JPH06139692A - Disk driving device - Google Patents

Abstract

PURPOSE:To make the device so that a strong attracting force is exerted at the starting up time while not exerting the attracting force at the time of insertion/ejection and the attracting force is changed to the weak state during the rotation to allow the rapid starting up without slip at the time of rotation. CONSTITUTION:A driving part 4 of a spindle hub A is fixed on the spindle 2, and an electromagnetic part 3 is formed of an external yoke 3b and a boss- stated yoke 3c, and a coil 5 is provided on the outer periphery of the yoke 3c. A control circuit 6 is connected to the coil 5, and the driving part 4 is formed by connecting the external yoke 4a and cylindrical yoke 4b, the yoke 4a and cylindrical yoke 4b through nonmagnetic materials 7 such as a resin, casting, etc. In the electromagnetic part 3 and the driving part 4, the yoke 3b and yoke 4a, the yoke 3c and yoke 4b are opposed repectively at a space (t), and on the spindle 2 protruded from the spindle hub A, magnetic materials 9 are placed while fitting a center hole 8a of a media disk 8 on the spindle 2. The magnetic materials 9 are fixed on both sides of the hub of disk 8. Top parts of the inner/outer yokes 4a, 4b of the driving part 4 are exposed to the side of the disk 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk drive device having a spindle hub which attracts and rotates a disk hub.

[0002]

2. Description of the Related Art In the conventional floppy disk which has been widely used as a disk, a pin provided on a spindle hub is fitted into a hole of the disk hub to integrally rotate both hubs. On the other hand, like a magneto-optical disc, recording / contacting can be performed without contact.
There is no mechanical clamp in the disk drive device of the media disk for reproduction, and a permanent magnet 11 is provided in the chucking hub 10 fixed to the spindle 2 of the motor 1 as shown in FIG. The rotation of the spindle was transmitted to the media disk by attracting the media side magnetic material 9 such as an iron plate attached to the media disk. In addition, special fair 3
Similarly, in the −11020 publication, a permanent magnet is fixed to the motor spindle.

When the rotational force is transmitted to the media disc by the attraction force of the permanent magnet as described above, the media disc slips when it is desired to start it up rapidly. At the end of the operation, in order to remove the media disc early,
When a forced brake is applied to the computer, it slips between the chucking hub and the media disc. The magnetic attraction force of the permanent magnet acts at the time of attachment / detachment, and the force for removing the disk must be greater than the attraction force. When the permanent magnet is strengthened to prevent slippage, a stronger force is required due to media ejection.

[0004]

The problems to be solved are that slippage is likely to occur, and media ejection must be performed against the magnetic attraction force. In view of the above-mentioned drawbacks, the object of the present invention is to exert no suction force at the time of attachment / detachment, to exert a strong suction force at the time of start-up, and to change it to a weak suction force during rotation, and rapidly during rotation without slipping. The purpose of the present invention is to propose a disk drive device that can be started up and lightly attached and detached.

[0005]

SUMMARY OF THE INVENTION The present invention is a disk drive device having a spindle hub that attracts and rotates a disk hub, wherein the spindle hub is composed of a fixed electromagnetic part and a drive part integrated with the spindle. The gist is that the inner and outer yokes of the electromagnetic portion and the drive portion face each other, and the tops of the inner and outer yokes of the drive portion are exposed to the disk side.

[0006]

When the media disk 8 is placed on the drive section 4 of the spindle hub A and a strong attracting current is applied to the coil 5 of the electromagnetic section 3 from the control circuit 6, the yoke is looped as shown in the figure. The magnetic path a is formed in the media, and the media disk 8 is surely adsorbed. When the motor 1 is energized, the spindle 2 is rotated and the drive unit 4 of the spindle hub A and the media disk 8 are rotated. During this rotation, a strong adsorption current may be applied to the coil 5, or a slightly weaker adsorption current may be applied. When the media disk 8 is removed, the coil 5 is lightly removed with no attraction force without energizing the coil 5.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to one embodiment shown in the drawings.
FIG. 1 is a sectional side view of a main part of a disk drive device.

