JP2013171256A - Optical scanning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical scanning device capable of more accurately adjusting a tilt of a rotation shaft 15 in a rotary polygon mirror 3.SOLUTION: An optical scanning device includes: an optical box 25; a circuit board 5 fixed on a bottom surface of the optical box 25; and a rotary polygon mirror 3 rotatably provided on the circuit board 5 so as to deflectively scan a surface to be scanned with a laser beam emitted from a laser unit 1. Also, the optical scanning device includes adjustment means capable of, after the circuit board 5 is fixed on the optical box 25, adjusting a tilt of a rotation shaft 15 by generating a pressing force for pressing the rotation shaft 15 or a bearing 14 provided on the circuit board 5 and pivotally supporting the rotation shaft 15 so that a tilt of the rotation shaft 15 in the rotary polygon mirror 3 varies.

Description

  The present invention relates to an optical scanning device provided in an image forming apparatus.

As an optical scanning device included in an image forming apparatus, an apparatus that employs a configuration in which each optical component is accommodated in an optical box is known. Examples of the optical component include a light source that emits laser light, a rotary polygon mirror that deflects the laser light, and an optical deflection device that includes a circuit board for controlling and driving the rotary polygon mirror. The image forming apparatus forms an electrostatic latent image by scanning the scanning surface of the photosensitive drum with the laser beam emitted from the optical scanning device, and further supplies toner or the like as a developer to the photosensitive drum. Form an image.
Here, when the rotation axis of the rotary polygon mirror is tilted, the scanning position on the surface to be scanned is shifted, and the quality of the formed image is deteriorated.
Therefore, Patent Document 1 is disclosed as means for correcting the tilt of the rotation axis of the rotary polygon mirror. Hereinafter, the configuration for correcting the axis collapse disclosed in Patent Document 1 will be described with reference to FIG. As shown in FIG. 15, an optical deflecting device 301 disclosed in Patent Document 1 includes a rotary shaft 302 of a rotary polygon mirror, a protrusion (bearing) 303 that supports the rotary shaft 302, and a circuit board 304. The protrusion 303 is caulked and fixed to the circuit board 304 and is fitted to the optical box 305. The optical box 305 is provided with a fitting portion 306 that urges the optical shaft 305 in a direction to correct the tilt of the rotating shaft 302 by making point contact with the protruding portion 303. The fitting portion 306 urges the protrusion 303 to deform the caulking portion 307 of the circuit board 304 to correct the axis tilt of the rotating shaft 302.

JP 2008-145952 A

  In Patent Document 1, the protrusion 303 provided in the optical deflection device 301 and the fitting portion 306 of the optical box are brought into point contact to correct the tilting of the rotating shaft 302, and then the circuit board 304 is screwed to the optical box 305. The light deflection device 301 is fixed to the optical box 305. Therefore, there is a concern that the state of point contact may change due to stress or torque due to screw fastening. That is, since the screw fastening is performed after correcting the shaft tilt of the rotating shaft 302, a change occurs in the magnitude and direction of the load generated in the point contact, and the adjustment of the amount and direction of correcting the shaft tilt of the rotating shaft 302 is unstable. There is a possibility.

  Accordingly, an object of the present invention is to provide an optical scanning device capable of more accurately adjusting the inclination of the rotation axis of the rotary polygon mirror.

  The present invention includes a housing, a substrate fixed to the bottom surface of the housing, a rotating polygon mirror provided on the substrate so as to be rotatable so as to deflect and scan the laser light emitted from the light source onto the surface to be scanned, In the optical scanning device, the bearing provided on the rotating shaft or the substrate so as to pivotally support the rotating shaft so that the inclination of the rotating shaft of the rotary polygon mirror changes after the substrate is fixed to the housing. It has an adjustment means which can adjust the inclination of the axis of rotation by generating the pressing force which presses.

