JPH0362376A - Arm stop holding device for magnetic head - Google Patents

Abstract

PURPOSE:To maintain the stop state of an arm strongly when a magnetic had is kept on a CSS zone by adopting a permanent magnet having plural sets of laminators each comprising layers of opposite polarities stacked alternately for at least one magnetic pole. CONSTITUTION:A 1st magnetic piece 12 is a member made of soft magnetic iron and the width of its counter face 12a is made narrower than the width of is bonding face 12a. A 2nd magnetic piece 13 opposite to the piece 12 has two sets of combinations of permanent magnets 13a, 13b in which opposite poles are stacked and bonded adjacent to each other and the width of the counter face 13d is made narrower the same as the case with the counter face 12a. When a magnetic head 20 moves from the R/W zone to the CSS zone and a magnetic disk 30 stops turning, the counter faces 12a, 13d of the 1st magnetic piece 12 and the 2nd megnetic piece 13 are opposed to each other in parallel with a minute gap 8 and an arm 11 keeps the stop state with the action of a strong attaching force between the two magnetic pressure 12,13.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic head arm stop maintenance device, and more particularly, to a magnetic head arm stop maintenance device that maintains a rotary type arm supporting a magnetic head in a stopped state. Regarding equipment.

[Prior Art] Generally, a magnetic disk drive includes a spindle motor system mechanism that supports and rotates a plurality of magnetic disks, and a guide and actuator that guides a magnetic head and moves it to a required position on the magnetic disk. system mechanism (carriage and positioner). There are two methods of supporting and guiding the magnetic head: a linear method that uses linear motion;
There is a rotary type arm that uses circular arc motion, and the present invention relates to a rotary type arm.

Recent magnetic disk drives have adopted a contact start/stop method (hereinafter referred to as RCSS method 2) in order to improve the recording density of magnetic disks. In this C8S method, when the magnetic disk stops rotating, the magnetic head is moved to a specific area (hereinafter referred to as
rcss zone). When the magnetic disk is rotating, the airflow generated by the rotation causes the magnetic head to fly. The CSS zone is provided on the magnetic disk surface outside (inner periphery IPI or outer periphery) of an area where information is written and read (hereinafter referred to as rR/W zone). In this way, since the magnetic disk is provided with the C8S zone and the R/W zone, when the magnetic disk is stopped, the magnetic head always contacts the C8S zone and never contacts the R/W zone. Therefore, damage to the R/W zone due to contact of the magnetic head, so-called head crash, can be prevented.

However, if there is no means to maintain this state when the magnetic head is in contact with the C8S zone, vibrations, impact forces, etc. will be applied to the magnetic disk device when it is transported or moved, and the magnetic The head may move while in contact with the magnetic disk, damaging the R/W zone.

A conventional device for preventing such a problem will be explained with reference to FIG. Incidentally, FIG. 1 is a plan view showing an embodiment of the arm stop keeping device for a magnetic head of the present invention.
As will be described later, the present invention and the prior art are the same in appearance, with the only difference being the lateral paths of the magnetic pole pieces. Therefore, the conventional technique will be explained using FIG. 1.

The figure shows a device 10 for maintaining a rotary arm 11 in a stationary state. The arm stop maintenance device 10 includes a first magnetic piece 12 attached to the arm 11.
and a second magnetic piece 13 attached to a frame (not shown) of the magnetic disk device. A magnetic head 20 is mounted on the tip of the arm 11. This arm 11 rotates around a shaft 55 and can move the magnetic head 20 to a predetermined position on the magnetic disk 30.

Furthermore, a mounting portion 11a for the first magnetic piece 12 is provided on the contour of the arm 11 near the shaft 55. A first magnetic piece 12 is attached to this attachment portion 11a. The first magnetic piece 12 and the second magnetic piece 13 constitute a magnetic lock part, and this magnetic lock part is
When the magnetic head 20 comes to the C8S zone on the inner circumferential side of the magnetic disk 30 and stops, the arm 11 is fixed so as to maintain the stopped state.

FIG. 4 shows an exploded perspective view of this magnetic lock section.

The first magnetic piece 12 is a member made of magnetic soft iron, and is fixed to a flat plate 16 also made of magnetic soft iron.

The adhesive surface (mounting surface) 12b of the first magnetic piece 12 is the flat plate 16
It is fixed with adhesive etc. The width of the opposing surface 12a of the first magnetic piece 12 is narrower than the adhesive surface 12b.