In the disk drive device, a spindle 2 is projected from a motor 1. The electromagnetic portion 3 of the spindle hub A is fixed to the upper portion of the motor 1 and the spindle 2 is inserted into the center hole 3a. The drive unit 4 of the spindle hub A is fixed to the spindle 2. The electromagnetic part 3 is an outer yoke
3b and a boss-shaped yoke 3c, and a coil 5 is provided on the outer circumference of the yoke 3c. A control circuit 6 is connected to the coil 5. The drive unit 4 includes an outer yoke 4a, a cylindrical yoke 4b, and
The yoke 4a and the cylindrical yoke 4b are connected and formed by a non-magnetic material 7 such as resin or casting. The electromagnetic portion 3 and the driving portion 4 are opposed to each other with a slight space t between the yoke 3b and the yoke 4a, and the yoke 3c and the yoke 4b. The spindle 2 protruding from the upper part of the spindle hub A has a center hole 8a of the media disk 8 on the spindle 2.
Are fitted and the magnetic material 9 is placed. Magnetic materials 9 are fixed to both sides of the hub of the disk 8. The tops of the inner and outer yokes 4a and 4b of the drive unit 4 are exposed to the disk 8 side.

The operation of the disk drive device is such that when the media disk 8 is placed on the drive part 4 of the spindle hub A and a strong attracting current is applied from the control circuit 6 to the coil 5 of the electromagnetic part 3, the yoke is operated. A magnetic path a is formed as in the loop of the figure, and the media disk 8 is surely adsorbed. Motor 1
Is energized, the spindle 2 is rotated and the drive unit 4 of the spindle hub A and the media disk 8 are rotated.
During this rotation, a strong adsorption current may be applied to the coil 5, or a slightly weaker adsorption current may be applied. When the media disk 8 is removed, the coil 5 is lightly removed with no attraction force without energizing the coil 5.

When the disk drive is operated as described above, there is a case in which a media lever is operated by a manual lever, but since the power supply is cut off, there is almost no attraction force and the operation force can be reduced. . Furthermore, in order to make the rotation speed of the media disk 8 faster to record / reproduce,
For example, it is also possible to receive a strong signal at the time of rising from the tachogenerator of the motor and synchronize with this to change the current flowing from the control circuit 6 to the coil 5 to adjust the attraction force.

When the disk drive device is constructed as described above, the attracting current controlled by the control circuit 6 is applied to the coil 5 of the electromagnetic section 3 so that the attracting force does not act upon attachment / detachment and is strong at start-up. The suction force is applied, and it can change to a weak suction force during rotation, and it can quickly start up without slipping during rotation and can be lightly attached and detached during attachment and detachment. Furthermore, since the attracting force can be adjusted by changing the current passing through the coil 5 in synchronism with the rising signal of the tachogenerator of the motor, the attracting force can be obtained from a permanent magnet with a constant attracting force. The rise and fall of the media disk 8 can be made more freely.

[0012]

Since the present invention is constructed as described above,
The attraction current is applied to the electromagnetic part so that no attraction force is applied when attaching or detaching, a strong attraction force is applied when starting up, it can change to a weak attraction force during rotation, and there is no slip during rotation. It is possible to provide a disk drive device that has excellent effects such that it can be started up quickly and can be lightly attached and detached at the time of attachment and detachment.

[Brief description of drawings]

FIG. 1 is a cross-sectional side view of essential parts of a disk drive device.

FIG. 2 is a sectional side view of a main part of a conventional disk drive device.

[Explanation of symbols]

 2 Spindle 3 Electromagnetic part 3b, 3c, 4a, 4b Yoke 4 Drive part 8 Media disc A Spindle hub

Claims (1)

[Claims] 1. A disk drive device having a spindle hub which attracts and rotates a disk hub, wherein the spindle hub is composed of a fixed electromagnetic part and a drive part integrated with the spindle, and the electromagnetic part and the drive part are respectively formed. A disk drive device in which the inner and outer yokes face each other and the tops of the inner and outer yokes of the drive unit are exposed to the disk side.