JPH01317291A - Optical disk cartridge - Google Patents

Abstract

PURPOSE:To avoid direct interference between a case and an optical disk and at the same time to absorb vibrations by adding an elastic member to either one of two approximate counter surfaces between the disk and the case. CONSTITUTION:An opening part 8 is formed at the center of a case 1 to open a hub 7 and an annular rib 9 is protruded toward an optical disk 2 along the fringe of the part 8. An elastic member 10 having a U-shaped section is fixed to the rib 9. Thus the member 10 functions to prevent the direct interference between the case 1 and the disk 2 and also to absorb the vibrations produced by the collision to the disk 2 by its own elasticity.

Description

TECHNICAL FIELD The present invention relates to an optical disc cartridge for optical information discs such as optical discs, magneto-optical discs, laser discs, and CDs.

2. Description of the Related Art Conventionally, there has been an optical disc cartridge in which, for example, an optical disc is rotatably housed in a flat case. The reason why this cartridge system is used is to protect the optical disc from dust and the like. That is, optical disks have an advantage over conventional magnetic disks in that even if some dust or the like exists on the substrate surface, recording/reproducing operations are not affected. However, even though it is an optical disc, if it is heavily soiled with dust, fingerprints, etc., it is natural that recording and reproducing operations will be hindered. In other words, if the optical disc is exposed, the reliability of data recording and reproducing operations decreases. For this reason, in order to protect the optical disc from dust, dirt, etc., it has been proposed to adopt a cartridge system in which the optical disc is housed in a case. In addition, some cases that store optical discs have
A shutter is provided so that a portion of the optical disc is exposed to an optical pickup during recording and reproducing operations, and a circular opening is formed in the center of the case for connecting the optical disc to the spindle motor shaft.

Problems to be Solved by the Invention Vibrations during the rotation of the optical disc or during transportation may cause the optical disc to come into contact with the case, damaging the surface of the optical disc. As a result, abrasions are generated due to the damage, staining the surface of the optical disc, and may prevent normal recording and reproducing operations.

Means for Solving the Problems In an optical disc cartridge in which an optical disc having a centering member at the center is housed in a case, an elastic member is provided on at least one of the closely facing surfaces of the optical disc and the case. .

The acting elastic part prevents direct interference between the case and the optical disc and absorbs vibrations.Furthermore, since the elastic member deforms due to its own elasticity even when it comes into contact with the case or the optical disc, the elastic member itself and the other member There are no scratches on the surface, and the generation of shavings is prevented.

Embodiment A first embodiment of the present invention will be described based on the drawings. 1 is a flat case, and an optical disk 2 is rotatably housed in this case 1. This optical disc 2 is an air sandwich type in which a space 6 is formed inside by bonding the inner and outer edges of transparent substrates 3 and 4 made of acrylic resin or the like with an annular spacer 5 in between. A hub 7 connected to the shaft of a spindle motor is fixed at the center. This hub 7 has the function of a centering member for the shaft of the spindle motor, but may be formed of a magnetic material. In addition, on the opposite surface of the substrate 3゜4,
A recording layer is formed in which some kind of optical change is caused by irradiation with a laser beam, and the change records optical information.

This recording layer is formed of, for example, an organic dye such as a polymethine dye, or a known material such as a metal, a metalloid, or a metal compound.

At the center of the case 1 is an opening 8 that opens the hub 7.
An annular rib 9 protruding toward the optical disk 2 is formed at the periphery of the opening 8, and an elastic member 10 having a U-shaped cross section is fixed to the rib 9.

In this embodiment, the elastic member 10 is made of silicone rubber, which has excellent elasticity and lubricity properties. The method of fixing the elastic member 1o to the case 1 includes a method of elastic fitting, a method of fixing with an adhesive or an adhesive tape, and the like.

In such a configuration, the elastic member 10 prevents direct interference between the case and the optical disc 2, and absorbs vibrations caused by collision with the optical disc 2 by its own elasticity. Furthermore, the elastic member 10 deforms due to its own elasticity even when the optical disc 2 comes in contact with it while rotating, and has lubricating properties. Generation of powder is prevented. Therefore, shavings will not adhere to the optical disc 2.

Incidentally, when such an optical disc cartridge was used as a sample and vibration was applied at an acceleration of IG and a frequency of 10 Hz in the vertical and horizontal directions for 1 hour each, no change was observed on the surface of the optical disc 2.

When a similar vibration test was conducted on an optical disc cartridge not equipped with the elastic body 10, the surface of the optical disc 2 was scratched and shavings were generated.

Although the optical disc 1 has an air sandwich structure, it may also have a tightly bonded sandwich structure formed by closely bonding the discs together. Although acrylic resin was used for the substrates 3 and 4, plastics such as polyester, acrylic, polyamide, polyolefin, phenol resin, epoxy resin, polyimide,
Glass, ceramics, etc. can be used. The material for the case 2 is preferably a thermoplastic resin because it is molded by injection molding.

Next, a second embodiment of the present invention will be described based on FIG. 2. The same parts as in the previous embodiment are designated by the same reference numerals, and the description thereof will be omitted. In this embodiment, CH2CHCOO (CH2CH20) is placed on the portion of the optical disc 2 facing the rib 9.

A photocurable adhesive mainly composed of an acrylate resin represented by the formula C0CHCH2 is applied and cured to form an annular elastic member 11 with a thickness of 0.05 mm.

Therefore, the elastic member 11 prevents direct interference between the case 1 and the optical disc 2, and absorbs vibrations caused by collision with the rib 9 of the case 1 by its own elasticity. moreover,
Since the elastic member 11 does not rotate and deforms due to its own elasticity even if it contacts the rib 2, the elastic member 11 itself and the rib 9
This prevents the generation of shavings due to interference. Therefore, shavings will not adhere to the optical disc 2. In addition, the results of a vibration test similar to the above example,
No changes were observed on the surfaces of case 1 and optical disc 2. Note that the elastic member may be formed using a thermosetting adhesive instead of a photocuring adhesive.

Effects of the Invention Since the present invention is configured as described above, the elastic member can prevent direct interference between the case and the optical disc and absorb vibrations.Furthermore, the elastic member can prevent itself from coming into contact with the case or the optical disc. Because the elastic member deforms due to its elasticity, the elastic member itself and the other member will not be damaged.
This prevents the optical disc from becoming contaminated with shavings caused by damage, and therefore has the effect of improving the reliability of recording or reproducing operations.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a first embodiment of the invention, and FIG. 2 is a sectional view showing a second embodiment of the invention. ■... Case, 2 - Optical disc, 7... Centering member, 10, 11... Elastic member

Claims (1)

[Claims] An optical disc cartridge comprising an optical disc having a centering member in the center and housed in a case, characterized in that an elastic member is provided on at least one of closely facing surfaces of the optical disc and the case.