  ADVANTAGE OF THE INVENTION According to this invention, the optical scanning device which can adjust the inclination of the rotating shaft of a rotary polygon mirror more correctly can be provided.

The perspective view which shows the optical structure of the optical scanner which concerns on a present Example. Sectional drawing which shows the internal structure of the optical deflection | deviation apparatus based on Example 1. FIG. The perspective view which shows a mode that the optical deflection | deviation apparatus is attached to an optical box in Example 1. FIG. 1 is a bottom perspective view of an optical scanning device according to Embodiment 1. FIG. FIG. 7 is a bottom perspective view illustrating a modification of the optical scanning device according to the first embodiment. Sectional drawing of the optical scanning device which concerns on Example 1. FIG. Diagram showing the relationship between the amount of shaft collapse and load Sectional drawing of the optical scanning device which concerns on Example 1. FIG. The side view of the modification of the optical deflection apparatus concerning Example 1 Sectional drawing and bottom view of the optical scanning device concerning Example 2 Sectional drawing of the optical deflection | deviation apparatus which concerns on Example 2. FIG. The bottom view of the modification of the optical scanning device concerning Example 2 The perspective view which shows a mode that the optical deflection | deviation apparatus is attached to an optical box in Example 3. FIG. FIG. 6 is a diagram illustrating the configuration of an optical scanning device according to a third embodiment. Sectional drawing of the optical scanning device which concerns on a prior art example

(Schematic configuration of optical scanning device)
First, the schematic configuration of the optical scanning device according to the present embodiment will be described with reference to FIG. FIG. 1 is a perspective view illustrating an optical configuration of the optical scanning device according to the present embodiment. The optical scanning apparatus according to the present embodiment is used in an image forming apparatus such as an electrophotographic printer, a digital copying machine, or a digital FAX.

  As shown in FIG. 1, the optical scanning apparatus according to the present embodiment includes, as main components, a laser unit 1 as a light source, an optical deflecting device 2, an Fθ lens 8, a folding mirror 9, a BD mirror 11, and a BD sensor 12. A cylindrical lens 13 is provided. These components are assembled with high accuracy in an optical box as a housing in accordance with predetermined optical performance requirements. The laser unit 1 may be referred to as a light source device, and the light deflection device 2 may be referred to as a scanner motor unit.

  Next, the operation of the optical scanning device according to the present embodiment will be described. First, the laser unit 1 emits a laser beam L and passes through a collimating lens (not shown). Laser light (hereinafter referred to as collimated light) L that has passed through the collimating lens passes through the cylindrical lens 13 and is deflected by the light deflecting device 2. Thereafter, the deflected collimated light L passes through the Fθ lens 8, is reflected by the folding mirror 9, and finally reaches the scanning surface of the photosensitive drum 10 as the scanning body provided in the image forming apparatus. At this time, the collimated light L is optimally narrowed down within the longitudinal width of the photosensitive drum 10 by the Fθ lens 8. Note that the alternate long and short dash line in FIG. 1 represents the collimated light L scanned on the surface to be scanned of the photosensitive drum 10.

A part of the collimated light L deflected by the light deflecting device 2 is reflected by the BD mirror 11 and enters the BD sensor 12. Then, the BD sensor 12 that has detected the collimated light L transmits an output signal to a control unit (not shown) of the laser unit 1. The control unit that has received the output signal controls the laser unit 1 to suppress the shift of the position of the scanning line in the main scanning direction (longitudinal direction of the photosensitive drum 10) based on the output signal. A two-dot chain line in FIG. 1 represents the collimated light L incident on the BD sensor 12.

  The cylindrical lens 13 is used to suppress the positional deviation of the scanning lines on the photosensitive drum 10 in the sub-scanning direction due to a tilting error (so-called surface tilting) of the reflecting surface of the light deflecting device 2. Here, the sub-scanning direction is a direction orthogonal to the main scanning direction and refers to a direction in which a transfer material such as paper is fed. Here, the laser light extracted from the laser unit 1 by the cylindrical lens 13 is compressed in the sub-scanning direction on the reflection surface of the optical deflecting device 2 to form a line image. As a result, a configuration is adopted in which a so-called surface tilt correction optical system in which the reflection surface of the light deflector 2 and the surface to be scanned of the photosensitive drum 10 are in a conjugate relationship in the sub-scanning direction is employed.

