JP2011023869A - Image reading apparatus, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image reading apparatus and an image forming apparatus wherein heat produced by a light source can be dissipated. <P>SOLUTION: A shape of a plane part 57B of a bracket 57 is determined so that a projection part 86 where a light emitting elements 61 is projected on one surface 59B of the circuit board 59 may be supported by the plane part 57B in a state wherein the circuit board 59 is supported by the bracket 57. Namely, heat emitted by the light emitting elements 61 toward the circuit board 59 is not absorbed by the circuit board 59 more than necessary and is transmitted to the plane part 57B of the bracket 57 formed of a sheet metal member having a higher heat transfer rate than a resin member. That is, the heat produced by the light emitting element 61 is dissipated by the bracket 57. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image reading apparatus and an image forming apparatus.

  The image reading apparatus described in Patent Literature 1 includes an LED attached to a substrate and a light guide that guides light emitted from the LED. Specifically, the light emitted from the LED (point light source) enters the light guide from the incident surface of the light guide, and the light incident on the light guide is reflected inside the light guide to reflect the light from the light guide. It is guided to the exit surface.

JP 2005-252646 A

  In an image reading apparatus, in order to ensure reading accuracy, it is necessary to suppress fluctuations in the position and light amount of a light source that irradiates an image with light. However, when a plurality of light sources such as LEDs are arranged in a row on one surface of the substrate, there are problems that the substrate is deformed due to heat generation of the light source and the position of the light source varies, or the amount of light source varies.

  An object of the present invention is to dissipate heat generated by a light source.

  An image reading apparatus according to a first aspect of the present invention includes a plurality of light sources arranged in a row and emitting light, a substrate on which the plurality of light sources are attached to one surface, and another surface of the substrate. A support member that supports a projection portion on which the plurality of light sources are projected, and a reading unit that reads the light emitted from the plurality of light sources to the surface to be read and reflected from the surface to be read.

  The image forming apparatus according to claim 2 of the present invention is characterized in that the substrate and the support member are fixed at least at three locations.

  An image forming apparatus according to a third aspect of the present invention irradiates light on the surface of the image carrier based on the image reading apparatus according to the first or second aspect and image data read by the image reading apparatus. And an exposure device for forming a latent image.

  According to the image reading apparatus of the first aspect of the present invention, it is possible to dissipate the heat generated by the light source as compared with the case where the support member does not support the projected portion where the light source is projected onto the other surface of the substrate. .

  According to the image forming apparatus of the second aspect of the present invention, it is possible to suppress the deformation of the substrate even when a force for deforming the substrate is generated by the heat generated by the light source.

  According to the image forming apparatus of the third aspect of the present invention, an intended latent image can be formed on the surface of the image carrier as compared with the case where the image reading apparatus according to the first aspect is not provided.

FIG. 3 is a cross-sectional view of a first carriage of the image reading apparatus employed in the image forming apparatus according to the embodiment of the present invention. FIG. 3 is a cross-sectional view of a first carriage of the image reading apparatus employed in the image forming apparatus according to the embodiment of the present invention. FIG. 3 is a cross-sectional view of a first carriage of the image reading apparatus employed in the image forming apparatus according to the embodiment of the present invention. 1 is a perspective view illustrating a light emitting element, a circuit board, a bracket, and the like of an image reading apparatus employed in an image forming apparatus according to an embodiment of the present invention. 1 is an exploded perspective view showing a light emitting element, a circuit board, a bracket, and the like of an image reading apparatus employed in an image forming apparatus according to an embodiment of the present invention. 1 is a perspective view illustrating a light emitting element, a circuit base, a bracket, a light guide member, and the like of an image reading apparatus employed in an image forming apparatus according to an embodiment of the present invention. FIG. 3 is an exploded perspective view showing a first carriage of the image reading apparatus employed in the image forming apparatus according to the embodiment of the present invention. FIG. 3 is a perspective view illustrating a first carriage of the image reading apparatus employed in the image forming apparatus according to the exemplary embodiment of the present invention. 1 is a configuration diagram illustrating an image reading apparatus and an automatic document feeder that are employed in an image forming apparatus according to an embodiment of the present invention. 1 is a configuration diagram illustrating an image forming unit employed in an image forming apparatus according to an embodiment of the present invention. 1 is a schematic configuration diagram illustrating an image forming apparatus according to an embodiment of the present invention.