On the other hand, the second magnetic piece 13 has two permanent magnets 13a, 13
Consists of b. These permanent magnets are stacked and bonded so that opposite poles touch each other. The adhesive surface 13c is fixed to the mounting plate 14 with an adhesive or the like, and the width of the opposing surface 13d is narrower than the width of the adhesive surface 13c. The widths of the surfaces of the first magnetic piece 12 and the second magnetic piece 13 that face each other, that is, the facing surface 12a and the facing surface 13d, are equal in width. The mounting plate 14 is screwed to the frame so as to satisfy the following conditions.

(1) When the magnetic head 20 comes to the center of the C8S zone, the opposing surface 12a of the first magnetic piece 12 faces the opposing surface 13d of the second magnetic piece 13 in parallel.

(2) Maintain a certain minute distance δ between opposing surfaces.

In this way, since the minute interval δ is maintained, the first magnetic piece 12 and the second magnetic piece 13 do not come into direct contact with each other.
An attractive force acts between the second magnetic piece 13 and the first magnetic piece 12. At this time, the magnetic helad 20 comes into contact with the C3S zone and is in a stopped state.

[Problems to be Solved by the Invention] The above-mentioned attraction force is effective in maintaining the arm 11 in a stopped state against a certain degree of vibration or impact from outside the magnetic disk device. However, if larger vibrations or shocks are applied, this suction force will no longer be able to keep the arm 11 in a stopped state. Then, the magnetic head 20 mounted on the arm 11 may move over the magnetic disk 30 while in contact with it, and the R/W zone of the magnetic disk 30 may be damaged.

To prevent this, it is possible to increase the size of the opposing surfaces of the two magnetic pieces to strengthen the attractive force.

However, if the width of the opposing surface is made wider than this, this attractive force will affect the positioning of the magnetic head 20 when positioning the magnetic head 20 in the vicinity of the C8S zone of the R/W zone.

An object of the present invention is to provide an arm stop maintenance device that does not affect the positioning of the magnetic head and has a strong holding force when holding the magnetic head in the C8S zone.

[Means for Solving the Problems] In order to achieve the above object, a magnetic head arm stop maintenance device according to the present invention has the following features.

In a device that maintains a rotary arm that supports a magnetic head in a stopped state, a first magnetic piece attached to the arm and a part other than the arm, when the arm is in a stopped state, It has a second magnetic piece that faces the first magnetic piece with a gap therebetween, and at least one of the first magnetic piece and the second magnetic piece is a permanent magnet, and the permanent magnet has: It is characterized in that it is constructed by arranging a plurality of sets of joined bodies stacked so that opposite poles are in contact with each other.

[Embodiment] Next, a magnetic head arm stop keeping device of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a plan view showing an embodiment of the magnetic head arm stop keeping device of the present invention.

The arm stop maintenance device 10 includes a first magnetic piece 12 attached to a mounting portion 11a on the contour of the arm 11, and a mounting plate 14.
It has a second magnetic piece 13 attached to.

FIG. 2 shows an exploded perspective view of the magnetic lock section composed of the first magnetic piece 12 and the second magnetic piece 13.

This magnetic lock part functions to fix the arm 11 so that the magnetic head 20 can maintain a stopped state within the C8S zone measured around the circumference of the magnetic disk 30.

The first magnetic piece 12 is a member made of magnetic soft iron, and is fixed to a flat plate 16 also made of magnetic soft iron.

The adhesive surface (mounting surface 12b) of the first magnetic piece 12 is the flat plate 16
It is fixed with adhesive etc. The width of the facing surface 12a of the first magnetic piece 12 is narrower than the width of the adhesive surface 12b.

The second magnetic piece 13 has two sets of permanent magnets 13a and 13b that are stacked and joined together such that opposite poles are in contact with each other. The adhesive surface 13c of the second magnetic piece 13 is
It is fixed to the mounting plate 14 with adhesive or the like. Further, the width of the opposing surface 13d of the second magnetic piece 13 is narrower than the width of the adhesive surface 13c. The widths of both opposing surfaces 12a and 13d are equal, as indicated by W in FIG.

The width of the adhesive surface 13c of the second magnetic piece 13 is determined by the width of the opposing surface 13c.
Since the width is wider than the width of the opposing surface 13d, the magnetic density passing through the opposing surface 13d is greater than when the width is the same as the opposing surface 13d. Furthermore, as the number of combinations stacked and joined such that the opposite poles of the second magnetic pieces touch each other increases, the density passing through the opposing surface 13d also increases proportionally. Therefore, the attractive force between the two magnetic pieces 12, 13 becomes stronger.