  As the optical scanning device operates as described above, a laser beam L is irradiated onto the charged photosensitive drum 10 to form an electrostatic latent image. An image is formed by supplying a developer such as toner to the electrostatic latent image. Here, if the rotation axis of the rotary polygon mirror that reflects and deflects the laser beam L is inclined, the scanning position on the surface to be scanned is shifted, and the quality of the formed image is deteriorated. Therefore, it is desired to correct the tilt when the rotation axis of the rotary polygon mirror is tilted. Hereinafter, the configuration of each embodiment for adjusting and correcting the tilt of the rotation axis of the rotary polygon mirror will be described.

Example 1
Next, the optical deflecting device 2 provided in the optical scanning device according to the first embodiment will be described with reference to FIGS. 1 and 2. FIG. 2 is a cross-sectional view illustrating an internal configuration of the optical deflection apparatus according to the first embodiment. The optical deflecting device 2 according to the first embodiment includes a rotary polygon mirror 3 provided to be rotatable around a rotation shaft 15, a rotor 4 that is a rotary body to which the rotary polygon mirror 3 is attached, a substantially rectangular plate-like circuit board. 5. A bearing 14 for supporting the rotating shaft 15 and a support member 16 are provided. The rotary polygon mirror 3 reflects and deflects the laser beam L emitted from the laser unit 1 to scan the surface to be scanned of the photosensitive drum 10.

  The light deflection apparatus 2 includes a stator 21 having a stator core 19 and a stator coil 20 fixed to the circuit board 5, an elastic body 22, and a fixing ring 23. The rotor 4 includes a yoke 17 and a rotor magnet 18 that are integrally coupled to a support member 16 that is integral with the rotary shaft 15 by caulking or the like. The support member 16 is a metal member made of brass, aluminum, or the like fixed to the outer periphery of the rotating shaft 15 by a method such as press fitting or shrink fitting. The rotary polygon mirror 3 is pressed and fixed to the support member 16 by the elastic body 22 and the fixing ring 23, and rotates integrally with the rotary shaft 15, the rotor 4, and the like. A bearing 14 protrudes on the surface of the circuit board 5 opposite to the surface on which the rotary polygon mirror 3 is provided. The protruding portion of the bearing 14 is a protruding portion. Further, as shown in FIG. 1, the circuit board 5 is mounted with a driving IC 6 for driving the optical deflecting device 2, a connector 7 electrically connected to the outside, and the like.

  Next, means for fixing the optical deflection apparatus 2 according to the first embodiment to the optical box 25 will be described with reference to FIG. FIG. 3 is a perspective view of the optical scanning device according to the first embodiment, illustrating how the light deflecting device is fixed to the optical box. In FIG. 3, the axial direction of the rotary shaft 15 of the rotary polygon mirror 3 is defined as the z-axis direction. Further, the longitudinal direction of the circuit board 5 that is orthogonal to the z-axis and has a substantially rectangular shape is the x-axis direction, and the short direction of the circuit board 5 that is orthogonal to the z-axis and has a substantially rectangular planar shape. Is the y-axis direction. Further, the direction in which the arrows indicating the x-axis, y-axis, and z-axis in FIG. 3 are oriented is the positive direction of each axis direction.

As shown in FIG. 3, the light deflector 2 can be fixed to the bottom surface of the optical box 25 by inserting and fastening screws 26 into screw holes 24 provided in the circuit board 5. On the bottom surface of the optical box 25, a circular seat surface 27 for fastening screws is provided corresponding to the screw holes 24 of the circuit board 5. In the first embodiment, after the light deflecting device 2 is fixed to the optical box 25 in this way, a leaf spring 29 described below is attached from the outside of the optical box 25.

