JPH03113785A - Disk-shaped recording medium - Google Patents

Abstract

PURPOSE:To simplify and miniaturize a clamping device by providing a permanent magnet for clamping in the disk-shaped recording medium itself. CONSTITUTION:The permanent magnet for clamping the disk-shaped recording medium 20 by magnetic attraction to a turn table is provided on the medium 20 itself near the center hole 20-a of the medium 20. The disk-shaped recording medium clamping device of a magneto-optical information recording/reproducing device is decreased in the number of parts and is extremely simplified and miniaturized according to this constitution.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention mainly relates to the structure of any disc recording medium, such as an optical disc or a continuous disc.

(Prior Art) When a disk-shaped recording medium is held on a turntable in an optical, magnetic, or magneto-optical information recording/reproducing device, a clamp device is provided on the device side.
The center hole of the disk-shaped recording medium is guided to the taper cone placed at the center of the turntable, and the disk-shaped recording medium is pressed and held against the turntable by magnetic attraction by a permanent magnet provided on the turntable side.

As a specific example of this configuration, the one shown in FIG. 5 is known, for example. Here, a spindle motor unit 3 is employed for driving the turntable. The motor unit 3 is constructed by attaching a turntable 11 to a spindle 7 protruding from a motor drive section 12.The spindle 7 is located at the center of the turntable 11, and a taper cone 9 is fitted into the spindle 7 so as to be slidable in the axial direction. It is supported by spring 10. Further, a yoke 8 is provided at the tip of the spindle 7, and a pin insertion hole 13 is protruded from the center thereof. On the other hand, the clamp unit 2#-i has a clamp bin 4 attached to a clamper 6 equipped with a permanent magnet 5 facing the yoke 8.
can be removably inserted into the bottle insertion hole 13, and
It is configured so that the attraction force of the permanent magnet 5 is exerted on the yoke 8.

Then, the center hole 1& of the disk-shaped recording medium 1 is guided to the Chino cone 9, the disk-shaped recording medium 1 is placed on the turntable 11, and the clamp bottle 4 is inserted into the pin insertion hole 13 and clamped by magnetic force. When /46 is pressed against the turntable 11 side, the disk-shaped recording medium 1 is clamped and fixed between the turntable 11 and the clamper 6.

(Problem to be solved by the invention M) However, in the conventional example described above, it is necessary to use a clamp unit 2 with a built-in permanent magnet 5.
t- Must be prepared.

Therefore, the device becomes larger in the thickness direction of the disk-shaped recording medium 1, and the number of parts increases, resulting in higher costs. This is an unfortunate situation, as it goes against the demands for smaller devices and lower costs, and operational reliability is also lowered due to the complicated structure.

(Objective of the Invention) The present invention has been made based on the above circumstances, and by simply slightly improving the structure of the disk-shaped recording medium, the clamping device on the device side can be greatly simplified and miniaturized, and the number of parts can be reduced. The object of the present invention is to provide a disk-shaped recording medium that is devised so as to reduce the amount of energy used, thereby reducing costs and improving reliability.

(Means for Solving the Problems) Therefore, in the present invention, the Q/4 in the clamp device is
In a disk-shaped recording medium that is held on a turntable by the magnetic attraction effect of a permanent magnet by guiding a center hole in a cone, a permanent magnet or a corresponding ferromagnetic material that provides the magnetic attraction effect t is attached to the center hole of the disk. It is located nearby.

(Function) Therefore, there is no need for a clamp device, and the disk-shaped recording medium is attracted and held to the turntable by its own permanent magnet or a ferromagnetic material corresponding to the permanent magnet of the device. As a result, the structure of the equipment has been greatly simplified and has been converted into a shed. Therefore, the number of parts is reduced, thereby reducing costs, and the simple structure improves reliability.

(Example) Hereinafter, an example of the present invention will be specifically described with reference to FIGS. 1 to 4. FIG. 1 shows a disc-shaped recording medium 20 according to the present invention, in which a central hole 20 m
A donut-shaped permanent magnet 21 is attached around the periphery of the magnet. This permanent magnet 21 has a large number of S poles and N poles arranged alternately in the inner circumferential direction, and has nine multipoles, but it does not necessarily have to be multi-pole. A magnetized one may also be used.

