JPH1031180A - Polygon scanner and method of manufacturing the same - Google Patents

Abstract

(57) Abstract: An object of the present invention is to provide a polygon scanner in which deformation due to distortion of a polygon mirror during high-speed rotation is reduced, and a method of manufacturing the same. The light is scanned by rotating a rotating body having a cylindrical polygon mirror provided with a plurality of reflecting surfaces for reflecting light, upper and lower surfaces, and a flange for mounting the polygon mirror. In a polygon scanner, a through hole is provided in one of a polygon mirror and a flange portion, and a projection is provided in the other, so that the flange portion is in close contact with an upper surface or a lower surface of the polygon mirror, and a through hole is provided. Achieved by fixing with an adhesive filled in the holes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polygon motor scanner used in an image forming apparatus, and more particularly, to a polygon motor having a thrust bearing including a slide bearing.

[0002]

2. Description of the Related Art Conventionally, for scanning a laser beam in a laser printer or the like, a polygon scanner driving device in which a polygon mirror 23 is attached to a rotating member such as a flange member 22 as shown in FIG. 1 is used.

This polygon scanner driving device includes a face-to-face brushless DC motor having a stator portion and a rotor portion, and a flange member 22 of a rotor portion which is supported on a fixed shaft 1 of the stator portion via a sliding bearing 9. Is driven to rotate together with the polygon mirror 23.

[0004] The stator portion includes a fixed shaft 1 having a spherical end formed with a spherical surface, a collar 2 into which the fixed shaft 1 is press-fitted, and a base member 3 for fixing the collar 2 so that its axis is vertical. A substrate 4 to be screwed (not shown) onto the base member 3, a winding coil 5 adhered and fixed to a predetermined position of the substrate 4, and a substrate 4 at a predetermined position in the winding coil 5;
And a Hall element 6 for detecting the magnetic pole of the rotor magnet 15, a control circuit 7 fixed on the substrate 4 for switching the excitation, and a connector 8.

[0005] Further, the rotor portion is provided with a thrust cover 11 to which a thrust plate 10 for supporting the radial direction is fixed.
And a female screw part 22b provided in the vicinity of the outer periphery of the flange member 22 for bonding and fixing the thrust cover 11, a rotor yoke 14 inserted and attached to the cylindrical convex part 22c of the flange member 22, and a rotor yoke 14 bonded to the rotor yoke 14. And a rotor magnet 15.

In this conventional polygon scanner driving device, as shown in FIG. 1, a rotor yoke is fixed to a lower surface of a flange member 22 to which a polygon mirror 23 is attached.
A rotor magnet 15 is fixed to a lower surface of the rotor yoke 14. Also, the central through hole 2 of the flange member 22
A fixed shaft 1 is attached to the inside of 2a via a slide bearing 9, a thrust plate 10, and a thrust cover 11, and a lower end of the fixed shaft 1 is fixed to a base member 3 and a substrate 4 via a collar 2. I have. On the substrate 4, a winding coil 5 facing the rotor magnet 15 via a predetermined gap, a Hall element 6 in the winding coil 5, a control circuit 7 for switching excitation, and a connector 8 are provided.

The polygon mirror 23 of such a polygon scanner driving device has an outer peripheral surface (side surface) as shown in FIG.
Is a regular hexagonal prism having six reflecting surfaces 23r. Further, the polygon mirror 23 is provided with a mounting hole 23a having a circular cross section coaxially with its axis and penetrating from the top surface to the bottom surface. In the flange member 22 to which the polygon mirror 23 is attached, a female screw portion 22b to which the tightening screw 16 is screwed is formed corresponding to the through hole 23b of the polygon mirror 23.

As shown in FIG. 1, in order to attach such a polygon mirror 23 to the flange member 22, first,
A mounting hole 23 a of a regular hexagonal columnar body forming the polygon mirror 23 is fitted to the flange member 22. Next, the tightening screw 16 is inserted into the through hole 23b, and the tightening screw 16 is screwed into the female screw portion 22b of the flange member 22 to tighten the polygon mirror 23. The polygon mirror 23 mounted in this way scans the light beam on the side reflection surface 23r while rotating about the axis of the regular hexagonal prism.

In the above polygon scanner,
Recently, high speed and small size have been demanded with the speeding up of laser printers.

[0010]

However, usually,
When the polygon mirror 23 is rotated at a high speed, the polygon mirror 23 is deformed by heat generated by the motor itself, heat generated by air resistance, and expansion due to centrifugal force.

In the conventional polygon mirror 23, since the distance from the screw mounting through hole 23b formed in the axial direction to the reflection surface 23r is reduced with the miniaturization of the polygon mirror 23, the screw tightening torque is reduced. The deformation generated at the tightening portion of the polygon mirror 23 due to the variation is caused by the reflection surface 23r.
There was a problem that it was easier to communicate.

