JPS59210577A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To attenuate mechanical vibration quickly and to reduce the positional deviation of track of the magnetic head of an information processing device by bringing a mechanical vibration attenuating member into press contact with the stator of the head driving device of an access mechanism by an elastic member attached to the inside of a cover of specified thickness. CONSTITUTION:A metallic spring 14 such as phosphor bronze is fixed to the inside of a thick cover 13, and a mechanical vibration attenuating member 15 is attached. The mechanical vibration attenuating member 15 is brought into press contact with a stator 9 energizing it by the metallic spring 14. The mechanical vibration attenuating member 15 is simply pressed against the stator and the stator is not joined to the mechanical vibration attenuating member mechanically. By such constitution, energy of vibration is absorbed by attenuating action due to internal friction in the mechanical vibration attenuating member. Further a part of energy of vibration is absorbed by friction on the pressure contact face between the mechanical vibration attenuating member 15 and stator 9. Thus, accurate track positioning of the magnetic head 5 can be maintained always by attenuating mechanical vibration due to reaction force of movement of the head driving device 8 quickly.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a magnetic disk device, and more specifically, to a device that performs random access, and in which a single stroke of a head drive device that occurs when performing high-speed access is suppressed. Accordingly, the present invention relates to a structure that allows high-speed and highly accurate positioning.

(b) Background of the Technology In electronic computer systems, magnetic disk drives are currently a typical file device and are widely used as the basic component of disk heirth systems, from small-scale systems to large-scale systems.

It has particularly excellent high-speed access functions and is heavily used for storing online data.

+c) Prior Art and Problems As is well known, a magnetic disk drive has a rotational drive mechanism that stably rotates the disk at a specified number of rotations, an access mechanism that moves the magnetic head and positions it to a desired track,
Writing/reading information on the disk and vice versa
It is composed of a reading mechanism, a control section that controls traffic between a host device and a magnetic disk device, collates records, and controls storage and reproduction of information, and a magnetic disk that stores information.

The present invention relates to the above access mechanism.

The access mechanism places the magnetic head on the disk surface /i! The system allows the device to float stably while keeping a constant minute distance from the disk surface, and move it to the selected track position at high speed and accuracy.The positioning accuracy is extremely important in order to improve the recording density of the disk. It's important.

The first section is a sectional view conceptually showing a conventional magnetic disk device. A spindle 2, which normally holds a plurality of magnetic disks 1 and rotates them at high speed, is supported by upper and lower ball bearings 4 mounted on a sturdy base plate 3, and is driven by a rotation drive device (not shown).

A cart 7 loaded with a head arm 6 supporting a magnetic head 5 is moved back and forth in the radial direction of the magnetic disk 1 by a head drive device 8 to move the magnetic nod 5 to a desired position from 1 to crank at high speed. The head driving device 8 of this example is a moving coil type linear motor, and is composed of a stator 9 and a movable element 10 as shown. Normally, the track position is selected by linear morph control by reading position information written in advance on one side of the magnetic disk 1 or another fixed magnetic disk using the servo magnetic head 11.

Above trolley 7. Both of the head drive devices 8 have the above-mentioned -\-
Sprays 1 to 3 are provided above.

Also, the gap between the disk 1 and the magnetic throat 5 should be 0.2~
Since the dust is as small as 0.5 μm, even floating dust in the air can be a major hindrance, so it is usually equipped with a dustproof cup.

In such a structure, the nine carts 7 move at high speed, and each time they move, a huge reaction force is generated by the stator 9 against the heath plate 3.
, and generates a mechanical vibration ωj that continues for a certain period of time.

If you stand on the truck 7, this reaction force G reaches 10 to 20 kg. Therefore, each time 1 reaction force is applied, Heisbrae 1 to 3
bending deflection due to mechanical vibration occurs. As a result of this bending deformation of the base plate 3, the plurality of hems 5 loaded on the trolley 7 are naturally tilted slightly and their track positions are shifted, reducing the accuracy of access of the gutter device to the magnetic field. The diameter of recent magnetic disk devices is approximately 20 to 50 μm.

Even a deformation of the base plate 3 of several μm sensitively affects the positioning accuracy of the magnetic head 5.

As for the second countermeasure, there is no choice but to reduce the weight of the bogie 7 as much as possible and to make the Hespray 1-3 stronger, but both of them have their own limits.

As a current countermeasure, as shown in Figure 2, there are two base plates and a stator 9 is mounted on the Hespray) A3.
The spindle 2 and truck 7 are mounted on C (Hespray) B (3b) via the connecting member \a.

The reaction force based on the movement of truck 7 is directly base play) B3b
There are some devices that do not add to this, but they have the disadvantages of 1) a complicated mechanism, an increase in the size of the entire device, and 3 a skyrocketing price.

Some alternative solution to strengthening the base plate 3 has been desired for a long time.

((j) Purpose of the Invention The purpose of the present invention is to provide a machine in which the displacement of the trunk position of the truck 5 is induced by the reaction force of the truck 7 as described above. Since this is caused by physical vibration, we aim to provide a structure that reduces the 1-rank positional deviation of the magnetic head of an information processing device by absorbing the mechanical vibration itself. It is something.