  A through hole 28 is provided in the bottom surface of the optical box 25, and a protruding portion of the bearing 14 that protrudes from the back surface of the circuit board 5 of the optical deflector 2 is inserted. However, since the inner diameter of the through hole 28 is sufficiently larger than the outer diameter of the bearing 14 and there is a gap when the bearing 14 is inserted into the through hole 28, the bearing 14 is fitted to the optical box 25. It cannot be positioned. For this reason, the optical deflection device 2 is positioned by aligning the end surface of the circuit board 5 of the optical deflection device 2 with a positioning pin (not shown) provided in the optical box 25. Alternatively, the rotational center of the rotary polygon mirror 3 may be positioned with respect to a tool (not shown), and the positioning method of the optical deflector 2 with respect to the optical box 25 is not limited to one.

  Next, with reference to FIGS. 4 and 5, adjustment of the inclination of the rotation shaft 15, which is a feature of the optical scanning device according to the first embodiment, will be described. FIG. 4 is a bottom perspective view of the optical scanning device according to the first embodiment. FIG. 5 is a bottom perspective view showing a modification of the first embodiment. As in FIG. 3, the direction in which the arrows indicating the x-axis, y-axis, and z-axis in FIGS. 4 and 5 are directed is the positive direction of each axis.

  As shown in FIG. 4, the optical box 25 has a plurality of fixing portions 31 (31 a, 31 b, 31 c, 31 d) in the circumferential direction of the through hole 28 so that the direction of adjustment of the inclination of the rotation shaft 15 can be selectively changed. , 31e, 31f, 31g, 31h) at equal intervals. In the first embodiment, the fixing portion 31 is a protrusion and is integrally formed with the optical box 25 made of resin. In addition, the fixing | fixed part 31 is not restricted to what is integrally molded with the optical box 25, The thing etc. which press-fit and provide a metal member etc. in the optical box 25 may be used.

  In the first embodiment, the fixing portion 31 has a shape protruding from the bottom outer wall of the optical box 25 by about 5 to 10 mm. In the first embodiment, a leaf spring 29, which is an elastic member, is used as an adjustment unit that can adjust the inclination of the rotary shaft 15. The fixing portion 31 protrudes from the optical box 25 so that the leaf spring 29 can be locked. Further, the leaf spring 29 is provided with a bend 32 for hooking on the fixed portion 31 at both ends thereof. Further, the bearing 14 has an enlarged diameter portion for locking the leaf spring 29. Specifically, as shown in FIG. 4, the outer diameter of the portion where the leaf spring 29 of the bearing 14 is locked to the tip of the protruding portion of the bearing 14 protruding outside from the through hole 28 of the optical box 25. Also, a locking claw 33 having an outer diameter that is about 1 mm thick is provided. In addition, as long as the leaf | plate spring 29 can be latched, not only an enlarged diameter part but the structure which provides a reduced diameter part in the bearing 14 may be sufficient.

As shown in FIG. 4, the leaf spring 29 is elasticated between the fixing portion 31 and the bearing 14 from the outside of the optical box 25 after the circuit board 5 of the optical deflection device 2 is screwed and fixed to the optical box 25. It is attached while pressing to generate force. Thus, by mounting the leaf spring 29, the pressing force is generated in the bearing 14, it is possible to apply a load P _1, an optical deflecting device 2 after bis fastened and fixed to the optical box 25, the rotary polygon mirror 3 The inclination of the rotation shaft 15 can be adjusted. In Example 1, as shown in FIG. 4, the plate spring 29 is attached to the fixed portion 31 a, the fixed portion 31 e, and the bearing 14 while pressing the load P ₁ in order to apply the load P ₁ in the positive direction of the x-axis.

