JPS63183603A - Magnetic head core - Google Patents

Abstract

PURPOSE:To raise the strength by a simple work method, by spattering in advance SiO2 or glass to a magnetic head butting surface, and thereafter, sticking a core butting surface by a thin resin layer. CONSTITUTION:A block of a magnetic head ferrite core is formed to a C shape and an In shape by machining, by using a ferrite material of high density made by a high temperature and uniform pressure homogeneous press. One 11 of butting surfaces 11, 12 is a butting surface of an air-gap part. On this butting surface 11, an air-gap is made by making a film 2 by SiO2 or glass, etc., by spattering or vapor-deposition, and thereafter, by making a thin resin layer film 3, each film 2 of SiO2 or glass, or the film 2 and ferrite are stuck and reinforced, by which an air-gap having an equal strength to the case of glass welding is formed. As for thickness of the resin for this adhesion, a thin layer of <=0.3mum is formed, and as for the resin 3, a two-liquid and temperature-rise hardening type resin is used.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for forming a cavity in a head core for an FDD.

In general, to form the gap in the part of a magnetic head that contacts and slides on the magnetic recording medium, a method that relies on fusion using glass is generally adopted, and a glass pouring method is used at a temperature above the melting point. Or, there is glass or 5i on the magnetic head mating surface.
A method is used in which n2 is formed by sputtering, raised to a temperature above the melting point, and reinforced and fused with glass. For this reason, a high-temperature furnace was required to form the voids, and large-scale equipment was required for the head core bonding process.

According to the present invention, the S i 02
Alternatively, after sputtering glass, the core abutting surfaces are bonded with a thin resin layer to create a core abutting surface with the same strength as glass fusion, and the method of the present invention requires only small-scale equipment. The work method is simple, for example, when using a method such as glass fusion, M n
-Z When n-based ferrite is used as the material, a glass fusing device using a reducing atmosphere such as N2 gas is required to prevent oxidation, but the method of the present invention does not require such a device. has the advantages of

As described above, an object of the present invention is to provide a method for forming a gap in a mating surface of a magnetic head such as a head core for an FDD at low cost.

Next, detailed explanatory diagram of the present invention, Figure 1 shows a block of a magnetic head ferrite core.The ferrite core for a floppy disk uses high-density ferrite material made by high-temperature and isopressure homogeneous pressing.
Manufactured by machining into the shapes shown in a) and (b). 11 and 12 are abutting surfaces, and 11 is an abutting surface of the gap.
The ferrite block shown in Fig. 1(a) is manufactured by forming a film of Si02 or glass on the head abutting surface 11 by sputtering or vapor deposition, creating voids, and then forming a thin resin layer on the abutting surface. Or, by adhering and reinforcing glass films or films and ferrite, it forms voids with the same strength as glass fusion, and the thickness of the resin to be bonded is as thin as 0.3μ or less. It is characterized by having layers.

The resin used was a 21α temperature-curable resin, and in the examples of the present invention, an epoxy resin was used, and the adhesive was maintained at a temperature of 150° C. for 4 hours.

Figure 2(c) shows the shape of the ferrite block after resin bonding. The ferrite block bonded with 1M fat is shown in Figure-
The length of the butting part of b in 2(b) is approximately 0.3m/*
After polishing until it becomes 0.5 m/m thick, it is cut into chips.

Table 1 shows the resin adhesive layer of the magnetic head abutting part processed with resin adhesive according to the present invention, which was cut at the A-A section in Figure 2(c) and polished to a mirror surface. This is the value measured when expanded to .

The thickness of the resin adhesive layer was 0.087μ on average and 0.28μ at the maximum. Also, 0 and 5 made in the same process
The chips cut to m/■ thickness were heated to 60°C and humidity 95R.
After carrying out a 72-hour moisture resistance test with H, using a simple strength tester with three-point support using shear load as shown in Figure 13, we tested the head strength test using the conventional glass fusion method and the chip shear test using the process of the present invention. The strength of the core adhesive surface under load was tested.

The results are shown in Table 2, and in terms of the average value excluding cores with material failure that broke from the core portion, the breaking strength of the resin-adhesive head core was greater than that of the glass-fused core.

In addition, the dispersion value is almost the same as that of the glass-fused core, and the properties are equivalent to that of the glass-fused Herad core.

After bonding with resin, the head core is cut into chips and polished on both sides to a thickness of 200 μm. After combining with other head parts, the core mating surface is polished again to a length of about 100 to 30 μm for practical use.

As described above, as in the present invention, the gap length of the magnetic head core is made of SiO+ or glass, and the mutual adhesion of the cores is molded with a thin resin film, which is not used in the conventional Herad core gap molding method. There is no difference in strength from the conventional glass fusing method, and the present invention can be provided at a lower cost than head cores using conventional methods. In addition, although this embodiment describes a hard disk core for FDD, it is applicable to audio, VTR, and hard disk drives that use ferrite for the head core and conventionally use a glass fusion method to form a gap in the head mating joint. The gap forming method of the present invention can be applied to a gap forming method for a head for use in a vehicle.

[Brief explanation of the drawing]

Figure 1 shows a ferrite block for forming Fii Radcore voids. (a) is a C-shaped core, (b) is an I-shaped core. FIG. 2 is a cross-sectional view of a ferrite block for forming a magnetic herad core gap. (a) is only the material, (b) is SiO2
Or glass is sputtered or vapor-deposited, (C) is resin-bonded. Figure 3 is a load shear force tester for the butt-bonded part of the magnetic herad chip. 11.12.13...Mating surface, 2...510
2. Glass adhesive film, 3... Resin adhesive film, 4... Head chip, 5... Tension gauge, 6... Knives included. Patent applicant Tohoku Metal Industry Co., Ltd. fG) (b)

Claims (1)

[Claims] In a method for forming a head gap in a head using a ferrite core such as an FDD head core, S is applied to the head core mating surface of the gap forming area by sputtering or vapor deposition.
A magnetic head core in which voids are formed by attaching a film of iO_2 or glass, and bonding and reinforcing the films or the film and ferrite with a two-component thermosetting resin having a thickness of 0.3μ or less.