JP6136262B2 - Optical scanning device - Google Patents

Description

  The present invention relates to an optical scanning device including a holding member that holds a light source and an optical element.

  2. Description of the Related Art Conventionally, there is known an optical scanning device in which a light source composed of a semiconductor laser and a coupling lens (optical element) that converts laser light from the light source into a light beam are held by one holding member (for example, Patent Documents). 1). In this optical scanning device, the holding member has a through hole, and is fixed to the frame of the optical scanning device by a screw inserted through the through hole.

JP 2012-173667 A

  However, when the holding member is fixed to the frame with screws as in the above-described technique, the distortion of the screwed portion of the holding member affects the entire holding member, and the positional relationship between the light source and the optical element may be shifted. is there.

  SUMMARY An advantage of some aspects of the invention is that it provides an optical scanning device capable of improving the positional accuracy of a light source and an optical element.

In order to achieve the above-described object, in the optical scanning device of the present invention, a light source, an optical element that converts laser light from the light source into a light beam, a holding member that holds the light source and the optical element, and a holding member are fixed. And a fixed wall.
The holding member has a main body that holds the light source and the optical element, and an extending portion that extends from the main body and has an opening for fixing the holding member to the fixing wall with a screw.
The extending portion is disposed with the opening interposed therebetween and has a pair of through holes penetrating toward the fixed wall. The through hole is a seat surface of the screw as viewed from the direction in which the opening and the through hole are aligned. The extending portion is bent by tightening a screw at a portion between the pair of through holes.

  According to the optical scanning device configured as described above, when the holding member is fixed to the fixed wall with a screw, the holding member is only a portion between the pair of through holes of the extending portion, that is, around the opening. Since it bends, a main-body part cannot change easily. Thereby, the positional accuracy of a light source and an optical element can be improved.

Then, in the optical scanning apparatus described above, the extending portion is in a position across the opening from a direction perpendicular to the direction in which the pair of through holes are arranged, has a pair of convex portions protruding toward the fixed wall, a pair It can be set as the structure which the convex part of is contacting the fixed wall.

Further, in the above-described optical scanning device having a protrusion on the extension, the extension is provided at two positions sandwiching the main body in at least a direction orthogonal to the direction in which the light source and the optical element are arranged, and a pair of protrusions. one of the parts is preferably provided at a position sandwiching the optical element in a direction perpendicular to the direction in which the light source and the optical element are arranged.

  According to the optical scanning device configured as described above, since the convex portion is in contact with the fixed wall at a position sandwiching the optical element, it is possible to suppress the rotation of the holding member and improve the positional accuracy of the optical element. Can do.

Then, the optical scanning device having a convex portion in the extending portion described above includes a deflector that deflects the laser light from the light source, a light receiving sensor that receives the laser light deflected by the deflector and generates a detection signal, And a lens for guiding laser light to the light receiving sensor.
In this case, it is desirable that the extending portion holds the lens on the outer side of the convex portion and the through hole than the opening portion.

  According to the optical scanning device configured as described above, since the lens is disposed outside the portion that bends when the holding member is fixed to the fixed wall, the positional accuracy of the lens can be improved.

  In the optical scanning device described above, the fixed wall may be made of sheet metal.

  In this case, it is desirable that the holding member has a boss extending from the main body portion, and the fixing wall has an engaging portion through which the boss can be inserted.

  According to the optical scanning device configured as described above, the positioning boss can be provided more easily than when the boss is provided on the fixed wall made of sheet metal.

  In the optical scanning device described above, it is desirable that the pair of through holes are formed so as to be line symmetric with respect to a straight line passing through the center of the opening and orthogonal to the direction in which the opening and the through hole face each other.

  According to the optical scanning device configured as described above, since the periphery of the opening is bent substantially uniformly, the holding member can be prevented from being inclined.

In the optical scanning device described above, the extending portion may be in contact with the fixed wall at a position sandwiching the opening in a direction orthogonal to the direction in which the opening and the through hole are arranged.
In this case, the through hole can be configured to extend at least to the pair of convex portions in the direction in which the pair of convex portions are arranged .