In FIG. 4, the pressing direction by the leaf spring 29 is configured to be the positive direction of the x-axis. However, the method of attaching the leaf spring 29 to the fixing portion 31 is not limited to this, and a plurality of fixing portions are provided. By selecting any one of 31, the pressing direction can be changed. For example, as shown in FIG. 5, to select the fixed portion 31c and the fixed portion 31 g, by attaching the plate spring 29 so as to press them, the load is applied P ₁ the direction in which the pressing force acts as a negative direction of the y-axis be able to.

Next, the correction of the inclination of the rotating shaft 15 of the rotary polygon mirror 3 will be specifically described with reference to FIGS. FIG. 6 is a cross-sectional view of the optical scanning device according to the first embodiment. FIG. 7 is a diagram illustrating the relationship between the amount of shaft tilt and the load on the bearing. Here, as shown in FIG. 6, in the state where the optical deflector 2 is screwed and fixed to the optical box 25, an axis collapse occurs on the rotary shaft 15 of the rotary polygon mirror 3 with respect to the positive direction of the x-axis. Suppose that In this case, the inclination of the rotating shaft 15 can be corrected by pressing the protrusion of the bearing 14 in the positive x-axis direction. That is, as shown in FIG. 4, two points of the fixing portions 31 a and 31 e are selected, the leaf spring 29 is attached, and the bearing 14 is pressed. When the leaf spring 29 is attached as described above, a slight deflection occurs in the vicinity 30 (see FIG. 6) of the circuit board 5 having low rigidity and the bearing 14 (see FIG. 6), the bearing 14 is inclined, and the inclination of the rotating shaft 15 is desired. It is corrected to the value.

  Further, the adjustment amount of the inclination of the rotating shaft 15 may be adjusted by preparing a plurality of leaf springs having different elastic coefficients in advance and selecting an appropriate leaf spring from them. In Example 1, a leaf spring having a load of about 1.2 kgf was selected. In addition, it has been known in advance by the inventors of the present invention that the relationship between the load on the bearing 14 and the amount of shaft collapse has a correlation as shown in FIG.

  Further, the amount of adjustment of the inclination of the rotary shaft 15 can be changed by changing the position in the axial direction (z-axis direction) of the rotary shaft 15 where the pressing force is generated with respect to the bearing 14. This point will be specifically described below with reference to FIGS. FIG. 8 is a cross-sectional view of the optical scanning device according to the first embodiment. In FIG. 8A, the leaf spring abuts on the bearing at a position far from the base of the bearing. In FIG. The leaf spring abuts against the bearing at a position close to the base of. FIG. 9 is a side view of a modification of the optical deflecting device according to the first embodiment.

As shown in FIG. 8 (a), and when a load is applied P ₂ by the leaf spring 29 at a distance l1 from the base of the bearing 14, as shown in FIG. 8 (b), the distance from the base of the bearing 14 l2 the leaf spring 29 of the same elastic force to the position of (l1> l2) compared with the case where a load _{P 2.} In this case, as shown in FIG. 8B, the moment around the joint between the rotary shaft 15 and the circuit board 5 is smaller when the distance from the base of the bearing 14 is shorter. That is, as shown in FIG. 8 (b), when the distance from the root of the bearing 14 is shorter, as shown in FIG. 8 (a), the rotating shaft 15 is longer than when the distance is longer from the root of the bearing 14. The amount of tilt adjustment becomes smaller. As described above, when the same leaf spring 29 is used to finely adjust the inclination of the rotary shaft 15, the pressing position of the leaf spring 29 against the bearing 14 is changed in the axial direction (z-axis direction) of the rotary shaft 15. Good.

  Thereafter, the leaf spring 29 attached at a desired position is adhered to at least one of the bearing 14 and the fixed portion 31 using an adhesive, so that the leaf spring 29 is moved in the z-axis direction by an external impact caused by dropping or the like. It can prevent shifting. In order to prevent the plate spring 29 from shifting in the z-axis direction, a locking claw 71 as a locking portion may be provided in the middle of the bearing 70 as shown in FIG. Thus, by providing the latching claw 71, the leaf spring 29 can be latched and the shift in the z-axis direction can be suppressed.

