JPS62214565A - Runaway stopping device for magnetic head positioning mechanism - Google Patents

Abstract

PURPOSE:To prevent the damage of a voice coil at the time of the runaway of a rocking body in low temperature and to ensure floating stability of a magnetic head by forming a stopper using an elastic material and projecting contact parts that function independently in multistep. CONSTITUTION:A stopper 14 is constituted by being separated to the first and second step contacts 14a, 14b. Accordingly, when the whole stopper 14 is hardened under low temperature, a voice coil 3 comes into contact only with the first step 14a. However, rigidity is relatively small because of two step form, and collision acceleration can be made small. Consequently, the floating stability of a magnetic head 1 can be ensured. When the rocking body 5 goes to the runaway in case ambient temperature is high and the hardness of the whole stopper 14 is small, the voice coil 3 comes into contact with the first step 14a of the stopper 14 at first, and then comes into contact with the second step 14b. Accordingly, the damage due to collision of the voice coil 3 to a magnet 9 can be prevented as well. Further, the floating stability of the magnetic head 10 can be ensured since the rigidity becomes small.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a runaway stopping device for a magnetic head positioning mechanism, and particularly to a runaway stopping device for a magnetic head positioning mechanism. Regarding a runaway stop device.

[Conventional technology]

One type of magnetic head positioning mechanism for a magnetic disk drive is a swing type that positions the magnetic head by rotating a swinging body that supports the magnetic head.

8 and 9 are, for example, Utility Model Application No. 57-38379
1 is a perspective view and a plan view of a conventional runaway stop device for a swing-type magnetic head positioning mechanism as disclosed in Japanese Patent Publication No.

The oscillating magnetic head positioning mechanism shown in these figures is
Oscillating body 5, housing 8, and voice coil motor 10
It is equipped with

The oscillating body 5 includes an arm 2 that supports the magnetic head 1.
, a voice coil 3 , and a support section 4 that supports these arms 2 and voice coil 3 . Further, the rocking body 5 is arranged vertically via a rotating shaft 6 supported by the housing 8, and is attached to be rotatable around the rotating shaft 6.

The rotating shaft 6 is supported by a housing 8 via a bearing 7.

The voice coil motor 10 has a magnet 9. This magnet 9 is fixed to the housing 8.

The housing 8 is fixed to a base (not shown) with bolts 11.

In the magnetic head positioning mechanism, the oscillator 5 is rotated around the rotating shaft 6 by the magnetic action of the magnet 9 and the voice coil 3 of the oscillator 5, thereby positioning the magnetic head 1 on a magnetic disk (not shown). It is designed to be positioned at a desired position.

By the way, with this magnetic head positioning mechanism, there is no problem during normal operation of the voice coil motor IO, but a runaway stop device is installed to prevent the voice coil 3 from colliding with the magnet 9 when the oscillator 5 runs out of control during abnormal operation. has been done.

The conventional runaway stop device is as shown in Figs. 8 and 9.
For mounting the side opening type on the housing 8, the member 13 is fixed,
This attachment is constructed by attaching two stoppers 12 to the inside of the member 13.

The stopper 12 is formed in the shape of a single short column from a resilient material such as rubber, and prevents the voice coil 3 from colliding with the magnet 9 by receiving the end face of the voice coil 3. .

Furthermore, the flying stability of the magnetic head 1 is ensured by a runaway stopping device that utilizes the characteristics of the stopper 12 made of the material having elasticity.

[Problem that the invention seeks to solve]

Incidentally, in recent years, the access time of magnetic head devices has been shortened and the range of operating temperature conditions has become wider.

On the other hand, as can be seen from FIG. 10, the elastic material of the stopper 12 has a temperature characteristic in which it becomes abnormally hard in the low temperature range of 0 to 5 degrees Celsius. In other words, the rigidity of the stopper 12 becomes extremely large.

As a result, as shown in FIG. 11, with the single short column-shaped stopper 12 used in the conventional runaway stopping device, the collision acceleration at low temperatures becomes extremely large. Therefore, in the conventional runaway stop device, when the oscillator 5 runs out of control due to abnormal operation of the voice coil motor 10, there is a problem in that the voice coil 3 cannot be prevented from being damaged, and the flying stability of the magnetic head 1 cannot be guaranteed. arise.

An object of the present invention is to provide a magnetic head positioning mechanism that can solve the problems of the prior art, reliably prevent damage to the voice coil when the oscillator runs out of control even at low temperatures, and ensure flying stability of the magnetic head. The purpose of the present invention is to provide a runaway stop device.

