JPH02289909A - Magnetic head and production of magnetic head - Google Patents

Abstract

PURPOSE:To improve the wear resistance of the surfaces for contact with media by providing hard joining members which are formed in the respective regulating grooves of a pair of sub-cores and are exposed on the surfaces for contact with media and soft joining members which are formed in the winding groove and joining groove of a pair of the sub-cores and integrally join a pair of the sub-cores. CONSTITUTION:The regulating grooves 22, 22 are respectively formed on both sides of the opposite surfaces of the sub-cores 21a, 21b and the hard joining parts 23 which are high melting glass are formed in the regulating groove 22. The winding groove 24 and joining groove 25 orthogonal with the regulating groove 22 are formed in the one sub-core 21a. Further, the soft joining members 28 which are low melting glass are disposed in a part of the winding groove 24 formed in the sub-core 21a and the joining groove 25. The sub-cores 21a, 21b are integrally joined when the soft joining members 28 are melted. The hard joining members 23 are exposed to the regulating groove 22 part of the surfaces S for contact with media. The wear resistance is improved in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a magnetic head and a method of manufacturing the magnetic head.

(Prior art) In the field of magnetic recording and reproducing, the demand for higher recording densities has increased, and magnetic recording media have had higher coercive force, resulting in higher saturation magnetic flux densities for magnetic head core abrasives, shorter wavelength recording, etc. It is progressing.

Ferromagnetic metals such as Sendas 1 and amorphous are suitable in terms of high saturation magnetic flux density that enables writing to high coercive force recording media, but for playback in high frequency bands, eddy current loss is low. It is well known that ferromagnetic oxides (ferrites) are suitable.

Therefore, various magnetic heads that combine these two types of magnetic materials have been developed.

FIG. 3 shows one of the above-mentioned magnetic heads, the so-called M
1 is a perspective view showing a magnetic head called an IG (Metal In Gap) head.

In the figure, la and lb indicate a pair of subcores formed by Ferrai 1. sub-core la, l
Regulation grooves 2 are formed on both sides of the opposing surfaces of b. Main cores 3a and 3b are formed of a metal magnetic material on opposing surfaces of these sub-cores la and lb. A magnetic gap portion 4 is formed of a non-magnetic material between these main cores 3a and 3b. Also, sub-core]. A glass 5, which is a joining member, is placed in the regulation 2 of a 1 l b, and this glass 5
are melted and the sub-cores 1 a s 1 b are fixed together.

Therefore, in the above-mentioned magnetic head, a high saturation magnetic flux density is obtained because the magnetic flux passes through the main cores 3a and 3b, which are metal magnetic materials, during recording, and a high saturation magnetic flux density is obtained during reproduction because most of the magnetic path is made of ferrite. The playback characteristics are good in the range.

Next, the general manufacturing process of the above-mentioned magnetic head will be explained in the fourth step.
This will be explained using Figures (a) to (f).

First, as shown in FIG. 4(b), regulating grooves 12 are formed at a predetermined pitch on a pair of ferrite blocks 11, 11 that will become the sub-core shown in FIG. 4(a), respectively. Further, one ferrite block 11 is formed with a winding groove (not shown) and a joining groove (not shown) that are perpendicular to the regulation groove 12 .

Next, as shown in FIGS. 4(c) and 4(d), a metal magnetic film 13 serving as the main core is formed on the opposing surfaces of the ferrite blocks 11, 11 by, for example, sputtering. Then, a front gap portion 11a of the Ferrai I block 11 in which the winding groove 14 and the joining groove 15 are formed.
An oxide film 16 that will become a magnetic gap portion is formed on the metal magnetic film 13 .

After this, as shown in FIG.
A glass 17 is placed on the ferrite blocks 11, 11 is melted, and the ferrite blocks 11, 11 are joined together. Note that the winding groove 14 is formed with a winding hole into which a coil is wound.

