JPS61113109A - Production of magnetic head - Google Patents

Abstract

PURPOSE:To improve a life of the magnetic head itself by holding a desired width gap composed of high melting glass between a pair of magnetic cores and further, coupling strongly by a low melting point glass at both sides of the groove for winding. CONSTITUTION:In the butted surface of a pair of core blocks 21a and 21b, plural notch grooves 5 for regulating a track width are formed along the lengthwise direction angle part of the core block at the prescribed interval and a groove 8 for winding and a groove 6 for reinforcement are formed at one side core block 21a. After a low melting point glass rod 7 is placed at the notch groove 5, the groove 8 for winding and the groove 6 for reinforcement, thermal treatment is executed and the glass 7 is filled in the notch groove 5 the groove 8 for winding and the groove 6 for reinforcement. Next, the protruded glass 7 is removed, and further, a mirror surface-shaped glass layer is formed on the forming wall surface of the groove 8 for winding by the glass 7 in the groove 8 for winding. To respective protruded surfaces of both blocks 21a and 21b, a high melting point glass layer 4 is covered, and thereafter, both blocks 21a and 21b are protruded, the heating processing is executed by the melting temperature of the low melting point glass and the coupling body is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of manufacturing a magnetic head used particularly in a VTR or the like.

[Conventional technology]

Conventional magnetic heads used in high-performance audio, VTRs, etc. are made of a pair of rectangular parallelepiped core blocks made of ferrite or other ferromagnetic material, and a low-melting point adhesive is used to form the gap between the core blocks, which also serves as an adhesive between the core blocks. Crow e.g. 510
Inject and fill the space for gear lug formation by capillary phenomenon with galanu, which has added a PB component to 2, or heat and press the core block with glass foil interposed as a spacer on the same earthen floor,
Alternatively, after forming a glass thin film on the core block by sputtering etc., the glass layer is sandwiched and heat-pressed to join the core blocks, and then the core block is cut in the longitudinal direction at regular intervals. It is made by.

However, when low-melting glass is used for the gap, the gap width slightly fluctuates depending on the strength of the bond between the Core Pro and the adhesive, making it difficult to determine the gap width accurately, which improves the precision of the cap width. As a result, the characteristics of the magnetic head have deteriorated.

Therefore, a magnetic head as disclosed in Japanese Patent Laid-Open No. 57-58219 was developed. That is, as shown in FIG. 4, this magnetic head has two magnetic cores 31a of a predetermined shape.
A non-magnetic material with a relatively high softening point is placed across the gap 32 between the abutting surfaces of the magnetic cores 31a and 31b, and a non-magnetic material with a relatively low softening point is placed between the abutting surfaces of the magnetic cores 31a and 31b. It is glued with 33. 34 is a winding groove, and 35 is a coil wound around the magnetic core 31a through the winding groove 34.

[Problems with conventional technology]

However, with the conventional magnetic head shown in FIG. The coil 35 and magnetic core 3 with damaged coatings because no insulation treatment was applied to the forming surfaces.
1a electrically contact the corners of the winding groove 34, causing insulation failure and significantly shortening the life of the magnetic head itself.

The purpose of the present invention is to solve such problems and to provide gears with a desired width,
To provide a method for manufacturing a magnetic head in which the magnetic core and the coil are firmly coupled so that the magnetic core and the coil do not come into direct electrical contact even if the coating of the coil in the winding groove is damaged.

[Means for solving problems]

In order to solve the above problems, the present invention forms a winding groove in the longitudinal direction of at least one of the core blocks in the abutting surfaces of a pair of rectangular parallelepiped core blocks made of magnetic material, and A plurality of notched grooves are formed at predetermined intervals along the longitudinal direction in the abutting portion of each of the core blocks located on one side with respect to the winding groove, and further, a plurality of notched grooves are formed in the winding groove in at least one core block. On the other hand, a reinforcing groove is formed in the longitudinal direction of the core block on the opposite side to the notch groove forming side, #reinforcing groove,
After filling the winding groove and the plurality of notched grooves with low melting point glass, the low melting point glass portion in the winding groove is cut to form a thin low melting point glass layer on the groove forming surface. Then, a high melting point glass for forming gear horns is deposited on the abutting surface of at least one of the pair of core blocks by means such as vapor deposition or sputtering, and then the pair of core blocks are abutted to meet the melting temperature of the low melting point glass. The core block is integrated by heat treatment, and the integrated product is cut into a desired shape by cutting in the lateral direction of the core block at each of the notched grooves.

