JPH0534622A - Deflecting scanner - Google Patents

Abstract

PURPOSE:To miniaturize a housing by fixing the housing to an optical case with a spring, and to reduce the cost by reducing the weight and decreasing the number of parts. CONSTITUTION:A flange 12 is subjected to press fitting to a rotation axis 11, a rotary polygon mirror 13 is placed on the flange 12, a yoke 14 is fixed under the flange 12, a driving magnet 15 is fixed onto the inside surface of the yoke 14, and it is opposed to a stator coil 16 placed in the lower part, by which a driving motor is constituted. Also, the rotation axis 11 is fitted into an inner races of a ball bearing 18 subjected to press fitting into a housing 17. The housing 17 is fitted into a hole part of an optical case 19, and a compression coil spring 20 is interposed between the optical case 19 and the lower part. The compression coil spring 20 presses the lower flange 17b in the A direction, therefore, the lower face of the upper flange 17a is pressed against the optical case 19, and the housing 17 is fixed to the optical case 19. Accordingly, since the housing 17 is fixed with the spring 20, the housing can be miniaturized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deflection scanning device such as a laser beam printer using a rotating device supported by a ball bearing or the like.

[0002]

2. Description of the Related Art Heretofore, precise ball bearings have been used in rotating devices for performing high-speed or high-precision rotation, particularly in laser beam printers and the like.

FIG. 5 shows a conventional example of a deflection scanning device of a laser beam printer. A flange 2 is press-fitted into the rotary shaft 1, a rotary polygon mirror 3 is placed on the flange 2, and a yoke 4 is fixed below the flange 2. Further, a drive magnet 5 is fixed to the inner surface of the yoke 4, and constitutes a drive motor together with the stator coil 6 installed opposite to the rotary polygonal mirror 3 via the rotary shaft 1 for rotation. The rotary shaft 1 is fitted into the inner ring of a ball bearing 8 press-fitted in the housing 7, and the housing 7 is fixed to the optical box 10 by screws 9.

[0004]

However, in the above-mentioned conventional example, the screw 9 is used to fix the housing 7 to the optical box 10, so that the screw 9 is prevented from hindering the rotation of the yoke 4. Are arranged outside the yoke 4. Therefore, the housing 7 becomes large in size, which causes a weight increase or a cost increase. Further, since 4 to 5 screws 9 are normally used, the number of parts, the number of steps, or the cost increases.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and to provide a lightweight and inexpensive deflection scanning device by eliminating the use of screws and downsizing the housing.

[0006]

A deflection scanning apparatus according to the present invention for achieving the above object includes a deflector for deflecting and scanning a light beam by rotating a drive motor supported by a bearing, and a deflector for scanning the light beam. In a deflection scanning device in which a means for collecting light on a scanning body is housed in a container, the housing of the drive motor is fixed to the container via an elastic member.

[0007]

In the deflection scanning device having the above-described structure, the housing containing the ball bearing is arranged in the optical box, and the elastic member is fitted into the concave portion provided under the housing to fix the housing and the optical box.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the embodiments shown in FIGS. FIG. 1 is a sectional view showing a first embodiment. A flange 12 is press-fitted into the rotary shaft 11, a rotary polygon mirror 13 as an example of a deflector is mounted on the flange 12, and a yoke 14 is fixed below the flange 12. Further, the driving magnet 1 is provided on the inner surface of the yoke 14.
5 is fixed and the stator coil 16 placed below
And constitutes a drive motor facing the above. Furthermore, the rotating shaft 1
1 is a ball bearing 1 press-fitted in a housing 17
It is fitted in the inner ring of 8.

A metal member such as brass is usually used for the housing 17, and an upper flange 17a and a lower flange 17b are integrally molded. The housing 17 is fitted in the hole of the optical box 19, and the compression coil spring 20 is interposed between the optical box 19 and the lower part.

This compression coil spring 20 has a lower flange 1
Since 7b is pressed in the A direction, the lower surface of the upper flange 17a is pressed against the optical box 19, and the housing 17 is fixed to the optical box 19. The outer diameters of the upper flange 17a and the lower flange 17b may be slightly larger than the body diameter B of the housing 17.

As described above, in this embodiment, the compression coil spring 20 is used to fix the housing 17 to the optical box 19.
Since the use of the screw eliminates the need for screws, it is possible to reduce the size and weight of the housing 17, or to reduce the cost. Further, the number of parts and the number of processes can be reduced.

FIG. 2 is a sectional view showing a second embodiment.
Instead of the compression coil spring 20 of the first embodiment described above, an elastic sleeve 21 made of resin, rubber or the like is used, and it is compressed between the optical box 19 and the lower flange 17b. Is attached to. Sleeve 21
Presses the lower flange 17b in the A direction as in the first embodiment, so that the housing 17 is pressed and fixed to the optical box 19.

FIG. 3 is a sectional view showing a third embodiment.
A projection 22 having elasticity is integrally formed with the optical box 19 on the lower surface of the molded optical box 19. When the housing 17 is fixed to the optical box 19, the protrusion 22 is bent while opening outward, and the lower flange 17b is pressed in the direction A while returning. Therefore, the housing 17 is pressed and fixed to the optical box 19. .

In this embodiment, the same effects as those of the first and second embodiments described above can be obtained, and the elastic members such as the compression coil spring 20 and the sleeve 21 used in the further embodiments can be omitted. Therefore, further cost reduction can be achieved.

FIG. 4 is a sectional view showing the fourth embodiment, and the lower flange 17b of the above-mentioned first to third embodiments.
Instead of having the above, the outside of the lower part of the housing 17 is molded with the housing 17 and is elastic.
3 is provided.

In this case, the elastic foot 23 bends,
Since the foot 23 presses the housing 17 in the A direction,
The housing 17 is fixed to the optical box 19.

[0017]

As described above, the deflection scanning device according to the present invention serves as means for fixing the housing to the optical box.
Since the elastic member is used instead of the screw, the housing can be downsized, the weight and the number of parts can be reduced, and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of a first embodiment.

FIG. 2 is a sectional view of a second embodiment.

FIG. 3 is a sectional view of a third embodiment.

FIG. 4 is a sectional view of a fourth embodiment.

FIG. 5 is a cross-sectional view of a conventional example.

[Explanation of symbols]

11 rotation axis 13 rotating polygon mirror 17 housing 17a Upper flange 17b Lower flange 19 Optical box 20 compression coil spring 21 Sleeve 22 protrusion 23 feet

Claims (6)

[Claims] 1. A deflection scanning apparatus in which a deflector for rotating a drive motor supported by a bearing to deflect and scan a light beam and a means for condensing the light beam on an object to be scanned are housed in a container. A deflection scanning device, wherein a housing of a drive motor is fixed to the container via an elastic member. 2. The deflection scanning device according to claim 1, wherein a member supporting a bearing of the drive motor fixes the container by an elastic member. 3. The deflection scanning device according to claim 1, wherein the elastic member is a coil spring. 4. The deflection scanning device according to claim 1, wherein the elastic member is formed of resin or rubber. 5. The deflection scanning device according to claim 1, wherein the elastic member is integrally molded with the container. 6. The deflection scanning device according to claim 1, wherein the elastic member is provided outside the storage container.