JP2006192536A - Surface finishing device and method, dimple die and head suspension - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To carry out specular-surface-finishing of a stereoscopic surface of a work. <P>SOLUTION: This surface finishing device is constituted of a jet nozzle 3 to jet jetting of a water jet 9 to a recessed surface of a dimple die 11 and a fine particle supply pipe 5 to supply fine particles to collide against the recessed surface by the water jet 9 and surface-finishes the recessed part in a specular shape by colliding the fine particles against the recessed part by the water jet 9 and hits the water jet 9 against the whole of the recessed surface by movably supporting the dimple die 11 at this time, and characteristically, jetting speed of the jet is made within a range of 200 m/sec to 1000 m/sec and a grain diameter of the fine particles is made within a range of 6 nm to 100 nm. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a surface finishing apparatus and method for performing surface finishing of a dimple die for pressing a dimple of a head suspension of a disk device incorporated in an information processing apparatus such as a computer, a surface finished dimple die, and a surface finish The head suspension is press-processed with a dimple die.

  The head of a magnetic disk drive (HDD) that uses a hard disk is such that the slider slightly floats on the hard disk that rotates at high speed, and data is written to the hard disk via a transducer built in the slider. Read. For this reason, the slider is supported by the head suspension and can float from the hard disk.

  In this head suspension, a slider is supported by a tongue at the tip of the flexure, and dimples are provided on the load beam to support the slider while applying a load. This dimple is formed into a spherical surface by press molding on the load beam, and the slider is supported by the dimple in a state where the head suspension is lifted. In this state, the slider is allowed to swing when the disk is rotated. Smooth operation can be performed.

  Therefore, the spherical surface of the dimple is required to have extremely high accuracy.

  Here, the press working of the dimple is performed by using a dimple die having a spherical processing concave surface, and the concave surface of the dimple die is formed by electric discharge machining. On the concave surface due to electric discharge machining, there is adhesion of low melting point compounds and generation of micro cracks, and the surface roughness is extremely rough with Ra = 300 to 400 nm in terms of the center line average roughness related to the amplitude of the irregularities, which is improved. Was desired.

  On the other hand, surface finishing can also be performed using conventional liquid honing and dry honing techniques. In the liquid honing treatment, a surface finish is performed by spraying an abrasive having a particle diameter of about 8 μm with running water at about 30 to 60 m / s. In the dry honing, an abrasive having a particle size of about 6 μm is sprayed together with air to finish the surface.

  However, in liquid honing, there is a problem that the usable particle size is about 8 μm, and if the particle size is smaller than this, the abrasive is condensed in the aqueous solution, resulting in a large particle size. In dry honing, the abrasive floats in the air, making it difficult to maintain a good working environment.

Japanese Patent Laid-Open No. 62-24969

  The problem to be solved is that there is a limit to the mirror-like surface finish of the three-dimensional surface of the workpiece.

  In order to enable a mirror-like surface finish of a three-dimensional surface, the present invention impinges on the three-dimensional surface of a workpiece with a water jet supply unit that injects a water jet, and collides with the surface by the water jet. The most important feature is that the surface is finished in a mirror surface by causing the fine particles to collide with the surface by the water jet.

  The surface finishing apparatus according to the present invention includes a water jet supply unit that injects a water jet onto a three-dimensional surface of a work, and a fine particle supply unit that supplies fine particles that collide with the surface by the water jet. Thus, the surface finish is mirror-finished by causing the fine particles to collide with the surface by the water jet, so that the mirror-like surface finish can be surely performed.

  The object of enabling a mirror-like surface finish of the three-dimensional surface of the workpiece was realized by using fine particles dispersed in a water jet and an aqueous solution.

[Surface finishing equipment]
FIG. 1 is a schematic diagram of a surface finishing apparatus according to Embodiment 1 of the present invention.

  As shown in FIG. 1, the surface finishing apparatus 1 includes a jet nozzle 3, a fine flow supply pipe 5, and a work table 7.

