JP2017215497A - Optical scanner and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a miniaturized optical scanner.SOLUTION: An optical deflector 117 is fixed to an optical box 113 with fixing parts 133 and 134 provided in a substrate part 128 by using screws 137 and 138. At least one fixing part 133 of the fixing parts 133 and 134 includes a cylindrical part 133a that has a shaft part 137b of the screw 137 inserted therein and has a lower face 137a1 of a head part 137a of the screw 137 in contact with an axial direction end 133a2. The substrate part 128 is provided with an electric circuit part at a position closer to a lateral face 133a3 of the cylindrical part 133a than an outermost diameter D1 of the head part 137a of the screw 137. A top face 127b of the electric circuit part and the lower face 137a1 of the head part 137a of the screw 137 are separated from each other.SELECTED DRAWING: Figure 6

Description

  The present invention relates to an optical scanning device provided in an image forming apparatus such as a copying machine, a printer, or a facsimile machine.

  An optical scanning device used in an image forming apparatus optically modulates a laser beam emitted from a light source in accordance with an image signal, and deflects and scans the optically modulated laser beam with an optical deflector including a rotating polygon mirror. . The laser beam that has been deflected and scanned is optically scanned in a spot-like image on the surface of the photosensitive drum by a scanning lens such as an imaging optical system to record an image.

  The image forming apparatus is required to be downsized from the viewpoint of improving the degree of freedom of installation and reducing costs. Accordingly, there is a demand for downsizing the optical scanning device and shortening the relative distance between the surface of the photosensitive drum and the optical scanning device. In order to realize them, it is necessary to bring the scanning lens and the rotary polygon mirror close to each other.

  Here, the scanning lens is held by a holding portion provided in the casing, and the optical deflector needs to be provided to avoid interference with the holding portion. Therefore, when the area of the substrate portion of the optical deflector is large, it is difficult to bring the scanning lens and the rotary polygon mirror close to each other.

  The substrate portion of the optical deflector includes a base plate having a fixing portion for securing rigidity and fixing to the housing, and an electric circuit for controlling the rotation of the rotary polygon mirror. The electric circuit may be provided on a circuit board which is a separate member from the base plate, or may be provided directly on the base plate. The area of the substrate part of the optical deflector is greatly contributed by the area of the electric circuit and the area of the fixing part for fixing to the housing. In general, as described in Patent Document 1, for example, an optical deflector is fastened to a housing using a screw (screw) at a fixing portion of a base plate.

JP 2011-133817 A

  However, the electric circuit pattern has to be provided apart from the outermost diameter of the screw in order to avoid applying stress due to the fastening of the screw. That is, the electric circuit pattern cannot be arranged around the screw fixing portion of the base plate, and as a result, miniaturization of the substrate portion has been hindered.

  The present invention solves the above-described problems, and an object of the present invention is to provide a downsized optical scanning device.

  A typical configuration of the optical scanning device according to the present invention for achieving the above object includes a light source, a rotating polygon mirror that deflects and scans a light beam from the light source, a rotating member that supports the rotating polygon mirror, An optical deflector comprising: a shaft or a bearing for rotatably holding the rotating member; and an electric circuit unit for rotating the rotating member, and a substrate unit for holding the shaft or the bearing, and the optical deflection An optical scanning device having an optical box to which the optical device is fixed and a scanning lens for forming an image of a light beam deflected and scanned by the rotary polygon mirror on the surface to be scanned, wherein the optical deflector uses a screw Are fixed to the optical box via a fixing portion provided on the substrate portion, and at least one of the fixing portions includes a shaft portion of the screw inserted therein and a head portion of the screw. Cylinder whose lower surface is in contact with the axial end The board portion is provided with the electric circuit portion at a position closer to the side surface of the cylindrical portion than the outermost diameter of the screw head, and the top surface of the electric circuit portion and the top surface of the electric circuit portion It is characterized in that the lower surface of the head of the screw is separated.

