JPS6339176A - magnetic disk device - Google Patents

Abstract

PURPOSE:To prevent the resonance of a carriage and head arm at head seeking time and to prevent the head crush by providing a balancer on the fixing part to fix the upper part of a rotary shaft via a bearing. CONSTITUTION:The vibration caused on the mechanism system (the vibration system consisting of a head arm 13 and carriage 8) to support a head is vibrating in the seeking direction of a head arm 13 side, when the head seeks. Now, the caused vibration is absorbed with the balancing that a weight is held in the opposite direction thereof and that the elastic body 19 of a balancer 18 is made a vibration absorbing spring. In this way, the resonance due to the proper vibration of the carriage 8 and head arm 13 is eliminated, a head touch can be prevented and the stopping accuracy of the carriage 8 is improved.

Description

[Detailed Description of the Invention] [Summary] In the carriage structure of a magnetic disk device, etc., by providing a balancer on the fixed part that fixes the upper part of the rotating shaft via a bearing, the carriage and head arm during head seek can be fixed. This prevents resonance and prevents head crashes.

C. Industrial Application Field] The present invention relates to a carriage structure for a magnetic disk device.

Recently, as the recording density of magnetic disk drives has improved, the flying height of a head flying above a disk rotating at high speed has been reduced further to 0.2 .mu.m or less. Therefore, due to the resonance between the carriage and the head arm, the head and disk disk may come into contact with each other, easily causing a head crash. Therefore, there is a need for a carriage structure that does not cause head cracks.

[Conventional technology]

FIG. 4 shows a sectional view of a conventional magnetic disk device, in which a spindle 5 is held by a bearing 3.4 fixed on a base 2.
A spindle housing 6 is fixed integrally therewith. A motor M is fixed to the lower end of the spindle 5, and a plurality of disks 7 are stacked on a spindle housing 6 at the upper end. Further, a carriage 8 is fixed on the base 2 to which a head arm 13 having a head (not shown), which is disposed opposite to the disk disk 7, is fixed.

FIG. 5 shows a sectional view of a conventional carriage, in which a lower part of a rotating shaft 10 is fixed on a base 2 via a bearing 9, and a screw 2 is attached to the base 2 at the upper part of the rotating shaft 10.
1 is supported by a sub-base 11 via a hair ring 12. A head arm 13 having a head (not shown) at the tip of the rotating shaft 10 is attached to the carriage 8 via a head mounting plate 14, and the carriage 8 and the rotating shaft 10 are fixed to each other. has. Further, a preload spring 16 for applying preload to the bearing 12 is supported by the sub-base 11, and its upper portion is clamped by a fixing portion 17.

[Problems to be Solved by the Invention] In the conventional carriage structure, the head arm 13 and carriage 8 are vibrating systems, and the fixed part 17 and sub-base 11 are fixed systems. The head arm 13 swings during seek, and when stopped, the vibration system vibrates, causing the fixed system to vibrate.

The vibrations are suppressed using a servo control circuit. However, since the sub-base 11 is fixed to the base 2 with two screws, the carriage 8 is not completely supported. Therefore, the damping of vibrations of the fixed system (fixed part 17 and sub-base 11) is slow, and the accuracy of stopping the carriage is reduced. Furthermore, 500Hz
The vibration at the position oscillates, causing the head arm 13 and carriage 8 to resonate, and the head hits the disk disc.
There were problems such as head crashes.

[Means for solving problems]

FIG. 1 is a diagram illustrating the present invention in detail.

The present invention is directed to the fixed part 17 of the carriage 8 or the sub-base 1.
1, a balancer 18 for preventing resonance of the carriage 8 and head arm 13 is provided with an elastic body 19 interposed in the carriage structure of the present invention. Note that 2 is a base, 10 is a rotating shaft, 11 is a sub-base, and 19 is an elastic body.

[Effect]

That is, the mass m2 of the balancer 18 with respect to the mass m1 of the center of gravity iG of the sub-base 11 (not stopped by the sub-base 11) is the elastic By using the body 19 as a vibration damping spring (with a spring constant of 2) and attaching it to the fixed part 17 of the carriage 8, which is the vibration system, or to the sub-base 1, the vibration frequency that vibrates in the theta direction and excites the vibration system. The vibration absorption system m2. 2 is formed to absorb the vibration of the iml.

