JPS60172016A - Holo-scanner - Google Patents

Abstract

PURPOSE:To clamp easily the upper flange, and to install correctly a hologram disk to the lower flange by making the inter-bottom face distance of the outside peripheral stepped part of the projecting surface of each flange smaller than the sum of the size of thickness of the hologram disk and the free diameter of a rubber ring, when clamping each upper and lower flange faces whose diameter section is roughly a projecting shape. CONSTITUTION:As for each upper and lower flange 30, 10, its diameter section is formed in roughly a projecting shape, and a circular stepped part 10b and a circular stepped part 30b are formed on the outside periphery of a projecting surface of the lower flange 10, and the outside periphery of a projecting surface 30a of the upper flange 30, respectively. Also, the center hole of a hologram disk H, and a rubber ring R whose section is round are fitted into the stepped part 10b and the stepped part 30b, respectively. In this case, a distance between a bottom face 30c of the stepped part 30b and the projecting surface 30a, a distance between a bottom face 10c of the stepped part 10b and the projecting surface 10a, a thickness of the disk H, and a free diameter of the rubber ring R are denoted as t1, t2, t3 and (d), respectively, and set to a relation of t1+t2<t3+d. In such a way, the rubber ring R is deformed elastically and the disk H is fixed to the lower flange 10.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a holoscanner, and more particularly to a holoscanner that can be applied to optical writing scanning of a laser printer.

(Prior Art) Conventionally, in a holoscanner, a hologram disk is mounted on a motor shaft by placing the hologram disk on a lower flange fixed to the motor shaft and tightening the hologram disk from above with the upper flange.

To give an example, in FIG. 1, the lower flange 1 is fixed to the shaft M1 of the motor M by gluing, press-fitting, using a key, or other appropriate means for preventing rotation, and the hologram disk H is centered on the outer step of the lower flange 1. It is inserted into the hole and placed, and further tightened from above with bolts 4 set at equal intervals on the circumference by the upper flange 3 via the annular synthetic resin plate 2. Through such a tightening means, the hologram disk H't''
- It will be rotated in one direction with the motor shaft M1. .

In this type of tightening means, a certain amount of tightening force is required to prevent the hologram disk from slipping with respect to the motor shaft M1, but when tightening the bolt 4, the force almost overcomes the elasticity. Since the hologram disk H is directly affected through the synthetic resin plate 2, which does not have the same structure, large distortion occurs in the disk, which seriously affects its optical characteristics. Therefore, during assembly, special consideration must be given to the magnitude of the tightening torque so that the tightening force at the circumferential portions of the bolts 4 is equalized.

Furthermore, depending on the precision of the parts, the problem may occur at various parts of the circumference, making assembly complicated.

(Objective) Therefore, the object of the present invention is to
To provide a holoscanner in which a hologram disk can be properly attached to a lower flange without requiring special consideration to the tightening force.

(tI formation) The configuration of the present invention will be described below based on one embodiment.

In this example, as shown in FIG. 2, the upper flange 3° and the lower flange 10 each have a substantially convex diameter cross section. On the outer periphery of the convex surface 10a of the lower flange 10, there is a circular step 101) on the outer periphery of the upper flange 3.
A circular step portion 30b is also formed on the outer periphery of the convex surface 30a.

The center hole of the hologram disk H is fitted into the stepped portion 10b, and a rubber ring R having a circular cross section is fitted into the stepped portion 30b.

Here, the distance between the bottom surface 30c of the stepped portion 30b and the convex surface 30a is tI + the distance between the bottom surface 10c of the stepped portion lob and the convex surface 10
If the distance from a is 12 + the thickness of the hologram disk H is ts + the diameter of the rubber ring H when it is not deformed by external force, the so-called free diameter is d, then t, -1-t2<
The relationship is set as ts-1-d.

Thus, when the upper flange 3o is tightened to the lower flange 1o with the bolts 4, a certain tightening limit is reached when the convex surfaces 1oa and 3oa come into close contact.

At this time, the above t+ 10"t < ts 1d
Due to the round size relationship, the rubber ring R is elastically deformed and the hologram disk H is fixed to the lower flange 1o.

Here, the elastic force accompanying the deformation of the rubber ring acts uniformly on each annular portion of the rubber ring and presses the hologram disk H. Setting the magnitude of this elastic force within a range that does not cause slippage between the hologram disk H and the lower flange 10 and does not adversely affect the optical properties is important due to the diameter of the rubber ring H and the rubber・This can be easily done by selecting a suitable quality.

According to experiments, as shown in Figure 3, when using a rubber ring with a diameter of 6M, t, the minimum bolt tightening torque that does not cause slippage is 1.5νf, Cm, and the deformation of the rubber ring. Distortion that adversely affected optical properties occurred when the amount exceeded about 1.7 yen. Therefore, the possible tightening range is from 0.25 to 1.7 in terms of the amount of compression of the rubber ring, which is quite wide.

It can also be seen that the bolt tightening torque corresponding to this amount of compression also ranges over a wide range.

Therefore, in the present invention, if the bolts are tightened until the convex surfaces 10a and 3oa come into contact with each other, the hologram disk H is automatically held by the deformation of the rubber ring with a force that does not cause slippage and does not adversely affect the optical characteristics. becomes possible.

In this example, the balancing screw holes 6, which were conventionally formed in the lower flange 1, are formed in the upper flange 30.

This is because the hologram disk H has variations in thickness, and in order to avoid fluctuations in the recording surface due to this variation, the screw 6 is machined so that the hologram recording surface is aligned with the bottom surface, which is the mounting reference surface of the disk. This is to eliminate the problem that the hologram recording surface could be damaged due to tool interference.

(Effects) According to the invention, the range of appropriate bolt tightening force is expanded, which improves the workability of assembling the holoscanner, and prevents distortion of the hologram disk that adversely affects optical properties and slippage with the motor shaft. This problem is eliminated, which is convenient.

[Brief explanation of the drawing]

lO...Lower flange, 3o...Upper flange, lO
a, 30a...convex surface, 10b, 3ob'' step,
10c, 30c... bottom. Most 1 U1

Claims (1)

[Claims] In a holo scanner in which a hologram disk is mounted on a lower flange fixed to a motor shaft and the disk is mounted by tightening the upper flange from above, each of the upper and lower flanges has a substantially convex diameter cross section. When the convex surfaces of each flange are tightly opposed and tightened, the distance between the bottom surfaces of the convex outer circumferential stepped portion of each flange is determined by the thickness of the hologram disk attached to the stepped portion via the rubber ring. Holoscanner characterized by being set smaller than the sum of the free diameter of the.