  According to the present invention, the optical scanning device can be reduced in size.

1 is a cross-sectional explanatory diagram illustrating a configuration of an image forming apparatus including an optical scanning device according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory perspective view illustrating a configuration of a first embodiment of an optical scanning device according to the present invention. It is an isometric view explanatory drawing which shows the structure of the optical deflector of 1st Embodiment. It is a section explanatory view showing an internal configuration of an optical deflector of a 1st embodiment. It is a disassembled perspective view which shows a mode that the optical deflector of 1st Embodiment is assembled | attached to an optical box. It is a section explanatory view showing the composition around the fixed part in the state where the optical deflector of the 1st embodiment was assembled in the optical box. (A) is plane explanatory drawing which shows the structure of the fixing | fixed part of the optical deflector of 1st Embodiment. (B) is sectional explanatory drawing which shows the structure of the fixing | fixed part of the scanner motor of a comparative example. It is a perspective explanatory view showing the configuration of the optical deflector of the second embodiment of the optical scanning device according to the present invention. (A) is a plane explanatory view explaining the operation effect of a 2nd embodiment. (B) is plane explanatory drawing which compares the effect with 1st Embodiment. It is a perspective explanatory view showing the configuration of the optical deflector of the third embodiment of the optical scanning device according to the present invention.

  An embodiment of an image forming apparatus provided with an optical scanning device according to the present invention will be specifically described with reference to the drawings.

  First, the configuration of a first embodiment of an image forming apparatus including an optical scanning device according to the present invention will be described with reference to FIGS.

<Image forming apparatus>
First, the configuration of an image forming apparatus including an optical scanning device according to the present invention will be described with reference to FIG. FIG. 1 is an explanatory cross-sectional view illustrating a configuration of an image forming apparatus 101 including an optical scanning device according to the present embodiment. In FIG. 1, reference numeral 102 denotes an optical scanning device, which is installed on an optical bench 103 supported by an apparatus frame (not shown) of the main body of the image forming apparatus 101.

  The optical bench 103 is a part of the housing of the image forming apparatus 101. The image forming apparatus 101 is fed by a feeding unit 104 for placing a recording material P such as paper, a feeding roller 105 for feeding the recording material P placed on the feeding unit 104, and a feeding roller 105. A separation roller 1 for separating the recording material P to be fed one by one is provided. The recording material P separated and fed one by one by the cooperation of the feeding roller 105 and the separation roller 1 comes into contact with the nip portion of the registration roller 2 that has stopped once, and the recording material P is in the waist of the recording material P. Skew is corrected by strength.

  The image forming apparatus 101 is provided with an image forming unit including a process cartridge 108 provided with a photosensitive drum 109 serving as an image carrier. Further, a transfer roller 106 serving as a transfer unit is provided facing the photosensitive drum 109.

  The process cartridge 108 is provided with a charging roller 3 serving as a charging unit that uniformly charges the surface of the photosensitive drum 109 that rotates clockwise in FIG. On the surface (on the surface to be scanned) of the photosensitive drum 109 uniformly charged by the charging roller 3, a light beam L corresponding to image information is irradiated by the optical scanning device 102 to form an electrostatic latent image.

  The process cartridge 108 is further provided with a developing roller 4 serving as a developer carrying member for supplying the developer (toner) accommodated in the developing container to the surface of the photosensitive drum 109. Developer (toner) is supplied to the electrostatic latent image formed on the surface of the photosensitive drum 109 by the developing roller 4 and developed as a toner image.

  The recording material P is nipped and conveyed by the registration roller 2 in accordance with the timing at which the toner image formed on the surface of the photosensitive drum 109 reaches the transfer nip portion between the photosensitive drum 109 and the transfer roller 106, and is conveyed to the transfer nip portion. Is done. A transfer bias is applied to the transfer roller 106 from a transfer bias power source (not shown), and the toner image formed on the surface of the photosensitive drum 109 is transferred to the recording material P. Residual toner remaining on the surface of the photosensitive drum 109 after the transfer is scraped off and removed by a cleaning blade which is a cleaning unit (not shown).