Then, as shown by the broken line in FIG. 4(f), the integrated ferrite blocks 11, 11 are cut at a predetermined pitch along each regulation groove 12, and polished to form a medium contact surface. As a result, the magnetic head shown in FIG. 3 is obtained.

However, the above-described magnetic head has the following problems.

First, when a pair of subcores are joined by melting glass, the main cores of both subcores are joined, so peeling easily occurs between the subcore (ferrite) and the main core (metallic magnetic film). Furthermore, there is a problem that good characteristics of the magnetic head cannot be obtained because appropriate stress is applied to the sub-core.

Further, a pseudo gap is likely to occur between the sub-core and the main core, and in order to prevent this, it is necessary to lower the bonding temperature of the glass, so a low melting point glass is used. Therefore, there is a problem that the abrasion resistance of the medium contacting surface at the joint portion of the low melting point glass is low, and the wear resistance is severe over time.

(Problems to be Solved by the Invention) As described above, in the conventional magnetic head, it is difficult to obtain good characteristics of the magnetic head, and the wear resistance of the medium contact surface at the joint part of the low melting point glass is low. There is a problem with severe changes over time.

Therefore, it is possible to use high-melting point glass as the joint, but when the high-melting point glass is melted, the ferrite and metal magnetic film are exposed to high temperatures, causing the elemental exchange between the ferrite and the metal magnetic film to occur. Diffusion occurs;
There is a problem that magnetic properties are deteriorated.

The present invention is intended to solve the above-mentioned problems, and provides a magnetic head that can obtain good magnetic head characteristics and improve the wear resistance of the medium contact surface, and a method for manufacturing this magnetic head. It is intended to.

[Structure of the Invention (Means for Solving the Problems)] The magnetic head of the present invention is formed of a magnetic material, has regulating grooves formed on both sides of opposing surfaces, and has a winding groove perpendicular to the regulating grooves on at least one side. and a pair of sub-cores in which bonding grooves are formed, a pair of main cores each formed of a metal magnetic film on the opposing surfaces of these sub-cores, and a magnetic gap portion formed between the main cores;
a hard joint member formed in each regulation groove of the pair of sub-cores and exposed to the medium contact surface; a soft joint member formed in the winding groove and the joint groove of the pair of sub-cores to join the pair of sub-cores together; We are preparing for this.

Further, the method for manufacturing a magnetic head of the present invention includes a first step of mirror-finishing predetermined opposing surfaces of a pair of magnetic blocks and forming a plurality of regulating grooves at a predetermined pitch on each of the opposing surfaces; a second step of forming a hard bonding layer on the opposing surface of each of the magnetic blocks including the regulating grooves and lapping the surface to make it smooth; a third step of grinding the hard bonding layer to expose the opposing surface to form opposing surface exposing grooves, and forming a magnetic metal thin film on the entire surface of each of these magnetic blocks including the opposing surface exposing grooves. a fourth step, wrapping the magnetic metal thin film on the facing exposed groove of each of these magnetic blocks so that it is flush with the hard bonding layer and has a predetermined thickness; a fifth step of mirror-finishing the lapped surface; a sixth step of forming a non-magnetic film on the magnetic metal thin film of the one magnetic block; and a sixth step of forming a non-magnetic film on the magnetic metal thin film of the one magnetic block; The seventh step of forming orthogonal winding grooves and bonding grooves, and the opposing surfaces on which the magnetic metal thin film of each magnetic block obtained in the sixth step and the seventh step are formed, respectively. A pair of magnetic blocks is formed by placing a soft bonding member in contact with the regulating grooves so as to face each other, and disposing the soft bonding member completely over the winding groove and the joint, and melting the soft bonding member so that a cavity is formed in the winding groove. A magnetic head is manufactured through an eighth step of joining them together, and a ninth step of cutting the joined magnetic blocks at a predetermined pitch along the regulating grooves and forming a medium contact surface. It is characterized by

(Function) In the present invention, a magnetic metal thin film serving as the main core is formed on the surface exposed by grinding the hard bonding layer, and the sub-core is integrated with a soft bonding member made of low melting point glass at a low melting point. Therefore, the occurrence of pseudo gaps is effectively prevented, and a predetermined stress can be applied to the subcore by the hard bonding layer formed directly on the regulating groove of the subcore, thereby making it possible to obtain good magnetic head characteristics. can. In addition, since the hard bonding layer is exposed on the media contact surface that satisfies the ]0 regulation,
A magnetic head with improved wear resistance and less deterioration over time can be provided.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing a magnetic head according to an embodiment of the present invention.

