JP2001118231A - Fine positioning actuator, actuator for positioning thin film magnetic head element, and head suspension assembly provided with the actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fine positioning actuator capable of simplifying its assembling operation without obstructing its operation, an actuator for positioning a thin film magnetic head element, and a head suspension assembly provided with the actuator. SOLUTION: In this actuator that utilizes piezoelectric effect and that is intended to position an object by being fixed between the object to be positioned or a magnetic head slider and a supporting mechanism, at least three first projections having a smooth tip end are provided at dispersed positions on the surface on the supporting mechanism side of this actuator; and these first projections are designed to have a height at which the tip end comes into contact with the surface of the supporting mechanism.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an actuator for minutely positioning an object, an actuator for positioning a thin-film magnetic head element used in a magnetic disk drive, and a head suspension assembly provided with the actuator.

[0002]

2. Description of the Related Art In a magnetic disk drive, a magnetic head slider attached to the tip of a suspension of a head suspension assembly is levitated from the surface of a rotating magnetic disk, and in this state, a thin film mounted on the magnetic head slider is mounted. Recording to and / or reproduction from the magnetic disk is performed by the magnetic head element.

In recent years, with the increase in capacity and recording density of magnetic disk drives, the density in the disk radial direction (track width direction) has been increasing, and a conventional voice coil motor (hereinafter referred to as VCM) has been developed. ), It is becoming difficult to accurately adjust the position of the magnetic head.

As one of means for realizing precise positioning of a magnetic head, another actuator mechanism is mounted on the magnetic head slider side in addition to the conventional VCM, so that a fine VCM that cannot be completely followed. This is a technique in which precise positioning is performed by the actuator (for example, JP-A-6-259905, JP-A-6-259905).
309822, JP-A-8-180623).

[0005]

In a head suspension assembly using this type of actuator, it is necessary to assemble the magnetic head slider and the actuator and the gap between the actuator and the suspension so as not to hinder the movement of the actuator. There is. However, providing such a gap not only degrades impact resistance, but also requires special management to keep the gap constant during assembly.

Accordingly, the present invention is to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a micro-positioning actuator and a thin-film magnetic head element which can simplify the assembling work without obstructing the operation of the actuator. An object of the present invention is to provide a positioning actuator and a head suspension assembly provided with the actuator.

[0007]

According to the present invention, there is provided an actuator utilizing the piezoelectric phenomenon for positioning an object by fixing the object between the object to be positioned and a support mechanism. At least three smooth projections are provided at dispersed positions on the surface on the side of the support mechanism, and the first projections are configured to have a height at which the tips contact the surface of the support mechanism. A micro-positioning actuator is provided.

Further, according to the present invention, there is provided an actuator utilizing a piezoelectric phenomenon for positioning a thin-film magnetic head element by being fixed between a magnetic head slider having at least one thin-film magnetic head element and a support mechanism. At least three first protrusions having smooth ends are provided at dispersed positions on the support mechanism side surface of the actuator, and the first protrusions abut on the support mechanism surface. An actuator for positioning a thin-film magnetic head element having a height is provided.

Still further according to the invention, at least one
A magnetic head slider having two thin film magnetic head elements, an actuator fixed to the magnetic head slider and using a piezoelectric phenomenon for positioning the thin film magnetic head element, and an actuator fixed to the actuator and supporting the actuator. Provided is a head suspension assembly including a support mechanism and at least three first projections provided at dispersed positions on a surface of the actuator on the support mechanism side and having a smooth tip contacting the surface of the support mechanism. Is done.

[0010] At least three first projections each having a smooth tip are provided at dispersed positions on the support mechanism side surface of the actuator. These first projections are set at a height at which their tips abut the surface of the support mechanism. Therefore, the positioning in the height direction when the actuator is fixed to the support mechanism becomes very easy, and the assembling work can be simplified. Moreover, almost no friction occurs between the actuator and the support mechanism, and the movement of the actuator is not hindered.

At least three second projections having smooth ends are provided at dispersed positions on the object side or the magnetic head slider side of the actuator, and these second projections are provided on the surface of the magnetic head slider. It is preferable that they are configured to have a height at which their tips abut. This makes it extremely easy to position the object or the magnetic head slider in the height direction when the object or the magnetic head slider is fixed to the actuator, thereby simplifying the assembling work. Moreover, almost no friction occurs between the actuator and the object or the magnetic head slider, and the movement of the actuator is not hindered. Also, when the actuator is fixed to the support mechanism, the actuator can be mounted horizontally on the jig, so that positioning with respect to the parallelism with the jig can be performed very easily.

It is preferable that the height of the first projection is substantially equal to the fixing gap between the actuator and the support mechanism.