Further, the deformation of the polygon mirror 23 at the time of high-speed rotation is not symmetrical with respect to the axis, and the deformation in each part in the circumferential direction becomes non-uniform. As a result, the deformation due to the distortion of the reflection surface 23r is reduced. There is a disadvantage that it becomes larger.

Therefore, in a conventional laser printer using a polygon scanner, there is a possibility that the printing quality will be degraded when the speed is increased. Further, in the conventional polygon scan, there is a problem that the screw is easily loosened during high-speed rotation.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a polygon scanner which solves the above-mentioned problems which occur in the conventional polygon scanner, and which reduces deformation due to distortion of the polygon mirror during high-speed rotation, and a method of manufacturing the same.

[0015]

To solve the above problems, the present invention employs the following means. In other words, according to the first aspect of the present invention, a rotating body having a cylindrical polygon mirror provided with a plurality of reflecting surfaces for reflecting light and upper and lower surfaces and a flange for attaching the polygon mirror rotates. A polygon scanner for scanning light, wherein a through-hole provided in one of a polygon mirror and a flange portion, and a projection inserted into the through-hole are provided in the other, and an upper surface or a lower surface of the polygon mirror and a flange portion are provided. Are in close contact with each other, and the through holes into which the protrusions are inserted are filled with an adhesive.

According to a second aspect of the present invention, in the first aspect,
The adhesive is characterized by being cured into a plurality of layers along the rotation axis direction.

In the invention of claim 3, according to claim 1 or 2,
, At least one of the projection and the through hole has a conical shape in which the distance between the outer surface of the projection on the side where the flange portion contacts the polygon mirror and the inner surface of the through hole is smaller than the distance in the opening direction. It is characterized by the following.

According to a fourth aspect of the present invention, a columnar polygon mirror having a plurality of reflecting surfaces for reflecting light, and through holes passing through the upper and lower surfaces near the center of the upper and lower surfaces is provided. A polygonal scanner which is fixed to a rotating body having a flange for attaching the polygon mirror, wherein a through hole is provided in one of the polygon mirror and the flange, and the other is provided with the through hole. Providing a protrusion to be inserted into the hole, making the lower surface or upper surface of the polygon mirror closely contact the flange portion, and opening the through hole upward with the protrusion inserted into the through hole, filling with an adhesive, and curing. It is characterized by the following.

According to a fifth aspect of the present invention, in the fourth aspect,
The method is characterized in that the filling of the adhesive and the UV irradiation are repeated a plurality of times.

According to a sixth aspect of the present invention, in the fifth aspect,
The first adhesive is filled at a position where the adhesive comes into direct contact with the surface of the flange portion and flows toward the surface side of the through hole and the projection, and the subsequent adhesive is filled with the previously filled adhesive. It is characterized by being filled by flowing to the surface side of the through-holes and projections at the position directly in contact with the surface of the agent.

[0021]

According to the first to sixth aspects of the present invention, since the polygon mirror is fixed to the flange by the adhesive, the polygon mirror can be stably fixed while suppressing the influence of the distortion on the reflection surface of the polygon mirror. .

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described with reference to embodiments. Here, the structure and mounting of a flange member and a polygon mirror will be mainly described in detail. Therefore, other structures are the same as those in FIG. 1, and the description is omitted.

First, an embodiment according to the present invention will be described with reference to FIG. The rotating body 101 includes a flange 101
a through hole 102a provided in the polygon mirror 102
A projection pin 103 is inserted for insertion into the device. In this case, a mounting hole for fixing the protruding pin 103 is provided in the flange portion 101a, and the mounting hole is fixed by press-fitting or the like, or has an integral structure with the flange portion 101a.

When the rotating body 101 and the polygon mirror 102 are brought into close contact with each other as described above, the projection pins 103 are inserted into the through holes 102a. Therefore, the number of the through holes 102a is equal to or less than the number of the through holes 102a, and the same number of the through holes 102a are provided.

The through hole 102 into which the protruding pin 103 is inserted
The polygon mirror 102 is fixed to the rotator 101 by filling and curing the adhesive a. In addition, this projection pin 1
03 is provided on the flange portion 101a because a through hole was provided on the polygon mirror 102 side. When a through hole was provided on the flange portion 101a, the projection pin was provided on the polygon mirror 102 side as described above. Is provided.

As described above, the adhesive 104 contracts during curing. The polygon mirror 1
02 may be displaced. For this reason, by repeatedly performing the process by dividing and filling the adhesive into a plurality of times, the shrinking force due to one curing of the adhesive is minimized while securing a desired filling amount.