  According to the present invention, when the holding member is fixed to the fixing wall with a screw, the holding member bends only around the portion between the pair of through holes of the extension portion, that is, around the opening portion. Difficult to deform. Thereby, the positional accuracy of a light source and an optical element can be improved.

1 is a perspective view showing an optical scanning device according to an embodiment of the present invention. It is the perspective view which looked at the light source device from the top. It is the perspective view which looked at the light source device from the bottom. It is a disassembled perspective view which shows a flame | frame and a light source device. It is sectional drawing which shows the extension part in the state which fixed the holding member to the flame | frame. It is the perspective view which looked at the light source device in a modification from the bottom.

  Next, an embodiment of the present invention will be described in detail with reference to the drawings as appropriate. In the following description, first, a schematic configuration of the optical scanning device according to the embodiment of the present invention will be briefly described, and then a characteristic part of the present invention will be described in detail.

<Schematic configuration of optical scanning device>
As shown in FIG. 1, the optical scanning device 1 mainly includes a light source device 2, a polygon mirror 3 as an example of a deflector, and a scanning lens 4. The laser beam emitted from the light source device 2 is not illustrated. Condensed in the form of a spot on the surface to be scanned of the photosensitive drum, and the surface to be scanned is scanned. Each optical component is fixed on a fixed wall 210 formed in a substantially flat plate shape of the frame 200.

  As shown in FIG. 2, the light source device 2 includes a semiconductor laser 10 as an example of a light source, a control board 20, an aperture stop 30, a coupling lens 40 as an example of an optical element, and a collection as an example of a lens. The optical lens 50, the light receiving sensor 60 (see FIG. 1), and the holding member 100 are mainly provided.

  The semiconductor laser 10 is a known element that emits laser light, and the lead pin 11 is connected to the control board 20. The semiconductor laser 10 is blinked corresponding to an image to be exposed on the surface to be scanned by a control device (not shown).

  The control board 20 is a substantially rectangular printed board provided with a circuit (not shown) for supplying power to the semiconductor laser 10.

  The aperture stop 30 is a plate-like member having a substantially rectangular opening and defines the diameter of the laser beam from the semiconductor laser 10.

  The coupling lens 40 is a lens that converts the laser light from the semiconductor laser 10 into a light beam. Specifically, the coupling lens 40 is disposed between the aperture stop 30 and the polygon mirror 3, and emits laser light emitted from the semiconductor laser 10 and passed through the aperture stop 30 in the main scanning direction (laser light in FIG. 1). 1 is a direction that swings to the left and right with respect to the traveling direction of the light beam, and is a light beam that converges slightly in the direction deflected by the polygon mirror 3, and is a sub-scanning direction (a direction perpendicular to the main scanning direction and a vertical direction in FIG. ) Is a lens that forms an image in the vicinity of the mirror surface 3 </ b> A of the polygon mirror 3. The coupling lens 40 has different diffraction powers in the main scanning direction and the sub-scanning direction, and has different refractive powers in the main scanning direction and the sub-scanning direction.

  The condenser lens 50 is a lens for guiding the laser light deflected by the polygon mirror 3 to a light receiving sensor 60 described later, and is disposed between the polygon mirror 3 and the light receiving sensor 60.

  As shown in FIG. 1, the light receiving sensor 60 is a sensor that receives a laser beam deflected by a polygon mirror 3 described later and generates a detection signal, and is provided on the control board 20.

  The holding member 100 is a member that holds the semiconductor laser 10, the control substrate 20, the coupling lens 40, and the condenser lens 50, and is fixed to the fixed wall 210 of the frame 200. The detailed configuration of the holding member 100 will be described later.

  In the light source device 2 configured as described above, the semiconductor laser 10 is appropriately blinked based on the image data after a predetermined time has elapsed since the laser light was detected by the light receiving sensor 60.