  An example of an image forming apparatus according to an embodiment of the present invention will be described with reference to FIGS.

(overall structure)
As shown in FIG. 11, on the upper part of the apparatus main body 10A of the image forming apparatus 10 according to the present embodiment, an automatic document feeder 12 that automatically conveys a plurality of read documents G one by one, and one sheet A first platen glass 16 on which the read document G is placed, and a document reading device 14 that reads the read document G conveyed by the automatic document feeder 12 or the read document G placed on the first platen glass 16 are provided. . In the figure, the arrow UP indicates the upper side in the vertical direction.

  As shown in FIG. 9, the automatic document feeder 12 includes a document table 13 on which a plurality of scanned documents G are placed on the upper surface, a delivery roll 15 that feeds the scanned documents G from the document table 13 one by one, and a delivery roll. And a first transporting roll 17 that transports the read original G sent out by 15.

  The automatic document feeder 12 also includes a first conveyance path 19 through which the read document G sent from the document table 13 is conveyed. The first transport path 19 includes a second transport roll 21 that transports the read original G downstream in the transport direction of the read original G, and a third transport roll that transports the read original G further downstream in the transport direction. 23, a position adjustment roll 25 that transports the read original G while adjusting the leading edge position (registration adjustment) of the read original G with respect to the original reading apparatus 14 after being stopped once, and the read original being read An auxiliary roll 27 that assists the conveyance of G and a fourth conveyance roll 29 that conveys the read read original G further downstream in the conveyance direction are provided. The first transport path 19 is provided with a guide member for guiding the read original G to be transported, but the illustration is omitted.

  Further, a second conveyance path 31 is provided on the downstream side in the conveyance direction of the fourth conveyance roller 29, and the read original G that has been read is discharged on the downstream side in the conveyance direction of the second conveyance path 31. A discharge roll 35 for discharging to the section 33 is provided.

  In addition, a third conveyance path 37 into which the read original G conveyed by reversing the discharge roll 35 is fed is provided between the discharge roll 35 and the third conveyance roll 23. Then, by transporting the read original G along the third transport path 37, the read original G whose front and back sides are reversed is transported along the first transport path 19 again. The document reading device 14 that reads the surface to be read of the read document G conveyed along the first conveyance path 19 will be described in detail later.

  On the other hand, as shown in FIG. 11, a plurality of toner images of different colors are formed in the central portion of the apparatus main body 10A in the vertical direction, and a plurality of toner images arranged side by side with respect to the horizontal direction are arranged. An image forming unit 30 is provided. Further, on the upper side of the image forming unit 30, an endless intermediate transfer belt 32 to which the toner image formed by the image forming unit 30 of each color is transferred while being circulated in the direction of arrow A in the drawing is provided.

  As the image forming unit 30, four image forming units 30Y, 30M, 30C, and 30K of yellow (Y), magenta (M), cyan (C), and black (K) are provided in this order. Then, the black (K) toner image transferred to the intermediate transfer belt 32 is finally located at the highest position in the image forming unit 30Y on which the yellow (Y) toner image transferred to the intermediate transfer belt 32 is formed first. Is formed at the lowest position, and the image forming units 30Y, 30M, 30C, and 30K are arranged at a certain interval in a slanting manner with respect to the horizontal direction as a whole. .

  These four image forming units 30Y, 30M, 30C, and 30K are basically configured similarly. In the following description, characters (Y, M, C, K) corresponding to each color are added to the code when distinguishing each color, and characters corresponding to each color are omitted unless otherwise distinguished.

  As shown in FIG. 10, the image forming unit 30 for each color is provided with an image carrier 34 that is rotated in the direction of arrow D by a driving means (not shown), and the surface of the image carrier 34 is uniformly charged. A charging member 36 for charging is provided.

