JPH0242673A - Disk mounting device - Google Patents

Abstract

PURPOSE:To thin the thickness of a chucking magnet and, simultaneously, to easily execute a mounting by providing a yoke on the back surface of the chucking magnet. CONSTITUTION:When a recording medium is set on the upper surface of a turntable 2 in matching a spindle 1 to a rotation center, a chucking magnet 3 attracts a member to be attracted by a magnetic force. At such a time, a yoke 4 is provided on the chucking magnet 3 installing surface of the turntable 2, and the yoke 4 is made by using a magnetic substance. In such a way, by providing the yoke 4, the attracting force of the chucking magnet 3 is improved. Thus, at the time of executing a comparison in the same attracting force, the thickness of the chucking magnet 3 can be thinned in comparison to the case where the yoke 4 is not provided, and by providing a line, a groove, a projection, etc., for positioning to the yoke 4, the chucking magnet 3 can be surely and, simultaneously, easily fitted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a disk mounting device for holding a medium such as an optical disk by suction using a chucking magnet.

[Prior Art] Magnetic disks, which have excellent operability and storage stability, have been widely used as external storage media in computer systems. On the other hand, in recent years, as the amount of processing by computers has increased, optical discs having the characteristics of a large storage area -4 and short access time have been attracting attention.

A disk loading device is used to perform recording or reproduction using this type of storage medium. For example, the configuration is such that a drive coil is installed on the chassis side, a spindle is placed in the center of the drive coil, and a magnet as a rotor is installed on a turntable that is rotatably attached to the spindle to form a motor. A magnetic disk is attracted and held on a turntable by an attraction mechanism using an attraction member such as a magnet. Note that there is also a configuration in which the drive coil is installed on the spindle side and the magnet is installed on the fixed side.

FIG. 5 is a sectional view showing the main structure of a conventional disk loading device. In Fig. 5, 1 is a spindle rotatably supported by a chassis etc. through a bearing, 2 is a dish-shaped turntable fixed to the upper part of the spindle l, and 3 is a concentric circle on the upper surface of the turntable 2. This is a chucking magnet that is arranged to attract and hold a recording medium placed on the turntable 2. Note that an attractable member made of magnetic metal or the like is provided at a portion of the recording medium (not shown) that faces the chucking magnet 3.

In the above configuration, it is written on the top surface of the turntable 2! 2
When the medium is set with the spindle l aligned with the center of rotation, the chucking magnet 3 attracts the member to be attracted by magnetic force. This puts the recording medium in the same state as when it is pressed onto the turntable 2, and the turntable 2
Even when the recording medium rotates, the recording medium does not shift or fall off, and is stably held.

[Problem to be solved by the invention] However, in the conventional disk mounting device as shown in Fig. 5, in order to reliably attract and hold the recording medium, the magnet must be thick enough to generate sufficient magnetic force. Is it necessary?
The disk mounting surface becomes higher and the thickness of the motor becomes larger, which becomes an obstacle to miniaturization and weight reduction. Furthermore, as the magnet becomes thicker, the leakage magnetic flux also increases, so countermeasures are required, which creates constraints on design and implementation. moreover,
When attaching the chucking magnet, it is necessary to position and fix it uniformly so as not to cause uneven rotation, but this is actually difficult.

The present invention has been made to solve these problems, and an object of the present invention is to provide a disk mounting device that reduces the thickness of a chucking magnet and facilitates mounting without impairing the attraction force.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a yoke on the surface of a chucking magnet.

Further, at least the portion of the turntable where the chucking magnet is attached can be processed from a magnetic material to form a yoke.

[Operation] According to the configuration of the first invention, the yoke plows to increase permeance. Therefore, if the same chucking magnet is used, the chucking force can be increased compared to when no yoke is used, and if the same chucking force is to be obtained, the chucking magnet can be made thinner by providing a yoke. Ru.

Further, in the configuration of the second invention, by using a magnetic material for the turntable, it becomes possible to serve both the turntable and the yoke. Therefore, the yoke can be formed without increasing the number of parts.

[Embodiment] FIG. 1 is a sectional view as an embodiment of the present invention. In FIG. 1, the same reference numerals are used for the same parts as in FIG. 5, so redundant explanations will be omitted.

