-and-down direction (height direction), the apparatus width direction (horizontal direction), and the apparatus depth direction (horizontal direction) are respectively denoted as the H direction, the W direction, and the D direction. Also, when it is necessary to distinguish one side and the other side of each of the apparatus up-and-down direction, the apparatus width direction, and the apparatus depth direction, the upper side of the image forming apparatus 10 is denoted as the +H side, the lower side is denoted as the -H side, the right side is denoted as the +W side, the left side is denoted as the -W side, the inside is denoted as the -D side, and the front side is denoted as the +D side when viewed from the front side.

[0035] (Image forming apparatus 10)

[0036] The image forming apparatus 10 to which the present embodiment is applied is an electrophotographic image forming apparatus that forms a toner image in a sheet member P as a recording medium and performs fixing. As shown in Figure 8 The image forming apparatus 10 has a frame 10A as an apparatus main body, a housing portion 26, a conveying portion 16, and an image forming portion 20. The housing portion 26 has a function of housing the sheet member P. The conveying portion 16 has a function of conveying the sheet member P housed in the housing portion 26 to the image forming portion 20 side.

[0037] The image forming unit 20 includes photosensitive units 18Y, 18M, 18C, and 18K, a transfer unit 14, and a fixing unit 48. Additionally, the symbols ending in "Y" indicate yellow, "M" indicate magenta, "C" indicate cyan, and "K" indicate black.

[0038] When viewed from the front of the image forming apparatus 10, photoreceptor units 18Y, 18M, 18C, and 18K are arranged in an array inside the frame 10A. Photoreceptor units 18Y, 18M, 18C, and 18K have the same structure except for the toner used (not shown). Therefore, a symbol representing the structure of the photoreceptor unit is assigned to photoreceptor unit 18K, while photoreceptor units 18Y, 18M, and 18C are omitted. Furthermore, when not specifically distinguishing between photoreceptor units 18Y, 18M, 18C, and 18K, the last letter of the designation is omitted.

[0039] The photosensitive unit 18 includes a photosensitive drum 36, a charging device 38, an exposure device 50, and a developing device 40. The photosensitive drum 36 is configured to rotate axially about the direction in which the image forming apparatus 10 is viewed from the front, and rotates counterclockwise when viewed from the front of the image forming apparatus 10 by a motor (not shown). Furthermore, the photosensitive drum 36 has the function of retaining an electrostatic latent image on its outer peripheral surface. The photosensitive drum 36 is an example of an image holder. The charging device 38 has the function of charging the outer peripheral surface of the photosensitive drum 36 to a predetermined potential. The exposure device 50 is positioned at a predetermined distance from the photosensitive drum 36. The exposure device 50 has the function of imaging light onto the charged photosensitive drum 36 to form an electrostatic latent image. The developing device 40 has the function of developing the electrostatic latent image formed on the photosensitive drum 36 using a developer containing a toner (not shown) to form a toner image. The exposure device 50 will be described in detail later.

[0040] And, as Figure 1 As shown, the photoreceptor unit 18 also includes a positioning member 90 that contacts the planar portion 68 of the exposure apparatus 50 (described later) and positions the exposure apparatus 50 relative to the photosensitive drum 36. Furthermore, the photoreceptor unit 18 also includes a force-applying mechanism 94 that applies force to the exposure apparatus 50 to bring the planar portion 68 of the exposure apparatus 50 into contact with the positioning member 90. Details of the positioning member 90 and the force-applying mechanism 94 will be described later.

[0041] The transfer unit 14 is configured to include an intermediate transfer belt 22, a plurality of primary transfer rollers 44, a drive roller 32, a secondary transfer roller 34, and an opposing roller 46. The intermediate transfer belt 22 is an annular conveyor belt whose inner circumference is supported by the primary transfer rollers 44, the drive rollers 32, and the secondary transfer rollers 34, and rotates clockwise when viewed from the front of the image forming apparatus 10 by the drive rollers 32.