  Further, on the downstream side in the rotation direction of the image carrier 34 with respect to the charging member 36, light corresponding to the determined color is exposed to the surface of the image carrier 34 whose surface is uniformly charged by the charging member 36. An exposure device 40 for forming an electrostatic latent image is provided. Further, on the downstream side in the rotation direction of the image carrier 34 with respect to the exposure device 40, a developing device that develops the electrostatic latent image formed on the surface of the image carrier 34 with toner of each color and visualizes it as a toner image. 42 is provided.

  Above the intermediate transfer belt 32, a toner cartridge 38Y that supplies toner of a predetermined color to the developing device 42 of each color of yellow (Y), magenta (M), cyan (C), and black (K). , 38M, 38C, and 38K (see FIG. 11). Since the toner cartridge 38K containing black (K) toner is used frequently, it is larger than other color toner cartridges.

  On the other hand, a primary transfer member 46 for transferring the toner image formed on the surface of the image carrier 34 to the intermediate transfer belt 32 is provided on the opposite side of the image carrier 34 with the intermediate transfer belt 32 interposed therebetween. . Further, a cleaning device 44 that cleans residual toner or the like remaining on the surface of the image carrier 34 without being transferred from the image carrier 34 to the intermediate transfer belt 32 is in contact with the surface of the image carrier 34, and is in contact with the primary transfer member 46. The image holding member 34 is provided on the downstream side in the rotation direction.

  With this configuration, as shown in FIGS. 10 and 11, yellow (Y), magenta (M), cyan (C), black (K) from the document reader 14 or externally when used as a printer. The image data of each color is sequentially output to the exposure devices 40Y, 40M, 40C, and 40K separately provided in the image forming units 30Y, 30M, 30C, and 30K of each color. Further, the light emitted from these exposure apparatuses 40Y, 40M, 40C, and 40K according to the image data exposes the surface of the image carrier 34 of each color charged by the charging member 36, and the surface of the image carrier 34 is exposed. An electrostatic latent image is formed. The electrostatic latent images formed on the surface of the image carrier 34 are respectively developed in yellow (Y), magenta (M), cyan (C), and black (K) by developing units 42Y, 42M, 42C, and 42K. Developed as a toner image.

  Further, yellow (Y), magenta (M), cyan (C), and black (K) toner images sequentially formed on the surface of the image carrier 34 are image forming units 30Y, 30M, and 30C for the respective colors. , The intermediate transfer belt 32 disposed at an angle above 30K is transferred in multiple by the primary transfer member 46.

  On the other hand, the intermediate transfer belt 32 includes a drive roll 48 that applies a driving force to the intermediate transfer belt 32, a support roll 50 that rotates following, a tension applying roll 54 that applies tension to the intermediate transfer belt 32, and a first roll. The idler roll 56 and the second idler roll 58 are wound around with a constant tension.

  Further, a cleaning device 52 for cleaning the surface of the intermediate transfer belt 32 is provided on the opposite side of the drive roll 48 across the intermediate transfer belt 32. This cleaning device 52 is provided on the front side of the apparatus main body 10A (a user stands up). By opening a front cover (not shown) provided on the front side), the apparatus main body 10A can be attached and detached.

  Further, on the opposite side of the support roll 50 across the intermediate transfer belt 32, a secondary transfer member 60 for secondary transfer of the toner image primarily transferred on the intermediate transfer belt 32 to a recording sheet P as a recording medium. Is arranged. That is, the secondary transfer position for transferring the toner image to the recording sheet P is between the secondary transfer member 60 and the support roll 50.

  A fixing device 64 is provided above the secondary transfer member 60 to fix the toner image on the recording sheet P to which the toner image is transferred by the secondary transfer member 60 and conveyed along the conveyance path 62. . The fixing device 64 includes a heating roll 64A disposed on the image surface side of the recording sheet P, and a pressure roll 64B that pressurizes the recording sheet P toward the heating roll 64A.

  Further, on the downstream side in the conveyance direction of the recording sheet P with respect to the fixing device 64 (hereinafter simply referred to as “the downstream side in the conveyance direction”), a conveyance roll 66 that conveys the recording sheet P on which the toner image is fixed is provided. A switching gate 68 for switching the conveyance direction of the recording sheet P is provided on the downstream side of the conveyance roll 66 in the conveyance direction.