Moreover, since it is not necessary to widen the width of the opposing surface, the range in which this suction force acts does not become very wide in the width direction.

The mounting plate 14 is screwed to the frame so as to satisfy the following conditions.

(1) When the magnetic head 20 comes to the center of the C8S zone, the opposing surface 12a of the first magnetic piece 12 faces parallel to the opposing surface 13d of the second magnetic piece 13.

(2) A small gap δ between the facing surface 12a and the facing surface 13d
keep it.

Next, the operation of this embodiment will be explained.

First, the magnetic head 20 performs R/W on the magnetic disk 30.
Assume that the device is located on the zone and is performing an information write or read operation. When this operation is finished,
Or, if the electricity supply stops during this operation,
The magnetic head 20 starts moving from the R/W zone to the C8S zone.

When entering the C8S zone, an attractive force begins to act between the second magnetic piece 13 and the first magnetic piece 12. Until this time, the magnetic head 20 is in a state floating above the surface of the magnetic disk 30 because the magnetic disk 30 is rotating. The magnetic head 20 moves in the C8S zone L until the first magnetic piece 12 and the second magnetic piece 13 face each other. When the magnetic disk 30 stops rotating, the magnetic head 20 comes into contact with the C8S zone and stops in this state.

Here, even if vibrations or shocks are applied from outside the magnetic disk drive, the arm 11 maintains its stopped state due to the strong attractive force between the two magnetic pieces. Therefore, the magnetic head 20 remains stopped on the C8S zone,
It never moves.

As a result, the R/W zone will not be damaged.

When the magnetic head 20 is on the R/W zone, the two magnetic pieces 12.13 are sufficiently far apart, so the attractive force between the two magnetic pieces 12.13 does not affect the positioning operation of the arm 11. Not affected.

In the above embodiment, only the second magnetic piece 13 is made a permanent magnet, but both the first magnetic piece 12 and the second magnetic piece 13 may be made permanent magnets. It is not necessary to arrange the polarity of the permanent magnets so that an attractive force is generated between the magnetic piece 12 and the second magnetic piece 13.

Note that when the arm is in a stopped state, the facing surface 12a of the first magnetic piece 12 and the facing surface 13d of the second magnetic piece 13 do not need to completely match and oppose, that is, partially. According to experimental results, the attractive force is stronger when the two opposing surfaces are offset to some extent in the width direction. That is, when the two magnetic pieces 12 and 13 are deviated by 1/2 of the width W of the opposing surfaces, the attractive force reaches its maximum value. The positional relationship between the two magnetic pieces 12 and 13 at this time is shown in FIG.

[Effects of the Invention] As explained above, the present invention provides a bonded structure in which at least one of the first magnetic piece and the second magnetic piece is a permanent magnet, and the permanent magnets are stacked so that the magnetic pieces are opposite to each other and are in contact with each other. By arranging a plurality of sets of bodies, it is possible to increase the attraction force between the two magnetic bodies without significantly increasing the influence of the attraction force in the width direction. As a result, even when vibration or impact force is applied from outside the magnetic disk drive, the arm can be maintained in a predetermined stopped state more firmly than in the prior art.

[Brief explanation of drawings]

FIG. 1 is a plan view showing an embodiment of the magnetic head arm stop keeping device of the present invention. FIG. 2 is an exploded perspective view of a magnetic lock section composed of a first magnetic piece and a second magnetic piece. FIG. 3 is a partially enlarged plan view of the magnetic lock section. FIG. 4 is an exploded perspective view of a conventional magnetic lock section. 10 Arm stop maintenance device 12 First magnetic piece 12b Adhesive surfaces 13a, 13b Permanent magnet 13d Opposing surface Arm a Opposing surface Second magnetic Piece C...adhesive surface

Claims (1)

[Claims] In a device for maintaining a rotary arm supporting a magnetic head in a stopped state, a first magnetic piece attached to the arm and a part other than the arm are attached to the arm, and the arm is in a stopped state. In some cases, the magnet has a second magnetic piece that faces the first magnetic piece with a gap therebetween, and at least one of the first magnetic piece and the second magnetic piece is a permanent magnet; 1. A magnetic head arm stop/maintaining device, characterized in that the permanent magnet is constructed by arranging a plurality of sets of bonded bodies stacked so that opposite poles are in contact with each other.