  The jet nozzle 3 constitutes a water jet supply unit, is connected to a pressure water supply source, and injects the water jet 9 onto the three-dimensional surface of the workpiece. The jet speed of the water jet 9 is set in the range of 200 m / sec to 1000 m / sec, for example.

  The fine particle supply pipe 5 constitutes a fine flow supply unit, is connected to a supply source of an aqueous solution in which fine particles are dispersed, and is coupled to the jet nozzle 3 so as to be finely connected to the water jet 9 in advance. An aqueous solution 10 in which grains are dispersed is supplied. As the fine particles, for example, ultra-fine diamond (UDD “Ultra-Dispersed Diamonds”) is used, and the particle size is set in the range of, for example, 6 nm to 100 nm as the minimum particle size that can be granulated.

The work table 7 is provided so as to be inclined by an angle θ with respect to the jet axis A of the jet nozzle 3, and can be driven to rotate about the inclined rotation axis C and move in a direction parallel to the rotation axis C. Yes. A dimple die 11 as a work can be supported on the work table 7. With this support, the dimple die 11 that is a work is movably supported, and the water jet 9 can be applied to the entire processing concave surface that is a three-dimensional surface of the dimple die 11.
[Dimple Die]
2 to 5 relate to a dimple die, FIG. 2 is a cross-sectional view, FIG. 3 is a plan view, FIG. 4 is a main part enlarged plan view, and FIG. 5 is a main part enlarged cross-sectional view.

As shown in FIGS. 2 to 5, the dimple die 11 as a workpiece is formed in a columnar shape and has a concave surface 13 for processing at the center. The concave surface 13 corresponds to the size of the dimple to be processed.
[Surface finish]
The dimple die 11 shown in FIGS. 2 to 5 has a concave surface 13 formed by electric discharge machining. In the state of this electric discharge machining, there is adhesion of a low melting point compound or generation of micro cracks on the concave surface 13, and the surface roughness is extremely rough with Ra = 300 to 400 nm in terms of the center line average roughness related to the amplitude of the unevenness. .

  Next, the surface finishing apparatus 1 in FIG. 1 performs a mirror-like surface finishing by causing fine particles to collide with the concave surface 13 of the dimple die 11 by the water jet 9.

  In FIG. 1, a dimple die 11 after electric discharge machining is centered and supported on a work table 7.

  While jetting the water jet 9 from the jet nozzle 3, the work table 7 is reciprocally translated in the S direction while rotating around the rotation axis C.

  The aqueous solution 10 in which the fine particles are dispersed by the water jet 9 is sucked out of the fine particle supply pipe 5 by the ejecting action, and sprayed onto the dimple die 11 on the work table 7 together with the water jet 9. Since the work table 7 reciprocally translates in the S direction while rotating about the rotation axis C as described above, fine particles are formed on the entire concave surface 13 of the dimple die 11 by the jet of the jetted water jet 9. Can collide.

  The fine particles can be dispersed in an aqueous solution by using fine particles that are made so that the fine particles do not increase in size even if the fine particles have a particle size in the range of 4 nm to 100 nm. it can. Further, the fine particles are ultrafine diamond, and the condensation of the fine particles can be reliably suppressed. Therefore, the collision of fine particles to the entire concave surface 13 of the dimple die 11 can be reliably performed.

Due to such collision of fine grains, the concave surface 13 of the dimple die 11 can be made into a mirror-like surface finish. The surface roughness of the concave surface 13 is, for example, Ra = 30 nm.
[Head suspension]
FIGS. 6 to 8 relate to a head suspension in which dimples are press-molded by the dimple die 11 having the mirror-like concave surface 13, FIG. 6 is a plan view of the head suspension, and FIG. FIG. 8 is a plan view of the essential part of the SA-SA arrow in FIG.

  As shown in FIGS. 6 to 8, the head suspension 15 includes a load beam 17, a base portion 19, and a flexure 21.

