JPS63222310A - Production of magnetic head core - Google Patents

Abstract

PURPOSE:To facilitate forming a core and prevent destruction of core materials due to a film stress by providing narrow grooves between plural small grooves for thin film to form track parts and eliminating every other track part after sticking a thin film. CONSTITUTION:Narrow grooves 20 are provided between plural small groove parts 13 for thin film sticking on abutting faces of a pair of half core blocks HB consisting of an oxide magnetic body to form track parts 21. After a metallic magnetic thin film 14 is stuck to small groove parts 13, every other track part 21 is eliminated, and a head core is finished through prescribed processes. Since track parts 21 are formed on core blocks HB consisting of a single material in this manner, working is facilitated. Destruction of the core material due to film stress is prevented because the extent of sticking of the thin film 14 to wall surfaces 20a of track parts 21 is minimized.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a magnetic device in which a metal magnetic thin film is attached to the abutting surfaces of a pair of half cores made of an oxide magnetic material, and a magnetic gear shive is formed between the metal magnetic thin films. Regarding the head core,
In particular, the present invention relates to a method of manufacturing a magnetic head core of a type in which track grooves regulating track width are formed perpendicular to a magnetic gap.

"Prior Art and its Problems" Conventionally, a magnetic head core in which a track groove for regulating the track width is orthogonal to a magnetic gap has a configuration schematically shown in FIG. 3. That is, small grooves 13 for thin film adhesion are formed in each of the abutting surfaces of the pair of half cores 11 made of oxide magnetic material such as ferrite, facing each other along the magnetic gap 12 to be formed. A metal magnetic thin film 14 such as sendust is attached to the small groove 13 by a thin film attachment method such as sputtering or vapor deposition. A magnetic gap 12 is formed between the end faces of this metal magnetic thin film 14. A pair of track grooves 15 orthogonal to the magnetic gap 12 are formed on both sides of the magnetic gap 12, and the track width of the track portion 17 is regulated by the track grooves. The space of this track groove 15 is filled with a non-magnetic oxide bonding material (hereinafter referred to as glass) 16 such as glass, and the pair of half cores 11 are bonded and fixed. Note that 18 is a coil winding hole.

In this magnetic head core, the thin film adhesion small groove 13 to which the metal magnetic thin film 14 is attached is made uneven so as not to be parallel to the magnetic gap 12.
The track groove 15 can be prevented from becoming a pseudo gap with respect to the original magnetic gap 12, and the track groove 15 is formed perpendicular to the magnetic gap 12, so that the magnetic gap 1
2 are formed between the metal magnetic thin sheets @14 that face each other exactly, so that it is easy to achieve track shift width accuracy, and there is an advantage that a particularly wide track width can be easily formed.

By the way, in the manufacturing process of this magnetic head core, the metal magnetic thin film 11114 forming the magnetic gap 12 is deposited covering the thin film adhesion small groove 13 during the formation process of the thin film adhesion small groove 13. 1114
The track groove 1 is formed by processing the half core 11 with the
5, in the process of forming the track groove 15, the half core 1 is formed from above the metal magnetic thin s14.
It is necessary to process two materials at the same time. However, due to the difference in thermal expansion coefficient between the material of the half core 11 and the metal magnetic thin film 14, when the track grooves 15 are formed simultaneously, the film stress of the metal magnetic thin film 1114 acts,
Half core whose material is weaker than metal magnetic thin 1114] 1
Breakage is likely to occur in the material.

Particularly, when the width of the track portion 17 created by the formation of the track groove 15 is narrowed to correspond to a narrow track, destruction of the track portion 17 is unavoidable in the above-mentioned simultaneous machining.

OBJECTS OF THE INVENTION An object of the present invention is to provide a method for manufacturing a magnetic head core of the above type in which track portions are less likely to be destroyed due to film stress in a metal magnetic thin film.

"Summary of the Invention" The present invention forms a plurality of small grooves for thin film attachment at regular narrow intervals on the abutting surfaces of a pair of half core blocks made of oxide magnetic material, and between each of the small grooves, A narrow groove is formed to minimize the wall material S of the metal magnetic thin film to form a track portion, a metal magnetic thin film is attached to the small groove portion, and then one track portion is formed. It is characterized in that it is removed at intervals and the removed portions are used as track grooves. After that, a series of machining and bonding processes are performed to complete the magnetic head core, and the track portions are formed using half core blocks made of a single material, making the machining process easier. Since the adhesion of the metal magnetic thin film to the wall surface of this track part is minimized, the film stress of the metal magnetic thin film on the track part in this part is almost eliminated, making it extremely unlikely that the track part will break. It is possible to manufacture fewer magnetic head cores.

Embodiments of the Invention FIGS. 2(a) to 2(f) show an example of a method for manufacturing a magnetic head core according to the present invention, and will be described below in the order of manufacturing steps.

First, small grooves 13 for thin film adhesion are formed at predetermined narrow intervals on the abutting surfaces of the half core blocks Ha (Fig. 2(a)).
), this interval corresponds to the groove width W of the narrow groove 20 in the next step.