In the figure, 21a and 21b indicate a pair of subcores made of ferrite, for example. Regulation grooves 22, 22 are formed on both sides of the opposing surfaces of the sub-cores 21a, 2lb, respectively, and these regulation grooves 22
A hard joint portion 23 made of high melting point glass is formed in the. Further, one sub-core 21a is formed with a winding groove 24 orthogonal to the above-mentioned regulation groove 22 and a joint 25.

In addition, the above-mentioned hard joint 2 of sub-core 2]a, 21b
3 is a rough surface, and the main core 26a is formed on this surface by a metal magnetic film such as sendust.
, 26b are formed.

Further, between the opposing surfaces of the main cores 26a and 26b, S
A magnetic gap portion 27 is formed of an oxide film such as i02.

Further, a soft bonding member 28 made of low melting point glass is arranged in a part of the winding groove 24 and the bonding groove 25 formed in the sub-core 21a, and these soft bonding members 28 are melted to form the sub-core 21. a, 2lb are joined together.

Note that S indicates a medium contacting surface, and the above-mentioned hard joining member 23 is exposed in the regulating groove 22 portion of this medium contacting surface S. Moreover, 29 is a winding hole in which a coil is wound.

Next, a method for manufacturing the magnetic head described above is shown in FIGS. 2(a) to 2(a).
This will be explained using (k). In addition, Fig. 2 (a) to (g)
1 shows one of a pair of ferrite blocks.

First, as shown in FIG. 2(a), a pair of mirror-finished ferrite blocks 31, 31 serving as sub-cores are provided with a plurality of regulating grooves 32 at a predetermined pitch, as shown in FIG. 2(b). is formed by, for example, a dicing machine.

Next, as shown in FIG. 2(C), high melting point glass is melted on the entire opposing surface of each ferrite block 31 to fill the regulation grooves 32, and the hard bonding layer 34 is formed so as to bulge from the opposing surface. form.

Thereafter, as shown in FIG. 2(d), the surface of the hard bonding layer 34 formed on each ferrite block 31 is lapped to form a flat surface.

Then, as shown in FIG. 2(e), the hard bonding layer 34 is ground so that the surface of the portion between the regulating grooves 22 of each ferrite block 31, 31 is exposed, and a groove 35 is formed in which the ferrite surface is exposed. Form.

Note that the surface of the groove 35 is a rough surface.

Next, as shown in FIG. 2(f), the hard bonding layer 34 of each ferrite block 31, 31 and the entire surface of the groove 35 are sputtered to form a sendust film 35, which is the main core.
form.

After this, as shown in FIG. 2(g), sender 1 and membrane 3
6 is the sender l on the groove 35 and the film 36 is the hard bonding layer 34
The block 37 shown in FIG. 2(h) is obtained by wrapping the block so that it is flush with the surface and having a predetermined thickness, and then mirror-finished.

Then, as shown in FIG. 2(i), one block 3
7, a winding groove 38 and a joining groove 39 which are perpendicular to the above-mentioned regulation groove 32 are formed, and a non-magnetic film serving as a magnetic gap is formed in the Freon 1 gap part 40.

