JPS6292197A - Magnetic disc device - Google Patents

Abstract

PURPOSE:To prevent the resonance of a magnetic head in the access direction by means of a head disc assembly and vibrationproof rubber legs by fitting a stopper to the head disc assembly and arranging the said stopper on a support frame with a gap or contact. CONSTITUTION:It is possible to prevent the vibration of a magnetic head 24 just after the end of accessing by suppressing the vibration of the head disc assembly 21 in the head access direction by means of two stopper brackets 31. When the displacement of the head disc assembly 21 is small, the restoration force is due to vibrationproof legs 22 only and when the displacement is larger and the stopper brackets 31 contact the frame 23, the spring constant is larger. Nonlinearity is given to the reading force to prevent the resonance due to the head disc assembly 21 and the vibrationproof rubber legs 22 thereby preventing the vibration of the magnetic head 24 just after the end of accessing.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a magnetic disk drive, and more particularly to a vibration prevention structure for a load disk assembly.

[Background of the invention]

Figure 5 shows an example of a magnetic disk drive according to the prior art.

The head-disk assembly 1 is attached to a frame 3 via a vibration-proof rubber 2, absorbs external impact transmitted through the frame 5 during transportation, and is enclosed in the head-disk assembly 1. Damage to the magnetic head 41 and magnetic disk 5? To prevent. Further, the structure is such that the magnetic head 4 can normally access the magnetic head 4 by insulating and absorbing the peristaltic force applied to the frame 3 from the outside during operation. The access mechanism for the magnetic head 4 includes a carriage 6 that supports the magnetic head 4 and moves QTfD, and a carriage 6 that rotates around a fixed axis (b).
It consists of a voice coil motor 7 for rotationally driving and positioning the magnetic hect 4 at an arbitrary radial position on the magnetic disk 5. Then, when an access command for the magnetic head 4 is issued,
The carriage 6 is rotated by the voice coil motor 7, and the magnetic head 4 attached to the carriage 6 starts moving in the radial direction of the disk. At this time, the magnet 17 of the voice coil motor 7 fixed to the base plate 8 of the head/disk support body 10 receives the reaction force of the carriage movement. On the other hand, since the head/disk assembly 1 forms a spring/mass system with the anti-vibration rubber legs 2, it has a specific number of natural vibrations of 427. The entire disk assembly f41 will undergo S motion with its own number of motions. This photographing of the entire disk assembly 1 of the head acts as a disturbance on the magnetic head positioning servo system, causing vibration of the magnetic head 4 immediately after the positioning operation is completed, resulting in a decrease in positioning accuracy.

Figure 6 shows positioning servo system device signals obtained from a pair of magnetic heads and a magnetic disk (servo head and servo disk). Immediately after the magnetic head finishes moving to the target position, vibrations of the entire head/disk assembly become vibrations of the magnetic head, reducing positioning accuracy.

The reason why this magnetic head image becomes remarkable is that the vibration of the head-disk assembly is at its maximum, that is, the access period of the magnetic head matches the resonance frequency of the head-disk assembly and the root-proofing rubber. It's time.

As a known example close to the present invention, Japanese Patent Application Laid-Open No. 57-1058
There is a method for supporting a head-disk assembly shown in No. 72.

[Purpose of % Ming]

The purpose of non-invention is to eliminate the problems of the prior art.

The purpose is to prevent the entire head-disk assembly from being photographed during the access operation of the magnetic head, and to prevent the positioning accuracy of the magnetic head from decreasing immediately after the access operation is completed.

[Summary of the invention]

In order to achieve this object, the magnetic disk drive according to the present invention has a stopper attached to the head disk assembly, and this stopper is placed in contact with the support frame or with a gap between the head disk assembly and the head disk assembly. It is characterized by suppressing resonance caused by the anti-vibration rubber and preventing vibration of the magnetic head caused by vibration of the entire head-disk assembly immediately after the end of an access operation, thereby improving positioning accuracy.

[Embodiments of the invention]

Embodiments of the present invention will be described below using Figures 1 and 2.

Reference numeral 21 denotes a head/disk assembly, which forms a completely sealed structure with a pace plate 28 and a cover, and includes a magnetic head 24 and a magnetic disk 25 inside. L-shaped metal fittings 29 are attached to the pace plate 28 at two places on the left and right, and four vibration-proof rubber legs 22 are attached to the L-shaped metal fittings 29. On the other hand, brackets 20 are attached to the frame 26 at two positions on the left and right, and the brackets 20 support the four vibration-proof rubber legs 22 of the front d-pins on the frame 23. Two left and right stopper brackets 51 are attached to the above-mentioned metal fitting 30, and are arranged in contact with or with a slight gap from the bracket 2o fixed to the frame 23.