It is also preferable that the height of the second projection is substantially equal to the fixed gap between the object or the magnetic head slider and the actuator.

It is preferable that all the second protrusions are provided at positions where they come into contact with the surface of the magnetic head slider.

It is also preferable that two and / or one first projection is provided on the fixed part of the actuator, and two and / or one first projection is provided on the movable part of the actuator.

It is preferable that the first projection and the second projection are formed of a material different from that of the actuator.

[0017]

FIG. 1 is a plan view of an entire head suspension assembly as viewed from the slider side according to an embodiment of the present invention. FIG. 2 is a flexure of an actuator and a magnetic head slider in the embodiment of FIG. FIG. 3 is an exploded perspective view showing an attachment structure to the actuator, FIG. 3 shows the structure of the actuator in the embodiment of FIG. 1, (A) is a plan view seen from the support mechanism side, (B) is a side view, (C) is a bottom view. FIG. 4 is a side view showing a mounting structure of the actuator and the magnetic head slider to the flexure in the embodiment of FIG.

As shown in these figures, in the head suspension assembly, an actuator 11 for precisely positioning a magnetic head element is attached to the tip of a suspension 10, and a slider 12 having a magnetic head element is fixed to the actuator 11. It is composed.

As is well known, the magnetic disk drive is provided with a main actuator (VCM) for displacing the drive arm to which such a head suspension assembly is attached and moving the entire assembly. The actuator 11 is provided to enable a minute displacement that cannot be driven by such a main actuator.

The actuator 11 has a multilayer structure including a piezoelectric / electrostrictive material layer which expands and contracts by an inverse piezoelectric effect or an electrostrictive effect, as will be described later.
Are electrically connected to the suspension 10 electrically and mechanically. Its size is, for example, 1.25
magnetic head slider 1 mm × 1.0 mm × 0.3 mm
The size is almost equal to 2. In this embodiment, the position of the actuator 11
Considering the mechanical and electrical performance of the suspension 10
Are slightly shifted backward from the magnetic head slider 12.

In this embodiment, the actuator 11 and the magnetic head slider 12 are both mounted on the surface of the suspension 10 facing the magnetic disk medium so as to face the surface of the magnetic disk medium. Although not shown, a head driving IC chip may be mounted in the middle of the suspension 10.

The suspension 10 includes the actuator 1
An elastic flexure 13 for supporting the slider 12 with a tongue 16 provided at one end through the flexure 1, a load beam 14 that supports and fixes the flexure 13 and also has an elasticity, It is mainly composed of a base plate 15 provided on the base.

The load beam 14 is connected to the actuator 11
The slider 12 has elasticity to press the slider 12 in the direction of the magnetic disk via the.

On the other hand, the flexure 13 is used for the load beam 1.
Soft tongue 1 pressed by dimples provided on 4
The tongue 16 has elasticity to flexibly support the slider 12 via the actuator 11.
As in the present embodiment, the flexure 13 and the load beam 1
In a suspension having a three-piece structure in which the component 4 is an independent component, the rigidity of the flexure 13 is lower than the rigidity of the load beam 14.

In the present embodiment, the flexure 13 is made of a stainless steel plate (for example, SUS304T) having a thickness of about 25 μm.
A).

On the flexure 13, a flexible wiring member 17 including a plurality of lead conductors in a laminated thin film pattern is formed. That is, the wiring member 17 is a flexible printed circuit (Flexible Print Circuit).
It is formed by the same well-known patterning method as that for forming a printed circuit board on a thin metal plate as in the case of a circuit (a unit such as a unit, FPC). For example, a first insulating material layer made of a resin material such as polyimide having a thickness of about 5 μm, a patterned Cu layer (lead conductor layer) having a thickness of about 4 μm, and a first insulating material layer made of a resin material such as polyimide having a thickness of about 5 μm. 2 are formed by sequentially laminating two insulating material layers in this order from the flexure 13 side. However, in the portion of the connection pad for connecting to the magnetic head element and the external circuit, the Au layer is formed on the Cu layer, and the insulating material layer is not formed thereon.

In this embodiment, the wiring member 17 is
A first wiring member 17a including two lead conductors on one side connected to the magnetic head element and a total of four lead conductors on both sides, and a first wiring member 17a connected on two sides to the actuator 11 and including a total of four lead conductors on both sides. And two wiring members 17b.

One end of the lead conductor of the first wiring member 17 a is connected to the connection pad 1 provided at the tip of the flexure 13.
8 is connected. The connection pad 18 is connected to the terminal electrode of the magnetic head slider 12 by gold bonding, wire bonding, stitch bonding, or the like. The other end of the lead conductor of the first wiring member 17a is connected to a connection pad 19 for connecting to an external circuit.