  The recording material P to which the toner image has been transferred is conveyed to a fixing device 107 serving as a fixing unit, and is heated and pressed in the process of being nipped and conveyed by a fixing roller and a pressure roller provided in the fixing device 107. The toner image is melted by heat and fixed on the recording material P. The recording material P on which the toner image is thermally fixed is nipped and conveyed by the discharge roller 110 and is discharged onto a discharge tray 5 provided outside the image forming apparatus 101.

<Optical scanning device>
Next, the configuration of the optical scanning device 102 of the present embodiment will be described with reference to FIG. FIG. 2 is a perspective explanatory view showing the configuration of the optical scanning device 102 of the present embodiment. As shown in FIG. 2, the light beam L indicated by the one-dot chain line emitted from the light source device 111 (light source) is collected by the cylindrical lens 112 only in the sub-scanning direction (the circumferential direction of the photosensitive drum 109, the conveyance direction of the recording material P). Lighted.

  Thereafter, the beam is limited to a predetermined beam diameter by an optical aperture 114 formed of a through hole formed in an optical box 113 made of black resin or the like. Then, the light beam L from the light source device 111 (light source) is condensed into a long linear shape in the main scanning direction (axial direction of the photosensitive drum 109) on the reflection surface 116 of the rotary polygon mirror 115 that performs deflection scanning.

  The rotary polygon mirror 115 is rotationally driven by the optical deflector 117 and deflects the light beam L incident on the reflection surface 116. The deflected light beam L is collected on the surface of the photosensitive drum 109 after passing through a scanning lens 118 that forms an image of the light beam L deflected and scanned by the rotary polygon mirror 115 on the surface of the photosensitive drum 109 (on the surface to be scanned). Scanned with light. As a result, an electrostatic latent image corresponding to the image information is formed on the surface of the photosensitive drum 109 uniformly charged by the charging roller 3. The optical deflector 117 is fixed to the optical box 113. The upper opening of the optical box 113 is closed by an optical lid (not shown) made of resin or sheet metal.

<Optical deflector>
Next, the configuration of the optical deflector 117 of this embodiment will be described with reference to FIGS. 3 and 4. FIG. 3 is a perspective explanatory view showing the configuration of the optical deflector 117 provided in the optical scanning device 102 of the present embodiment. FIG. 4 is an explanatory cross-sectional view showing the configuration of the optical deflector 117 provided in the optical scanning device 102 of the present embodiment.

  As shown in FIG. 4, the rotary polygon mirror 115 is placed and supported on the upper surface of a rotor boss 123 serving as a rotating member. The rotor boss 123 is fixed by inserting a rotating shaft 121 (shaft) into a through hole 123a provided at the center. The rotating polygonal mirror 115 has a cylindrical portion 123b provided so as to protrude in the axial direction of the rotor boss 123 in a through hole 115a provided in the central portion. The rotary polygon mirror 115 placed on the upper surface of the rotor boss 123 is moved upward in FIG. 4 by an elastic member 124 such as a leaf spring fitted on a rotary shaft 121 (shaft) that rotatably holds the rotor boss 123 (rotary member). And is elastically fixed.

<Rotation drive source>
A motor serving as a driving source for rotating the rotary polygon mirror 115 includes a rotating shaft 121 and a bearing 122 that rotatably supports the rotating shaft 121. The bearing 122 is fixed to the base plate 126. A rotor 125 serving as a rotor is integrally formed on the rotor boss 123 by caulking or the like.

  Further, a circuit board 127 made of paper phenol or glass epoxy resin is fixed on a base plate 126 made of metal and having conductivity, thereby constituting a board portion 128. On the circuit board 127, an electric circuit unit for rotationally driving the rotor boss 123 (rotating member) is mounted.