[0042] The transfer unit 14 has a function of transferring the toner image formed by the photoreceptor units 18Y, 18M, 18C, 18K to the sheet member P conveyed from the conveyance section 16 via the intermediate transfer belt 22 and conveying to the fixing unit 48.

[0043] The fixing unit 48 has a function of fixing the toner image transferred to the sheet member P by the transfer unit 14 to the sheet member P and discharging the sheet member P to the outside of the apparatus.

[0044] {Exposure device 50}

[0045] Next, the exposure device 50 will be described.

[0046] As shown in Figure 2 , the exposure device 50 is provided with a light emitting device 50a, a lens array 52, and a weight 54 (see Figure 1 ). The light emitting device 50a is provided with a frame 60, a light emitting substrate 56, and a suppression member 80. In the description of the exposure device 50, the frame 60, the light emitting substrate 56, the lens array 52, the suppression member 80, and the weight 54 are described in this order.

[0047] [Frame 60]

[0048] As shown in Figures 2-4 , the frame 60 is a resin member extending in the apparatus depth direction and having an upper surface portion and a lower surface portion in the apparatus depth direction and the apparatus width direction. The frame 60 has a side surface portion 60a in the apparatus depth direction and the apparatus up-down direction. The lower surface portion of the frame 60 is referred to as a lower surface portion 60b. In the frame 60, an upper-side recessed portion 62 is formed in a rectangular shape recessed in the upper surface portion of the frame 60 and having a bottom surface 62a in the apparatus depth direction and the apparatus width direction. Also, in the frame 60, a lower-side recessed portion 64 is formed in a rectangular shape recessed in the lower surface portion 60b of the frame 60 and having a bottom surface 64a in the apparatus depth direction and the apparatus width direction. Further, in the frame 60, a through-hole 66 is formed that penetrates between the bottom surface 62a of the upper-side recessed portion 62 and the bottom surface 64a of the lower-side recessed portion 64 in the apparatus up-down direction.

[0049] At both end portions of the upper surface portion of the frame 60 in the apparatus depth direction, a planar portion 68 facing upward is formed. The frame 60 contacts the positioning member 90 of the photoreceptor unit 18 by the planar portion 68, and positions the position of the exposure device 50 in the apparatus up-down direction with respect to the photosensitive drum 36. The planar portion 68 is an example of a positioning portion.

[0050] Parts of both ends of the lower surface portion 60b of the frame 60 in the device depth direction contact the end 86 of the suppression member 80, which will be described later. Furthermore, the lower surface portion 60b of the frame 60 is a portion that receives the force of the force-applying mechanism 94, which applies force to the frame 60 via the end 86 to bring the flat portion 68 of the frame 60 into contact with the positioning member 90 of the photosensitive unit 18. The lower surface portion 60b is an example of a force-applying portion.

[0051] like Figure 6 As shown in (A), a protrusion 70 is formed at one end (in the -D direction) of the lower surface portion 60b of the frame 60 in the device depth direction, protruding downward from the lower surface portion 60b. Furthermore, as... Figure 7 As shown in (A), a protrusion 72 protruding downward from the lower surface portion 60b is formed at the other end (+D direction) of the lower surface portion 60b in the device depth direction of the frame 60. Figure 3 and Figure 6 As shown, the protrusion 70 has a hemispherical shape. (As indicated...) Figure 7 As shown, the protrusion 72 has a semi-circular shape when viewed from the width direction of the device, and extends along the width direction of the device. (As shown...) Figure 1 As shown, protrusions 70 and 72 are respectively formed on a portion of the lower surface portion 60b of the frame 60, which overlaps with the planar portion 68 of the frame 60 in the vertical direction when viewed from the width direction of the device.

[0052] The protrusions 70 and 72 on the lower surface portion 60b of the frame 60 respectively contact the respective ends 86 of the suppressing member 80. As described above, the protrusion 70 has a hemispherical shape, thereby making point contact with the end 86 of the suppressing member 80. As described above, the protrusion 72 has a shape that extends along the width direction of the device and is semi-circular when viewed from the width direction of the device, thereby making line contact with the end 86 of the suppressing member 80 along the width direction of the device. The protrusions 70 and 72 are examples of contact portions.