One end of the lead conductor of the second wiring member 17b is connected to a connection pad formed on the tongue 16 of the flexure 13, and this connection pad is connected to the actuator 1
1 terminal electrode. Second wiring member 17b
The other end of the lead conductor is connected to a connection pad 19 for connecting to an external circuit.

The load beam 14 is formed of an elastic stainless steel plate having a thickness of about 60 to 65 μm and having a shape narrowing toward its tip, and supports the flexure 13 over its entire length. However, the fixing between the flexure 13 and the load beam 14 is performed by pinpoint fixing by a plurality of welding points.

The base plate 15 is made of stainless steel or iron, and is fixed to the base of the load beam 14 by welding. By fixing the base plate 15 with the mounting portion 20, the suspension 1
0 is attached to a movable arm (not shown).
Note that the flexure 13 and the load beam 14 may not be separately provided, and a suspension having a two-piece structure of a base plate and a flexure-load beam may be used.

As shown in more detail in FIG. 2, the actuator 11 has a fixed portion 11a and a movable portion 11b, and further has two rod-shaped displacement generating portions 11c connecting these.
And 11d. Each of the displacement generating units 11c and 11d is provided with at least one piezoelectric / electrostrictive material layer having electrode layers on both sides, and is configured to generate expansion and contraction by applying a voltage to the electrode layers. The piezoelectric / electrostrictive material layer is a piezoelectric / electrostrictive
It is made of an electrostrictive material. The fixed portion 11a has three terminal electrodes 11e to 11g connected to the above-described electrode layers.

In the present embodiment, in particular, FIGS.
As shown in (2), two projections (first projections) 21 of smooth shape and material are provided at positions separated from each other on the upper surface (the surface on the side fixed to the flexure) of the fixed portion 11a of the actuator 11 Two projections (first projections) 22 of smooth shape and material are provided on the lower surface of the movable portion 11b of the actuator 11 (the surface on the side fixed to the magnetic head slider) at positions separated from each other on the upper surface of the portion 11b. The two projections (second projections) 23 having a smooth tip and a material are provided at positions apart from each other at the fixed portion 1 of the actuator 11.
Two projections (second projections) 24 each having a shape and a material whose tip is smooth are formed at positions separated from each other on the lower surface of 1a.

The projections 21, 22, 23 and 24 are
For example, the actuator 11 and the flexure 13 are made of a material such as glass paste or Teflon.
Alternatively, the height is set to a value corresponding to a desired fixing gap with the magnetic head slider 12, usually, a height of about 25 to 35 μm. Further, a film may be formed on the surface of the protrusion formed of any material by using a self-lubricating material such as a fluororesin or DLC (diamond-like carbon) so as to have self-lubricating properties.

As shown in FIG. 4, the upper surface of the fixed portion 11 a of the actuator 11 is adhered to the tongue 16 of the flexure 13 with an adhesive 25. Actuator 1
Other methods of fixing the actuator 1 include:
The terminal electrodes 11e to 11g provided on the fixed portion 11a are soldered to connection pads formed on the tongue portion 16 of the flexure 13, or the terminal electrodes 11e to 11g provided on the fixed portion 11a are connected to the tongue of the flexure 13. The bonding may be performed by using a conductive adhesive to the connection pad formed in the portion 16. The movable portion 11b of the actuator 11
The rear end side of the magnetic head slider 12 (the magnetic head element 12
The lower surface of the predetermined portion 12a on the formation end side of FIG.
It is fixed by being adhered.

As described above, the displacement generators 11c and 11c
d is connected to the flexure 13 via the fixed portion 11a, and the other ends of the displacement generating portions 11c and 11d are connected to the movable portion 11d.
b, it is connected to the slider 12. Therefore, the slider 12 is displaced by the expansion and contraction of the displacement generating portions 11c and 11d, and the magnetic head element is displaced in an arc shape so as to intersect the recording track of the magnetic disk.

Hereinafter, the structure of the actuator 11 will be described in more detail.