In other words, with respect to the force that excites the vibration system, a force m2xK2 of equal magnitude and in the opposite direction acts on the fixed system, canceling it out and thereby absorbing the vibration.

〔Example〕

FIG. 2 is a diagram showing an embodiment of the present invention, and FIGS. 3(A) and 3(B) are diagrams showing an embodiment of the balancer of the present invention. Note that the same parts are given the same reference numerals throughout the plan.

In FIG. 2, the lower part of the rotating shaft 10 of the carriage 8 is fixed on the base 2 via a bearing 9 as in the conventional case, and the upper part of the rotating shaft 10 is fixed to the sub-base 11 fixed to the base 2 with a screw 21. , are supported via bearings 12. The head arm 1 is attached to the rotating shaft 10 as in the conventional case.
3 is attached to the gear ridge 8 via the head mounting plate 14, the carriage 8 and the rotating shaft 10 are fixed, and the rotating shaft 10
It has a VCM at the bottom.

Also, a preload spring 16 for applying preload to the bearing 12.
There is a fixing part 17 for fixing the preload spring 16.

In the present invention, a balancer 19 is provided on the fixed portion 17 of the carriage 8 or the subbase 11 to prevent resonance due to the natural vibration of the head arm 13 and the carriage 8.

FIGS. 3(a) and 3(b) show specific shapes of the balancer provided in the fixing portion 17. FIG. The balancer 18 is made of a material such as stainless steel, and is similar to the conventional carriage fixing part 17.
It is provided on the outer periphery of the housing via an elastic body 19 such as rubber. For example, the outer periphery of the balancer 18 is φ1101mm and the thickness is 8mm, a hole A = φ66mm is drilled inside the balancer 18 at a position 18mm away from the center of the balancer 18, and an elastic material (such as rubber) is inserted into the hole A. ) 19 and the outer periphery of the elastic body 19 is adhered to the fixed part 17. 22 is a hole for fixing to the sub-base 11.

In a magnetic disk drive, when the head seeks, the vibration generated in the mechanical system (vibration system consisting of the head arm 13 and the carriage 8) that supports the head vibrates evenly in the left and right directions in the figure. Instead, it vibrates in the theta direction on the head arm 13 side. Therefore,
In the present invention, the generated vibrations can be absorbed by providing a weight in the opposite direction and using the elastic body (eg, urethane rubber, etc.) 19 as a vibration absorbing spring for balance.

This eliminates resonance due to natural vibrations of the carriage 8 and head arm 13, prevents head touching, and improves the precision with which the carriage 8 stops.

Note that the carriage fixing portion 17
The amount of shift is determined by the size of the balancer 18 and the thickness of the elastic body 19, so the optimum value may be determined by experiment.

Although not shown, the balancer provided on the sub-base 11 is also a balancer with an elastic body similar to that described above, and the same effect as described above can be achieved by balancing the elastic body as a vibration-absorbing spring and absorbing vibrations generated during seek. Obtainable.

〔Effect of the invention〕

As described above, according to the present invention, head touching can be prevented by providing a balancer on the fixed portion of the carriage via an elastic body to prevent resonance of the carriage and head arm during seek.

[Brief explanation of the drawing]

Fig. 1 is a diagram for explaining the present invention in detail; Fig. 2 is a diagram showing an embodiment of the invention; Figs. 3 (a) and (b) are diagrams showing an embodiment of the balancer of the invention; FIG. 4 is a sectional view of a conventional magnetic disk device, and FIG. 5 is a sectional view of a conventional carriage. In the figure, 2 is the base, 8 is the carriage, 9.12 is the bearing, 10 is the rotating shaft, 11 is the sub-base, 13 is the head arm, 14 is the head mounting plate, ←→→→→→- 17 is the fixed part, 18 is a balancer, 19 is an elastic body, and 21 is a screw.

Claims (1)

[Claims] The head arm (13) is connected to the rotation axis (1) of the carriage (8).
0), one end of the rotating shaft (10) is fixed to the base (2) via a bearing (9), and the other end is fixed to the base (2) via a bearing (9).
The bearing (1) is attached to the sub-base (11) fixed to the
2), wherein the carriage (8) is fixed to the fixed part on the other end side of the rotating shaft.
and a balancer (18) for preventing resonance due to natural vibration of the head arm (13).