[0053] [Light-emitting substrate 56]

[0054] like Figure 2 As shown, the light-emitting substrate 56 includes a substrate body 56a and a plurality of (for example, 30) LED arrays 56b.

[0055] The substrate body 56a is a rectangular plate extending along the depth direction of the device with its thickness along the vertical direction. The lengths of the substrate body 56a in both the device depth and width directions are shorter than the lengths of the lower recess 64 of the frame 60 in both the device depth and width directions, but longer than the lengths of the through hole 66 in both the device depth and width directions. For example... Figure 3 and Figure 4As shown, the substrate body 56a is in contact with the bottom surface 64a of the lower recess 64 in such a way that it covers the through hole 66 from below, and is fixed to the frame 60 by an adhesive or the like.

[0056] like Figure 2 As shown, the LED array 56b consists of a plurality of LEDs arranged in a staggered pattern on the upper surface of the substrate body 56a and emitting light upwards. Here, LED stands for Light Emitting Diode. The light-emitting substrate 56 with the LED array 56b is an example of a light-emitting unit. The light-emitting substrate 56 heats up as the LED array 56b emits light (irradiates).

[0057] <Lens Array 52>

[0058] like Figure 2 As shown, the lens array 52 is a cuboid component extending along the depth direction of the device. Specifically, the lens array 52 is constructed by arranging a plurality of rod-shaped lenses (cylindrical lenses) with the vertical direction of the device as the optical axis in an alternating manner along the depth direction of the device, clamping them between two plate components, and bonding them with an adhesive or the like. The length of the lens array 52 in the device depth direction is shorter than the length of the upper recess 62 of the frame 60 in the device depth direction, but longer than the length of the through hole 66 in the device depth direction. Furthermore, the height of the lens array 52 in the device vertical direction is greater than the depth of the upper recess 62 in the device vertical direction. Figure 3 and Figure 4 As shown, when viewed from the depth direction of the device, a portion of the upper surface of the lens array 52 protrudes from the upper recess 62, and the lower surface of the lens array 52 is positioned in the upper recess 62 such that it covers the through hole 66 from above. In this state, the lens array 52 is fixed to the frame 60 by an adhesive or the like. Furthermore, a sealant 58 is filled throughout the circumference of the lens array 52 in the gap between the upper recess 62 and the lens array 52.

[0059] The lens array 52 is configured such that each LED of the LED array 56b is positioned opposite each rod-shaped lens of the lens array 52 at a predetermined position. Furthermore, the lens array 52 is configured such that when the planar portion 68 of the frame 60 contacts the positioning member 90 of the photosensitive unit 18, the upper surface of the lens array 52 is positioned opposite the photosensitive drum 36. Thus, the exposure apparatus 50 can image (expose) light emitted from the LED array 56b and transmitted through the lens array 52 at a predetermined target position on the surface of the photosensitive drum 36. The lens array 52 is an example of an optical component. The photosensitive drum 36 is an example of an exposure object. The exposure apparatus 50 has the function of forming an electrostatic latent image on the photosensitive drum 36 by imagerizing light emitted from the LED array 56b onto the charged photosensitive drum 36.

[0060] <Suppression Component 80>

[0061] like Figure 2 As shown, the suppressing component 80 is a component formed of a metal plate that extends along the depth direction of the device. For example... Figures 1-5 As shown, the suppressing member 80 is fixed to the frame 60 by covering the lower recess 64 of the frame 60 from below. The suppressing member 80 has a main body portion 82, a bent portion 84, and an end portion 86.

[0062] like Figures 2-4 As shown, the main body 82 is a portion having a U-shaped cross-section that opens upwards when viewed from the depth direction of the device and extends along the depth direction of the device. The pair of sidewalls and the bottom of the U-shaped cross-section of the main body 82 are referred to as sidewall 82a and bottom 82b, respectively. Figure 3 and Figure 4 As shown, the suppressing member 80 is configured such that the bottom 82b of the main body 82 is away from the lower surface of the frame 60 and a pair of side walls 82a clamp the side surface 60a of the frame 60.