As described above, in the optical scanning device according to the first embodiment, after the circuit board 5 is screwed to the optical box 25, the inclination of the rotary shaft 15 of the rotary polygon mirror 3 can be adjusted and corrected. Moreover, the amount and direction of adjustment of the inclination of the rotating shaft 15 can be changed by appropriately changing the load of the leaf spring to be used and the position where the leaf spring is attached. Further, the inner diameter of the through hole 28 provided in the bottom surface of the optical box 25 is sufficiently larger than the outer diameter of the bearing 14. Therefore, the bearing 14 and the optical box 25 are not in contact with each other before and after the inclination of the rotary shaft 15 is adjusted, and the pressing force acting on the bearing 14 is not directly transmitted to the optical box 25. That is, as compared with the case where the bearing 14 and the through hole 28 are fitted, the magnitude of the inclination of the rotating shaft 15 with respect to the load becomes large, so that the shaft collapse can be corrected with a small load.

(Example 2)
An optical scanning device according to the second embodiment will be described with reference to FIGS. 10 to 12. 10A and 10B are diagrams for explaining a means for attaching the tension coil spring of the optical scanning device according to the second embodiment. FIG. 10A is a cross-sectional view, and FIG. 10B is a bottom view. FIG. 11 is a cross-sectional view of the optical deflection apparatus according to the second embodiment. FIG. 12 is a bottom view of a modification of the optical scanning device according to the second embodiment. In addition, about the structure same as Example 1, the description is abbreviate | omitted using the same code | symbol.

  In the first embodiment, a configuration in which the bearing 14 that supports the rotating shaft 15 protruding from the back surface of the circuit board 5 of the optical deflecting device 2 is inserted into the through hole 28 provided in the bottom surface of the optical box 25 is used. On the other hand, in the second embodiment, as shown in FIG. 10A, the protruding portion of the rotating shaft 35 protruding from the back surface of the circuit board 5 of the optical deflector 2 is inserted into the through hole 28 of the optical box 25. Is used. That is, the optical deflection apparatus according to the second embodiment has a configuration in which the rotation shaft 35 directly penetrates the through hole 28 and protrudes to the outside of the optical box 37. And as shown in FIG. 11, the rotating shaft 35 is fixed to the circuit board 60 perpendicularly, and the bearing 61 rotates. Further, in the first embodiment, the leaf spring 29 is used to adjust the inclination of the rotating shaft 15, but in the second embodiment, a tension coil spring 39 having hooks at both ends is used as the adjusting means.

  In the second embodiment, the circuit board 60 of the light deflector 36 is screwed and fixed to the optical box 37, and then the protruding portion of the rotating shaft 35 protruding outside the optical box 37 and the fixing portion provided in the optical box 37 are provided. A tension coil spring 39 as an elastic member is attached to 38. As shown in FIG. 11, the rotating shaft 35 has a locking groove 40 for hooking the tension coil spring 39. The fixing portion 38 provided in the optical box 37 has a locking claw 41 on which the hook of the tension coil spring 39 is hooked. Similarly to the first embodiment, the inner diameter of the through hole 28 provided in the optical box 37 is sufficiently larger than the outer diameter of the rotary shaft 35, and the rotary shaft 35 is inserted with a gap.

  Next, adjustment of the inclination of the rotating shaft 35 of the rotary polygon mirror 3 in the second embodiment will be described. After the light deflection device 2 is screwed and fixed to the optical box 37, one hook of the tension coil spring 39 is attached to the rotary shaft 35 and the other hook is attached to a fixing portion 38 provided in the optical box 37. At this time, the tension coil spring 39 is locked by the locking groove 40 of the rotating shaft 35 and the locking claw 41 of the fixed portion 38.