  The polygon mirror 3 is a member in which four mirror surfaces 3A are arranged at an equal distance from the rotation shaft 3B, and reflects the laser light that has passed through the coupling lens 40 by rotating at a constant speed around the rotation shaft 3B. Thus, it is deflected in the main scanning direction.

  The scanning lens 4 is a lens through which the laser light deflected by the polygon mirror 3 passes. The scanning lens 4 converges or refracts the laser light in the main scanning direction and the sub-scanning direction, thereby forming the laser light in a spot shape on the surface to be scanned and tilting the mirror surface 3A of the polygon mirror 3. Correct. Further, the scanning lens 4 has an fθ characteristic such that the laser beam deflected at a constant angular velocity by the polygon mirror 3 is scanned on the surface to be scanned at a constant velocity.

<Detailed configuration of holding member>
Next, a detailed configuration of the holding member 100 of the light source device 2 will be described. In the following description, the direction in which the semiconductor laser 10 and the coupling lens 40 are arranged, that is, the optical axis direction is referred to as “front-rear direction”. Further, a direction perpendicular to the optical axis direction and along the fixed wall 210 of the frame 200 is referred to as “left-right direction”, and a direction orthogonal to the optical axis direction and the fixed wall 210 and the holding member 100 are aligned is referred to as “vertical direction”.

  As shown in FIG. 2, the holding member 100 is made of resin, and is disposed on the left and right sides of the main body 101 so as to sandwich the main body 101 with the main body 101 holding the semiconductor laser 10 and the coupling lens 40. And a pair of extending portions 102.

  The main body 101 extends in the front-rear direction so as to connect the light source support wall 110 that supports the semiconductor laser 10, the aperture stop 30 that faces the light source support wall 110 in the front-rear direction, and the light source support wall 110 and the aperture stop 30. It has a pair of side walls 120 that face each other in the left-right direction, and a light source support wall 110, an aperture stop 30, and a bottom wall 130 that is formed so as to connect the lower ends of the pair of side walls 120.

  The pair of side walls 120 and the bottom wall 130 extend to the outside in the front-rear direction with respect to the aperture stop 30, and a coupling lens that holds the coupling lens 40 in a space outside the aperture stop 30 of the main body 101. A holding unit 140 is provided. That is, the coupling lens holding part 140 is a concave part that is provided on the opposite side to the semiconductor laser 10 across the aperture stop 30 and is open upward and rearward.

  The light source support wall 110 has an opening 111 penetrating in the front-rear direction where the tip of the semiconductor laser 10 is disposed. The opening 111 is formed at a position where the semiconductor laser 10, the opening of the aperture stop 30, and the coupling lens 40 are aligned.

  As shown in FIG. 3, the bottom wall 130 is formed with two bosses 131 projecting downward from the fixed wall 210 side of the frame 200, that is, the lower side. The two bosses 131 are arranged side by side in the front-rear direction. More specifically, the front boss 131 is provided below the opening 111 of the light source support wall 110, and the rear boss 131 is provided below the aperture stop 30.

  The main body 101 is provided with a pin 112 projecting outward in the front-rear direction on the front surface (specifically, the front end edge of the bottom wall 130).

  As shown in FIG. 2, the extension portion 102 extends from the bottom wall 130 of the main body portion 101 toward the outer side in the left-right direction, and extends from the light source support wall 110 of the main body portion 101 toward the outer side in the left-right direction. It is formed in a substantially L shape having a front wall 160. The right extension 102 has a condensing lens support 170 that supports the condensing lens 50.

  Each fixed wall 150 is arranged with an opening 151 for fixing the holding member 100 to the fixing wall 210 of the frame 200 with a screw B (see FIG. 4) and the opening 151 sandwiched from the left and right directions. A pair of through holes 152 are formed. Further, as shown in FIG. 3, legs 153 as an example of a pair of convex portions arranged with the opening 151 sandwiched in the front-rear direction are provided on the lower surface of the fixed wall 150.

  The opening 151 is a hole penetrating in the vertical direction having a smaller diameter than the seating surface of the screw B (see FIG. 4).

