JPS5815650B2 - Kaitenkoutai - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotating structure, and more particularly to a rotating structure suitable for application to a deflector that deflects a light beam such as a laser beam using a rotating polygon mirror.

Generally, in order to polarize a light beam such as a laser beam,
As shown in FIG. 1, a rotating polygonal mirror 8 having a large number of mirror surfaces 6 arranged on its outer circumference is mounted on the rotating shaft 4 of the motor 2, and while rotating the motor 2 at high speed in the direction of arrow a, a laser light source is 10, a polarizer is used which is configured to deflect the reflected beam 14 reflected by the mirror surface 6 in the direction of the arrow by applying the laser beam 12 to the outer circumference of the rotating polygon mirror 8. In this case, In order for the spot of the reflected beam 14 reflected and deflected by each mirror surface 6 of the polygon mirror 8 to reach the target point correctly, each mirror surface 6 must be mounted exactly parallel to the rotation axis 4 of the motor 2 to prevent surface deflection. It is required that there be no

According to the current processing technology, it is possible to obtain sufficiently high precision inclination of each mirror surface 6 with respect to the lower surface of the mirror body with the rotary polygon mirror 8 alone, in view of the polishing accuracy of the optical equipment. The flange surface A of the flange 16 for placing the rotary polygon mirror 8 concentrically and accurately at right angles to the rotation axis 4 of the motor 2 can be It is possible to make the flange surface A perpendicular to the rotation axis 4 with relatively high precision by cutting and polishing the flange surface A while rotating the flange surface A, thereby suppressing the runout of the flange surface A. It is.

However, even if the rotating polygon mirror 8 and the flange surface A are provided with highly accurate surface inclination and surface deflection suppressed, alignment cannot be achieved to ensure that the bottom surface of the rotating polygon mirror 8 is pressed against the flange surface A. Otherwise, each mirror surface 6 of the polygon mirror 8 would be tilted with respect to the rotation axis of the motor 2, causing vibration.

On the other hand, generally the flange 1 is
6 is press-fitted onto the rotating shaft 4 of the motor 2, the rotating polygon mirror 8 is placed so that its lower mounting surface B is in contact with the flange surface A, and then the rotating polygon mirror 8 is placed at three locations on the lower surface from the center of the rotating shaft 4. A pressing plate 20 having pressing pieces 18 arranged at equal distances at an angle of 120° in the circumferential direction is mounted, and the suppressing plate 20
Attach the nut 22°2 with the threaded part provided at the top of the flange 16.
4 to press the lower mounting surface B of the rotary polygon mirror 8 onto the flange surface A so that the mirror surface 6 of the rotary polygon mirror 8 is parallel to the axis of the rotating shaft 4. A configuration is adopted in which the mirror surface 6 is held in place to prevent surface wobbling of the mirror surface 6.

However, when pressing the pressing plate 20 directly with the nut 22,
If the nut 22 is tilted with respect to the pressing plate 20 due to manufacturing errors or other causes, the nut 22 will come into partial contact with the pressing plate 20 as shown in the second figure, and the pressing force F will be lower than the pressing plate 20. 20, the lower mounting surface B of the rotary polygon mirror 8 is not pressed sufficiently against the flange surface A in some parts, and the lower mounting surface B and flange surface A are pressed against the flange surface A in places where the pressure is weak.
Due to the influence of elastic bodies such as dust caught between them or other factors, a slight gap △X of several tenths of a micrometer is created between the lower mounting surface B of the rotating polygon mirror 8 and the flange surface A. This may result in the mirror surface 6 of the rotating polygon mirror 8 causing a surface deflection of several seconds in terms of angle.

Therefore, an object of the present invention is to eliminate the drawbacks of the above-mentioned prior art, and to solve the problem of mounting a rotating body such as a rotating polygon mirror at right angles to a flange surface that is kept perpendicular to the axis of a rotating shaft of a motor, etc. (Regarding a suitable rotating structure) More specifically, the purpose of the present invention is to reduce the pressing force applied by the tightening fitting to the entire surface of the rotating body when tightening the rotating body to the flange surface mounted perpendicularly to the rotating shaft. It is an object of the present invention to provide a new rotating structure that can correctly position a rotating body with respect to a flange surface by configuring it to work uniformly.

Hereinafter, the present invention will be explained in more detail with reference to the drawings. FIG. 3 is a longitudinal cross-sectional view of a rotating structure according to an embodiment of the present invention, and FIG. Fifth
The figures each show a perspective view of a presser ring part which is a pressing force transmitting part in the configuration shown in the third diagram, 2 is a motor that rotates at high speed, 4 is a rotating shaft of the motor, and 16 is the rotating shaft 4.
a flange having a flange surface A perpendicular to the axis of the
Reference numeral 8 indicates a rotary polygon having a lower mounting surface B that abuts against the flange surface A. Reference numeral 20 indicates a rotary polygon having a lower mounting surface B that abuts against the flange surface A. Reference numeral 20 indicates a rotary polygon that abuts on the upper surface of the rotary polygon mirror 4 at three locations equidistant from the center of the rotating shaft 4 and at intervals of 120° in the circumferential direction. The pressing plate 30 having the suppressing piece 18 in contact with it is formed in a ring shape concentric with the rotating shaft 4, and has a spherical protrusion 26 on a line passing through the center of its lower surface, and a spherical protrusion 26 on the line passing through the center of its upper surface. A presser ring (transmission member) for transmitting pressing force formed by forming a spherical protrusion 28 on a perpendicular line, 22
To! A nut (pressing means) that tightens and presses the retaining ring 30 toward the pressing plate 20 with a threaded portion provided on the upper part of the flange 16, and 24 a locking nut to prevent the nut 22 from loosening. They are shown below.

