JPH0256752B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Technical Field of the Invention> The present invention relates to a magnetic disk device, and more particularly to arm return means for always returning an arm having a magnetic head at its tip to a fixed position when the magnetic disk is not driven. It is.

<Technical background> The magnetic head of a magnetic disk device comes into contact with the surface of the magnetic disk and stops when the magnetic disk is not being driven.This contact position is placed on the magnetic disk so that the stored information is not destroyed when the magnetic head starts or stops. Floating area other than the writing area (CSS area:
Contact Start Stop Zone). Such floating areas are usually provided on the outermost or innermost tracks of the magnetic disk. The magnetic head is provided at the tip of the arm, and when the magnetic disk is not driven, the arm is biased by arm return means toward the outermost or innermost floating area of the magnetic disk, and the magnetic head is positioned within this floating area.

<Prior art and problems> Conventional means for returning a rotary arm, for example, include attaching a coil spring to the arm rotation shaft to bias the arm in a certain direction, or arranging a magnetic disk vertically to reduce the arm's own weight. A method has been used in which the arm returns to a fixed position when the power is turned off. However, in the method using a coil spring, dust of micron size is generated due to friction at the contact between the coil spring and the arm rotating shaft or device fixing point, which adheres to the magnetic disk surface and causes head crash, and the life of the coil is shortened. This method cannot be applied to magnetic disk devices which are limited and frequently used, and the method of self-returning by its own weight has limited versatility because the position of the floating area on the magnetic disk surface is limited.

<Objective of the Invention> The present invention has been made in view of the drawbacks of the above-mentioned prior art, and provides a magnetic head arm that can be used semi-permanently without generating dust and that provides stable seek operation of the magnetic head. An object of the present invention is to provide a magnetic disk device equipped with a return means.

<Structure of the Invention> In order to achieve this object, in the present invention, one component of a spring constituted by a combination of a magnet and a magnetic material or a combination of magnets is fixed to the rotating shaft of an arm having a magnetic head at the tip. The other component of the spring is fixed on a stationary member surrounding the arm rotation shaft of the magnetic disk device so as to face the other component fixed to the arm rotation shaft. .

<Embodiments of the Invention> FIG. 1 is a front view of a magnetic disk device according to the present invention. A floating area 2 is provided on the outermost track of the magnetic disk 1. A magnetic head 4 is provided at the tip of the arm 3, and the magnetic head 4 rotates around the rotation axis 5 of the arm 3 to rotate the magnetic disk 1.
When the seek operation is completed, the arm returns to the floating area 2 by the arm return means according to the present invention shown in FIG. An actuator consisting of an electromagnetic coil 6 and a magnetic circuit section 17 is provided at the rear end of the arm 3 to perform a seek operation of the arm.
The rotating shaft 5 of the arm 3 is provided with a magnetic material member 9 having a cross-sectional shape shown in FIG. This magnetic material member 9 is placed in a stationary sleeve 7 fixed to the device main body (not shown) at a position where it does not come into contact between permanent magnets 8a and 8b fixed facing each other. The permanent magnets 8a, 8b and the magnetic material member 9 constitute a non-contact magnetic attraction type spring. is energized by Therefore, after the seek operation of the arm 3 is completed by another seek drive source of the arm 3, the magnetic head 4 is moved to the floating area 2 by this non-contact magnetic attraction spring.
The arm 3 can be returned to a fixed position so as to be located inside.

Another embodiment of the invention is shown in FIGS. 3 and 4. The arm 3 is installed in a sealed housing 11 together with an arm support 10 . A magnetic material member 9 constituting the non-contact magnetic attraction spring described above is provided at the top of the rotating shaft 5 of the arm 3. A permanent magnet 16, which together with the magnetic material member 9 constitutes a non-contact magnetic attraction spring, is fixed to the flange member 12 and placed outside the sealing casing 11 via a cover 13 made of a non-magnetic material. The cover 13 is hermetically fixed to the sealing casing 11 so as to keep the inside airtight. A packing 14 is provided on the lower surface of the flange member 12. The flange member 12 has a long hole 18
It is fixed to the sealing casing 11 with screws 15 through it. The initial setting position of the biasing force of the non-contact magnetic attraction spring against the arm 3 can be set to the optimum position by loosening the screw 15 from the outside of the sealing casing 11, rotating the flange member 12, and adjusting the position of the permanent magnet 16. is set to

The above explanation has been given using a rotating carriage as an example, but non-contact magnetic attraction springs can also be applied to linear carriages using VCM, and non-contact magnetic attraction springs can also be used between permanent magnets. It can also be configured by a combination of.

<Effects of the Invention> As explained above, in the magnetic disk device according to the present invention, a non-contact magnetic attraction spring is used as the arm return means for returning the magnetic head to the floating area. No dust is generated due to the friction of the contact parts, and it can be used semi-permanently, achieving stable and reliable seek operations. In addition, by providing one component of the non-contact magnetic attraction spring outside the sealed casing of the magnetic disk device, the use range of the biasing force characteristics of the spring can be set at the optimum position while maintaining the internal seal of the device. can.

[Brief explanation of drawings]

FIG. 1 is a front view of a magnetic disk device according to the present invention, FIG. 2 is a configuration diagram of an example of a non-contact magnetic attraction spring according to the present invention, and FIGS. FIG. 3 is a top view and a cross-sectional view of an example. DESCRIPTION OF SYMBOLS 1... Magnetic disk, 2... Floating area, 3... Arm, 4... Magnetic head, 8a, 8b, 16... Permanent magnet, 9... Magnetic material member.

Claims (1)

[Scope of Claims] 1. One component of a spring constituted by a combination of a magnet and a magnetic material or a combination of magnets is fixed to the rotating shaft of an arm having a magnetic head at the tip, and the other component of the spring is A magnetic disk device characterized in that the component is fixed on a stationary member surrounding the arm rotation shaft of the magnetic disk device so as to face one component fixed to the rotation shaft of the arm. 2. In the magnetic disk device according to claim 1, the spring provided on the rotating shaft portion uses a portion where the rotational torque is averaged in the data area,
A magnetic disk device characterized in that a portion where the rotational torque is close to zero is used as a region where an arm returns.