As shown in FIG. 1, the present embodiment is characterized in that a yoke 4 is provided on the surface of the turntable 2 on which the chucking magnet 3 is installed. Yoke 4 is made using a magnetic material.

By providing the yoke 4 in this manner, the attraction force of the chucking magnet 3 is improved. Therefore, when compared at the same attraction force, the thickness of the chucking magnet 3 can be made thinner than when the yoke 4 is not provided. Furthermore, when surface magnetization is applied, a closed magnetic path is formed, so there is no need to consider leakage magnetic flux. Also, when installing the chucking magnet 3, make sure that the yoke 4
By providing positioning lines, grooves, protrusions, etc., the chucking magnet 3 can be attached reliably and easily.

FIG. 2 is a sectional view showing a state in which the recording medium 5 is mounted on the disc mounting device shown in FIG.

When the hole provided at the center of rotation of the recording medium 5 is applied to the upper end of the spindle 1 and the recording medium 5 is lowered,
The yoke 4 attracts the opposing surface of the recording medium 5 by magnetic force.

This suction force brings the recording medium 5 into pressure contact with the turntable 2, and even if centrifugal force due to the rotation of the spindle 1 is applied, the recording medium 5 is stably held without causing positional deviation.

53 is a sectional view showing another embodiment of the present invention.

In this embodiment, the turntable can also be used as a yoke, whereas the yoke was provided separately in the previous embodiment. For this purpose, the turntable 6 is made of a magnetic material as a turntable, and the chucking magnet 3 is disposed on the turntable 6. Since the turntable 6 is made of magnetic material, it functions as a yoke and increases the attraction force as in the previous embodiment.

Therefore, in this embodiment as well, the thickness of the chucking magnet 3 can be made thinner in order to maintain the same attraction force.

FIG. 4 is a sectional view showing a modification of the embodiment shown in FIG.
Instead of processing the entire turntable 6 using a magnetic material, it is configured such that the medium mounting portions 7 are individually mounted on the periphery. The medium mounting part 7 is made of a rust-resistant material, and is connected to the peripheral edge of the disc-shaped turntable 6' by caulking.
will be integrated into.

In the configuration shown in FIG. 3, when cutting is performed using hide or the like to correct surface runout on the medium mounting surface, rust is likely to occur because the magnetic material contains iron. but,
By using the medium mounting part 7, surface runout can be corrected by cutting the medium mounting part 7, and rust will not occur.

[Effects of the Invention] Since the present invention is configured as described above, the following effects can be obtained.

In the configuration of the first invention, since the yoke is provided on the back surface of the chucking magnet, the chucking magnet can be made thinner, and the device can be made smaller, lighter, and cheaper. Furthermore, when surface magnetization is applied, a closed magnetic path is formed, so there is no need to consider leakage magnetic flux.

Furthermore, the chucking magnet can be easily attached to the turntable, improving assembly efficiency and reliability.

In the configuration of the second invention, at least the part of the turntable where the chucking magnet is attached is processed with a magnetic material, so that the chucking magnet can be made thinner without providing a separate yoke. This also makes it possible to reduce the number of parts.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of one embodiment of the invention. FIG. 2 is a cross-sectional view showing a state in which a recording medium is loaded into the disk loading device shown in FIG. 1, FIG. 3 is a cross-sectional view showing another embodiment of the present invention, and FIG. FIG. 5 is a cross-sectional view showing a modification of the example, and FIG. 5 is a cross-sectional view showing the main structure of a conventional disk loading device. In the figure. 1. Spindle 2.6, 6°: Turntable 3: Chucking magnet 4 = Yoke 7: Media mounting department agent Patent attorney 1) Haru Kitatake Figure 1 Figure 2 Figure 3

Claims (2)

[Claims] (1) A disc loading device that attracts and holds a recording medium placed on a turntable by the attraction force of a chucking magnet provided on the turntable side, characterized in that a yoke is provided on the back surface of the chucking magnet. Disc loading device. (2) The disk loading device according to claim 1, wherein at least a portion of the turntable where the chucking magnet is attached is processed to form the yoke using a magnetic material.