JPH04167279A - Levitation type magnetic head - Google Patents

Abstract

PURPOSE:To make sure of a high reliability at the time of CSS by providing a levitation rail whose surface is a crown shape on the levitating surface of a slider facing a disk, and forming a wide groove on the opposite surface in a direction perpendicular to the levitation rail. CONSTITUTION:A groove 5 is formed on a slider 1 in a direction perpendicular to a levitation rail 4 on the opposite side surface to the rail 4, and when the rail surface 4 is formed, a groove bottom 5a is not supported by a jig reference surface 6, but protrusions 7 at both sides of the groove 5 are supported to form a both-side supporting beam. In this state, when the rail surface 4 is finished in a flat state under pressure, the rail surface 4 becomes flat in a state that a part not supported by the jig but levitated in the air is deformed by deltaby the application of a load. When the load and a surface plate are removed in this state, the deformation delta of the bottom 5a is returned to the original state, the flat surface of the rail 4 at the time of forming is simultaneously bent in a protruding surface by delta to form the rail surface 4 of a crown shape. Thus, the reliability of a magnetic head at the start and stop of contact (CSS) with a hard disk can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application J The present invention relates to a flying magnetic head used for hard disk drives.

In floating magnetic heads, with the demand for high-density recording, the flying height of hard disks is becoming lower, and the contact start/stop (CS)
(S) In order to improve the reliability of disk drives, the flying rail surface of the magnetic head facing the hard disk is required to have a precisely smooth surface. Specifically, it is desired that the floating rail surface of the magnetic head has a flatness of about 0.1 n or less, and the shape of the floating rail surface is designed to prevent adsorption during contact without causing as much damage to the hard disk as possible. To avoid this, it is desired that the crown shape be slightly curved into a convex surface.

"Prior Art" By the way, among the conventional magnetic heads for hard disk drives, a composite magnetic head called a composite head is as shown in FIGS. 9, 10, and 11, and FIG. 9 is a plan view thereof. , FIG. 10 is a side view, and FIG. 11 is a front view.

In this composite magnetic head, a magnetic core 102 made of a magnetic material such as Mn-Zn ferrite is bonded to a slider 101 made of a non-magnetic material such as calcium titanate with lead glass 103, and then an air flow is created on the air bearing surface. The floating rail surface 104 bulging in the inflow direction is finished smooth. Regarding the shape of this floating rail, please refer to JP-A-62-2
No. 09713, JP-A-62-209714,
JP-A-62-189617, JP-A-62-173
617, JP-A-62-75927, JP-A-62-71021, JP-A-1-128281, JP-A-1-146117, and the like.

[Problems to be Solved by the Invention] The floating rail surface 104 is a flat surface and has a shape that improves the reliability when starting and stopping the contact of the magnetic head to the hard disk. In order to avoid as much damage as possible to the hard disk and to avoid adhesion upon contact, it is desired that the crown shape be slightly convexly curved as shown in FIG.

However, a processing method for forming a crown shape has not been established at present, and it is difficult to process all floating rail surfaces 104 of the slider 101 into a crown shape.

``Means for Solving the Problems j'' Therefore, in view of the above circumstances, the present invention forms the air bearing surface of the magnetic head in a so-called crown shape that is slightly curved in a convex shape, and makes contact between the magnetic head and the hard disk. In order to improve reliability during start and stop, a groove is formed in advance on the slider in a direction perpendicular to the floating rail on the surface opposite to the floating rail, and then the protrusions on both sides of the groove are supported to improve the surface of the floating rail. The width of the groove should be selected to be equal to or greater than the total length of the slider.

``Operation'' When machining the floating rail surface, the groove bottom is not supported by the jig reference surface, but the protrusions on both sides of the groove are supported to form a double-supported beam. When the surface of the floating rail is finished flat while being pressurized in this state, the part that is floating in the air without being supported by the jig due to the presence of the groove (
When the groove bottom portion) is deformed by δ due to the load, the floating rail surface becomes almost flat. When the load and surface plate are removed in this state, the deformation δ at the groove bottom returns to its original state, and at the same time, the floating rail surface, which was flat during machining, curves into a convex shape by δ, forming a crown-shaped floating rail surface. will be done.

This final deformation amount δ depends on the shape of the slider, the material of the surface plate,
Determined by the load applied during processing. During actual processing, it is possible to obtain the desired amount of deformation δ by varying the weight.

"Embodiments" The present invention will be described in detail below based on specific embodiments shown in the accompanying drawings.

Figures 1, 2, and 3 show floating composite magnetic heads, in which a magnetic core 2 is attached to a glass 3 slider 1 made of non-magnetic ceramic.
Bond with.

A floating rail 9 is formed on the surface of the slider I on the disk (not shown) side. The floating rail surface 4 sandwiched between the air inflow end edge 9a and the air outflow end edge 9b of the floating rail 9 has a slightly convex crown shape. The height of this crown shape (deformation amount of the micro-convex crown) δ is, for example, 20 to 30 nIl.