[0063] like Figure 1 and Figure 2 As shown, on a pair of sidewalls 82a, at the locations where they overlap with the sidewalls 60a of the frame 60 in the width direction of the device, a plurality of through holes 82c are formed, arranged in the depth direction of the device and penetrating the sidewalls 82a in the thickness direction. The suppressing member 80 is fixed to the frame 60 by an adhesive or the like injected into and cured into the through holes 82c of the pair of sidewalls 82a of the sidewalls 60a of the frame 60.

[0064] The bending portions 84 are located at both ends of the bottom 82b in the device depth direction and have an L-shaped cross-section extending in both the vertical and depth directions when viewed from the device width direction, and are rectangular when viewed from the device depth direction. The bending portions 84 have feet 84a that stand upright in the vertical direction and a bottom 84b extending from the lower end of the feet 84a in the device depth direction. The bottom 84b of the bending portions 84 is connected to the bottom 82b of the main body 82. In other words, the two bending portions 84 are configured to clamp the main body 82 in the device depth direction. Furthermore, the feet 84a of the bending portions 84 are located away from the lower surface of the frame 60. Also, the feet 84a of the bending portions 84 are located between the protrusions 70 and 72 of the frame 60 in the device depth direction.

[0065] The end portion 86 is formed as a rectangular portion extending from the upper end of the foot portion 84a in the direction of device depth and device width, opposite to the main body portion 82, when viewed from the vertical direction of the device. The suppressing member 80 is fixed to the frame 60 with the upper surface of each end portion 86 in contact with the protrusions 70 and 72 of the frame 60. Furthermore, each end portion 86 overlaps with each planar portion 68 of the frame 60 in the vertical direction of the device when viewed from the width direction of the device.

[0066] The suppressing member 80 is fixed to the frame 60 by clamping the side portion 60a of the frame 60 with the main body 82. Compared with the frame 60 alone, it has the function of making the frame 60, which extends along the depth direction of the device, less prone to bending in the vertical direction of the device. That is, the suppressing member 80 has the function of suppressing the deformation of the frame 60.

[0067] like Figure 1 , Figure 3 , Figure 4 As shown, the balance weight 54 is a cuboid extending along the depth direction of the device and fixed to the bottom 82b of the suppression member 80 on the side opposite to the frame 60. By being provided in the exposure device 50, the balance weight 54 reduces the inherent vibration frequency of the exposure device 50 compared to a device without the balance weight 54. This causes the inherent vibration frequency of the exposure device 50 to deviate from the frequency of vibrations generated inside the image forming apparatus 10.

[0068] {Positioning component 90}

[0069] The positioning member 90 is a component disposed on a frame (not shown) of the image forming apparatus 10 and positioned above the flat portion 68 of the frame 60. The positioning member 90 is located at a predetermined position in the vertical direction relative to the photosensitive drum 36 and has a downward-facing contact surface 92. The positioning member 90 functions to position the exposure apparatus 50 relative to the photosensitive drum 36 in the vertical direction by contacting the flat portion 68 of the frame 60 with the contact surface 92.

[0070] {Force-Applying Mechanism 94}

[0071] The urging mechanism 94 is a mechanism configured, for example, by a compression spring, which is provided to a frame (not shown) of the image forming apparatus 10 and is arranged below the end portion 86 of each of the suppression members 80 and urges the end portion 86 upward. The urging mechanism 94 has a contact surface 98 that contacts the lower surface of each of the end portions 86. The urging mechanism 94 urges the end portion 86 upward by contacting the end portion 86 of the suppression member 80 fixed to the frame body 60, and has a function of urging the lower surface portion 60b of the frame body 60 via the end portion 86 so that the flat surface portion 68 contacts the contact surface 92 of the positioning member 90. In other words, the end portion 86 of the suppression member 80 is sandwiched between the lower surface portion 60b of the frame body 60 and the urging mechanism 94. Specifically, the end portion 86 of the suppression member 80 is sandwiched between the protruding portion 70 and the protruding portion 72 of the frame body 60 and the urging mechanism 94. That is, the end portion 86 of at least one of the suppression members 80 in the device depth direction is sandwiched between the lower surface portion 60b of the frame body 60 and the urging mechanism 94.