  The pair of through holes 152 are slit-like holes that penetrate in the vertical direction, that is, toward the fixed wall 210 and are long in the front-rear direction. The pair of through holes 152 are formed to be substantially line symmetric with respect to a straight line L extending in the front-rear direction (a direction orthogonal to the direction in which the opening 151 and the through hole 152 face each other) through the center of the opening 151. . The through hole 152 extends to the outside of a range where the seat surface of the screw B is seen when viewed from the direction in which the opening 151 and the through hole 152 are arranged, that is, from the left-right direction.

  The pair of legs 153 are formed so as to protrude downward from the lower surface of the fixed wall 150. The pair of legs 153 are provided at positions outside the through-hole 152 in the front-rear direction when viewed from the left-right direction. And the leg 153 provided in the left extension part 102 and the leg 153 provided in the right extension part 102 are formed at substantially the same position in the front-rear direction, and provided at the rear side. The leg 153 is arranged at a position sandwiching the coupling lens 40 in the left-right direction.

  As shown in FIG. 2, the condensing lens support 170 is provided at the rear end of the right extension 102. The condensing lens support portion 170 is formed so as to protrude rearward from the fixed wall 150 of the extension portion 102, and has a concave portion 171 that opens upward in which the condensing lens 50 is fitted. Thereby, the condensing lens support part 170 can hold | maintain the condensing lens 50 in the outer side of the through-hole 152 and the leg 153 rather than the opening part 151 (refer FIG. 3).

  The extending portion 102 is provided with a pin 161 that extends outward from the front surface of the right extending portion 102 (the front end edge of the fixed wall 150) in the front-rear direction.

  With respect to the holding member 100 configured as described above, the control board 20 is disposed along the front surface of the holding member 100 (the front surface in the front-rear direction of the light source support wall 110), as shown in FIGS. ing. The control board 20 includes a hole (not shown) in which the pin 112 of the main body part 101 and the pin 161 of the extension part 102 are formed in the control board 20 and a long hole extending long in the direction (left-right direction) toward the hole. By being inserted through (not shown), it is positioned with respect to the holding member 100 and is fixed to the extending portion 102 with screws (not shown).

  The semiconductor laser 10 has a tip fitted into the opening 111 of the light source support wall 110 and is fixed to the light source support wall 110 with an adhesive or the like.

  The coupling lens 40 is disposed on the coupling lens holding unit 140 and is fixed to the main body 101 by being pressed against the rear surface of the aperture stop 30 by the clip 180. The clip 180 is a metal plate formed in a substantially U shape, and sandwiches the rear part of the main body 101. A portion of the clip 180 corresponding to the coupling lens 40 is notched, and a leaf spring that presses the coupling lens 40 toward the aperture stop 30 extends from the edge of the notch.

  The condensing lens 50 is fitted into the concave portion 171 of the condensing lens support 170 and is fixed to the condensing lens support 170 with an adhesive or the like.

<Detailed configuration of fixed wall>
Next, a detailed configuration of the fixed wall 210 to which the holding member 100 is fixed will be described.

  As shown in FIG. 4, the fixed wall 210 is formed of a sheet metal, and a pair of pedestals 211 arranged in the left-right direction at a portion to which the holding member 100 is fixed, and an engaging portion disposed between the pair of pedestals 211. As an example, a positioning hole 212 and a long hole 213 are provided.

  The pair of bases 211 is formed by plastically deforming the fixed wall 210. The upper surface (seat surface) of the pedestal 211 is formed at a position corresponding to the extending portion 102 of the holding member 100 and is longer in the front-rear direction than the extending portion 102. A hole 211A into which the screw B is screwed is formed on the upper surface of each pedestal 211.

  The positioning hole 212 and the long hole 213 are arranged side by side in the front-rear direction. The long hole 213 is elongated in the direction toward the positioning hole 212, that is, in the front-rear direction.

