KR19990041470A - Disc record carrier - Google Patents

Abstract

The present invention relates to a disc recording medium which minimizes vibration by preventing buckling.

The disc recording medium of the present invention has a clamp portion formed in a shape protruding in the center of the disc and incorporating heat insulating means.

Description

Disc record carrier

The present invention relates to a disc recording medium, and more particularly, to a disc recording medium which minimizes vibration by preventing buckling.

In recent years, discs have been required to be large-capacity, and as an example, a commercially available magneto-optical disc records about 650MB of information on a 120mm outer diameter disc such as a compact disc (hereinafter referred to as "CD"). It will be able to play and play, and is expected to grow to 6GB to 14GB in the future. In addition, a recording method using magnetic field modulation using a magnetic head is adopted for recording, and a method of detecting a change in polarization angle according to a photo-magnetic conversion characteristic by using a photoelectric element during reproduction is adopted. In the process of recording information, the magnetic head records the information by magnetizing the information recording surface of the magneto-optical disk, followed by the process of heating the magneto-optical material applied to the surface of the magneto-optical disk to the Curie temperature to lose the magnetism. Done.

In practice, the disc recording medium is formed in a shape protruding in the center of the disc 2 as shown in FIG. An information recording and reproducing section 8 which is formed to record / reproduce information and an edge portion 6 which is formed adjacent to the information recording and reproducing section 8 and is extended. The clamp portion 4 is a part in contact with the clamper (not shown) and serves to fix the disk to rotate smoothly when the disk is rotated. In addition, the information recording and reproducing section 8 is configured to extend from the clamp section 4 and becomes a part capable of recording / reproducing information. On the other hand, the edge portion 6 has a circumferential region having a predetermined width, but many errors occur during recording / reproducing of information and many errors occur during recording / reproducing of information. This area is not used.

On the other hand, in a disc recording medium system, most discs are seated on a turntable (not shown) and rotated, and information recording / reproducing is performed. In this case, the turntable is made of a metal material, and the turntable of the metal material transfers a lot of heat energy generated at high speed to the disk recording medium. In addition, when used in a hot place or a high ambient temperature, the external heat transfer is made to the metal turntable, and the heat energy of the turntable is transferred back to the disc recording medium. However, the heat energy transferred to the turntable causes a temperature difference between the clamp unit 8 and the information recording / reproducing unit 6, thereby causing a buckling phenomenon on the surface of the disc recording medium, which intensifies the vibration of the disc recording medium. Let's go. The change in temperature with the radius of the disc is shown in FIG. 2A.

Referring to the buckling phenomenon in detail, as shown in Figure 2B, the inner peripheral surface and the outer peripheral portion of the disk generates a temperature difference, the tensile force is increased in the inner circumferential portion with a high temperature, the shrinkage force is increased in the outer circumferential portion with a relatively low temperature. At this time, the force due to the tensile force and contraction force acting on one disk at the same time acts on the surface of the disk. If more pressure is applied to the disk, bending occurs on the disk and the disk protrudes up and down. The phenomenon is called buckling phenomenon.

As described above, the disk recording medium according to the related art causes a buckling phenomenon when the heat energy generated by the ambient temperature and the high speed rotation is transmitted to the disk, thereby intensifying the vibration of the disk recording medium. As a result, the rotational speed of the high density disk is a major obstacle to high speed due to the buckling effect.

Accordingly, an object of the present invention is to provide a disk recording medium which minimizes vibration by preventing buckling.

1 is a perspective view of a disc recording medium according to the prior art.

Fig. 2A shows the change in temperature on the disk.

2B shows the strain of a disk over temperature.

3A is a perspective view of a disc recording medium according to the present invention.

Fig. 3B is a sectional view of a disc recording medium mounted on a turntable.

<Description of Symbols for Main Parts of Drawings>

2,12 disc 4,14 clamp part

6,16: information record 18: heat insulation

20: turntable

In order to achieve the above object, the disc recording medium of the present invention is formed in a shape protruding in the center of the disc and includes a clamp portion incorporating heat insulating means.

Other objects and features of the present invention other than the above object will become apparent from the description of the embodiments with reference to the accompanying drawings.

Referring to Figures 3A to 3B will be described a preferred embodiment of the present invention.

Referring to FIG. 3A, the clamp portion 14 is formed to protrude in the center of the disk 12 and has a heat insulating portion 18 therein, and is formed to extend adjacent to the clamp portion 14. And an information recording and reproducing section 18 for recording and reproducing the information, and an edge portion 16 formed in an extended form adjacent to the information recording and reproducing section 18. Since the functions and operation states of the information recording and reproducing section 18 and the rim section 18 are the same as in FIG. 1, detailed description thereof will be omitted. On the other hand, when the heat insulating portion 18 embedded in the clamp portion 14 will be described in detail, the heat insulating portion 18 is made of a material having a low coefficient of thermal expansion such as asbestos, ceramic, etc. It performs a function of interrupting heat transfer between the information recording and reproducing sections 16.

As shown in FIG. 3B, even if the heat energy of the turntable 20 transmitted by the high speed rotation or the external temperature is transmitted to the clamp unit 14 of the disk, it is possible to prevent the information recording and reproducing unit 16 from being transmitted. . This prevents buckling of the disk and minimizes vibration.

As described above, the disc recording medium of the present invention has an advantage of minimizing vibration by preventing buckling by embedding a heat insulating part in a clamp portion of the disc.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (5)

In a disc recording medium comprising: an information recording and reproducing unit for recording and reproducing information; and an edge portion extended and adjacent to the information recording and reproducing unit, And a clamp portion formed to protrude in the center of the disk to include a heat insulating means. The method of claim 1, The disk cartridge, characterized in that the insulating means is formed in an annular band shape inside the clamp portion. The method of claim 1, And a material having a low coefficient of thermal expansion as a material of the heat insulation means. The method of claim 1, Disc recording medium, characterized in that asbestos as a material of the insulating means. The method of claim 1, And a ceramic as a material of said heat insulating means.