The material of the low melting point glass is not particularly limited as long as it has an insulating property and strengthens the bond between the pair of core blocks, and has a melting point lower than the high melting point glass forming the gap. For example, when 5i02 is used as the high melting point glass, SiO2 plus Pb is used as the low melting point glass.

Further, in the method of the present invention, in order to uniformly leave the low melting point glass formed as a thin layer in the winding groove on the surface where the winding groove is formed, the pair of core plates are integrated by low melting point glass welding. In this case, it is preferable to join the pair of core blocks while rotating them. [Embodiments of the Invention] Examples of the present invention will be described below with reference to the drawings.

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

la and lb are magnetic cores (hereinafter referred to as cores) that are roughly in the shape of an opening, and a hollow part is provided at the center of the core la and lb so that a closed magnetic path is formed in the core la and lb during recording and reproduction. A gap 3 is formed between the abutting surfaces of the cores la and lb. The gear 13 is made of a glass layer, and the cores la and lb are welded to the glass layer with glass 7 filled in the track width regulating notch 5 and reinforcing groove 6.

A thin layer 7a made of the same glass as the glass 7 filled in the notch groove 5 and reinforcing groove 6 is formed almost uniformly on the wall surface of the hollow part 2 in the cores la and lb.
A coil 9 is passed through the hollow portion 2 and wound around the core 1a on the side where the winding groove 8 is formed, with the glass layer 7a interposed therebetween.

2(a) to 2(j) are process diagrams showing the manufacturing process of the magnetic head 1 of the present invention, in which 21 shown in FIG. 2(a)
A521b is a pair of core blocks made by cutting a magnetic material such as ferrite into a desired rectangular parallelepiped shape. At the abutting surfaces of the pair of core blocks 21a and 21b,
As shown in FIG. 2(b), a plurality of notch grooves 5 for regulating track width are formed along the longitudinal corners of the core block at predetermined intervals, and a winding groove is formed in one core block 21a. 8 and reinforcing grooves 6 are formed. In the detailed description of the present invention, the winding @8 and the reinforcing groove 6 were formed on one block 21a, but they were formed on both blocks 21. a, 2
1b.

Further, the winding groove 8 and the reinforcing groove 6 may be formed in separate blocks 21a and 21b, respectively.

Then, as shown in FIG. 2 (C1), a low melting point glass rod 7 containing, for example, an S'Ozi copper acid component is placed in the notch groove 5, the winding groove 8, and the reinforcing groove 6, and then the glass Bar 7
The glass 7 is heat-treated to fill the notch groove 5, the winding groove 8, and the reinforcing groove 6 so as to protrude outward as shown in FIG. 2 (CD).

Next, as shown in FIG. For example, by cutting using a forming grindstone or the like, a mirror-like glass layer 7a with a thickness of about 30 μm is formed on the forming wall of #I #8 for winding as shown in FIGS. 2(f) and 2(f). do.

Then, a high melting point glass such as 5i02 is deposited on the abutting surfaces of the two blocks 21a and 21b by vapor deposition, sputtering, or an equivalent means so that the thickness is equal to the desired gear width. figure(
g) After cutting out the high melting point glass layer 4 indicated by the hatched area, both blocks 21a and 21b are cut out as shown in FIG. 2(h).
match. Then, heat treatment is performed at the melting temperature of the low melting point glass, and both blocks 21a and 21b are fused together using the filling glass 7 to form a combined body. In addition, where high melting point glass and low melting point glass touch,
High melting point glass is assimilated to low melting point glass.

