JPH01301049A - Working method for magnetic head and jig - Google Patents

Abstract

PURPOSE:To easily form a floating face having a projecting curvature on a magnetic head by exerting moment so that the floating face becomes recessed on the back face parallel to the floating face and flat, flatly lapping by a flat surface plate and releasing it. CONSTITUTION:An inline type magnetic head 7 is bonded by a hot adhesive onto a flat back face 1 in a yoke type deformable block 8. An uniform moment is then transferred to the back face 1 of the block 8 by operating a deforming bolt 4 to deform in a recessed shape the floating face 27 of the magnetic head 7 fixed to this back face 1. Then, after flatly lapping this floating face 27 by a flat surface plate this moment is released to make this floating face 27 projecting. The crowning of the inline type magnetic head can thus be easily performed.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a crown processing jig and a crown processing method for the air bearing surface of a magnetic head of a fixed magnetic disk device used as a storage device of a computer. .

[Conventional technology]

With the increase in magnetic recording density, the flying height of the magnetic head has decreased to 0.
It is becoming smaller to 3 μm. For this purpose, the air bearing surface of the magnetic head and the recording medium surface of the magnetic disk must be finished smooth. However, when stopping a storage device, the rotation of the disk is stopped and the head is grounded on the disk, so if both surfaces are smooth, they will stick together, making it impossible to remove them with the starting torque of the motor that rotates the disk. .

In order to prevent this adsorption, processing is performed to finish the flying surface of the head into a cylindrical surface having a convex curvature in its longitudinal direction (flying direction of the head) (referred to as crown processing).

This is shown in FIG. A surface plate 2 having a cylindrical surface 20 with a concave curvature caused by a deforming bolt 4 attached to the center line B of the fixed block 3. A monolithic magnetic head 1 having an air bearing surface that has been previously processed to be flat is lapped on top of the air bearing surface while moving in the direction of arrow A, thereby transferring the concavities of the surface plate 2 onto the air bearing surface.

However, in the monolithic magnetic head 1, which is designed so that the magnetic rotation gap 5 for recording and reproducing is formed not at the most protruding center part of the convex air bearing surface 21 but at the edge part, wobbling occurs in the gap part. , a fatal drawback arises in that the apparent flying height increases.

Further, as shown in FIG. 8(a), there is also a pawl groove 1 to which the suspension of the monolithic magnetic head 22 is attached.
The floating surface 24, which is deformed into a concave shape by the reaction force of the spring 6 attached to the spring 4 and the moment caused by E, is shown in FIG. 8(b).
Another method is to move the surface plate 23 in the C direction so that it becomes flat and wrap it, and then release the moment restraint, resulting in a convex air bearing surface 25 as shown in Figure 8 (C). (For example, JP-A-61-199765).

Further, the tension of a wire may be used instead of the spring 6.

The above-described processing method shown in FIG. 8 was effective for the magnetic head 1.22 in which the pawl groove portion 14 was formed. However, in order to downsize magnetic disk drives, heads (typically the in-line type magnetic head 7 shown in FIG. 6), in which the suspension is mounted with the suspension changed from a direction perpendicular to the air bearing surface to a direction parallel to the air bearing surface, have been installed. It has come into use in recent years.

[Problem that the invention seeks to solve]

Unlike the conventional monolithic magnetic head 1, this in-line magnetic head 7 does not have pawl grooves 14 formed on the surface parallel to the air bearing surface to lower the fulcrum in order to prevent pitching of the head. Since there is no pawl groove 14, the processing method shown in FIG. 8 cannot be applied to the in-line magnetic head 7 shown in FIG. 6.

SUMMARY OF THE INVENTION An object of the present invention is to provide a processing method and apparatus for providing an air bearing surface with a convex curvature to a head (for example, an in-line magnetic head 7) having a flat back surface parallel to the air bearing surface.

[Means for solving problems]

The present invention applies a moment to the flat back surface parallel to the air bearing surface so that the air bearing surface becomes concave, wraps it flat on a flat surface plate, and after releasing it, the air bearing surface becomes convex. A method for manufacturing a magnetic head and a jig therefor, characterized by:

The above moment may be a moment using mechanical deformation or a moment using chemical deformation of an adhesive or the like. Since the back surface of the head is flat, the moment from the jig to the head is transmitted using adhesive.

[Example] (Example 1) Figure 1 is an example of a jig that generates a moment using mechanical deformation and transmits the moment to the back surface of the magnetic head 7 via adhesive to deform the head. .

A yoke-shaped deformable block 8 made of an aluminum-magnesium alloy such as A3056, a mold steel such as 5KD11, or an aluminum-copper alloy such as A2017 is connected to the groove 26 by the deformation bolt 4 and a screw made in the deformable block 8. Expand.