(el) Composition of the Invention The object of the above invention is to provide a magnetic disk drive having a magnetic disk rotation mechanism, a write/read mechanism, an access mechanism, and a control section, in which an elastic material fixed to the inner surface of a cover with a predetermined thickness by pressing the mechanical vibration damping member against the stator of the head drive device of the access mechanism with a member;
This is easily achieved by forming a mechanical vibration damping mechanism that quickly damps mechanical vibrations generated by the movement of the access mechanism.

(f) Embodiments of the invention Examples of the invention will be described below with reference to the drawings. FIG. 3 shows an embodiment of an improved positioning mechanism for a magnetic head of a magnetic disk drive according to the present invention.

In the present invention, a relatively thick cover 13 having mechanical strength is used in place of the dustproof cover 12.

As shown in FIG. 3, a metal spring 14 such as a phosphor bronze plate is fixed inside the thick cover 13, and a mechanical vibration damping material 15 (damper) is attached to the metal spring 14. The mechanical vibration damping material 15 is pressed against the stator 9 by applying force. Since the mechanical vibration in question is a high frequency vibration of several hundreds of rutz, a synthetic resin material is generally effective as the mechanical vibration damping phase 15 for this purpose.

The mechanical vibration damping material 15 may be fixed to the metal spring 14 by adhesive or screwing, or may not be fixed by providing some kind of guide mechanism. For the stator 9 of the head drive device 8, one mechanical vibration damping material 15 is simply replaced with a metal spring 1.
4, the stator 9 and the mechanical vibration damping phase 157 are not mechanically connected.

The mechanical vibration of the head/throat drive unit 8 of a conventional magnetic disk device is close to free vibration because the head plate 3 on which the drive unit is mounted is in the form of a metal (aluminum) cantilever beam. As a result, the position of the magnetic head 5 vibrates back and forth in the radial direction of the magnetic disk 1, making its trunk position inaccurate and unstable. According to the present invention, the conventional dustproof cover 12 for dustproofing is simply strengthened and the cantilever structure of the hair plate 3 is changed to a structure similar to each shell structure.
The vibration energy is absorbed by the damping effect due to internal friction within the member, and a part of the vibration energy is absorbed by the friction at the pressure contact surface between the mechanical vibration damping material 15 and the stator 9.

Vibration can be stopped within a very short time.

In the above-described embodiment, in order to suppress the mechanical vibration of the head drive bag b:8, a structure is adopted in which the metal spring 14 is omitted and the mechanical vibration damping material 15 is directly fixed to both the cover 13 and the stator 9. Although there is also iJ, this structure is inappropriate for the following reasons. That is, the high speed rotation of the magnetic disk 1 (
Air friction associated with 3000-4000 PPM? The heat generated by rotational friction loss between the jS and the ball bearing 4 causes a difference in the temperature of the cover 13 and the heat plate 3, resulting in a difference in thermal expansion. This is because if the mechanical vibration damping material 15 and the stator 9 are stuck together, this difference in thermal expansion will directly affect the position of the magnetic heel 5, so it is necessary to slide the mechanical vibration damping material 15 and the stator 9 together. Therefore, it is clear that a structure in which the stator 9 and the mechanical vibration damping material 15 are fixedly attached and the mechanical vibration damping material 15 and the cover 13 are allowed to slide may be used.

(g+ Effects of the Invention As is clear from the above description, the present invention provides a cover 13 for a magnetic disk drive, a mechanical vibration damping mechanism composed of an elastic member such as a metal spring 14, and a mechanical vibration damping material 15 such as a synthetic resin. By introducing this, there is an effect that the mechanical vibration caused by the reaction force of the movement of the head driving device 8 can be rapidly terminated, and the trunk positioning of the magnetic head 5 can be maintained accurately at all times.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the structure of a conventional magnetic disk device.
FIG. 2 is a sectional view showing an example of a magnetic disk device equipped with a double header plate to reduce deformation of the header plate due to mechanical vibrations generated in the magnetic disk device;
FIG. 3 is a sectional view showing the structure of an embodiment based on the present invention. In the figure, 1 is a magnetic disk and 2 is a spindle. 3 is a head plate, 4 is a ball bearing, 5 is a magnetic heel 1 to 6
7 is a trolley, 8 is a head drive device. 9 is a stator, 10 is a mover, and 11 is a servo magnetic head. 12 is a dustproof cover, 13 is a cover, 14 is a metal spring, 1
5 indicates a mechanical vibration damping material.

Claims (1)

[Claims] In a configuration consisting of a magnetic disk rotation mechanism, a write/read mechanism, an access mechanism, and a control unit, a mechanical vibration damping member is fixed to the head drive device of the access mechanism using an elastic member fixed to the inner surface of a cover having a predetermined thickness. 1. A magnetic disk drive, comprising: a mechanical vibration damping mechanism that quickly damps mechanical vibrations generated by movement of the access mechanism by press-contacting the access mechanism.