When the piezoelectric / electrostrictive material layers in the displacement generating sections 11c and 11d are made of a so-called piezoelectric material such as PZT, the piezoelectric / electrostrictive material layers are usually provided with a polarization treatment for improving the displacement performance. Is given. The polarization direction by this polarization processing is the thickness direction of the actuator 11. When the direction of the electric field when a voltage is applied to the electrode layer matches the polarization direction, the piezoelectric / electrostrictive material layer between the two electrodes expands in the thickness direction (piezoelectric longitudinal effect) and contracts in the in-plane direction. (Piezoelectric lateral effect). On the other hand, when the direction of the electric field is opposite to the polarization direction, the piezoelectric / electrostrictive material layer contracts in its thickness direction (piezoelectric longitudinal effect) and elongates in its in-plane direction (piezoelectric transverse effect). When a voltage that causes contraction is alternately applied to one of the displacement generators and the other displacement generator, the ratio of the length of one displacement generator to the length of the other displacement generator changes. As a result, the two displacement generating portions bend in the same direction within the plane of the actuator 11. Due to this bending, the movable portion 11b swings with respect to the fixed portion 11a in the direction of the arrow 27 in FIG. 2 around the position where no voltage is applied. This swing is caused by the movable part 11b being displaced by the displacement generator 1.
The displacement describes an arc-shaped trajectory in a direction substantially orthogonal to the expansion and contraction directions of 1c and 11d, and the swing direction exists in the plane of the actuator. Therefore, the magnetic head element also swings along an arc-shaped trajectory. At this time, since the direction of the voltage is the same as that of the polarization, there is no fear of the polarization decay, which is preferable. Even if the voltage applied alternately to the two displacement generating portions causes the displacement generating portions to extend, similar swinging occurs.

As the actuator 11, voltages may be simultaneously applied to both displacement generators so as to cause opposite displacements. That is, an alternating voltage may be simultaneously applied to one displacement generating unit and the other displacement generating unit such that when one expands, the other contracts, and when one contracts, the other expands. The swing of the movable portion 11b at this time is centered on the position when no voltage is applied. In this case, the amplitude of the swing when the drive voltage is the same is about twice as large as when the voltage is applied alternately. However, in this case, the displacement generating portion is extended on one side of the swing, and the driving voltage at this time is opposite to the direction of the polarization. Therefore, when the applied voltage is high or when the voltage is continuously applied, the polarization of the piezoelectric / electrostrictive material may be attenuated. Therefore,
By applying a constant DC bias voltage in the same direction as the polarization and superimposing the alternating voltage on the bias voltage as the drive voltage, the direction of the drive voltage does not reverse to the direction of the polarization. To In this case, the swing is centered on the position when only the bias voltage is applied.

The actuator 11 has displacement generating portions 11c and 11d by forming holes and cutouts in a plate of a piezoelectric / electrostrictive material provided with an electrode layer at a predetermined location.
It has a structure in which the fixed portion 11a and the movable portion 11b are integrally formed. Therefore, the rigidity and dimensional accuracy of the actuator can be increased, and there is no fear that an assembly error occurs. Further, since no adhesive is used for manufacturing the actuator itself, no adhesive layer is present in a portion where stress is generated by deformation of the displacement generating portion. Therefore, problems such as transmission loss due to the adhesive layer and aging of the adhesive strength do not occur.

The term "piezoelectric / electrostrictive material" means a material which expands and contracts by an inverse piezoelectric effect or an electrostrictive effect. The piezoelectric / electrostrictive material may be any material as long as it can be applied to the displacement generating portion of the actuator as described above. However, because of its high rigidity, PZT [Pb (Zr, Ti) is usually used.
O ₃ ], PT (PbTiO ₃ ), PLZT [(Pb, L
a) (Zr, Ti) O ₃ ], barium titanate (BaT)
Ceramic piezoelectric / electrostrictive materials such as iO ₃ ) are preferred.

FIG. 5 is a flowchart for explaining one manufacturing process of the head suspension assembly according to the present embodiment.

First, as described above, an actuator 11 made of a piezoelectric material is prepared (step S1).

Next, projections 21 and 22 are formed on the upper surfaces of the fixed portion 11a and the movable portion 11b of the actuator 11, respectively, and the movable portion 11b and the fixed portion 11a are formed.
Are formed on the lower surface of the substrate (step S2). In the present embodiment, these projections 21 and 2
2, 23 and 24 are formed by screen printing a glass paste. That is, the actuator 1 is mounted on the stage.
1 is fixed, and the position enlarged by a microscope is visually checked by an operator, or the position is adjusted by performing automatic position correction by image processing, and a projection made of glass paste is attached by screen printing. Then it is baked. As the baking condition, about 500 to 800 ° C., preferably about 600 to 700 ° C. is adopted in the air. In addition to screen printing, a small amount may be ejected using a dispenser to attach the projection. Further, a fluororesin, DLC, or the like may be formed as a film on the surface of the protrusion formed of any material.

On the other hand, on the suspension side, the flexure 1 of the prepared suspension (step S3) is used.
An adhesive is applied to the bonding portion of the tongue 16 of Step 3 (Step S)
4).

Next, the actuator 11 and the suspension are assembled (step S5), and thereafter, the adhesive is hardened to some extent by irradiating ultraviolet rays, and temporary bonding is performed (step S6).