As shown in FIG. 10 (b), by attaching the tension coil spring 39, it is possible to generate a load P ₃ pulling in a direction opposite to the fixing portion 38 fitted with a coil spring 39 pulls the rotary shaft 35. Furthermore, by attaching a plurality of tension coil springs 39 at the same time, the magnitude and direction of the load applied to the rotating shaft 35 can be adjusted. For example, as shown in FIG. 12, if two tension coil springs 39 are attached at the same time, a load P ₄ that is a resultant force of the loads P ₃ applied in two different directions can be applied to the rotating shaft 35. In this case, the load P ₄ is a force that acts on an angle obtained by dividing the angle between the two directions in which each load P ₃ acts. That is, by attaching a plurality of tension coil springs 39 at the same time, the direction of the load applied to the rotating shaft 35 can be adjusted without being limited to the direction in which the rotating shaft 35 and the fixed portion 38 face each other.

As described above, in the optical scanning device according to the second embodiment, after the circuit board 60 is screw-fastened to the optical box 37 using the tension spring coil 39, the inclination of the rotary shaft 35 of the rotary polygon mirror 3 is increased. It can be adjusted and corrected. Further, the direction of the load acting on the rotation shaft 35 can be changed by selecting which of the plurality of fixing portions 38 provided in the circumferential direction of the rotation shaft 35 is attached to the tension coil spring 39. Moreover, the magnitude | size and direction of the load concerning the rotating shaft 35 can be adjusted by attaching the several tension coil spring 39 simultaneously. In addition, the tension coil spring 39 is locked by the locking groove 40 of the rotating shaft 35 and the locking claw 41 of the fixed portion 38, so that the displacement in the rotating shaft 35 direction can be suppressed.

(Example 3)
Next, an optical scanning device according to Example 3 will be described with reference to FIGS. FIG. 13 is a perspective view of the optical scanning device according to the third embodiment, illustrating a state in which the optical deflection device is attached to the optical box. 14A and 14B are diagrams illustrating the configuration of the optical scanning device according to the third embodiment. FIG. 14A is a cross-sectional view of the optical scanning device, and FIG. 14B is a perspective view of an elastic member. . In addition, about the structure same as Example 1, the description is abbreviate | omitted using the same code | symbol.

  In the first embodiment, a configuration in which the fixing portion 31 protruding on the bottom surface of the optical box 25 is employed is adopted. On the other hand, in the third embodiment, the through holes 45 provided in the optical box 44 are equally spaced in the circumferential direction. The structure which provides the notch 46 as a fixing | fixed part in this is employ | adopted. Similarly to the first embodiment, the inner diameter of the through hole 45 provided in the optical box 44 is sufficiently larger than the outer diameter of the bearing 43, and the bearing 43 is inserted with a sufficient gap with respect to the through hole 45. ing. In the first embodiment, the leaf spring 29 is used as the adjusting means. However, in the third embodiment, a wedge-shaped elastic member 47 is used as the adjusting means.

The wedge-shaped elastic member 47 is attached by being pushed into the notch 46 from the outside of the optical box 44 after fastening the screw 48 to the optical box 44 and fixing the light deflecting device 2 to the optical box 44. Thus, by pushing the elastic member 47, the bearing 43 can apply a load P _5, the optical deflection device 42 after screw fastened and fixed to the optical box 44, the inclination of the rotary polygon mirror 3 of the rotary shaft 49 Can be adjusted. The elastic member 47 may be provided with locking claws and the notch 46 may be provided with a plurality of locking holes.

  As shown in FIG. 14B, the elastic member 47 is provided with a plurality of locking holes 51 at equal intervals on one side of the wedge shape. On the other hand, a locking claw 50 is provided on a part of the outer wall of the notch 46 provided in the optical box 44 in order to maintain the position when the elastic member 47 is pushed. With such a configuration, by changing the locking position of the elastic member 47 with respect to the notch 46 in the axial direction of the rotating shaft 49, that is, by arbitrarily selecting the position of the locking hole 51 to be used and changing the push-in amount. The magnitude of the pressing force on the bearing 43 can be changed. Further, by attaching the locking claw 50 to the locking hole 51 in this way, it is possible to prevent the elastic member from being detached even when an external impact load due to dropping or the like is applied.