Next, a narrow groove 20 is formed in the shadow of each small groove 13 for attaching a thin film (FIG. 2(b)). In this case, the wall surface 20a is formed perpendicularly to the abutting surface of the half core block H8. magnetic thin 1114
The film thickness is set to a minimum. The groove width W varies depending on the method and conditions for thin film attachment, but is set to 20 μm or more so that the film stress of the metal magnetic thin film 14 does not affect the material of the half core block He.
This narrow groove 20 is preferably set to 0.1 mm.
Due to the formation of the track portion 21 between the narrow grooves 20
occurs.

In the next step, a metal magnetic thin film 1114 is deposited on the small groove 13 for thin film deposition by a thin film deposition method such as sputtering (FIG. 2(C)). This is performed after forming the track portion 21 by processing the narrow groove 20. Therefore, as in the conventional method, the metal magnetic thin film 14 and the half core block H having different coefficients of thermal expansion are
There is no need to simultaneously process ferrite, etc., which is the material of e, making the processing work easier. In this case, metal magnetic thin s1
The metal magnetic thin film 14 is also attached to the narrow groove 2o, but the thickness of the metal magnetic thin film 14 attached to the wall surface 20a is regulated to be sufficiently thin by the groove width W. Therefore, the film stress of the metal magnetic thin film 14 hardly acts on this portion, and the influence on the track portion 21 having a different coefficient of thermal expansion from this portion is suppressed, making it difficult for the track 21 to be destroyed due to the film stress.

After depositing the metal magnetic thin film 14, as shown in FIG. 2(d).
As shown by imaginary lines in Fig. 2, every other track portion 21 is ground and removed to form a track groove 15 (see Fig. 2(d)).
)) This grinding every other track is performed to maintain a constant distance between the remaining adjacent track portions 21.

Next, the track grooves 15 are filled with glass 16 to cover the metal magnetic thin film 14 on the small grooves 13 for thin film adhesion, and the abutting surfaces of the half core block H8 are polished (FIG. 2(e)).
), the metal magnetic Wil 14 adhering to the small groove 13 for thin film adhesion is now exposed on the abutting surface.

The pair of half core blocks H8 that have been processed as described above are brought together with the end faces of the metal magnetic thin film 14 interposed on their surfaces, and the glass 16
is heated to a temperature at which it melts and softens and joins the two (second
(f)), the magnetic head core shown in FIG. 1 is obtained by cutting as shown by cutting line A-8. The obtained magnetic head core has ! of the track portion 21! Although the thin metal magnetic thin film 14a is also attached to the surface 20a, the film stress of the metal magnetic thin film 1114a having such a thickness causes the track portion 21 to
will not destroy the material.

"Effects of the Invention" As explained above, according to the method for manufacturing a magnetic head core of the present invention, on the abutting surfaces of half core blocks,
After forming a plurality of small grooves for thin film adhesion at regular narrow intervals and forming a narrow groove between each of the small grooves to minimize the adhesion of the metal magnetic thin film to the wall surface to create a track portion. ,
A metal magnetic thin film is attached to the small groove portion, and the edges and the track portion are removed every other time, and the removed portions are used as track grooves, and then a series of processing is performed, so that the metal magnetic thin film and the half core block are Even if there is a difference in thermal expansion coefficient between the material and the material, it is possible to easily form a track section that accommodates a narrow track, and the thickness of the metal magnetic thin film that adheres to the wall surface of the track section can be kept to a minimum. Therefore, almost no film stress acts on the metal magnetic thin film in this portion, and material damage in the track portion is extremely small.

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view of a magnetic head core manufactured by the method of the present invention, FIG. FIG. 11-- Half core, 12... Magnetic gap, 13
...Small groove for thin film attachment, 14...Metal magnetic thin film, 15
...Track groove, 16-...Glass, 20-...Narrow groove, 2゜a...Wall surface, 21...Track part, H8...
・Half core block. Patent applicant Alps Electric Co., Ltd. Agent
Kunio Miura Shigeru Matsui (a) (b) Figure 2 (C) (d) Figure 2

Claims (2)

[Claims] (1) A small groove forming process in which a plurality of small grooves for attaching thin films are formed at regular narrow intervals on the abutting surfaces of a pair of half core blocks made of oxide magnetic material: between each of these small grooves, metal magnetic A narrow groove forming step in which a narrow groove is formed to minimize the adhesion of the thin film to the wall surface and track portions are created. A thin film adhesion step in which a metal magnetic thin film is adhered to the small groove portion. Step of forming a track groove in which the removed portion is used as a track groove: Step of filling the track groove with a non-magnetic oxide bonding material to cover the metal magnetic thin film on the small groove portion: Polishing the bonding material. A polishing process in which the metal magnetic thin film on the small groove is exposed: A bonding process in which a pair of half core blocks that have undergone the above processing are brought together at their abutting surfaces, and the end faces of the metal magnetic thin films are brought together and heated and bonded. Step: A method for manufacturing a magnetic head core, comprising: and a cutting step of cutting out the joined half core blocks at predetermined intervals. (2) The method for manufacturing a magnetic head core according to claim 1, wherein the narrow groove has a groove width of 20 μm to 0.1 mm.