  The substrate portion 128 is provided with a stator 131 serving as a stator having a stator core 129 and a stator coil 130. The substrate portion 128 holds the rotating shaft 121 through a bearing 122 so as to be rotatable. A rotor boss 123 is integrally formed at the upper end of the rotating shaft 121. As a result, when the current flows through the stator coil 130, the rotor 125, the rotor boss 123, the rotating shaft 121, the rotary polygon mirror 115, and the elastic member 124 rotate integrally.

<Board part>
Next, the configuration of the substrate unit 128 of the optical deflector 117, which is a characteristic configuration of the present embodiment, will be described with reference to FIG. As shown in FIG. 3, the board portion 128 of the present embodiment is provided with fixing portions 133 and 134, a step portion 135, and a caulking portion 136.

<Fixed part>
FIG. 5 is an exploded perspective view showing how the optical deflector 117 is assembled to the optical box 113. FIG. 6 is a cross-sectional explanatory view showing a configuration around the fixing portion 133 in a state where the optical deflector 117 is assembled to the optical box 113. As shown in FIGS. 5 and 6, the optical deflector 117 is provided on the bottom surface 113 a of the optical box 113 through fixing portions 133 and 134 provided on the substrate portion 128 using screws (screws) 137 and 138. Fastened to the fastening portions 139 and 140.

  As shown in FIG. 6, the one fixing portion 133 is configured to include a cylindrical portion 133 a that is formed by protruding from a metal base plate 126 having conductivity to the circuit board 127 side by drawing or the like. A through hole 133a1 that penetrates the base plate 126 is provided in the cylindrical portion 133a. As shown in FIG. 3, a U-shaped cutout portion 127a that can be fitted into the cylindrical portion 133a is provided at a position corresponding to the cylindrical portion 133a of the circuit board 127. The other fixing portion 134 is configured to have a through hole that penetrates the base plate 126.

  Note that the fixed portion 133 and the fixed portion 134 are provided at positions facing each other with the rotary polygon mirror 115 interposed therebetween. The step portion 135 is provided to narrow a part of the end portion of the substrate portion 128 in the direction of the arrow X in FIG. The caulking portion 136 is provided to electrically connect and ground the ground (ground) of the electric circuit portion provided on the circuit board 127 and the conductive base plate 126.

<Assembly>
As shown in FIG. 5, fastening portions 139 and 140 are provided on the bottom surface 113 a of the optical box 113. The optical deflector 117 is assembled to the optical box 113. At that time, as shown in FIG. 6, the shaft portion 137 b of the screw (screw) 137 is inserted into the through hole 133 a 1 formed in the cylindrical portion 133 a of the fixing portion 133. Then, the male screw portion 137b1 formed on the outer peripheral surface of the shaft portion 137b is screwed and fastened to the female screw portion 139a provided in the fastening portion 139.

  At that time, the lower surface 137a1 of the head portion 137a of the screw (screw) 137 contacts the axial end portion 133a2 of the cylindrical portion 133a. As a result, as shown in FIG. 6, the optical deflector 117 with the top surface 127 b of the electric circuit section provided on the circuit board 127 and the lower surface 137 a 1 of the head 137 a of the screw (screw) 137 separated by a gap C. Is fixed to the optical box 113.

  On the other hand, as shown in FIG. 5, a shaft portion 138 b of a screw (screw) 138 is inserted into a fixing portion 134 formed of a through hole provided through the base plate 126. Then, the male screw portion 138b1 formed on the outer peripheral surface of the shaft portion 138b is screwed and fastened to the female screw portion 140a provided in the fastening portion 140. At this time, the optical deflector 117 is fixed to the optical box 113 by the lower surface 138a1 of the head 138a of the screw (screw) 138 being in pressure contact with the peripheral portion of the fixing portion 134 formed of a through hole.