  The holding member 100 is positioned relative to the fixed wall 210 by inserting two bosses 131 (see FIG. 3) through the positioning hole 212 and the long hole 213 with respect to the fixed wall 210 formed in this way. Yes. Specifically, the holding member 100 is positioned with respect to the fixed wall 210 by inserting the front boss 131 through the positioning hole 212. Then, the rear boss 131 is inserted into the elongated hole 213 so that the holding member 100 does not rotate around the front boss 131. Then, the holding member 100 is fixed to the fixed wall 210 by screwing the screw B inserted through the opening 151 of the extension portion 102 into the hole 211 </ b> A of the base 211.

  As shown in FIG. 5, the holding member 100 fixed to the fixed wall 210 is placed on the pedestal 211 so that the legs 153 of the extension portion 102 are in contact with the upper surface of the pedestal 211. Then, by screwing the screw B into the hole 211A of the fixed wall 210, a portion between the fixed wall 150 of the extension portion 102 between the pair of through holes 152, more specifically, the pair of legs 153 and the pair of through holes. The portion surrounded by the hole 152 is bent, and the edge of the opening 151 is sandwiched between the fixed wall 210 and the seating surface of the screw B.

The operation and effect of the optical scanning device 1 configured as described above will be described.
The holding member 100 is provided with a pair of through holes 152 so as to sandwich the opening 151 through which the screw B is inserted. When the holding member 100 is fixed to the fixing wall 210 with the screw B, the pair of through holes 152 and the pair of legs are provided. Since only the portion around the opening 151 surrounded by 153 is bent, the main body 101 is not deformed, and the positions of the semiconductor laser 10 and the coupling lens 40 are not displaced. Thereby, the positional accuracy of the semiconductor laser 10 and the coupling lens 40 can be improved.

  The pair of through-holes 152 are substantially line-symmetric with respect to a straight line L that passes through the center of the opening 151 and extends in a direction (front-rear direction) perpendicular to the direction in which the opening 151 and the through-hole 152 are arranged (left-right direction). Since it is formed, the periphery of the opening 151 bends substantially evenly. Thereby, it is possible to suppress the tilting of the holding member 100 and to further improve the positional accuracy of the semiconductor laser 10 and the coupling lens 40.

  And the extension part 102 fixed to the fixed wall 210 is provided so that the main-body part 101 may be pinched | interposed from the left-right direction, and the leg 153 of the rear side of the left-right extension part 102 may pinch | couple the coupling lens 40 from the left-right direction. Therefore, since the periphery of the coupling lens 40 of the main body 101 is prevented from rotating and tilting, the positional accuracy of the coupling lens 40 can be improved.

  Further, the condensing lens support portion 170 is outside the leg 153 and the through hole 152 from the opening portion 151 of the extension portion 102, that is, outside the portion that bends when the holding member 100 is fixed to the fixed wall 210. Since it is formed, even if the periphery of the opening 151 is bent, the position of the condensing lens support 170 is difficult to shift. Thereby, the positional accuracy of the condensing lens 50 hold | maintained at the condensing lens support part 170 can be improved.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment. About a concrete structure, it can change suitably in the range which does not deviate from the meaning of this invention.

  In the embodiment, the leg 153 provided in the extending part 102 is provided on the outer side in the front-rear direction than the through hole 152, but the present invention is not limited to this. For example, as shown in FIG. 6, the leg 153A may be provided on the inner side in the front-rear direction than the front-rear end of the through hole 152A. That is, the through hole 152A may extend at least to the leg 153A in the front-rear direction.

  With this configuration, when the holding member 100 is fixed to the fixed wall 210, it is possible to bend only around the opening 151 of the extension portion 102, and to hold the holding member 100 more than in the above embodiment. The size of the front and rear of the member 100 can be reduced.

  In the embodiment, the leg 153 protruding from the lower surface of the extension portion 102 is configured to contact the fixed wall 210, but the present invention is not limited to this. For example, the fixed wall 150 of the extending portion 102 has a shape in which a portion sandwiched between the pair of through holes 152 is raised one step above the other portions, and the pair of through holes 152 of the fixed wall 150 The outer portion may be in contact with the fixed wall 210.