In the prior art, in order to make the fixing gap between the actuator and the suspension about 30 μm,
It was necessary to insert a spacer between them and assemble them, and strict control was required for the amount and location of the adhesive applied. For this reason, process control is difficult, and the production yield is deteriorated because a spacer and a jig for inserting the spacer are used. However, in the present embodiment, since the four projections 21 and 22 having a predetermined height are formed on the upper surface of the actuator 11, the positioning of the actuator in the height direction at the time of assembly becomes very easy, and the fixing gap and the degree of parallelism are reduced. The management becomes easy and the yield is improved. In addition, it is not necessary to strictly control the amount and location of the adhesive to be applied, so that the process can be easily controlled in that sense.
Moreover, since the four projections 23 and 24 having a predetermined height are formed on the lower surface of the actuator 11, the actuator can be mounted horizontally on the jig even when the actuator 11 is fixed to the flexure 13. Positioning can be performed very easily.

Next, the terminal electrode 1 of the actuator 11
In order to connect 1e to 11g to the connection pad formed on the tongue 16 of the flexure 13, a silver paste is applied to a corresponding portion (step S7), and the silver paste is heated to be baked and the adhesive is completely heated. Cure (Step S
8).

Thereafter, an adhesive is applied to the lower surface of the movable portion 11b of the actuator 11 in the actuator-suspension assembly assembled in this manner (step S9).

Next, the magnetic head slider 12 is mounted on the actuator-suspension assembly to assemble the head suspension assembly (step S10), and thereafter, the adhesive is cured by irradiating ultraviolet rays to a certain degree, thereby temporarily bonding. Performed (step S11)
Thereafter, the adhesive is further heated to completely thermally cure the adhesive (step S12).

In the prior art, as in the case of the actuator and the suspension, in order to reduce the fixing gap between the actuator and the magnetic head slider to about 30 μm, it is necessary to insert a spacer between the two and assemble them. Strict control was required for the amount and location of the adhesive applied. For this reason, process control is difficult, and the production yield is deteriorated because a spacer and a jig for inserting the spacer are used. However, in this embodiment, since the four projections 23 and 24 having a predetermined height are formed on the lower surface of the actuator 11, the positioning of the magnetic head slider and the actuator in the height direction at the time of assembly becomes very easy, and The gap and the parallelism can be easily managed and the yield can be improved. In addition, it is not necessary to strictly control the amount and location of the adhesive to be applied, so that the process can be easily controlled in that sense.

Thereafter, the terminal electrode of the magnetic head slider 12 is connected to the connection pad 1 provided on the tip of the flexure 13.
8 is performed (step S13).

Since the tip of the projection 22 is formed of a smooth shape and material, even when the actuator 11 and the flexure 13 are in contact, almost no friction occurs between them, The movement is hardly hindered. Moreover, since the two projections 22 are provided, an effect of dispersing the load can be obtained.

FIGS. 6A and 6B show the structure of an actuator according to another embodiment of the present invention. FIG. 6A is a plan view seen from the support mechanism side, FIG. 6B is a side view, and FIG. 6C is a bottom view. .

As shown in FIG.
Has a fixed part 61a and a movable part 61b, and further has two rod-shaped displacement generating parts 61c and 61 connecting these parts.
d. The displacement generating portions 61c and 61d are provided with at least one piezoelectric / electrostrictive material layer having electrode layers on both sides, and are configured to generate expansion and contraction by applying a voltage to the electrode layers. The piezoelectric / electrostrictive material layer is made of a piezoelectric / electrostrictive material that expands and contracts by an inverse piezoelectric effect or an electrostrictive effect. The fixed portion 61a is formed with three terminal electrodes 61e to 61g connected to the above-described electrode layers.

In this embodiment, in particular, the actuator 6
Two protrusions (first protrusions) 71 of smooth shape and material are provided at positions apart from each other on the upper surface (the surface on the side fixed to the flexure) of the first fixed portion 61a, and are provided on the upper surface of the movable portion 61b. One protrusion (first protrusion) 72 of a smooth shape and material has a smooth tip at a position separated from each other on the lower surface (the surface fixed to the magnetic head slider) of the movable portion 61b of the actuator 61. And the two projections (second projections) 73 of the material and the fixing portion 6 of the actuator 61.
One projection (second projection) 74 of a shape and material having a smooth tip is formed on the lower surface of 1a.

The projections 71, 72, 73 and 74 are
For example, it is made of a material such as glass paste or Teflon, and its height is set to a desired fixing gap between the actuator 61 and the flexure or the magnetic head slider.
The height is set to a value corresponding to a height of about 35 μm. Further, a film may be formed on the surface of the protrusion formed of any material by using a self-lubricating material such as a fluororesin or DLC (diamond-like carbon) so as to have self-lubricating properties.