  As shown in FIG. 6, the shaft portion 137 b of the screw 137 is inserted into a through hole 133 a 1 formed inside the cylindrical portion 133 a of the fixed portion 133. The male screw portion 137b1 provided on the outer peripheral surface of the shaft portion 137b is screwed and fastened to the female screw portion 139a of the fastening portion 139 provided on the bottom surface 113a of the optical box 113.

  As shown in FIG. 6, the contact surface 139 b formed by the upper surface of the fastening portion 139 provided on the bottom surface 113 a of the optical box 113 is provided directly below the cylindrical portion 133 a of the fixed portion 133 provided on the optical deflector 117. ing. The cylindrical portion 133a of the fixed portion 133 is pressed in the direction of arrow Z1 in FIG. 6 with the lower surface 137a1 of the head portion 137a of the screw 137 coming into contact with the axial end portion 133a2 of the cylindrical portion 133a. Further, the cylindrical portion 133a of the fixed portion 133 is pressed in the direction of the arrow Z2 in FIG. 6 by the drag received from the contact surface 139b of the fastening portion 139 provided on the bottom surface 113a of the optical box 113. The arrow Z1 direction and the arrow Z2 direction in FIG. 6 are directed in opposite directions on the same action line 6.

  As shown in FIG. 6, the electric circuit portion on the circuit board 127 is provided at a position closer to the side surface 133a3 of the cylindrical portion 133a than the outermost diameter D1 of the head portion 137a of the screw 137. In the fixing part 133 shown in FIG. 6, the electric circuit part on the circuit board 127 is arranged at the following position. Arranged close to the side surface 133a3 of the cylindrical portion 133a up to the position of the corner portion 133b, which is a connecting portion between the flat portion 126a of the base plate 126 and the cylindrical portion 133a provided upright with respect to the flat portion 126a. Has been.

  As shown in FIG. 6, the width D2 of the notch 127a of the circuit board 127 fitted into the cylindrical portion 133a of the fixing portion 133 is smaller than the outermost diameter D1 of the head 137a of the screw 137. The width D2 of the cutout portion 127a corresponds to the circumferential diameter of the boundary portion 133b1 between the corner portion 133b of the fixing portion 133 and the flat portion 126a of the base plate 126. As a result, the electric circuit portion on the circuit board 127 can be provided up to a region on the inner side (closer to the side surface 133a3 of the cylindrical portion 133a) than the outermost diameter D1 of the head portion 137a of the screw 137.

<Effect>
Next, the effect of this embodiment is demonstrated using FIG. FIG. 7A is an explanatory plan view showing a configuration around the fixed portion 133 of the optical deflector 117. FIG. 7B is an explanatory plan view showing a configuration around the fixed portion of the scanner motor 7 serving as an optical deflector described in Patent Document 1 as a comparative example.

  In general, when the optical deflector 117 is fixed by the screw 137, the upper surface of the electric circuit portion formed of the electric circuit pattern formed on the circuit board 127 is not directly pressed. The reason is to prevent deterioration of electrical characteristics due to stress applied to the electrical circuit pattern. Furthermore, when the circuit board 127 made of paper phenol or glass epoxy resin is directly fastened by the screw 137, the screw 137 may be loosened due to the influence of moisture absorption or the like. Therefore, like the scanner motor 7 described in Patent Document 1 shown in FIG. 7B, the drive circuit board 21 is screwed by a notch 21a having a width D3 larger than the outermost diameter D1 of the head 11a of the screw 11. 11 was attached to the iron substrate 8 in a state of being separated from the head 11a.

  In the optical deflector 117 of the present embodiment, as shown in FIG. 6, the fixed portion 133 is configured by a cylindrical portion 133 a formed to protrude from the base plate 126 toward the circuit board 127 by drawing or the like. Thereby, the circuit board 127 can be provided to the inner side (closer to the side surface 133a3 of the cylindrical portion 133a) than the outermost diameter D1 of the head 137a of the screw 137.

