JPH0664815B2 - Optical read / write device stabilizer - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a stabilizer for preventing vibration of an information recording disc or the like when reading or writing an optical information recording disc such as a compact disc or a laser disc. is there.

[Conventional technology]

In recent years, some optical read / write devices have been used in place of magnetic recording devices. For example, as shown in FIG. 3, the structure of a compact disc player (hereinafter referred to as a CD player) is such that a disc 1 on which information is recorded by a number of irregularities called pits 1a is rotated by a motor 2 while the disc 1 is rotated. The surface on which the pits 1a are formed is irradiated with a laser beam, and the reflected light is detected by the head 3 which is movable in the radial direction of the disk 1 to read information. Since this disc 1 is recorded at a very high density, the irradiation position of the laser beam may be displaced when the surrounding vibration is transmitted, and the information may be erroneously read. Therefore, it has been attempted to prevent the vibration by placing a spacer or a plate made of a material having a large vibration damping property under the CD player.

Further, other optical reading / writing devices such as laser discs and CD-ROMs have almost the same structure.

[Problems of conventional technology]

However, in the above-mentioned optical reading / writing apparatus, since the information recording disk is generally supported only by the central portion, the vibration of the information recording disk itself cannot be prevented. For example, in the case of a CD player, as shown in FIG. 2 (a), the eccentricity phenomenon in which the center shifts by Δx when the disc 1 rotates, and as shown in FIG. A wavy phenomenon in which the portion vibrates in a wavy shape with a width of Δy occurred. Therefore, the position of the pit 1a formed on the disc 1 is slightly changed, and there is a high possibility that information may be erroneously read, resulting in inconvenience such as poor sound quality. Also in other optical reading / writing devices, similarly, due to the vibration of the information recording disk, errors are likely to occur during reading or writing of information, and there is a problem that the image and sound quality are distorted.

[Means for solving problems]

In view of the above, the present invention is mounted on one side of an information recording disk used in an optical reading / writing apparatus, and a disk-shaped body is formed of ceramics to prevent vibration of the information recording disk, and the disk is formed. A stabilizer for an optical reading / writing device, in which a mounting hole is provided in the central portion of the sheet, is used.

〔Example〕

A CD stabilizer S according to an embodiment of the present invention is a disk-shaped body made of ceramics having a center mounting hole S ₁ as shown in FIG. 1 (a), and has an outer diameter substantially the same as that of the disk 1. Further, 'a disc-shaped body made of ceramics having a _1, stabilizer S for Do CD small diameter than the disc 1' central mounting hole S as shown in FIG. 1 (b) may be used. These CD stabilizers S, S'can be simply mounted on the CD player while being placed on the upper surface of the disc 1, and are easy to operate and can be used for general CD players. Further, a mechanism may be provided in which the CD stabilizers S and S'are built in the CD player in advance and automatically placed on the upper surface of the disc 1.

As Table 1 shows the characteristic table of brass and various ceramics, ceramics has a large Young's modulus and a small specific gravity, and therefore has a large vibration damping characteristic. Also CD
Since the natural frequencies of the disk stabilizers S and S'are different from those of the disk 1 and they also cancel each other's vibrations, by placing the CD stabilizers S and S'on the upper surface of the disk 1, the disk 1 It is possible to reduce the external vibration transmitted to and stabilize the rotation.

Next, as a stabilizer S for such a CD, the diameter is
120 mm, the center mounting hole S _{1 has} a diameter of 15 mm and the same outer diameter as the disk 1 having a thickness of 0.5 mm, and the stabilizer S ′ for CD has a diameter of 48 mm and the center mounting hole S ′ _{1 has} a diameter of 15 m.
Two prototypes were made of alumina ceramics, each of which had a diameter of 0.4 times that of the disk 1 having a thickness of 0.5 mm and a thickness of 0.5 mm. As a comparative example, a CD stabilizer made of brass having the same outer shape as that of the disc 1 was prepared, and the eccentricity Δx and the wavy Δy of the disc 1 when the respective CD stabilizers were used were measured. The ratios to those without the CD stabilizer were as shown in Table 2, respectively.

From Table 2, a metal stabilizer for CD was used.
The eccentricity of NO.2 could be reduced to only 70% and the waviness could be reduced to about 75%, whereas that of No.3, which was made of alumina ceramics and used a CD stabilizer with the same external shape as disk 1. Was able to reduce the eccentricity to 50% and the waviness to about 45%. Also, a CD made of alumina ceramics and having a diameter 0.4 times that of the disk 1.
The eccentricity is 50 for the No. 4 using the stabilizer for
%, Waviness can be reduced to around 55%, N
The effect is similar to that of o.3.

As a result, the diameter of the stabilizer for CD is 0.
It turns out that about 4 times is enough.

Alumina ceramics was used as the ceramics forming the CD stabilizer 1, but ceramics such as zirconia, silicon carbide, and silicon nitride also have a high Young's modulus, and therefore equivalent vibration prevention is achieved. It worked.

In addition, the CD stabilizers S and S ′ have a surface roughness in order to have adhesiveness when placed on the upper surface of the disc 1.
Those of 6s or less were effective.

In the above embodiments, only the stabilizer for CD has been described, but also in other optical reading / writing devices, if a stabilizer having a size corresponding to each information recording disk is used, the vibration of the information recording disk is prevented. It can prevent and stabilize the rotation.

〔The invention's effect〕

As described above, according to the present invention, the information recording disk used in the optical reading / writing device is mounted on one side,
In order to prevent vibration of the information recording disk, a disk-shaped body is formed of ceramics, and an optical read / write device stabilizer having a mounting hole at the center of the disk-shaped body is used to record information with a simple operation. Vibration of the disk can be prevented, rotation can be stabilized, and higher quality screens and sounds can be played and recorded.
Further, since there is less risk of making an error during reading and writing of information, it is possible to provide a stabilizer for an optical reading and writing apparatus having many features so that information of higher density can be recorded.

[Brief description of drawings]

FIGS. 1 (a) and 1 (b) are perspective views showing a state in which the optical stabilizer according to the present invention is applied to a CD player and the optical stabilizer for CD is placed on the upper surface of the disc, respectively. (A) is a perspective view showing an eccentricity phenomenon of a disc, (b) is a perspective view showing a wavy phenomenon of a disc, and FIG. 3 is a side view showing a schematic structure of a CD player. S, S ′: Stabilizer for CD 1: Disc 2: Motor 3: Head

Claims (1)

[Claims] 1. An information recording disk used for an optical reading / writing apparatus, which is mounted on one side of the disk to form a disk-shaped body made of ceramics for preventing vibration of the information recording disk and a center of the disk-shaped body. A stabilizer for an optical reading / writing device, which is characterized in that a mounting hole is formed in the portion.