Next, in Fig. 2(i), the part indicated by the dotted chain line, that is,
The combined body is sequentially cut to a predetermined width at each of the notched grooves 5, and the unnecessary lower portion is cut away from the reinforcement #I#6 to form a predetermined shape as shown in FIG. 2(j). A magnetic head 1 having cores 1a and 1b is obtained.

In the magnetic head l obtained in this way, the tape sliding surface is polished into a circular arc shape in the subsequent process, and the coil 9 is wound in the hollow part 2 formed by the winding groove 8. It is passed around. Incidentally, FIG. 3 shows a cross section of a main part of the magnetic head 1 manufactured by the manufacturing method of the present invention.

〔Effect of the invention〕

According to the method of the present invention as explained above, a gap of a desired width made of high melting point glass is provided between a pair of magnetic cores,
Furthermore, the magnetic head is firmly bonded by low-melting glass portions located on both sides of the winding groove, and a thin insulating glass layer is formed on the wall surface forming the winding groove for forming a closed magnetic path of the magnetic head. It can be easily manufactured. Therefore, in the magnetic head manufactured by the method of the present invention, even if the coating of the coil that is wound around the magnetic core through the winding groove is damaged at the corner of the surface where the winding groove is formed, the insulation will not be damaged. Because the magnetic core itself and the coil are electrically insulated by the glass layer,
This has the significant advantage of improving the lifespan of the magnetic head itself.

[Brief explanation of drawings]

1 to 3 are diagrams for explaining one embodiment of the method of the present invention. FIG. 1 is a perspective view showing a magnetic head obtained by the method of the present invention, and FIGS. FIG. 3 is a cross-sectional view of a main part of a magnetic head, and FIG. 4 is a perspective view of a conventional magnetic head. 1... Magnetic head la, lb... Core block 3... Gear knob 4 Glass layer 5 forming a gap, notch groove 6... Reinforcing groove 7 Low melting point glass 7a Low melting point glass layer 8 Coil winding Groove 9 Coil Patent Applicant Alps Electric Co., Ltd. Engraving of drawings (no changes in content) Fig. 2 (o) 1b Fig. 2 (d) Fig. 21''1 (e) (f) Fig. 2 1b 2 Figure (+) (j) Mine 3 Figure 4 Figure 4 Figure 4 Figure No. 59-215986 Title of the invention Method for manufacturing a magnetic head 3 Relationship with the amendment person case Patent applicant address Yukitani, Ota-ku, Tokyo 145 Otsukacho 1-7 Name A
O9 Alps Electric Co., Ltd. January 9, 1985 (shipment date January 29, 1985) 5. Subject to amendment

Claims (2)

[Claims] (1) A winding groove is formed in the longitudinal direction of at least one of the core blocks on the abutting surfaces of a pair of rectangular parallelepiped core blocks made of a magnetic material, and a winding groove is formed on one side of the winding groove. A plurality of notch grooves are formed at predetermined intervals along the longitudinal direction of each abutting portion of the core block, and further, in at least one core block, a portion of at least one of the core blocks is opposite to the side where the notch grooves are formed with respect to the winding groove. A reinforcing groove is formed in the longitudinal direction of the core block, and after filling the reinforcing groove, the winding groove, and the plurality of notch grooves with low melting point glass, the low melting point glass in the winding groove is filled. Cutting the glass part to form a thin low melting point glass layer on the groove forming surface, and then vapor depositing or sputtering high melting point glass for gap formation on the abutting surface of at least one core block of the pair of core blocks. After that, the pair of core blocks are butted together and integrated by heat treatment at the melting temperature of low melting point glass.
A method of manufacturing a magnetic head, comprising cutting the integrated product in the width direction of the core block at each of the notch grooves to form a desired shape. (2) When the pair of core blocks are integrated by welding low melting point glass, the pair of core blocks are joined while being rotated.
A method for manufacturing a magnetic head as described in .