FIG. 2 shows a disk drive section of a magneto-optical recording/reproducing apparatus applied to the disk-shaped recording medium 20. As shown in FIG. Here, a base gray (242>E) is attached to the spindle 28 of the spindle motor 29, and the turntable 22 is held and fixed to this by screws 25. A ferromagnetic material 23 is disposed on the turntable 22 and is collinear with the screw 25, so that it can correspond to the permanent magnet 21 provided on the disk-shaped recording medium 20. Further, a taper cone 26 is arranged at the center of the turntable 22, and is supported by a compression coil spring 27.

In such a configuration, the central hole 2 is provided in the tapered cone 26.
When the disk-shaped recording medium 20 is placed on the turntable 22 in a state in which 0m is fitted, the disk-shaped recording medium 20 is attached to the turntable 2 by the magnetic adsorption action of the permanent magnet 21.
It will be held and fixed on 2.

In this embodiment, when the disk-shaped recording medium 20 is supported by the turntable 22, a slot for receiving the permanent magnet 21 is formed on the turntable 22 side so that the permanent magnet 21 does not interfere with this. There is.

Therefore, if the disc-shaped recording medium 20 of the present invention is used, the structure of the disc clamping device on the corresponding recording/playback device side is simplified, no cran noise is required, and this makes it possible to clamp the disc. There are benefits such as no need for a clan/4' operating means.

In the embodiment shown in FIGS. 3 and 4, a permanent magnet 4 disposed in the center hole 39at of the disk-shaped recording medium 39
The multipolar structure of No. 0 is used as it is as the rotor of the spindle motor 48. For this reason, the spindle 52 is pivotally supported by the motor case 49 via a bearing 50, and is fixed to the pace plate 42, and the motor drive coil 47 drives the disk-shaped recording medium 39, and its center hole 391 is formed into a tapered cone. 45 and placed on the turntable 41 in a closed state, it is attached so that it can face the permanent magnet 40. In addition, in the figure, the reference numeral 46 is the tapered cone 45t--the compression coil sgering that elastically supports the tapered cone 45t, and the reference numeral 44 is the turntable 4 with respect to the pace grade 42! , a screw for attaching the ferromagnetic material 43. In addition, in this example,
A means for supporting the motor case 49 in the thrust direction of the spindle 52t is required.

In such a configuration, a change occurs in the magnetic field between the coil 47 and the permanent magnet 21 in response to the current pulse applied to the coil 47.
The disk-shaped recording medium 39 itself functions as a rotor,
It's okay to be rotated.

The height of the motor unit can be reduced.

(Effects of the Invention) In addition to the details described above, the present invention can greatly simplify the flanging device in the disk drive unit because the disk-shaped recording medium itself is provided with a permanent magnet for magnetic attraction necessary for clamping. , it can be made smaller.

Therefore, cost reduction and reliability improvement are also lost.

Note that even if the permanent magnet is provided on the disk drive side and a ferromagnetic material to prevent slipping is provided on the disk-shaped recording medium, an equivalent magnetic attraction effect can be achieved, and this is also within the technical scope of the present invention. In addition, the height of the motor unit can be further reduced, and the height of the entire device can be reduced.

[Brief explanation of drawings]

Figures 1 (,) and (b) are a side view and a plan view of a recording medium showing an embodiment of the present invention, and Figure 2 is a disk drive on the side of a recording/reproducing device used in correspondence with the above recording medium. FIGS. 3(a) and 3(b) are a side view and a plan view of a recording medium showing another embodiment of the present invention, and FIG. FIG. 5 is a vertical side view showing a disk drive unit on the playback device side, and FIG. 5 is a vertical side view of a conventional example. 20... Disc-shaped recording medium, 20 m = Center hole, 21... Permanent magnet, 22... Turntable, 2
3...Ferromagnetic material, 26...Taper cone%29...
・Spindle motor diagram (b) Figure 3 (b)

Claims (1)

[Claims] In a disk-shaped recording medium that is held on a turntable by the magnetic attraction effect of a permanent magnet by guiding a center hole in a taper cone in a clamping device, the permanent magnet or a corresponding ferromagnetic material that provides the above-mentioned magnetic attraction effect is A disc-shaped recording medium characterized in that the disc is disposed close to a center hole of the disc.