Furthermore, a groove 5 is formed in a direction perpendicular to the floating rail 9 on the surface of the slider 1 opposite to the surface on which the floating rail surface 4 is formed.

The groove 5 has a width l that is two or more lengths with respect to the entire length of the slider 1.

Next, a method for forming the crown-shaped floating rail surface 4 will be explained. The formation of the crown-shaped floating rail surface 4 is as follows:
After the magnetic core 2 is attached to the slider 1, the floating rail surface 4 is formed by a finishing process.

As shown in FIG. 4, the surface opposite to the floating rail surface 4 is attached to the jig reference surface 6. At this time, the groove bottom 5a does not contact the jig reference surface 6, but the protrusions 7 on both sides of the groove 5 do, so that the groove bottom floats in the air, similar to a double-supported beam, and is not pressurized. The bottom portion of the groove can move up and down by a minute amount δ. In this state, the surface of the floating rail surface 4 is finished flat while being pressurized.

Thereafter, when the load is removed, the surface changes to a convex shape by the amount of deflection, and the floating rail surface 4 takes on a crown shape, as shown in FIG.

In this example, we took up a composite magnetic head that combines a non-magnetic ceramic slider and a magnetic core, but the same applies to a monolithic magnetic head in which the slider part is entirely made of magnetic material (ferrite) and a thin-film head. In addition, by forming a groove perpendicular to the floating rail on the surface opposite to the floating rail surface, the floating rail surface can be formed into a crown shape.

The width l of the groove 5 of the present invention is set to be equal to or more than 3 of the total length of the slider 1, as shown in FIG.

The width l of the groove 5 is equal to the total length 1 of the slider 1, for example, 4.47
It has a width of 4.0 sm, which is more than 3 in 1. Thereby, it is set so that the full 5 is easily bent by the load from the floating rail surface 4 side. Now, if the width i of the groove 5 is less than 2 of the total length of the slider 1, deflection will not occur unless a considerable load is applied, and the loading conditions for forming the crown-shaped floating rail surface 4 will be difficult. , it is difficult to form a stable crown-shaped floating rail surface 4.

Further, the depth d of the groove 5 is at least the variation amount δ of the crown shape, for example, 30 nm or more.

On the other hand, the one shown in FIG.
There is a structure in which the groove width is 1. is small, and the groove depth do is also deep in order to accommodate and attach the support fittings.

In the above example, a groove was formed in the direction perpendicular to the floating rail on the surface opposite to the floating rail surface of the slider, but a groove 15 in the direction parallel to the floating rail was added to form a cross-shaped groove. Similar effects can be expected in the case of FIG.

"Effects of the Invention" According to the present invention, since the floating rail surface of the slider has a crown shape, it is possible to ensure accuracy during C3S.

Further, according to the present invention, a crown shape can be easily obtained by simply changing the shape of the slider without changing conventional lapping methods, jigs, or the like.

Furthermore, according to the present invention, the size of the crown can be controlled depending on the magnitude of the applied load, so it is easy to obtain an appropriate crown shape.

[Brief explanation of drawings]

FIG. 1 is a side view of the magnetic head according to the present invention, FIG. 2 is a bottom view of FIG. 1, FIG. 3 is a front view of FIG. 1, and FIG. 4 shows deformation of the magnetic head during processing according to the present invention. Fig. 5 is a side view of the magnetic head which assumes a crown shape after the flat surface processing in Fig. 4 and the load is removed, and Fig. 6 shows the width and depth of the groove of the magnetic head of the present invention. 7 is a side view of a magnetic head having a support fitting mounting groove, FIG. 9 is a plan view of a conventional magnetic head, FIG. 10 is a side view of FIG. 9, FIG. 11 is a front view, FIG. 12 is a longitudinal sectional view showing an example of an ideal round shape. 4... Floating rail surface 6... Jig reference surface 5...
Groove 7...Protruding part 5a...Groove
Figure 1 Figure 3 Figure 4 Figure 5 7 5a 5 / Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 +03 Figure 12 Procedures (Forms) 1. Case Indication of 1990 Patent Application No. 294044 2゜ Name of the invention Floating magnetic head 3, Relationship to the case of the person making the amendment Patent applicant address 22 persons, 5, Higashino Kitainoue-cho, Yamashina-ku, Kyoto City
Name (663) Kyocera Co., Ltd. Representative Ito
Kensuke 4, Agent Address: 6, 1-23-26 Edobori, Nishi-ku, Osaka City, Column 7 for a brief explanation of the drawings in the specification subject to the amendment, "Conventional Top view of the magnetic head,
'', then add ``Figure 8 is a bottom view of a magnetic head with cross-shaped grooves.''. that's all

Claims (2)

[Claims] (1) In a floating magnetic head having a slider floating above a rotating disk, the slider has a floating rail with a crown-shaped surface on the floating surface facing the disk, and the opposite surface is perpendicular to the floating rail. A magnetic head characterized by having wide grooves formed in the direction of the magnetic head. (2) The magnetic head according to claim 1, wherein the width of the groove is 1/2 or more of the total length of the slider.