Since the tip of the projection 72 is made of a smooth shape and material, even when the actuator 61 and the flexure are in contact, almost no friction occurs between them and the movement of the actuator 61 Is hardly inhibited. In particular, in the present embodiment, since there is only one projection 72, friction is smaller.

The other configuration, operation and effect of this embodiment are completely the same as those of the embodiment of FIG.

FIGS. 7A and 7B show the structure of an actuator according to still another embodiment of the present invention. FIG. 7A is a plan view seen from the support mechanism side, FIG. 7B is a side view, and FIG. is there.

As shown in FIG.
Has a fixed portion 81a and a movable portion 81b, and further has two rod-shaped displacement generating portions 81c and 81
d. The displacement generating sections 81c and 81d are provided with at least one piezoelectric / electrostrictive material layer having electrode layers on both sides, and are configured to generate expansion and contraction by applying a voltage to the electrode layers. The piezoelectric / electrostrictive material layer is made of a piezoelectric / electrostrictive material that expands and contracts by an inverse piezoelectric effect or an electrostrictive effect. The fixed portion 81a has three terminal electrodes 81e to 81g connected to the above-described electrode layers.

In this embodiment, in particular, the actuator 8
On the upper surface of the first fixing portion 81a (the surface on the side fixed to the flexure), one protrusion (first protrusion) of a shape and material having a smooth tip is provided.
The protrusions (first protrusions) 92 of smooth shape and material are provided on the lower surface of the movable portion 81b of the actuator 81 (for the magnetic head slider). Two projections (second projections) 93 of smooth shape and material are provided on the fixed portion 8 of the actuator 81 at positions separated from each other on the surface to be fixed).
One projection (second projection) 94 of a shape and material having a smooth tip is formed on the lower surface of 1a.

The projections 81, 82, 83 and 84
For example, it is made of a material such as glass paste or Teflon, and its height is set to a desired fixed gap between the actuator 81 and the flexure or the magnetic head slider, usually 25 mm.
The height is set to a value corresponding to a height of about 35 μm. Further, a film may be formed on the surface of the protrusion formed of any material by using a self-lubricating material such as a fluororesin or DLC (diamond-like carbon) so as to have self-lubricating properties.

Since the tip of the projection 92 is formed of a smooth shape and material, even when the actuator 81 and the flexure are in contact, almost no friction occurs between them and the movement of the actuator 81 Is hardly inhibited. Moreover, since the two projections 92 are provided, an effect of dispersing the load can be obtained.

The other configuration, operation and effect of this embodiment are exactly the same as those of the embodiment of FIG.

FIGS. 8A and 8B show the structure of an actuator according to still another embodiment of the present invention. FIG. 8A is a plan view seen from the support mechanism side, FIG. 8B is a side view, and FIG. FIG. 9 is a side view showing the mounting structure of the actuator and the magnetic head slider to the flexure in the embodiment of FIG.

As shown in these figures, the actuator 101 has a fixed portion 101a and a movable portion 101b.
Further, two rod-shaped displacement generating sections 10 connecting these are formed.
1c and 101d. Displacement generators 101c and 1
01d is provided with at least one piezoelectric / electrostrictive material layer having electrode layers on both sides, and is configured to generate expansion and contraction by applying a voltage to the electrode layers. The piezoelectric / electrostrictive material layer is made of a piezoelectric / electrostrictive material that expands and contracts by an inverse piezoelectric effect or an electrostrictive effect. The fixing portion 101a has three terminal electrodes 101e to 101e connected to the above-described electrode layers.
01 g are formed.

In this embodiment, in particular, the actuator 1
The first protrusion (first protrusion) 111 of a smooth shape and material is provided on the upper surface (the surface on the side fixed to the flexure) of the fixed portion 101a of the movable portion 101 at a position apart from the upper surface of the movable portion 101b. The two protrusions (first protrusions) 112 having a smooth shape and a material have a smooth tip at positions separated from each other on the lower surface (the surface on the side fixed to the magnetic head slider) of the movable portion 101b of the actuator 101. And two protrusions (second protrusions) 113 of a material and one protrusion (second protrusion) 11 of a shape and material having a smooth tip on the lower surface of one displacement generating portion 101 c of the actuator 101.
4 are formed respectively.

The projections 111, 112, 113 and 1
14 is made of, for example, a material such as glass paste or Teflon, and its height is set to a desired fixing gap between the actuator 101 and the flexure 13 or the magnetic head slider 12, usually a height of about 25 to 35 μm. It is set to the combined value. In addition, a film is formed on the surface of the protrusion formed of any material using a self-lubricating material such as fluororesin or DLC (diamond-like carbon),
It may have self-lubricating properties.