  As described above, in the optical scanning device according to the third embodiment, after the circuit board 80 is screwed to the optical box 44 using the wedge-shaped elastic member 47, the rotation shaft 49 of the rotary polygon mirror 3 is fixed. The tilt can be adjusted and corrected. Further, the direction of the load acting on the bearing 43 can be changed by selecting which of the plurality of notches 46 provided in the circumferential direction of the bearing 43 is to be pushed into the elastic member 47. Further, by changing the locking position of the elastic member 47 with respect to the notch 46 in the axial direction of the rotating shaft 49, the magnitude of the pressing force with respect to the bearing 43 can be changed. Further, by attaching a plurality of elastic members 47 simultaneously, it is possible to adjust the direction of the load acting on the rotation shaft 49 without being limited to the direction in which the rotation shaft 49 and the notch 46 face each other.

Laser unit ... 1, light deflecting device ... 2, rotary polygon mirror ... 3, circuit board ... 5, rotating shaft ... 15, optical box ... 25, elastic member ... 29, laser beam ... L

Claims (9)

A housing,
A substrate fixed to the bottom surface of the housing;
A rotating polygon mirror provided on the substrate so as to be rotatable so as to deflect and scan the laser beam emitted from the light source on the surface to be scanned;
In an optical scanning device comprising:
After the substrate is fixed to the housing, a pressing force is generated to press the rotating shaft or a bearing provided on the substrate and supporting the rotating shaft so that the inclination of the rotating shaft of the rotary polygon mirror changes. An optical scanning device comprising adjustment means capable of adjusting the inclination of the rotation shaft by adjusting the rotation axis. The rotating shaft or the bearing has a protruding portion that protrudes from a surface opposite to the surface on the side of the substrate on which the rotating polygon mirror is provided,
The housing has a fixing portion for attaching the adjusting means,
The adjusting means is an elastic member, and is attached between the protruding portion and the fixed portion so as to generate an elastic force between the protruding portion and the fixed portion, thereby generating the pressing force. The optical scanning device according to claim 1.   3. The fixing unit according to claim 2, wherein the fixing unit is a projection capable of locking the adjusting unit, and a plurality of the fixing units are provided in a circumferential direction of the rotating shaft so that a direction in which the pressing force works can be selectively changed. The optical scanning device according to 1.   The plurality of fixing portions are notches capable of locking the adjusting means, and a plurality of the fixing portions are provided in the circumferential direction of the rotating shaft so that the direction in which the pressing force works can be selectively changed. 2. The optical scanning device according to 2.   5. The adjustment unit according to claim 2, wherein the adjustment amount of the inclination of the rotation shaft can be changed by changing a position where the pressing force is applied in an axial direction of the rotation shaft. 2. An optical scanning device according to item 1.   The said rotating shaft or the said bearing has a diameter reduction part or diameter expansion part for latching the said adjustment means to the said protrusion part, The any one of Claims 2 thru | or 5 characterized by the above-mentioned. Optical scanning device.   7. The adjusting device according to claim 2, wherein the adjustment means is configured to change a magnitude of the pressing force by changing a locking position with respect to the fixed portion in an axial direction of the rotating shaft. The optical scanning device according to any one of the above.   8. The optical according to claim 2, wherein the rotating shaft and the bearing are not in contact with the housing before and after the adjustment of the inclination of the rotating shaft by the adjusting means. Scanning device.   9. The optical scanning device according to claim 2, wherein the adjusting unit is fixed to at least one of the rotating shaft, the bearing, or the fixing portion with an adhesive. 10.

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