  The load beam 17 applies a load to the head 23 and includes a rigid body portion 25 and a spring portion 27. The rigid body portion 25 is made of, for example, stainless steel, and has a relatively large thickness, for example, about 100 μm.

  The spring portion 27 is formed separately from the rigid body portion 25, and is made of, for example, a thin stainless steel rolled plate having a spring property. Its spring constant is lower than that of the rigid body portion 25, and the accuracy is low. It has a spring constant. The plate thickness of the spring portion 27 is set to about t = 40 μm, for example. One end of the spring portion 27 is fixed to the rear end portion of the rigid body portion 25 by laser welding or the like. A reinforcing plate 29 is provided integrally with the other part of the spring part 27.

  The base portion 19 has a base plate 31. The base plate 31 is superimposed on the reinforcing plate 29 and fixed to each other by laser welding or the like. Therefore, the base plate 31 is reinforced by the reinforcing plate 29 to form the base portion 19. The base portion 19 is attached to the carriage arm and is driven to rotate about an axis. Accordingly, the base portion 19 has an arm side configuration that elastically supports the load beam 17.

  The flexure 21 has a conductive wiring 33 formed on the surface of a metal substrate such as a thin rolled stainless steel plate having spring properties via an electric insulating layer, and is fixed to the rigid body portion 25 by laser welding or the like. One end of the conductive wiring 33 is conductively connected to a writing / reading terminal 35 of the head 23, and the other end is extended to the base portion 19 side.

  The head 23 is provided with a tongue 37 in a cantilever manner. The tongue 37 is in contact with the dimple 39 on the load beam 17 side. The height of the dimple 39 is about 70 μm, and the degree of freedom of swinging of the head 23 is maintained by the tongue 37 coming into contact with the dimple 39. The tongue 37 is equipped with a slider 41 for writing and reading shown in FIG. The slider 41 is provided with a terminal corresponding to the terminal 35 and is conductively connected to each other.

  The dimple 39 is press-molded by the dimple die 11 having the mirror-like concave surface 13 after the load beam 17 is formed by etching or the like.

  Therefore, the tongue 37 and the slider 41 can be swung by the dimple 39 when the head suspension 15 is lifted by the rotation of the disk. The dimple 39 was press-molded by the dimple die 11 having the mirror-like concave surface 13, so that the spherical surface of the dimple 39 could be formed with extremely high accuracy. For this reason, the dimple 39 can support the slider 41 accurately through a tongue 37 while applying a load to the slider 41. As a result, information can be accurately written to and read from the disk by the slider 41, and durability can be improved.

  Since the fine particles are caused to collide with the water jet 9 while being dispersed in the aqueous solution 10, the fine particles are not scattered in the air, and the working environment can be maintained satisfactorily.

  As described above, the jet nozzle 3 (water jet supply unit) that injects the jet of the water jet 9 onto the concave surface 13 (three-dimensional surface of the workpiece) of the dimple die 11 and the concave surface 13 by the water jet 9. A fine-grain supply pipe 5 (fine-grain supply part) for supplying ultra-fine diamond (fine grains) to be collided with the water, and the water jet 9 causes the ultra-fine diamond to collide with the concave surface 13 to form a mirror-like surface. Finishing can be done.

  The fine particle supply pipe 5 is connected to the jet nozzle 3 (water jet supply unit) and supplies the aqueous solution 10 in which the ultrafine diamond is dispersed in advance to the water jet 9. The aqueous solution 10 can be easily sucked and can be made to collide with the concave surface 13 without condensing fine particles.

  Since the water jet 9 can be applied to the entire concave surface 13 by movably supporting the dimple die 11 (work), the mirror surface finish of the concave surface 13 can be surely performed.

  Since the fine particles have a particle size in the range of 4 nm to 100 nm, the mirror-like surface finish of the concave surface 13 can be surely performed.

  The concave surface 13 for processing the dimple die 11 that press-molds the dimple 39 of the head suspension 15 in the hard disk device is mirror-finished by the surface finishing device 1 so that the press molding of the dimple 39 is accurately performed. Can be done.