  In the embodiment, the extending portion 102 of the holding member 100 is provided with a leg 153 (convex portion) that protrudes toward the fixed wall 210, and the leg 153 is configured to contact the pedestal 211 of the fixed wall 210. However, the present invention is not limited to this. For example, a convex portion that protrudes toward the holding member 100 is provided on the pedestal 211 of the fixed wall 210, and this convex portion is configured to contact the extending portion 102 at a position sandwiching the opening 151 from the front-rear direction. Good.

  In the embodiment, the pair of through holes 152 are provided so as to sandwich the opening 151 from the left-right direction, and the pair of legs 153 are provided so as to sandwich the opening 151 from the front-rear direction. It is not limited to this. For example, the pair of through holes may be provided so as to sandwich the opening 151 from the front-rear direction, and the pair of legs may be provided so as to sandwich the opening 151 from the left-right direction.

  In the above embodiment, the extension portion 102 is in contact with the fixed wall 210 at a position sandwiching the opening portion 151 in a direction (front-rear direction) perpendicular to the direction in which the opening portion 151 and the through hole 152 are arranged. Is not limited to this. For example, the extension 102 may be in contact with the fixed wall 210 at a position sandwiching the opening 151 outside the through hole 152 in the direction in which the opening 151 and the through hole 152 are arranged (left and right direction).

DESCRIPTION OF SYMBOLS 1 Optical scanning device 3 Polygon mirror 10 Semiconductor laser 40 Coupling lens 50 Condensing lens 60 Light receiving sensor 100 Holding member 101 Main body part 102 Extension part 131 Boss 151 Opening part 152 Through-hole 153 Leg 210 Fixed wall 212 Positioning hole 213 Long hole L straight line

Claims (8)

A light source;
An optical element for converting laser light from the light source into a light beam;
A holding member for holding the light source and the optical element;
An optical scanning device comprising a fixed wall to which the holding member is fixed,
The holding member includes a main body portion that holds the light source and the optical element, and an extending portion that extends from the main body portion and has an opening for fixing the holding member to the fixing wall with a screw. Have
The extending portion is disposed with the opening interposed therebetween, and has a pair of through holes penetrating toward the fixed wall,
The through-hole extends to the outside of a range that becomes a seating surface of the screw as seen from the direction in which the opening and the through-hole are aligned,
In the optical scanning device, the extension portion is bent by tightening the screw at a portion between the pair of through holes. The extending portion has a pair of convex portions projecting toward the fixed wall at a position sandwiching the opening portion from a direction orthogonal to the direction in which the pair of through holes are arranged,
The optical scanning device according to claim 1, wherein the pair of convex portions are in contact with the fixed wall. The extension part is provided at two locations sandwiching the main body part in at least a direction orthogonal to the direction in which the light source and the optical element are arranged,
3. The optical scanning device according to claim 2, wherein one of the pair of convex portions is provided at a position sandwiching the optical element in a direction orthogonal to a direction in which the light source and the optical element are arranged. A deflector for deflecting laser light from the light source;
A light receiving sensor that receives the laser light deflected by the deflector and generates a detection signal;
A lens for guiding laser light to the light receiving sensor,
4. The light according to claim 2, wherein the extension portion holds the lens outside the convex portion and the through hole from the opening portion. 5. Scanning device.   The optical scanning device according to claim 1, wherein the fixed wall is made of sheet metal. The holding member has a boss extending from the main body,
The optical scanning device according to claim 5, wherein the fixed wall has an engaging portion through which the boss can be inserted.   The pair of through holes are formed so as to be line symmetric with respect to a straight line that passes through the center of the opening and is orthogonal to a direction in which the opening and the through hole face each other. The optical scanning device according to claim 6. Before SL through hole in the direction in which the pair of convex portions are arranged, an optical scanning device according to any one of the preceding claims 2, characterized in that it extends to at least the pair of convex portions.

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