[0072] (Action and Effect)

[0073] Next, the action and effect of the embodiment will be described. In this description, in the case of describing the comparative embodiment with respect to the embodiment, when the same components and the like as those of the image forming apparatus 10 of the embodiment are used, the symbols and names of the components and the like are directly used for the description.

[0074] The light emitting apparatus 50a of the embodiment has a structure in which the end portion 86 of at least one of the suppression members 80 in the device depth direction is sandwiched between the lower surface portion 60b of the frame body 60 and the urging mechanism 94. The light emitting apparatus 50a of the comparative embodiment is compared with the light emitting apparatus of the comparative embodiment shown below.

[0075] The light emitting apparatus of the comparative embodiment has the suppression member composed only of the main body portion 82 instead of the suppression member 80. In other words, the suppression member of the comparative embodiment does not have the bent portion 84 and the end portion 86. Further, the lower surface portion 60b of the frame body 60 of the light emitting apparatus of the comparative embodiment contacts the urging mechanism 94, and is directly urged upward by the urging mechanism 94. In other words, the light emitting apparatus of the comparative embodiment is fixed to the frame body 60 in a state in which the suppression member is not urged by the urging mechanism 94. That is, the light emitting apparatus of the comparative embodiment causes only the frame body 60 to bear the load caused by the self-weight of the suppression member. With respect to the above aspects, the light emitting apparatus of the comparative embodiment is configured to have the same structure as the light emitting apparatus 50a of the embodiment.

[0076] The suppression member provided in the light emitting device suppresses the frame 60 from being bent in the up-and-down direction of the device by being fixed to the frame 60, and has a function of suppressing the frame 60 from being bent in the up-and-down direction of the device compared to the frame 60 alone. However, the suppression member fixed to the frame 60 can cause the frame 60 to be deformed outside the range in which the main body portion 82 is fixed, because the frame 60 bears the load caused by the weight of the suppression member.

[0077] On the other hand, in the light emitting device 50a of the embodiment, at least one end portion 86 of the suppression member 80 is sandwiched between the lower surface portion 60b of the frame 60 and the force applying mechanism 94, and the suppression member 80 is pressed by the force applying mechanism 94. That is, in the light emitting device 50a of the embodiment, the frame 60 and the force applying mechanism 94 share and bear the load caused by the weight of the suppression member. Therefore, in the light emitting device 50a of the embodiment, in which the suppression member 80 is fixed in the frame 60, deformation of the frame 60 caused by the weight of the suppression member 80 is suppressed compared to a structure in which the lower surface portion 60b of the frame 60 directly receives the force from the force applying mechanism 94.

[0078] Further, the light emitting device 50a of the embodiment has a structure in which both end portions 86 of the suppression member 80 on both sides in the device depth direction are sandwiched between the lower surface portion 60b of the frame 60 and the force applying mechanism 94. Therefore, in the light emitting device 50a of the embodiment, deformation of the frame 60 caused by the weight of the suppression member 80 is suppressed compared to a structure in which only one end portion 86 of the suppression member 80 is sandwiched between the lower surface portion 60b of the frame 60 and the force applying mechanism 94.

[0079] Further, the light emitting device 50a of the embodiment has a structure in which the main body portion 82 and the bent portion 84 of the suppression member 80 are away from the lower surface portion 60b of the frame 60.

[0080] The suppression member 80 fixed to the frame 60 of the light emitting device 50a is thermally deformed due to heat generated along with light emission of the light emitting substrate 56 of the light emitting device 50a. The frame 60 in which the suppression member 80 is fixed can be deformed along with the thermal deformation of the suppression member 80.