Since the tip of the projection 112 is formed of a smooth shape and material, even when the actuator 101 and the flexure 13 are in contact, almost no friction occurs between them, The movement is hardly hindered. Moreover, two protrusions 11
2, the effect of dispersing the load is also obtained. In the present embodiment, the actuator 1
01 and all the projections 113 and 114 provided on the lower surface side
Is provided at a position where it comes into contact with the surface of the magnetic head slider 12, so that the operation for fixing the magnetic head slider 12 to the actuator 101 in the height direction and achieving the parallelism becomes very easy. Thus, the assembly work can be simplified.

The other configuration, operation and effect of this embodiment are completely the same as those of the embodiment of FIG.

The number of protrusions described above is such that the number of first protrusions provided on the upper surface of the actuator (the surface fixed to the flexure) is three or more, and the lower surface of the actuator (the surface fixed to the magnetic head slider). It is clear that any number of second projections may be provided as long as three or more are provided. Further, the position at which it is provided is arbitrary.
As the number of protrusions provided on the movable portion of the actuator increases, the degree of dispersion of the load increases, but the friction increases accordingly. It is important to form the projections at positions separated from each other to facilitate positioning of the actuator or the magnetic head slider, and to facilitate management of the fixing gap and the parallelism.

The present invention has been described above using the head suspension assembly provided with the actuator for positioning the thin-film magnetic head element. However, the present invention is not limited to such an actuator. The present invention is also applicable to an actuator that minutely positions an object other than the above.

The embodiments described above all show the present invention by way of example and not by way of limitation, and the present invention can be embodied in various other modified forms and modified forms. Therefore, the scope of the present invention is defined only by the appended claims and their equivalents.

[0075]

As described above in detail, according to the present invention, at least three first projections having a smooth tip are provided at dispersed positions on the surface of the actuator on the support mechanism side. Are set at a height at which their tips abut the surface of the support mechanism. Therefore, the positioning when the actuator is fixed to the support mechanism becomes very easy, and the assembling work can be simplified. Moreover, almost no friction occurs between the actuator and the support mechanism, and the movement of the actuator is not hindered.

[Brief description of the drawings]

FIG. 1 is a plan view of an entire head suspension assembly as viewed from a slider side according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing a structure for attaching an actuator and a magnetic head slider to a flexure in the embodiment of FIG. 1;

3A and 3B show a structure of an actuator in the embodiment of FIG. 1; FIG. 3A is a plan view seen from a support mechanism side;
(B) is a side view, and (C) is a bottom view.

FIG. 4 is a side view showing a structure for attaching an actuator and a magnetic head slider to a flexure in the embodiment of FIG. 1;

FIG. 5 is a flowchart for explaining one manufacturing process of the head suspension assembly in the embodiment of FIG. 1;

6A and 6B show a structure of an actuator according to another embodiment of the present invention, wherein FIG. 6A is a plan view as viewed from a support mechanism side, FIG. 6B is a side view, and FIG. 6C is a bottom view.

7A and 7B show a structure of an actuator according to still another embodiment of the present invention, wherein FIG. 7A is a plan view as viewed from a support mechanism side, FIG. 7B is a side view, and FIG. 7C is a bottom view.

8A and 8B show a structure of an actuator according to still another embodiment of the present invention, wherein FIG. 8A is a plan view as viewed from a support mechanism side, FIG. 8B is a side view, and FIG. 8C is a bottom view. .

FIG. 9 is a side view showing a mounting structure of the actuator and the magnetic head slider to the flexure in the embodiment of FIG. 8;

[Explanation of symbols]

10 Suspension 11, 61, 81, 101 Actuator 11a, 61a, 81a, 101a Fixed part 11b, 61b, 81b, 101b Movable part 11c, 11d, 61c, 61d, 81c, 81d, 1
01c, 101d Displacement generators 11e, 11f, 11g, 61e, 61f, 61g, 8
1e, 81f, 81g, 101e, 101f, 101g
Terminal electrode 12 Magnetic head slider 13 Flexure 14 Load beam 15 Base plate 16 Tongue 17 Wiring member 17a First wiring member 17b Second wiring member 18, 19 Connection pad 20 Mounting part 21, 22, 23, 24, 71, 72 , 73, 74, 9
1, 92, 93, 94, 111, 112, 113, 11
4 Projection 25, 26 Adhesive

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Takashi Honda T.D.K., 1-13-1 Nihonbashi, Chuo-ku, Tokyo (72) Inventor Ken Wada T.D.1-1-1 Nihonbashi, Chuo-ku, Tokyo Inside (72) Inventor Mitsuyoshi Kawai 1-13-1 Nihonbashi, Chuo-ku, Tokyo TDK Corporation (72) Inventor Keiichi Soeno 1-13-1 Nihonbashi, Chuo-ku, Tokyo TDK Corporation F term (reference) 5D033 BB14 DA01 DA31 5D042 LA01 MA15 5D059 AA01 BA01 CA01 CA08 DA04 DA26 EA02 EA03 5D096 NN03 NN07