Then, the moment is uniformly transmitted to the plane I of the block 8, and the plane I is deformed into a concave shape.

Here, the deformation bolt 4 is preferably harder than the block 8, such as SCM435, for durability against repeated use. Further, in order to prevent the threaded portion of the block 8 from being plastically deformed by the deforming bolt 4, for example, if the main body is made of aluminum alloy, it is preferable to fit a steel insert screw into the threaded portion of the block 8.

Before deformation, adhere the in-line magnetic head 7 to the plane I with hot melt adhesive, and after fixing, adjust the tightening force P of the deformation bolt 4 while checking the deformation δ of the air bearing surface 27 using an interferometer, etc. do.

At this time, it is preferable that the ratio of the dimension of the block 8 shown in FIG. 1(a) to the dimension h is 0.7<-<1.4 because it is easy to apply a moment.

Further, in order to increase the moment, it is preferable that the size is 1. Dimension 51 dimension l is moment z
b 10 is preferred.

Note that the jigs shown in FIGS. 2 and 3 are conceivable as jigs that generate moments using mechanical deformation. A magnetic head 71 is bonded to a deformable block 81, and is deformed in the direction of the arrow G by the deformation bolt 41 in FIG. 2, and in the direction of the arrow H in the vacuum space 9 evacuated in the direction of the arrow F in FIG. In order to obtain a uniform curvature, the jig shown in FIG. 3 is more preferable than the jig shown in FIG. 2.

Also, a plane I to which the magnetic heads 71 and 72 are attached.

73.74 requires a flatness of about 0.3 μm/30×30 m. This can be easily formed with plastic wrap. Further, in order to prevent the entire structure formed by the blocks 8, 81, 82, etc., that is, the jig 85, from falling down, the structure shown in FIG. 4 can be considered. The deformable jig 85 is deformed by a deforming bolt 45 so that the air bearing surface 76 of the in-line magnetic head 75 becomes concave. This is adhered or fastened to the piston 10 and placed in the cylinder 11 and wrapped. Piston 10 is cylinder 11
The deformable block 8 does not fall down along the inner diameter of the deformable block 8.

(Embodiment 2) FIG. 5(a) is an example of a jig 81 that generates a moment using chemical deformation to deform the back surface 80 of the head 79. Figure 5) shows the cross section XX in Figure 5(a).

A long groove 15 is formed in a flat or round grooved block 13 (the plate material is preferably an aluminum-magnesium alloy such as A3056), and the center line of the air bearing surface is aligned with the center line of the long groove 15 as shown in (a). and place the head 79. When the long grooves 15 are filled with longitudinal adhesive 12 (for example, hot melt adhesive), after fixation, the adhesive in the long grooves 15 contracts and the center portion 82 of the back surface is stretched. This force deforms the back surface 80 of the head 79 into a concave shape as shown in FIG.

〔Effect of the invention〕

According to the present invention, it is possible to easily crown an in-line magnetic head, which has not been possible in the past.

In addition, crowning can be made very easily by simply forming grooves 15 in a jig used for conventional grinding and lapping, as in the grooved block B shown in FIG.
Since the deformation is 1 μm, the dimensions can be kept within the tolerance with a margin even if other grinding processes are added.)

[Brief explanation of the drawing]

1st. 2. 3' and 4 show a jig using a moment using mechanical deformation according to the present invention, and FIG. 5 shows a jig using a moment using chemical deformation. FIGS. 7 and 8 show a conventional crowning method. FIG. 6 shows an in-line magnetic head to which crowning is desired according to the present invention. 2: Surface plate, 4: Deformation bolt, 7: In-line magnetic head, 8: Deformable block, 9: Vacuum space, 10:
Piston, 11 cylinder, 12: adhesive, 13: grooved block, 15: long groove. Figure 1/J Figure 2 Figure 3 Figure 4 Figure 7th Figure 5 Figure 6 Figure 7 Figure 8

Claims (1)

[Claims] 1. In a method for processing a magnetic head having an air bearing surface that is a convex cylindrical surface with a constant curvature and a back surface that is flat and parallel to the chord formed by the cylindrical surface of the air bearing surface, A magnetic head characterized in that a convex air bearing surface is obtained by flatly wrapping the air bearing surface which is deformed into a concave shape by a certain moment applied to the back surface of the magnetic head and releasing the restraint of the moment. Processing method. 2. A jig used in the processing method according to claim 1, wherein the moment according to claim 1 is created by mechanical deformation, and the moment is transmitted to the back surface with an adhesive. 3. A jig used in the processing method according to claim 1, wherein the moment set forth in claim 1 is created by chemical deformation such as shrinkage, and the moment is transmitted to the back surface using an adhesive.