[Means for solving problems]

In order to achieve the above object, in the present invention, a stopper is attached to the runaway prevention position of the rocking body, and this stopper is made of a resilient material and has a shape in which contact parts that function independently of each other protrude in multiple stages. is formed.

When the rocking body runs out of control, the contact portion and the rocking body are configured to come into contact with each other while increasing the number of contact stages sequentially.

[Effect]

In the present invention, when the oscillator runs out of control, the number of contact steps of the oscillator in contact with the contact portion of the stopper increases sequentially, so that the first contact between the contact portion of the stopper and the oscillator Area is small.

Therefore, it is possible to reduce the collision acceleration at the time of initial contact between the contact part of the stopper and the oscillator, thereby ensuring that the voice coil is not damaged when the oscillator runs out of control, even at low temperatures such as 0 to 5 degrees Celsius. The flying stability of the magnetic head can be guaranteed.

Additionally, when the usage environment becomes high temperature, the number of contact stages between the stopper's contact part and the oscillator increases when the oscillator runs out of control, increasing the contact area, so damage to the voice coil can also be prevented in this case. , and the flying stability of the magnetic head can be guaranteed.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

1A and 1B are a partially cutaway side view and a front view of an embodiment of the present invention, and FIG. 2 is a perspective view of a magnetic head positioning mechanism including a runaway stop device of the present invention.

In the runaway stop device of the embodiment shown in these figures, the rocking body 5
A side opening type mounting member 13 is fixed to the housing 8 supporting the voice coil motor 10.

Two stoppers 14 are attached to the mounting member 13 so as to face each other. The end face of the voice coil 3 comes into contact with this stopper 14 when the oscillator 5 runs out of control.

The stopper 14 is made of an elastic material such as rubber. Further, the stopper 14 includes first and second contact portions 14a and 14b each having a short cylindrical shape. The first stage contact portion 14a is the second stage contact portion 14.
It is formed to have a smaller diameter and a longer length than b, and is formed in the above-mentioned 1.
The contact portion 14a of the second stage.

14b are combined concentrically. A groove 14 is provided between the first and second contact portions 14a and 14b.
c is provided, and the first-stage contact portion 14a and the second-stage contact portion 14b are formed so as to function independently of each other.

The configuration of the magnetic head positioning mechanism shown in FIG. 2 is the same as that shown in FIGS. 8 and 9, and the same members are designated by the same reference numerals and further explanation will be omitted. .

Next, Fig. 3 is a load-deflection diagram of the stopper of the runaway stopping device shown in Figs. 1 (A) and (B), and Fig. 4 is a collision acceleration-temperature diagram of the same. The operation of the runaway stop device of the above embodiment will be explained with reference to FIG.

When the voice coil motor 10 malfunctions and the oscillator 5 goes out of control, the voice coil 3 comes into contact with one of the two stoppers 14.

Here, the stopper 14 is made of a material having elasticity, and the contact portions 14 of the first stage and the second stage function independently of each other.
a and 14b, and the first stage contact portion 1
4a is formed longer than the second-stage contact portion 14b, the voice coil 3 first contacts the first-stage contact portion 14a, and the rocking body 5 is stopped. As a result, collision of the voice coil 3 with the magnet 9 can be reliably prevented, and damage to the voice coil 3 can be prevented.

Moreover, the stopper is the contact portion 14a of the first stage and the second stage.
, 14b. Therefore, when the entire stopper 14 is hard at a low temperature of, for example, 0 to 5° C., the voice coil 3 contacts only the first stage contact portion L4a, so the contact area is small. Therefore, as can be seen from FIG. 3, the rigidity of the stopper 14 is smaller than that of a single short columnar one, and therefore the collision acceleration can be reduced. As a result, the flying stability of the magnetic head 1 can be guaranteed.

If the oscillator 5 runs out of control when the ambient temperature is high and the hardness of the stopper 14 as a whole is small, the voice coil 3 will initially contact the first stage of the stopper 14, as can be understood from FIG. contact portion 14a, and then contact portion 14 of the second stage.
contact b. Therefore, when the oscillator 5 runs out of control at high temperatures, the number of contact steps of the voice coil 3 with the stopper 14 increases sequentially, and the contact area becomes larger. Therefore, in this case as well, damage caused by the collision of the voice coil 3 with the magnet 9 can be reliably prevented, and the rigidity is reduced.
The flying stability of the magnetic head 1 can be guaranteed.