Claims (21)

[Claims] 1. An actuator utilizing a piezoelectric phenomenon for positioning an object by being fixed between an object to be positioned and a support mechanism, wherein a dispersion of a surface of the actuator on a side of the support mechanism is provided. A first projection having at least three smooth tips is provided at a predetermined position, the first projection having a height at which the tip abuts against the surface of the support mechanism. Micro positioning actuator. 2. A second projection having at least three smooth tips is provided at dispersed positions on the object-side surface of the actuator, and the second projection has a tip whose end is the same as that of the object. The actuator according to claim 1, wherein the actuator is configured to have a height abutting on a surface. 3. The actuator according to claim 2, wherein a height of the second protrusion is substantially equal to a fixing gap between the object and the actuator. 4. An actuator utilizing a piezoelectric phenomenon, which is fixed between a magnetic head slider having at least one thin-film magnetic head element and a support mechanism to position the thin-film magnetic head element, wherein the actuator uses a piezoelectric phenomenon. A first projection having at least three smooth tips is provided at dispersed positions on the support mechanism side surface of the actuator, and the first projection has a height at which the tip abuts the support mechanism surface. An actuator for positioning a thin-film magnetic head element, characterized in that: 5. A second projection having at least three smooth tips is provided at dispersed positions on the surface of the actuator on the side of the magnetic head slider.
5. The projection according to claim 4, wherein a tip of the projection has a height at which a tip thereof contacts a surface of the magnetic head slider.
An actuator according to claim 1. 6. The actuator according to claim 5, wherein a height of the second protrusion is substantially equal to a fixing gap between the magnetic head slider and the actuator. 7. The actuator according to claim 5, wherein all the second protrusions are provided at positions where they come into contact with the surface of the magnetic head slider. 8. The actuator according to claim 1, wherein two first protrusions are provided on a fixed portion of the actuator, and two first protrusions are provided on a movable portion of the actuator. 8. The actuator according to any one of items 1 to 7. 9. The actuator according to claim 1, wherein two first projections are provided on a fixed portion of the actuator, and one first projection is provided on a movable portion of the actuator. 8. The actuator according to any one of items 1 to 7. 10. The actuator according to claim 1, wherein one of the first protrusions is provided on a fixed portion of the actuator, and two of the first protrusions are provided on a movable portion of the actuator. 8. The actuator according to any one of items 1 to 7. 11. The actuator according to claim 1, wherein a height of the first protrusion is substantially equal to a fixing gap between the actuator and the support mechanism. 12. The actuator according to claim 1, wherein the first protrusion and the second protrusion are formed of a material different from that of the actuator. 13. A magnetic head slider having at least one thin-film magnetic head element, an actuator fixed to the magnetic head slider and utilizing a piezoelectric phenomenon for positioning the thin-film magnetic head element, and the actuator is fixed. And a support mechanism for supporting the actuator, and at least three of a plurality of support mechanisms provided at dispersed positions on a surface of the actuator on the support mechanism side, the smooth ends of which are in contact with the surface of the support mechanism. A head suspension assembly comprising: a first projection; 14. The actuator according to claim 13, wherein two first protrusions are provided on a fixed portion of the actuator, and two first protrusions are provided on a movable portion of the actuator. A head suspension assembly according to claim 1. 15. The actuator according to claim 13, wherein two first protrusions are provided on a fixed portion of the actuator, and one first protrusion is provided on a movable portion of the actuator. A head suspension assembly according to claim 1. 16. The actuator according to claim 13, wherein one of the first protrusions is provided on a fixed portion of the actuator, and two of the first protrusions are provided on a movable portion of the actuator. A head suspension assembly according to claim 1. 17. At least three actuators are provided at dispersed positions on the surface of the actuator on the magnetic head slider side, at least a part of which is in contact with the surface of the magnetic head slider and has a smooth tip. 17. The head suspension assembly according to claim 13, further comprising a second protrusion. 18. The head suspension assembly according to claim 17, wherein a height of the second protrusion is substantially equal to a fixing gap between the magnetic head slider and the actuator. 19. The head suspension assembly according to claim 17, wherein all the second protrusions are provided at positions where they come into contact with the surface of the magnetic head slider. 20. The head suspension assembly according to claim 13, wherein a height of the first protrusion is substantially equal to a fixing gap between the actuator and the support mechanism. 21. The head suspension assembly according to claim 13, wherein the first protrusion and the second protrusion are formed of a material different from that of the actuator.