[0081] In the structure in which the suppression member 80 is fixed in the housing 60 of the light emitting device 50a, the main body portion 82 and the bent portion 84 of the suppression member 80 of the embodiment are distanced from the lower surface portion 60b of the housing 60. In other words, the light emitting device 50a of the embodiment has a structure in which the portion between the end portions 86 of the suppression member 80 on both sides is distanced from the lower surface of the housing 60. That is, the light emitting device 50a of the embodiment has a smaller contact area of the suppression member 80 with the housing 60 than a structure in which the entire suppression member is in contact with the lower surface of the housing 60 in the device up-down direction. Therefore, the light emitting device 50a of the embodiment has a smaller deformation of the housing 60 accompanying the deformation of the suppression member 80 than a structure in which the entire suppression member is in contact with the lower surface of the housing 60 in the device up-down direction.

[0082] Also, the light emitting device 50a of the embodiment has a structure in which the protruding portion 70 and the protruding portion 72 that are in point contact or line contact with the end portion 86 of the suppression member 80 are formed in the lower surface portion 60b of the housing 60. In other words, the light emitting device 50a of the embodiment has a contact portion that is in point contact or line contact with the other of the end portion 86 of the suppression member 80 or the lower surface portion 60b of the housing 60 at either of the end portion 86 of the suppression member 80 or the lower surface portion 60b of the housing 60. That is, the light emitting device 50a of the embodiment has a smaller contact area of the suppression member 80 with the housing 60 than a structure in which the end portion 86 of the suppression member 80 is in surface contact with the lower surface portion 60b of the housing 60. Therefore, the light emitting device 50a of the embodiment has a smaller deformation of the housing 60 accompanying the deformation of the suppression member 80 than a structure in which the end portion 86 of the suppression member 80 is in surface contact with the lower surface portion 60b of the housing 60.

[0083] Also, the light emitting device 50a of the embodiment has a structure in which the protruding portion 72 of the housing 60 is in line contact with one of the end portions 86 of the suppression member 80 in the device width direction. In other words, in the light emitting device 50a of the embodiment, at least one contact portion that either of the end portion 86 of the suppression member 80 or the lower surface portion 60b of the housing 60 has is in line contact with the other of the end portion 86 and the lower surface portion 60b in the device width direction. Therefore, the light emitting device 50a of the embodiment has a stable posture of the light emitting device 50a to which the force applying mechanism 94 applies a force via the suppression member 80 than a structure in which the end portions 86 on both sides are in point contact with the lower surface portion 60b.

[0084] Also, the light emitting device 50a of the embodiment has a structure in which the protruding portion 70 and the protruding portion 72 are provided to the housing 60. Therefore, the light emitting device 50a of the embodiment is easily formed than a structure in which a contact portion that is in point contact or line contact with the lower surface portion 60b of the housing 60 is provided to the suppression member 80.

[0085] Further, the exposure apparatus 50 provided with the light emitting device 50a of the embodiment is configured such that the frame 60 of the light emitting device provided to the exposure apparatus directly receives the force from the force applying mechanism 94 at the lower surface portion 60b, and compared to a configuration in which the frame 60 of the light emitting device provided to the exposure apparatus directly receives the force from the force applying mechanism 94 at the lower surface portion 60b, exposure failure is suppressed.

[0086] Further, the image forming apparatus 10 provided with the exposure apparatus 50 of the embodiment is configured such that the frame 60 of the light emitting device provided to the exposure apparatus directly receives the force from the force applying mechanism 94 at the lower surface portion 60b, and compared to a configuration in which the frame 60 of the light emitting device provided to the exposure apparatus directly receives the force from the force applying mechanism 94 at the lower surface portion 60b, image forming failure is suppressed.

[0087] As described above, the specific embodiments of the present application have been described in detail, but the present application is not limited to the above-described embodiments, and various modifications, changes, and improvements can be made within the scope of the technical idea of the present application.