  As a result, as shown in FIG. 7A, the width D2 of the cutout portion 127a of the circuit board 127 fitted to the cylindrical portion 133a of the fixing portion 133 is made smaller than the outermost diameter D1 of the head portion 137a of the screw 137. Can be set. Thereby, the optical deflector 117 can secure the area of the circuit board 127 around the fixed portion 133.

  For this reason, the area of the board | substrate part 128 can be made small compared with the drive circuit board | substrate 21 of the scanner motor 7 used as the optical deflector of the comparative example shown in FIG.7 (b). As a result, the cost of the optical deflector 117 can be reduced and the optical scanning device 102 can be downsized. Accordingly, by shortening the length of the substrate portion 128 in the direction of the arrow X in FIG. 5, the rotary polygon mirror 115 and the scanning lens 118 can be disposed close to each other. As a result, the relative distance between the surface of the photosensitive drum 109 and the optical scanning device 102 can be shortened, and the image forming apparatus 101 can be downsized.

  In the optical deflector 117 of the present embodiment, the fixing portion 133 of the screw 137 of the substrate portion 128 is configured by a cylindrical portion 133a formed to protrude from the base plate 126 to the circuit substrate 127 side by drawing or the like. Then, the lower surface 137a1 of the head 137a of the screw 137 and the top surface 127b of the electric circuit portion on the circuit board 127 are separated from each other by a gap C in the arrow Z direction in FIG. And the electric circuit part on the circuit board 127 was arrange | positioned in the position close | similar to the side surface 133a3 of the cylindrical part 133a rather than the outermost diameter D1 of the head 137a of the screw 137.

  Accordingly, the area around the fixed portion 133 of the circuit board 127 of the optical deflector 117 can be effectively used as an electric circuit section, and the area of the substrate section 128 can be reduced. Thereby, the scanning lens 118 and the rotary polygon mirror 115 can be brought close to each other, and the optical scanning device 102 can be downsized. Further, the cost of the optical deflector 117 and the optical scanning device 102 can be reduced by downsizing.

  Next, the configuration of the second embodiment of the image forming apparatus including the optical scanning device according to the present invention will be described with reference to FIGS. In addition, what was comprised similarly to the said 1st Embodiment attaches | subjects the same member name even if the same code | symbol or a code | symbol differs, and abbreviate | omits description. FIG. 8 is an explanatory perspective view showing the configuration of the optical deflector 200 of the optical scanning device 102 of this embodiment. In the optical deflector 200 of this embodiment shown in FIG. 8, a substrate portion 203 is configured by a conductive base plate 201 and a circuit substrate 202.

  The substrate portion 203 of the present embodiment has a width X2 shorter than the length X1 of the substrate portion 203 in the width direction indicated by the arrow X direction in FIG. 8 and protrudes in the plane direction (arrow Y direction in FIG. 8). The grip portion 204 is provided. A cylindrical portion 133a that protrudes toward the circuit board 202 is formed from the conductive metal base plate 201 by drawing or the like. At a position corresponding to the cylindrical portion 133a of the circuit board 202, a U-shaped cutout portion 202a that can be fitted into the cylindrical portion 133a is provided.

  FIG. 9A is an explanatory plan view for explaining the function and effect of this embodiment. FIG. 9B is an explanatory plan view for comparing operational effects with the first embodiment. When assembling the optical deflectors 117 and 200 shown in FIGS. 9A and 9B to the optical box 113, the optical deflectors 117 and 200 may be gripped by a tool or the like (not shown). In that case, it is necessary to secure a space in which a tool (not shown) for holding the optical deflectors 117 and 200 can be inserted between the rotary polygon mirror 115 and the scanning lens 118.