Next, each block 37 shown in FIGS. 2(h) and (i)
, 37, as shown in FIG. 2(j), each block 37
The sendust films 36, 36 are butted together so as to correspond and overlap, and soft bonding members 41, 41 made of low melting point glass are inserted into the winding groove 38 and the bonding groove 39, and bonded by heating at a predetermined temperature. As a result, the joined integral block 42
is obtained. Thereafter, as shown in FIG. 2(k), the integral block 42 is cut at a predetermined pitch so that the abutting part (magnetic gap part) of the sendust film 36 is approximately at the center, and the medium contacting S The magnetic head shown in FIG. 1 can be obtained by performing metal processing to form the magnetic head.

[Effects of the Invention] As explained above, the magnetic head of the present invention and the method for manufacturing the magnetic head are such that the magnetic metal thin film serving as the main core is formed on the surface exposed by grinding the hard bonding layer, and has a low melting point. Since the sub-core is integrated with a soft bonding member made of glass at a low melting point, the occurrence of pseudo gaps is effectively prevented, and the hard bonding layer formed directly in the regulation groove of the sub-core applies a predetermined stress to the sub-core. As a result, good magnetic head characteristics can be obtained. Further, since the hard bonding layer is exposed on the medium contacting surface of the regulating groove, it is possible to provide a magnetic head with improved wear resistance and less change over time.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a magnetic head according to an embodiment of the present invention;
FIGS. 2(a) to (k) are diagrams for explaining the manufacturing method of the magnetic head shown in FIG. 1, FIG. 3 is a perspective view showing a conventional magnetic head, and FIGS. 4(a) to (f) 3 is a diagram for explaining a method of manufacturing the magnetic head of FIG. 3. FIG. 21a, 2lb-Sub core, 22, 3 2-... Regulation groove, 23... Hard joint, 24... Winding groove, 25...
・Joining groove, 26a, 26b...Main core, 27...
・Magnetic gap part, 28, 40... Soft joining member, 31
... Ferrite block, 34 ... Hard bonding layer, 3
5 grooves, 36... Sendust film. Applicant: Toshiba Corporation Toshiba Audio/Video Engineering Corporation

Claims (2)

[Claims] (1) A pair of sub-cores formed of a magnetic material, each having a regulating groove formed on both sides of opposing surfaces, and a winding groove and a joining groove perpendicular to the regulating groove formed on at least one of the sub-cores; A pair of main cores each formed of a metal magnetic film on its surface, a magnetic gap portion formed between the main cores, and a hard joint formed in each regulating groove of the pair of sub-cores and exposed to the medium contact surface. A magnetic head comprising: a member; and a soft joining member formed in the winding groove and joining groove of the pair of sub-cores and joining the pair of sub-cores together. (2) A first step of mirror-finishing predetermined opposing surfaces of a pair of magnetic blocks, and forming a plurality of regulating grooves at a predetermined pitch on each of the opposing surfaces; and each of the regulating grooves of each of these magnetic blocks. a second step of forming a hard bonding layer on the opposing surface including the grooves and lapping the surface to make it smooth; a third step of grinding the bonding layer to form opposing surface exposed grooves; a fourth step of forming a magnetic metal thin film on the entire surface of each of these magnetic blocks including the opposing surface exposed grooves; and each of these steps. A fifth step of wrapping the magnetic metal thin film on the facing exposed groove of the magnetic block so that it is flush with the hard bonding layer and having a predetermined thickness, and finishing the lapped surface with a mirror finish. a sixth step of forming a non-magnetic film on the magnetic metal thin film of the one magnetic block; and forming a winding groove and a bonding groove orthogonal to the regulation groove in the other magnetic block. a seventh step of forming, and bringing the opposite surfaces of each magnetic block obtained in the sixth step and the seventh step, on which the magnetic metal thin film is formed, into contact with each other so that the regulating grooves face each other. an eighth step of arranging a soft joining member in the winding groove and the joining groove and melting the soft joining member so as to form a cavity in the winding groove to join the pair of magnetic blocks together; A method for manufacturing a magnetic head, comprising: a ninth step of cutting the integrally joined magnetic block at a predetermined pitch along the regulating groove and forming a medium contact surface.