  A first discharge roll 70 is provided on the downstream side of the switching gate 68 in the conveyance direction to discharge the recording sheet P guided by the switching gate 68 switched in one direction to the first discharge unit 69.

  Further, on the downstream side of the switching gate 68 in the transport direction, a second discharge roll that causes the second discharge section 72 to discharge the recording sheet P guided by the switch gate 68 switched in the other direction and transported by the transport roll 73. 74 and a third discharge roll 78 for discharging the recording sheet P to the third discharge portion 76 are provided.

  On the other hand, on the lower side of the apparatus main body 10A and upstream of the secondary transfer member 60 in the conveyance direction of the recording sheet P (hereinafter simply referred to as “upstream side in the conveyance direction”), the supply of the recording sheet P is accommodated. Paper sections 80, 82, 84, and 86 are provided, and recording sheets P having different sizes are accommodated in the paper feeding sections 80, 82, 84, and 86.

  Further, each of the paper feeding units 80, 82, 84, 86 is provided with a paper feeding roll 88 that takes the stored recording sheet P from the paper feeding units 80, 82, 84, 86 to the transport path 62. On the downstream side of the roll 88 in the conveyance direction, a conveyance roll 90 and a conveyance roll 92 that convey the recording sheets P one by one are provided.

  An alignment roll 94 that stops the recording sheet P at one end and sends it to the secondary transfer position at a predetermined timing is provided on the downstream side in the conveyance direction of the conveyance roll 92.

  On the other hand, in order to form images on both sides of the recording sheet P, a duplex conveying unit 98 that reverses and conveys the recording sheet P is provided on the side of the secondary transfer position. The double-sided conveyance unit 98 is provided with a reverse path 100 through which the recording sheet P conveyed by reversing the conveyance roll 73 is sent. Further, a plurality of transport rolls 102 are provided along the reversing path 100, and the recording sheet P transported by these transport rolls 102 is transported again to the alignment roll 94 with the front and back being reversed. It has become.

  Further, a foldable manual sheet feeding unit 106 is provided next to the duplex conveying unit 98. A paper feed roll 108 and transport rolls 110 and 112 for transporting the recording sheet P fed from the opened foldable manual sheet feeding unit 106 are provided and transported by the transport rolls 110 and 112. The recording sheet P is conveyed to the alignment roll 94.

(Main part configuration)
Next, the document reading device 14 provided below the automatic document feeder 12 will be described.

  As shown in FIG. 9, the first platen glass 16 on which the read original G is placed in a stationary state and the read original G conveyed by the automatic original conveyance device 12 are placed on the upper surface of the casing 41 of the original reading apparatus 14. And a second platen glass 43 for reading.

  In addition, the document reading device 14 includes a light emitting element 61 for reading an image on a surface to be read of the read original G, a first carriage 18 to which a light guide member 65 and the like are attached, and a light emitting element attached to the first carriage 18. And a second carriage 22 that guides the light emitted from 61 to the imaging unit 20 as an example of a reading unit.

  The first carriage 18 irradiates the surface to be read of the read document G with light L while being stationary under the second platen glass 43 which is the initial position or moving over the entire first platen glass 16. Thus, the light L reflected by the surface to be read is guided to the second carriage 22.

  On the other hand, the second carriage 22 reflects the light L incident from the first carriage 18 downward and the light L reflected by the second mirror 45A and reflects the light L reflected by the second mirror 45A. And a third mirror 45B that is folded back in a direction parallel to the second platen glass 43.

  The imaging unit 20 includes an imaging lens 24 that forms an image of the light L reflected by the third mirror 45B, a photoelectric conversion element 26 that photoelectrically converts an optical image formed by the imaging lens 24, and the like. It has. The electrical signal (image signal) converted by the photoelectric conversion element 26 is sent to an image processing device 28 that is electrically connected to the photoelectric conversion element 26. The image processing device 28 performs image processing on the received electrical signal and sends it to the control unit 71. The control unit 71 sends the received signal as image data to the exposure device 40 (see FIG. 11).

  Specifically, as shown in FIG. 8, the first carriage 18 includes two side plates 55A and 55B that are opposed to each other with a gap in the main scanning direction (arrow Y direction) and the main scanning direction in the longitudinal direction. The first holder 51 and the second holder 53 are formed from a sheet metal that is disposed at intervals in the sub-scanning direction (arrow X direction) and whose both ends are fixed to the side plates 55A and 55B.