In the above-described configuration, by tightening the nut 22 screwed into the threaded portion provided on the upper part of the flange 16, the protruding portion 28 of the retaining ring 30, the retaining ring 30, the protruding portion 26 of the retaining ring 30, and the pressing Plate 20, pressing piece 18
Press the upper surface of the rotating polygon mirror 8 through the rotating polygon mirror 8.
The lower mounting surface B of is pressed against the flange surface A.

Now, as shown in FIG. 4, when the nut 22 is tilted with respect to the pressing plate 20 and applying a pressing force F, the pressing force F is always between the shaft connecting the protruding parts 28 of the pressing ring 30 and the protruding parts 26. This force acts on the intersection of the axes connecting the two, that is, the center of the rotating shaft 2, and this force applies pressing forces of fl and f2 to the pressing plate 20 via the protrusion 26, and the pressing force of the pressing plate 20 is A pressing force F is applied to the center.

Since this pressing force F is applied as a uniform pressing force f3 to the pressing piece 18, the rotating polygon mirror 8 is pressed from its upper surface with a uniform force, and the mounting lower surface B of the polygon mirror 8 is attached to the flange 18. It will be pressed uniformly against the flange surface A.

Therefore, the rotating polygon mirror 8 can be reliably and stably attached to the flange 16, and can therefore be fixed to the rotating shaft 4 of the motor 2 without tilting.
The mirror surface 6 can be mounted accurately in parallel.

Note that the retaining ring 30 does not necessarily have to have its protruding portions 26 and 28 formed in a hemispherical shape as shown in FIG. It may also be formed into a semi-cylindrical shape.

FIG. 1 is a block diagram of a rotating structure according to another embodiment of the present invention, in which a is a plan view and b is a longitudinal sectional view taken along line X-X.

In the figure, reference numeral 32 denotes a gimbal spring configured such that the longitudinal extension lines of joints A220 and H2 are perpendicular to each other at the center, as shown in FIG. From the ring 40 to the fitting C, through the inner ring 42
It is structured so that it can be transmitted to

In the configuration shown in FIG. 1, the pressing plate 20 is made to correspond to the inner ring 42 of the gimbal spring 32,
A tightening ring 34 is made to correspond to the outer ring 40 of the gimbal spring 32, and by tightening the tightening ring 34 to the flange 16 with screws 36, the pressing piece 18 of the pressing plate 20 is tightened. Then, the rotating polygon mirror 8 is attached to the flange 16.
By pressing the flange surface with a uniform force, the rotating polygon mirror 8 can be fixed to the rotating shaft 4 of the motor 2 through the flange 16 without tilting.

In the configuration shown in FIG. 1, the outer ring 40 of the gimbal spring 32 is made to correspond to the tightening ring 34, and the inner ring 42 and the pressing plate 20 are made to correspond to each other. The same effect can be obtained by making the ring 40 correspond to the pressing plate 20 and by making the inner ring 42 correspond to a nut that engages with a threaded portion provided at the upper part of the flange 16.

In each of the above embodiments, a case has been described in which the rotating structure of the present invention is applied to a polarizer that polarizes a light beam such as a laser beam using a rotating polygon mirror. Examples include, but are not limited to, various types of rotating bodies, such as cutters with rotary round blades, polishing dies for precision machining, and all other rotating bodies whose surface runout during rotation poses a major obstacle to their use. No application is possible.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the configuration of a general polarizer, FIG. 2 is a longitudinal cross-sectional view of a conventional rotating structure applied to a polarizer, and FIG. 3 is a rotating structure according to an embodiment of the present invention. FIG. 4 is a partial side view of the suppressing plate portion shown in the third drawing, FIG. 5 is a perspective view of the pressing ring portion shown in the third drawing, and FIG.
The figure is a perspective view showing another configuration example of the third illustrated pressing ring part,
FIG. 7 is a plan view (a) and a longitudinal cross-sectional view (b) taken along the line X-X of a rotating structure according to another embodiment of the present invention applied to a polarizer.
1. FIG. 8 is a perspective view of a gimbal spring applied to the configuration shown in the first diagram. 2... Motor, 4... Rotating shaft, 6...
...Mirror surface, 8...Rotating polygon mirror, 16...
...Flange, 20...Press plate, 22...
...Nut, 30...Press ring, 32...
...Jin/NJ Ruhane.

Claims (1)

[Claims] 1. A flange having a plane perpendicular to the rotation axis and fixed to the rotation axis, a rotating body placed in contact with the plane, a suppressing means for pressing the rotating body toward the flange, A pressing force is applied from the suppressing means through two points which are interposed between the suppressing means and the rotating body and are arranged symmetrically about the rotation axis, and a pressing force is applied from the suppressing means through two points arranged symmetrically about the rotation axis at points other than the two points. A rotating structure characterized by comprising a transmission member that transmits and applies the pressing force to a rotating body through two symmetrically arranged points.