  When the optical deflector 117 of the first embodiment shown in FIG. 9B is used, a tool insertion region R is provided between the outer peripheral edge 128a of the substrate portion 128 and the incident surface 118a of the scanning lens 118. There is a need.

  On the other hand, the case where the optical deflector 200 of this embodiment shown in FIG. 9A is used is as follows. A gripping portion 204 having a width X2 shorter than a length X1 in the width direction indicated by the arrow X direction of FIG. 8 of the substrate portion 203 provided so as to protrude in the surface direction of the substrate portion 203 (arrow Y direction of FIG. 8) is provided. . Tool insertion regions R can be provided on both sides of the grip portion 204. As a result, the outer peripheral edge 203a of the substrate portion 203 and the incident surface 118a of the scanning lens 118 can be arranged close to each other, and as a result, the distance between the rotary polygon mirror 115 and the incident surface 118a of the scanning lens 118 Can be shortened.

  Here, the relative distance between the rotation center of the rotating shaft 121 of the rotary polygon mirror 115 and the incident surface 118a of the light beam L of the scanning lens 118 when the optical deflector 200 of the present embodiment shown in FIG. Consider A1. In addition, when the optical deflector 117 of the first embodiment shown in FIG. 9B is used, the rotation center of the rotary shaft 121 of the rotary polygon mirror 115 and the incident surface 118a of the light beam L of the scanning lens 118 are relative to each other. Consider the distance A2. The relative distance A1 can be made smaller than the relative distance A2.

  A tool may be used when the optical deflector 200 is assembled to the optical box 113. Even in this case, tool insertion regions R are provided on both sides of the grip portion 204 provided so as to protrude in the surface direction of the substrate portion 203 (in the direction of arrow Y in FIG. 8). Thereby, the rotary polygon mirror 115 and the scanning lens 118 can be brought close to each other.

  The length Y1 in the direction of the arrow Y in FIG. 9A of the optical deflector 200 of the present embodiment shown in FIG. 9A is the same as that in the first embodiment shown in FIG. The length of the optical deflector 117 is slightly larger than the length Y2 in the arrow Y direction in FIG. 9B. In addition, the length X1 of each optical deflector 117,200 of FIG. 9 (a), (b) direction of the arrow X is equal.

  Accordingly, when the optical scanning device 102 can reduce the cost and reduce the size by reducing the length Y2 of the optical deflector 117 in the direction of the arrow Y in FIG. 9B, it is shown in FIG. 9B. The optical deflector 117 of the first embodiment may be used. That is, depending on the configuration of the optical scanning device 102, the substrate portions 128 and 203 of the optical deflectors 117 and 200 shown in FIGS. Other configurations are the same as those in the first embodiment, and the same effects can be obtained.

  Next, the configuration of the third embodiment of the image forming apparatus including the optical scanning device according to the present invention will be described with reference to FIG. In addition, what was comprised similarly to each said embodiment attaches | subjects the same member name even if the same code | symbol or a code | symbol differs, and abbreviate | omits description. FIG. 10 is an explanatory perspective view showing the configuration of the optical deflector 300 of the third embodiment of the optical scanning device 102 of the present embodiment.

  In the optical deflector 117 according to the first embodiment, as shown in FIG. 3, the ground (ground) of the electric circuit portion provided on the circuit board 127 by the caulking portion 136 and the conductive base plate 126 are electrically connected. Connected to ground. In the optical deflector 300 of this embodiment, as shown in FIG. 10, a conductive member 304 is provided instead of the caulking portion 136. The conducting member 304 is preferably, for example, solder. The conductive member 304 electrically connects the side surface 133a3 of the cylindrical portion 133a having conductivity of the fixed portion 133 and the ground (ground) of the electric circuit portion provided on the circuit board 302.