  A third holder 47 and a fourth holder 49 are attached to the outside of the side plates 55A and 55B, respectively.

  Note that the upper surfaces of the first holder 51 and the second holder 53 constitute the upper surface of the first carriage 18 and are arranged to face the surface to be read of the read original G. Further, the distance in the main scanning direction between the side plates 55A and 55B is wider than the image forming area in the main scanning direction of the read original G (see FIG. 11).

  The first holder 51 has an L-shaped cut surface cut in the sub-scanning direction, and includes an upper wall 51A constituting the upper surface of the first carriage 18 and a side wall 51B in a direction intersecting the upper wall 51A. It has.

  Further, as shown in FIGS. 1 and 6, a bracket 57 as an example of a support member is provided on the inner side of the first holder 51 and is formed of a sheet metal member and extends in the main scanning direction. Then, on the side wall 51B side of the first holder 51 in the bracket 57, two side walls 57A are formed so as to overlap the side wall 51B, and the bracket 57 has a shape in which the lower part is opened.

  Further, a cut-and-raised claw 57C is provided on the side wall 57A of the bracket 57. Then, by sandwiching the side wall 51B of the first holder 51 between the claw 57C and the side wall 57A, the position of the bracket 57 relative to the first holder 51 in the sub-scanning direction (arrow X direction) is determined.

  Furthermore, a screw hole 112 in which a thread is cut and a protrusion 114 protruding toward the side wall 51B of the first holder 51 are formed in the side wall 57A of the bracket 57.

  As shown in FIGS. 2, 3, 7, and 8, the side wall 51 </ b> B of the first holder 51 is formed with a notch 116 that holds the protrusion 114. The notch 116 has an open end formed at the lower end of the side wall 51B and is bent toward one side in the longitudinal direction of the side wall 51B. Thereby, the protrusion 114 that has entered the notch 116 from the lower end of the side wall 51B is guided to the back side of the notch 116 on one side in the longitudinal direction of the side wall 51 (lower left side in FIG. 7). The protrusion 114 guided to the back side of the notch 116 is sandwiched and held by the inner wall of the notch 95 from above and below on the back side of the notch 116.

  On the other hand, as shown in FIGS. 1 and 6, a flat portion 57 </ b> B that is inclined with respect to the sub-scanning direction is provided on the opposite side of the side wall 57 </ b> A in the bracket 57. A circuit board 59 as an example of a board whose main scanning direction is the longitudinal direction is supported on the flat portion 57B. Further, on the circuit board 59, light emitting elements 61 as an example of point light sources arranged in a line along the main scanning direction are attached.

  Specifically, as shown in FIGS. 1 and 5, the light emitting element 61 is attached to one surface 59A of the circuit board 59, and the other surface 59B of the circuit board 59 is supported by the flat portion 57B. The circuit board 59 is provided with four through holes 96 at a predetermined interval in the longitudinal direction, and a screw hole 118 in which a thread is cut in the flat portion 57B corresponding to the through hole 96. Is provided. The circuit board 59 to which the light emitting element 61 is attached is fixed to the bracket 57 by tightening the four bolts 120 into the screw holes 118 through the through holes 96.

  As shown in FIG. 1 and FIG. 4, the projection unit 86 in which the light emitting element 61 is projected onto the other surface 59 </ b> B (back surface) of the circuit board 59 with the circuit board 59 fixed to the bracket 57 is bracketed. The shape of the flat surface portion 57B is determined so that the 57 flat surface portions 57B are supported.

  Further, the circuit board 59 is supplied with power from the control unit 71 (see FIG. 11) via the flexible board 63 (see FIG. 8) connected to the end.

  In this embodiment, an LED (Light Emitting Diode) element is used as the light emitting element 61. However, the present invention is not limited to this, and any element that emits light in a dot shape may be used. For example, another light emitting element such as an organic EL (Electro Luminescence) element or an inorganic EL element may be used.