During normal transportation, shocks are applied to the frame 23 from the outside, but the shock-absorbing effect of the rubber feet 22 prevents the impact from being transmitted to the head/disk assembly 21, and the magnetic head 24. Damage to the magnetic disk 25 is prevented. Also, the vibration that is applied to the 7-arm 23 from the outside during operation! IEI7? :
The magnetic head 2 is insulated and absorbed by the vibration isolating rubber legs 22.
4 is configured so that normal access operations of 4 can be performed.

Figures 1 and 2 are internal perspective views of Figure 1. When an access command for the magnetic head 24 is issued, the carriage 26 is rotationally driven by the voice coil Tanabata 27, and the magnetic head 24 is rotated by the voice coil Tanabata 27.
movement begins. The reaction force of the movement of the magnetic head 24 and carriage 26 is received by the magnet of the voice coil motor 27 fixed to the pace plate 28, and as a result, the entire head/disk assembly 21 is moved by the anti-vibration rubber legs 22. # It acts to cause vibration at the natural vibration frequency. This vibration of the head-disk assembly 21 remains as a vibration of the magnetic head 24 immediately after the access operation is completed, causing a decrease in positioning accuracy. (, 4'F2 direction in Figure B), this becomes noticeable. The S movement of the head/disk assembly 21 in the head access direction is controlled by the two stopper brackets 3.
1 makes it possible to prevent vibration of the magnetic head 24 immediately after the access operation is completed. Figure 3 shows the relationship between the restoring force and the horizontal displacement of the head/disk assembly 21 (in the direction of B in Figure 2). head·
While the displacement of the disc assembly 21 is minute, the anti-vibration rubber legs 2
However, as the displacement becomes thicker and the stopper bracket 31 comes into contact with the frame 23, the spring constant becomes thicker. By giving nonlinearity to this restoring force, the disk assembly of the head The solid body 21 and the anti-vibration rubber legs 22 prevent vibration of the magnetic head 24 immediately after the access operation is completed.

During normal transportation or handling, shocks and vibrations applied through the frame 25 are mainly in the vertical direction, and the stopper bracket 61 has no effect on the vertical direction, so the absorption effect of the anti-vibration rubber legs 22 is reduced. It won't hurt.

FIG.
[Shio 1] is designed to prevent wear due to contact with the rubber legs 22 and to prevent friction in the vertical direction so as not to impair the vertical root sucking effect of the root preventing rubber legs 22.

〔Effect of the invention〕

As described above (according to the present invention), by attaching a stopper to the head/disk assembly and disposing the stopper in contact with the support frame or with a gap between them, the magnetic force generated by the head/disk assembly and the anti-vibration rubber legs is improved. It is possible to improve positioning accuracy by preventing resonance in the access direction of the head and preventing vibration of the magnetic head caused by vibration of the entire head-disk assembly immediately after the end of the head access operation.

[Brief explanation of drawings]

Figure 1 is a perspective view of a magnetic disk device according to the present invention.
Figure 2 is a perspective view of the inside of Figure 1 (viewed from the entrance direction), 2 years old and 3 years old.
Figure 1 is a diagram illustrating the relationship between the position of the head-disk assembly displaced from its balanced position and its restoring force.
Figure 5 is a perspective view of a magnetic disk device according to the prior art, and Figure 6 is a diagram showing positioning servo signals during an access operation. 21... Head disk assembly, 22... Root-proofing rubber legs, 23... Frame, 24... dfi head,
25... aflfi disk, 26... carriage, 27... voice coil motor, 2nd... base plate, 29... L-shaped fitting, 20... bracket,
31...Stopper bracket, 32...Low friction material plate.

Claims (1)

[Claims] 1. A head including a magnetic head and a magnetic disk.
A disc assembly, a vibration-isolating rubber leg attached to the head-disk assembly for insulating vibration from the support portion, and a frame supporting the head-disk assembly via the vibration-isolating rubber leg. 1. A magnetic disk drive comprising: a stopper attached to the head/disk assembly and disposed in contact with the frame or with a gap therebetween. 2. A magnetic disk drive according to claim 1, characterized in that a low-friction material is attached to the contact surfaces of the stopper and the frame.