Next, FIGS. 5, 6, and 7 are perspective views showing various other embodiments of the stopper constituting the runaway stopping device of the present invention.

The stopper 15 of the embodiment shown in FIG. 5 is constructed by concentrically combining short prismatic first and second contact portions 15a and 15b. Then, the first stage contact part 1
5a and the second stage contact portion 15b.

A groove 15c is formed in the first and second contact portions 1.
5a and 15b are designed to function independently of each other.

Further, in the stopper 16 of the embodiment shown in FIG. 6, the first and second contact portions 16a and 16b in the shape of short prisms are integrally formed. The first contact portion 16a is formed to have a longer length than the second contact portion 16b. Said 1
A groove 16c is formed between the contact part 16a of the first stage and the contact part 16b of the second stage, and the contact part 16 of the first stage and the second stage
a and 16b function independently of each other.

Furthermore, in the stopper 17 shown in FIG.
The contact parts 17a and 17b of the second stage and the second stage are attached using members (
(omitted in FIG. 7) are arranged and fixed in parallel. The first contact portion 17a is longer than the second contact portion 17b.

A gap 17c is provided between the first and second contact portions 17a and 17b.

Regarding the operation of the other configuration 9 of the embodiment shown in FIGS. 5, 6, and 7, see FIG. 1(A).

It is similar to the stopper shown in (B).

Moreover, although the stoppers shown in FIGS. 1A and 1B and FIGS. 5 to 7 are all constructed in two stages, they may be constructed in three or more stages.

Further, in an embodiment in which the stopper is constructed by combining separately formed contact parts, as shown in FIG. 7, the first contact part is made of a comparatively softer material, and The contact portions after the first stage may be sequentially made of a harder material.

〔Effect of the invention〕

According to the present invention described above, the stopper attached to the runaway stop position of the oscillator supporting the magnetic head is
The contact parts that function independently of each other are formed in a protruding shape in multiple stages using a material having elasticity, and when the rocking body runs out of control, the contact parts and the rocking body come into contact with each other while increasing the number of contact stages one by one. The contact area of the stopper that comes into contact when the rocking body runs out of control is divided into multiple stages, so even if the stopper hardens at low temperatures, the contact area between the rocking body and the stopper is small, so the rigidity is maintained. is small. Therefore, the collision acceleration when the oscillator runs out of control can be reduced, which has the effect of reliably preventing damage to the voice coil when the oscillator runs out of control even at low temperatures, and improves the flying stability of the magnetic head. It has the effect of ensuring that

[Brief explanation of drawings]

FIGS. 1(A) and (B) are a partially cutaway side view and a front view showing an embodiment of the stopper of the runaway stopping device of the present invention, and FIG. 2 is a runaway shown in FIGS. 1(A) and (B). A perspective view of a magnetic head positioning mechanism including a stop device, FIG. 3 is FIG. 1(A),
(B) is a load-deflection diagram of the stopper of the runaway stopping device, FIG. 4 is a collision acceleration-temperature diagram of the same, and FIGS. 5, 6, and 7 are other diagrams of the stopper of the runaway stopping device of the present invention. FIG. 8 is a perspective view of a magnetic head positioning mechanism including a conventional runaway stop device; FIG. 9 is a perspective view showing various embodiments of the present invention;
10 is a load-deflection diagram of the stopper of the conventional runaway stopping mechanism, and FIG. 11 is a collision acceleration-temperature diagram of the same. 1...Magnetic head, 3...Voice coil, 5...
Rocking body, 8...Housing, 9...Magnet, 1
0... Voice coil motor, 13... Stopper mounting member, 14, 15.16.17... Stopper constituting runaway stop device, 14a, 14b; 15
a, 15b; 16a, 16b: 17a, 17b
. . . contact portions of the first and second stages forming the stopper, 14c, 15c, 16c… grooves between the contact portions of the first and second stages, 17c… the same gap.

Claims (1)

[Claims] 1. In a runaway stop device for a magnetic head positioning mechanism in which a stopper is attached to a runaway prevention position of an oscillator supporting a magnetic head, the stopper is made of a resilient material and is a contact portion that functions independently of each other. runaway of a magnetic head positioning mechanism, characterized in that the contact portion and the oscillator are formed in a shape that protrudes in multiple stages, and when the oscillator runs out of control, the contact portion and the oscillator come into contact with each other while sequentially increasing the number of contact stages. Stop device.