  Since the dimple 39 of the head suspension 15 is pressed by the dimple die 11, the information can be accurately written and read by the slider 41 on the disk, and the durability can be improved.

  FIG. 9 is a schematic diagram of a surface finishing apparatus according to a second embodiment of the present invention. The basic configuration is the same as that of the first embodiment, and the same or corresponding components are denoted by the same reference numerals or the same reference numerals with an A.

  As shown in FIG. 9, in the surface finishing apparatus 1 </ b> A of this example, the fine particle supply unit was a container 5 </ b> A filled with an aqueous solution 10 </ b> A in which fine particles were dispersed around the water jet 9.

  The surrounding aqueous solution 10 </ b> A is drawn by the water jet 9, and the aqueous solution 10 </ b> A in which fine particles are dispersed is sprayed onto the dimple die 11 on the work table 7 together with the water jet 9.

  Therefore, this embodiment can achieve the same effects as those of the first embodiment.

  Further, in this embodiment, the aqueous solution 10A is simply stored in the container 5A, and the structure is simple.

  In each of the above embodiments, ultrafine diamond that can be dispersed in an aqueous solution as fine particles is used, but other fine particles can be used as long as they can be dispersed in an aqueous solution.

  The present invention can be applied not only to the mirror-like surface finishing of dimples but also to the mirror-like surface finishing of other three-dimensional surfaces.

It is the schematic of a surface finishing apparatus (Example 1). (Example 1) which is sectional drawing of a dimple die. (Example 1) which is a top view of a dimple die. (Example 1) which is a principal part enlarged plan view of a dimple die. (Example 1) which is a principal part expanded sectional view of a dimple die. (Example 1) which is a top view of a head suspension. FIG. 3 is an enlarged plan view of a main part of the head suspension (Example 1). (Example 1) which is SA-SA arrow sectional drawing of FIG. It is the schematic of a surface finishing apparatus (Example 2).

Explanation of symbols

1,1A Surface finishing device 3 Jet nozzle (water jet supply unit)
5 Fine grain supply pipe (fine grain supply section)
5A container (fine grain supply unit)
7 Work table 9 Water jet 10, 10A Aqueous solution 11 Dimple die (work)
15 head suspension 17 load beam 21 flexure 23 head 37 tongue 39 dimple 41 slider

Claims (9)

A water jet supply section for injecting a water jet on the three-dimensional surface of the workpiece;
A fine particle supply unit that supplies fine particles that collide with the surface by the water jet,
A surface finishing apparatus characterized in that the fine particles collide with the surface by the water jet to perform a mirror finish. The surface finishing device according to claim 1,
The surface finishing apparatus, wherein the fine particle supply unit is a fine particle supply pipe connected to the water jet supply unit and supplying an aqueous solution in which the fine particles are dispersed in advance to the water jet. The surface finishing device according to claim 1,
The surface finishing apparatus, wherein the fine particle supply unit is a container filled with an aqueous solution in which the fine particles are dispersed around the water jet. The surface finishing apparatus according to any one of claims 1 to 3,
A surface finishing apparatus characterized in that the water jet can be applied to the entire three-dimensional surface by movably supporting the workpiece. The surface finishing device according to any one of claims 1 to 4,
The fine particle has a particle size in a range of 4 nm to 100 nm. A dimple die characterized in that the processing concave surface for press-molding the dimples of the head suspension in the hard disk drive is mirror-finished by the surface finishing device according to any one of claims 1 to 5. . 7. A head suspension, wherein the dimple is pressed by the dimple die according to claim 6. A surface finishing method characterized in that a fine surface collides with a three-dimensional surface of a workpiece by a water jet to perform a mirror finish. The surface finishing apparatus according to any one of claims 1 to 5,
A surface finishing method characterized in that a fine grain collides with the three-dimensional surface of the workpiece by the water jet to perform a mirror surface finish.

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