[0088] For example, the light emitting device 50a of the embodiment is configured such that the end portions 86 of the suppression member 80 on both sides in the device depth direction are sandwiched between the lower surface portion 60b of the frame 60 and the force applying mechanism 94. However, the light emitting device according to the present application can also have a configuration in which only one end portion 86 in the device depth direction is sandwiched between the lower surface portion 60b of the frame 60 and the force applying mechanism 94.

[0089] Further, the light emitting device 50a of the embodiment is configured such that the portion between the end portions 86 of the suppression member 80 on both sides is away from the lower surface portion 60b of the frame 60. However, the light emitting device according to the present application can also have a configuration in which the entire suppression member is prevented from contacting the lower surface of the frame 60 in the device up-down direction, as long as at least one end portion 86 in the device depth direction is sandwiched between the lower surface portion 60b of the frame 60 and the force applying mechanism 94.

[0090] Further, the light emitting device 50a of the embodiment is configured such that either the end portion 86 of the suppression member 80 or the lower surface portion 60b of the frame 60 is in point contact or line contact with the other. However, the light emitting device according to the present application can also have a configuration in which the end portion 86 of the suppression member 80 is prevented from being in surface contact with the lower surface portion 60b of the frame 60, as long as at least one end portion 86 in the device depth direction is sandwiched between the lower surface portion 60b of the frame 60 and the force applying mechanism 94. In this case, the frame 60 can also not have a protruding portion that contacts the end portion 86 of the suppression member 80 at the lower surface portion 60b.

[0091] Moreover, the light emitting device 50a of the embodiment is configured such that the contact portion in which either the end portion 86 of the suppression member 80 or the lower surface portion 60b of the frame 60 is in point contact or line contact with the other of the end portion 86 or the lower surface portion 60b is a structure in which the protrusion 70 and the protrusion 72 are formed in the frame 60. However, the contact portion according to the present application can be formed in the suppression member 80.

[0092] Moreover, the light emitting device 50a of the embodiment is configured such that the protrusion 70 in which the end portion 86 of the suppression member 80 is in point contact with the lower surface portion 60b of the frame 60 and the protrusion 72 in which the end portion 86 is in line contact with the lower surface portion 60b are formed. However, the light emitting device according to the present application can have a structure in which only either the protrusion 70 or the protrusion 72 is provided. Moreover, the light emitting device according to the present application can have a structure in which, instead of the protrusion 72, a plurality of protrusions 70 are formed in the device width direction. Moreover, the light emitting device according to the present application can have a structure in which, instead of the protrusion 70, a protrusion in line contact with the end portion 86 in the device depth direction is formed. In addition, in a structure in which the protrusion 70 is formed on each of both sides of the frame 60 in the device width direction, when only one protrusion 70 is formed on one side, a plurality of protrusions 70 having different positions in the device width direction are preferably formed on the other side, for example.

[0093] Moreover, the light emitting device 50a of the embodiment is configured such that the end portion 86 of the suppression member 80 is in line contact with the lower surface portion 60b of the frame 60 in the protrusion 72 in the device width direction. However, the light emitting device according to the present application can have a structure in which the end portion 86 of the suppression member 80 is in line contact with the lower surface portion 60b of the frame 60 in the device depth direction. Moreover, the light emitting device according to the present application can have a structure in which both end portions 86 of the suppression member 80 are in line contact with both end portions of the lower surface portion 60b of the frame 60 in the device depth direction. In addition, when protrusions in contact with the end portion 86 of the suppression member 80 in the device depth direction are formed on both ends of the frame 60 in the device width direction, the protrusions are preferably staggered with each other in the device width direction, for example. Moreover, when protrusions in line contact with the end portion 86 of the suppression member 80 are formed on both ends of the frame 60 in the device width direction, the protrusions are preferably intersected with each other along the imaginary straight lines in the respective long side directions, for example.