  The board portion 303 of the present embodiment includes a conductive base plate 301 and a circuit board 302. At a position corresponding to the cylindrical portion 133a of the circuit board 302, a U-shaped cutout portion 302a that can be fitted into the cylindrical portion 133a is provided. The area of the circuit board 302 of the present embodiment can be made smaller by the area required for the caulking portion 136 than the area of the circuit board 127 of the optical deflector 117 of the first embodiment shown in FIG. Therefore, the optical deflector 300 of the present embodiment can be further reduced in cost and size as compared with the optical deflector 117 of the first embodiment. Other configurations are the same as those in the above embodiments, and the same effects can be obtained.

  In each of the above-described embodiments, each circuit board 127, 202,... Is disposed on the inner side of the outermost diameter D1 of the head 137a of the screw 137 at one fixed portion 133 provided in each optical deflector 117, 200, 300. The configuration for arranging 302 has been described. In addition, a plurality of fixed portions 133 provided in each of the optical deflectors 117, 200, and 300 can be similarly configured.

  In each of the above embodiments, the fixing portions 133 and 134 provided at two locations of the base plates 126, 201, and 301 are fastened to the fastening portions 139 and 140 provided in the optical box 113 using the screw 137. An example of the optical deflectors 117, 200, and 300 has been described. In addition, the fastening locations for fastening the base plates 126, 201, 301 to the fastening portions provided in the optical box 113 using the screws 137 may be other than two locations.

  In each of the above embodiments, an example in which an electric circuit unit is provided on each circuit board 127, 202, 302 made of a member different from each base plate 126, 201, 301 has been described. In addition, an electric circuit portion can be provided on each base plate 126, 201, 301.

  In each of the above embodiments, as shown in FIG. 4, an example of a configuration in which the rotating shaft 121 is rotatably supported by the bearing 122 has been described. In addition, a bearing for rotatably holding the rotor boss 123 (rotating member) is provided. Further, an electric circuit portion for rotating the rotor boss 123 (rotating member) is mounted, and a substrate portion for holding the bearing is provided. The bearing may be provided so as to be rotatable about a fixed shaft, and a rotating body such as the rotary polygon mirror 115 may be supported by the bearing.

D1 ... Outermost diameter of head 137a of screw 137 113 ... Optical box 117 ... Optical deflector 127b ... Top surface of electric circuit part 128 ... Substrate part 133, 134 ... Fixed part 133a ... Cylindrical part 133a2 ... Axial end part 133a3 ... Side 137,138 ... Screw (screw)
137a, 138a ... Head 137a1, 138a1 ... Underside 137b, 138b ... Shaft

Claims (4)

A light source;
A rotary polygon mirror that deflects and scans a light beam from the light source, a rotary member that supports the rotary polygon mirror, a shaft or a bearing that rotatably holds the rotary member, and an electric circuit that rotationally drives the rotary member An optical deflector having a substrate portion mounted thereon and holding the shaft or the bearing,
An optical box to which the optical deflector is fixed;
A scanning lens that forms an image of a light beam deflected and scanned by the rotary polygon mirror on the surface to be scanned;
An optical scanning device comprising:
The optical deflector is fixed to the optical box via a fixing portion provided on the substrate portion using a screw,
At least one of the fixing portions has a cylindrical portion in which a shaft portion of the screw is inserted, and a lower surface of a head portion of the screw is in contact with an axial end portion.
The board portion is provided with the electric circuit portion at a position closer to the side surface of the cylindrical portion than the outermost diameter of the head portion of the screw, and the top surface of the electric circuit portion and the head portion of the screw An optical scanning device characterized in that the lower surface of the optical scanning device is separated from the lower surface. The cylindrical portion has conductivity,
The optical scanning device according to claim 1, wherein the optical deflector includes a conducting member electrically connected between a side surface of the cylindrical portion and the electric circuit portion.   The optical scanning device according to claim 1, wherein the optical deflector includes a grip portion having a width shorter than a length of the substrate portion in a width direction.   An image forming apparatus comprising the optical scanning device according to claim 1.

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