JP2569216B2 - Rotating polygon mirror - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a rotating polygon mirror used in a laser printer or the like, and a balance weight for preventing unbalance vibration when rotating the rotating polygon mirror is rotated at a high speed. The present invention relates to a rotary polygon mirror provided with concave grooves and holes for the purpose of preventing scattering due to scatter.

[Conventional technology]

As described in Japanese Patent Publication No. Hei 1-252730, the conventional device simply forms a balance weight mounting groove for mounting the balance weight in an annular shape so that the rotational balance can be easily adjusted. Therefore, the centrifugal force of the balance weight becomes large and the balance weight tends to be separated and scattered, and its prevention is not considered.

[Problems to be solved by the invention]

The above prior art is a simple groove, and when a balance weight is mounted, it is not determined whether the balance weight is mounted on the outer circumference side, the inner circumference side, or the middle of the groove bottom face. , And the centrifugal force of the balance weight has increased, and separation and scattering have become a problem. Therefore, there is a possibility that the balance weight attached to the middle or the inner peripheral side of the conventional groove may come off, which may cause imbalance during rotation.

SUMMARY OF THE INVENTION An object of the present invention is to prevent separation and scattering of a balance weight.

[Means for solving the problem]

In order to achieve the above object, a circumferential groove provided on the upper surface of the rotary polygon mirror, a plurality of grooves provided intermittently, and a plurality of concave holes have a deep outer peripheral portion and a shallow inner peripheral portion. It was done.

[Action]

As the balance weight, an adhesive or the like having a large specific gravity is used, or a method of bonding the weight is used. Therefore, when the rotating polygon mirror is held horizontally and the adhesive for the weight is dropped into the groove, since the outer periphery of the groove is deep, the adhesive always flows to the outer peripheral side, and the outer peripheral side wall is formed. It will be in close contact with. Also, when the weight is bonded, it can be bonded to the groove deeper, that is, shifted to the outer peripheral side of the groove, by inserting the weight into the groove and pressing it from above.

Even when centrifugal force is applied to the balance weight by the balance weight being in close contact with the outer peripheral wall as described above,
Does not scatter.

In the same way, it is necessary to disperse the weights in intermittent grooves and concave holes as well,
There is the above effect.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1, 2, and 3. FIG.

1 and 2, a rotary polygon mirror 3 is fixed to a motor shaft 2 protruding from the motor 1. On the upper surface of the rotary polygon mirror 3, a balance weight mounting groove 4 is provided.
As shown in the figure, the outer peripheral side is deep and the inner peripheral side is shallow.

With the above configuration, when the rotating part of the motor 1 integrated with the rotating polygon mirror 3 is rotated, vibration is generated due to rotational imbalance. To reduce this rotational vibration,
Adjust the balance.

Balance adjustment is an operation of attaching a rotating part to a machine, detecting the position and amount of unbalance, and attaching a balance weight.

The balance weight 5 is made of an adhesive having a large specific gravity and
The method of fixing a metal having a large specific gravity with an adhesive is favorable because there is no scratch on the mirror surface due to the chips rather than cutting and drilling with a drill tube.

When the balance weight 5 is mounted, the rotating polygon mirror is held horizontally, and the required amount of the balance weight 5 is dropped into the balance weight mounting groove 4 from above. The balance weight 5 dropped into the balance weight mounting groove 4 flows to the bottom of the groove, that is, to the outer peripheral side of the balance weight mounting groove 4, and adheres to the outer peripheral wall 7 to fix the adhesive in this state.

The balance weight 5 fixed as described above is in close contact with the outer peripheral wall 7 even when centrifugal force is applied to the balance weight 5 when the rotating polygon mirror is rotated at a high speed and the balance weight 5 is likely to fly outward. Therefore, the vehicle can be operated with low vibration without changing the rotational balance during operation.

4 and 5 show deformations of the balance weight mounting groove 4; FIG. 4 shows a plurality of intermittent balance weight mounting grooves 4 ', and FIG. 5 shows a balance weight mounting hole 6; The outer peripheral portion is deep and the inner peripheral portion is shallow, so that when the balance weight 5 is mounted, it is mounted on the outer peripheral side, so that separation and scattering due to centrifugal force of the balance weight 5 can be prevented during operation.

〔The invention's effect〕

According to the present invention, the balance weight 5 is in close contact with the outer peripheral wall 7 of the balance weight mounting groove 4, and even if the rotating polygon mirror is rotated at a high speed, the balance weight 5 does not separate and scatter, and the rotational balance is maintained. It can be operated with low vibration without changing.

Also, the balance mounting groove 4, the plurality of intermittent balance wit mounting grooves 4 ', and the balance weight mounting hole 6 can be manufactured inexpensively and easily by plastic working, that is, press working.

[Brief description of the drawings]

FIG. 1 is a top view of a rotary polygon mirror including a motor according to one embodiment of the present invention, FIG. 2 is a front view of a rotary polygon mirror including a motor according to one embodiment of the present invention, and FIG. FIG. 4 is a side sectional view of the rotary polygon mirror of the embodiment, FIG. 4 is an inclined top view of the rotary polygon mirror of a modified example of the present invention, and FIG. 5 is a top view of the rotary polygon mirror of a modified example of the present invention. 1 ... Motor, 2 ... Motor shaft, 3 ... Rotating polygon mirror, 4 ... Balance weight mounting groove, 5 ... Balance weight, 6 ... Balance weight mounting hole, 7 ... Wall.

Claims (4)

(57) [Claims] In a rotary polygon mirror for reflecting a light beam such as a laser beam so as to scan, an annular balance weight mounting groove is provided on the upper surface of the rotary polygon mirror. A rotating polygon mirror whose shallow side is formed circumferentially. 2. A rotary polygon mirror according to claim 1, wherein a plurality of circumferentially deep grooves are provided on the upper surface of said rotary polygon mirror in an intermittent manner. 3. The rotary polygon mirror according to claim 1, wherein a plurality of concave outer peripheral holes are provided on the upper surface of the rotary polygon mirror. 4. The groove of claim 1, the plurality of intermittent grooves of claim 2, and the plurality of concave holes of claim 3 are formed into a concave shape by plastic working, that is, press working. A rotating polygon mirror characterized by the following.