[0094] Moreover, the light emitting device 50a of the embodiment is configured as a structure of an exposure device 50 that forms an electrostatic latent image by causing light to be imaged on a charged photosensitive drum 36. However, the light emitting device according to the present application is not limited to being provided in an exposure device. For example, the light emitting device according to the present application can be provided in a reading device (for example, a Contact Image Sensor: CIS).

[0095] Further, the light emitting device 50a of the embodiment is configured to be pressed from below by the pressing mechanism 94 and emit light upward. However, the light emitting device according to the present application can also have a configuration in which it is pressed from above by the pressing mechanism and emits light downward in the direction of pressing by the pressing mechanism. Further, the light emitting device according to the present application can also have a configuration in which it is pressed by the pressing mechanism in a tilted direction inclined in the vertical direction and emits light in the tilted direction in the direction of pressing by the pressing mechanism.

[0096] Further, the light emitting device 50a of the embodiment is configured such that a portion of the lower surface portion 60b of the frame 60 in which the protrusion 70 and the protrusion 72 are formed overlaps the planar portion 68 of the frame 60 in contact with the positioning member 90 in the device vertical direction as viewed in the device width direction. That is, the light emitting device according to the present application can also have a configuration in which the frame 60 is in contact with the positioning member 90 through a plurality of contact surfaces that do not overlap the protrusion 70 or the protrusion 72 in the device vertical direction as viewed in the device depth direction. In this case, the frame 60 according to the present application is preferably, for example, overlapped with the protrusion 70 or the protrusion 72 with respect to a center line extending in the device vertical direction with respect to the plurality of contact surfaces with the positioning member 90 as viewed in the device depth direction.

[0097] The above-described embodiments of the present application are provided for the purpose of illustration and explanation. In addition, the embodiments of the present application do not comprehensively and exhaustively include the present application, and do not limit the present application to the disclosed modes. It is obvious to those skilled in the art to which the present application pertains that various modifications and changes are self-evident. The present embodiments are selected and described in order to most easily explain the principles of the present application and its application. Thus, other skilled persons in the art can understand the present application through various modifications to the specific use assumed to be optimized for various embodiments. The scope of the present application is defined by the above claims and their equivalents.

Claims

1. A light emitting device comprising: a frame that is a resin frame extending in a direction and holding a light emitting portion that emits light upward in a height direction intersecting the direction, and that has a positioned portion that contacts a positioning member in the height direction and a forced portion that receives a force from a force applying mechanism that applies a force to the frame in a manner that the positioned portion contacts the positioning member on an upper side and a lower side of both end portions in the direction, respectively; and a restraining member that extends in the direction and is fixed to the frame and restrains the frame from deforming, and that sandwiches at least one end portion in the direction between the forced portion and the force applying mechanism, either of the end portion and the forced portion has a contact portion that point-contacts or line-contacts the other of the end portion and the forced portion.

2. The light emitting device according to claim 1, wherein both end portions in the direction of the restraining member are sandwiched between the forced portion and the force applying mechanism.

3. The light emitting device according to claim 2, wherein a portion between the end portions in the direction of the restraining member is away from a lower surface of the frame.

4. The light emitting device according to claim 1, wherein both end portions in the direction of the restraining member are sandwiched between the forced portion and the force applying mechanism, and a portion between the end portions in the direction is away from a lower surface of the frame, at least one contact portion line-contacts the other of the end portion and the forced portion in a direction intersecting the direction and the height direction.

5. The light emitting device according to claim 1 or 4, wherein the contact portion is provided to the frame.

6. An exposure device comprising: the light emitting device according to any one of claims 1 to 5; and an optical member that exposes light emitted from the light emitting device to an exposure object.

7. An image forming apparatus comprising: an image holding body; the exposure device according to claim 6 that forms an electrostatic latent image by imaging light on a charged image holding body; a positioning member that positions a position of the exposure device in the height direction with respect to the image holding body by contacting the positioned portion; a force applying mechanism that applies a force to the frame via the end portion in a manner that the positioned portion contacts the positioning member; and a developing device that develops the electrostatic latent image of the image holding body to form an image. ​ ​

Images