As shown in FIG. 3B, the first adhesive 2
01, a nozzle 202 for injecting an adhesive is arranged so as to directly contact the surface 101b of the flange portion 101a,
After the first adhesive 201 touches the surface 101b of the flange portion, it is caused to flow to the surface side of the through hole and the projection pin 103 (arrow in FIG. 3B).

This prevents the adhesive from first adhering to the surfaces of the through-holes and the protruding pins 103, and the adhesive is not filled up to the surface 101b of the flange portion, thereby preventing the formation of voids. When this gap is formed, the fixing strength between the flange portion 101a and the polygon mirror 102 is reduced, and the fixing position shift of the polygon mirror 102 and the polygon mirror 1
02 may be displaced from the rotating body.

Then, the subsequent (the second or later) adhesive 203 is applied to the surface of the previously cured adhesive (FIG. 3).
In FIG. 3C, the nozzle 202 is arranged so as to directly touch the first adhesive 201 surface, and the adhesive 203
As shown by the arrow in (c), the adhesive flows into the through-holes and the respective surface sides of the protruding pins 103 so that the adhesives come into close contact with each other in the same manner as the relationship between the first adhesive 201 and the surface 101b of the flange portion. Is not formed.

The initial filling amount of the adhesive 201 may be a small amount that does not cause the polygon mirror 102 to be displaced. Therefore, the filling volume is reduced by forming the protruding pin into a conical shape (on the flange side). The distance from the through hole 102a to the outer surface of the projection pin 103 is reduced). Thereby, the contact area between the through hole 102a and the projection pin 103 can be secured even with a small amount. The through hole 102a
May have an inverted conical shape, and the distance from the through hole 102a on the flange portion side to the outer surface of the projection pin 103 may be reduced.

In FIG. 3A, the adhesive 104 is filled and cured a total of four times, but the number of treatments is determined by the filling amount of the adhesive.

[0032]

According to the present invention, it is possible to reduce the deformation of the reflecting surface due to the attachment of the polygon mirror and the deformation due to the distortion of the reflecting surface during high-speed rotation.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an overall structure of a polygon scanner proposed to solve a conventional problem.

FIG. 2 is a schematic top view of a polygon mirror showing a conventional polygon mirror mounting structure.

FIG. 3A is a schematic enlarged sectional view showing a rotating body and a polygon mirror according to a second embodiment of the present invention. (B) It is an outline sectional view showing the first filling method of adhesive concerning a 2nd example of the present invention. (C) It is an outline sectional view showing the method of filling adhesives after the 2nd time concerning a 2nd example of the present invention.

[Explanation of symbols]

101 Rotating body, 102 Polygon mirror, 103 Protruding pin, 104 Adhesive 201 First adhesive, 202 Nozzle, 203 Second adhesive

Claims (6)

[Claims] 1. A light beam is scanned by rotating a rotating body having a columnar polygon mirror provided with a plurality of reflection surfaces for reflecting light and upper and lower surfaces and a flange portion for mounting the polygon mirror. A polygon scanner, wherein a through hole is provided in one of the polygon mirror and the flange portion, and a projection is provided in the other, and the flange portion is in close contact with the upper or lower surface of the polygon mirror, A polygon scanner fixed by an adhesive filled in a through hole. 2. The polygon scanner according to claim 1, wherein said adhesive is hardened into a plurality of layers along a rotation axis direction. 3. A conical shape wherein at least one of the projection and the through hole has a distance between an outer surface of the projection on the side where the flange portion and the polygon mirror are in contact and an inner surface of the through hole is smaller than a distance in the opening direction. The polygon scanner according to claim 1 or 2, wherein: 4. A polygonal mirror having a plurality of reflecting surfaces for reflecting light, upper and lower surfaces, and a through-hole penetrating the upper and lower surfaces near the center, wherein the lower surface or the upper surface is in contact with the polygon mirror. A method of manufacturing a polygon scanner to be fixed to a rotating body having a flange portion for mounting a mirror, wherein a through hole is provided in one of the polygon mirror and the flange portion, and a projection inserted into the through hole is provided on the other. A polygon, characterized in that the lower surface or upper surface of the polygon mirror is brought into close contact with the flange portion and the projection is inserted into the through hole, and the through hole is opened upward, filled with an adhesive, and cured. Scanner manufacturing method. 5. The method according to claim 4, wherein the filling of the adhesive and the UV irradiation are repeated a plurality of times. 6. The first adhesive is filled at a position where the adhesive comes into direct contact with the surface of the flange portion and flows toward the surface side of the through hole and the projection, and the subsequent adhesive is filled at the front. 6. The method according to claim 5, wherein the adhesive is filled at a position in direct contact with the surface of the adhesive filled into the through hole and by flowing toward the surface of the through hole and the projection. .