  The control unit 71 (see FIG. 11) of the image forming apparatus 10 incorporates a light source driving circuit (not shown) for causing the light emitting element 61 to emit light (drive) through the circuit board 59. Further, the light source driving circuit includes a switch for switching light emission on and off for each light emitting element 61, and a resistor for adjusting the amount of light emitted from each light emitting element 61 to the read surface of the read original G. I have. Then, the light source driving circuit causes the light emitting element 61 to emit light (drive) based on a light source driving signal for controlling on / off of light emission of the light emitting element 61 and an adjustment signal for adjusting the amount of light. It has become.

  On the other hand, as shown in FIG. 1, a light guide member 65 whose longitudinal direction is the main scanning direction is provided in the first carriage 18 so as to face the light emission surface of the light emitting element 61. The light guide member 65 is formed by forming a transparent resin (for example, acrylic resin) into a rectangular parallelepiped shape, and a light incident surface 65A on which light emitted from the light emitting element 61 is incident, and light incident from the light incident surface 65A are received. And a light emitting surface 65B that emits light. Further, both end portions of the light guide member 65 in the main scanning direction are supported by side plates 55A and 55B (see FIG. 8). The light guide member 65 diffuses directional light at least in the main scanning direction and guides the light emitted from the light emitting element 61 to the vicinity of the surface to be read of the read original G (see FIG. 1). ing.

  Thereby, on the light emitting surface 65B of the light guide member 65, the light of the light emitting element 61 incident from the light incident surface 65A is totally reflected and emitted inside, and the variation in the light amount distribution on the light emitting surface 65B. Can be suppressed.

  Further, a light diffusing plate 67 is joined to the light emitting surface 65 </ b> B of the light guide member 65. On the surface of the diffusing plate 67, irregularities for diffusing the light emitted from the light emitting surface 65B of the light guide member 65 are formed.

  Further, at a position away from the diffusion plate 67 by a predetermined distance in the sub-scanning direction, a part of the light emitted from the diffusion plate 67 is reflected to the reading surface of the read original G (see FIG. 11). A reflecting plate 79 is disposed. The reflection plate 79 is a mirror body whose longitudinal direction is the main scanning direction, and a surface opposite to the reflection surface that reflects light is fixed to the second holder 53.

  Further, below the light guide member 65 and the diffusing plate 67, a first mirror 75 that guides the light reflected by the read surface of the read original G to the second mirror 45A (see FIG. 9) of the second carriage 22 is provided. Is provided. Note that both ends of the first mirror 75 are inserted and held in holes formed in the side plates 55A and 55B (see FIG. 8).

(Function)
With this configuration, as shown in FIGS. 1 and 9, the light L emitted from each light emitting element 61 proceeds while being totally reflected inside the light guide member 65 and is diffused by the diffusion plate 67. A part of the light L diffused by the diffusing plate 67 passes through the second platen glass 43 or the first platen glass 16 and is irradiated on the read surface of the read original G, and the rest of the light L is reflected by the reflecting plate. After being reflected at 79, the light passes through the second platen glass 43 or the first platen glass 16 and is irradiated onto the surface to be read of the read original G.

  As described above, the light emitting element 61 attached to the first carriage 18 irradiates the read surface of the read original G with the light L from the front and rear in the sub-scanning direction. Then, the light L irradiated to the surface to be read of the read original G is reflected by the surface to be read, then reflected by the first mirror 75, and from the second carriage 22 through the imaging lens 24 to the photoelectric conversion element. 26 is imaged.

  Here, when the surface to be read of the read original G placed on the first platen glass 16 is read, the first carriage 18 and the second carriage 22 move in the moving direction at a ratio of 2: 1 (see FIG. 9). In the direction of arrow E). At this time, the light L is irradiated from the first carriage 18 to the surface to be read of the read original G, and the light L reflected by the surface to be read is guided to the second carriage 22, and the second mirror 45A and the third mirror 45B. The light is sequentially reflected and guided to the imaging lens 24. The light L guided to the imaging lens 24 is imaged on the light receiving surface of the photoelectric conversion element 26. The movement distance of the second carriage 22 is half of the movement distance of the first carriage 18 so that the optical path length of the light L from the read surface of the read original G to the photoelectric conversion element 26 does not change. It has become.

  On the other hand, when reading the surface to be read of the read original G conveyed by the automatic original conveyance device 12, the first carriage 18 and the second carriage 22 are arranged at one end of the original reading device 14 (the left end in FIG. 9). It is in the state stopped at the solid line reading position shown. At this reading position, the light L is emitted through the second platen glass 43 through the second platen glass 43 from the light emitting element 61 attached to the first carriage 18 to the read surface of the read original G conveyed by the automatic original conveyance device 12. Then, the light L reflected by the surface to be read is guided to the second carriage 22.

  Specifically, the light L reflected by the first line of the surface to be read of the read original G that has been conveyed is imaged by the imaging lens 24 through the second carriage 22, and the image is read by the photoelectric conversion element 26. . That is, one line in the main scanning direction is simultaneously processed by the photoelectric conversion element 26 that is a one-dimensional sensor, and then the next line in the main scanning direction of the read original G to be conveyed is read. Then, when the rear end of the read original G passes through the reading position of the second platen glass 43, the reading of one page of the reading surface of the read original G is completed in the sub-scanning direction.

  Here, when the light emitting element 61 emits the light L, the light emitting element 61 releases heat, and this heat is transmitted to the circuit board 59. When heat is absorbed by the circuit board 59, the temperature of the circuit board 59 becomes higher than necessary, and the circuit board 59 may be deformed (warped).

  However, in the present embodiment, as described above, the projection portion 86 obtained by projecting the light emitting element 61 onto the other surface 59B of the circuit board 59 in a state where the circuit board 59 is supported by the bracket 57 is a flat portion of the bracket 57. The shape of the flat portion 57B is determined so that the 57B is supported. That is, the heat released to the circuit board 59 by the light emitting element 61 is not absorbed by the circuit board 59 more than necessary, and the plane of the bracket 57 formed of a sheet metal member having a higher heat transfer coefficient than the resin member. Is transmitted to the unit 57B.

  As described above, the heat released to the circuit board 59 by the light emitting element 61 is transmitted to the flat portion 57B of the bracket 57 without being absorbed more than necessary by the circuit board 59, so that the temperature of the circuit board 59 is more than necessary. It is suppressed that it becomes high.

  In addition, since the temperature of the circuit board 59 is suppressed from becoming higher than necessary, the circuit board 59 is prevented from being deformed (warped). That is, the heat generated by the light emitting element 61 is radiated by the bracket 57.

  Further, since the deformation of the circuit board 59 is suppressed, the amount of light applied to the read surface of the read original G by the light emitting element 61 becomes uniform, and an intended latent image is formed on the surface of the image carrier 34.

  Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to such embodiments, and various other embodiments are possible within the scope of the present invention. It is clear to the contractor. For example, in the above embodiment, heat is transmitted to the bracket 57 formed of the sheet metal member to suppress the temperature of the circuit board 59 from becoming higher than necessary, but the bracket is not particularly formed of the sheet metal member. Any member having a high thermal conductivity may be used. For example, a member formed of silicon or the like may be used. In this embodiment, the circuit board 59 and the bracket 57 are fixed with four bolts 120. However, even if the circuit board 59 expands due to heat, the adhesion to the bracket 57 may be maintained. It suffices that at least one location other than the portion is fixed.

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 14 Original reading apparatus 20 Image formation part (an example of reading means)
34 Image carrier 40 Exposure device 57 Bracket (an example of a support member)
59 Circuit board (an example of a board)
59A One surface 59B Other surface 61 Light emitting element (an example of a light source)
86 Projection part (projection part)

Claims (3)

A plurality of light sources arranged in rows and emitting light;
A substrate on which the plurality of light sources are mounted on one surface;
A support member for supporting a projected portion obtained by projecting the plurality of light sources on the other surface of the substrate;
Reading means for reading light emitted from the plurality of light sources to the reading surface and reflected from the reading surface;
An image reading apparatus comprising:   The image reading apparatus according to claim 1, wherein the substrate and the support member are fixed at least at three locations. The image reading apparatus according to claim 1 or 2,
An exposure device that forms a latent image by irradiating the surface of the image carrier with light based on image data read by the image reading device;
An image forming apparatus comprising:

Images