JPS58169318A - Magnetic head and its manufacture - Google Patents

Abstract

PURPOSE:To raise accuracy of gap size, especially, gap width, and to obtain an excellent magnetic head for high density recording, by constituting a gap spacer material of a magnetic head of an adhesive for joining each core half-body, and a nonmagnetic material which scarcely generates a mutual diffusing phenomenon. CONSTITUTION:In a rectangular parallelepiped block 1 of Mn-Zn ferrite, etc., a groove 2, a groove 3 which becomes a winding window being parallel to said groove, and a recessed part 4 being orthogonal to the grooves 2, 3 are formed on the corner of the face of a tape running face side, and a thin film layer 8 having thickness (g), which becomes gap width of a magnetic head is formed between said recessed parts 4 by a nonmagnetic material having a comparatively high melting point and high hardness, such as a cermet of SiO-Cr, etc., Cr, SiC, etc., and a low softening point glass layer 9 whose thickness is below (g) is formed against the groove 3 on the face of the substrate 1 of the opposite side to the recessed part 4. This block 1 is butted to the magnetic block rectangular parallelopiped 5 provided with a groove 6 and a recessed part 7 so that the recessed part 4 and the recessed part 7 coincide with each other exactly, a glass rod 10 having low softening point is inserted into the grooves 2, 6, is pressed and heated, and the block 1 and 5 are joined. Subsequently, it is cut to each head 12 and a head of high accuracy is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic head and a method for manufacturing the same, and relates to a magnetic head in which core half-holes are bonded to each other with an adhesive, in which a mutual diffusion phenomenon occurs when the gap portion of the magnetic head is bonded to the adhesive between the core half-holes. By using a non-magnetic material that is difficult to cause, the accuracy of the gap dimensions, especially the gap width, is extremely high, and the magnetic properties of the magnetic helad core are not deteriorated, and the manufacturing yield is significantly improved. The purpose of the present invention is to provide a magnetic head and a method for manufacturing the same.

Conventionally, magnetic heads for high-density recording video tape recorders, for example, have used single-crystal ferrite or polycrystalline ferrite as the magnetic material, used quartz glass with a high softening point to define the gap width for the gap spacer, and placed the cores half-half apart. A thin film of low-melting glass is formed in the rear gap, and the core halves are joined together by heat and pressure bonding. In order to narrow the track, the recesses that define the track width are melted and filled with glass. For this reason, when the concave part is filled with glass and the rear part made of low-melting point glass is heated to melt and bond, a phenomenon occurs in which the glass filled in the convex part and the quartz glass used as a gap spacer mutually diffuse. As a result, the gap spacer changes into a mixed glass with a low melting point different from the original silica glass, and the gap width varies slightly depending on the degree of compression between the half-core cores, making it impossible to determine the gap width accurately. It is difficult to improve the accuracy of the gap width, and the characteristics of the magnetic head deteriorate. Furthermore, since it is difficult to produce a material with a uniform gap width, the manufacturing yield is also poor.

Also 1. A mutual diffusion phenomenon occurs between the core semicircular material such as ferrite and the mixed glass of the gap spacer during heat and pressure bonding.
The magnetic properties of ferrite and the like near the gap are degraded.

The present invention eliminates the above-mentioned drawbacks, and examples thereof will be described below.

1 to 6 are explanatory diagrams of the manufacturing process of the magnetic head according to the present invention.

First, as shown in FIG.
After mirror-polishing the upper surface of this rectangular parallelepiped block 1, a groove 2 serving as a notch is formed along the longitudinal direction at the corner of this mirror-polished surface and the surface on the tape running surface side.
A groove 3, which will serve as a winding window, is formed by grinding substantially parallel to the groove 3. Further, a plurality of recesses 4 are formed at regular intervals in a direction orthogonal to the grooves 2 and 3 of the rectangular parallelepiped block 1 so as to connect to the grooves 2 and 3 using a dicing saw or the like using a thin diamond blade. Note that the shape of this recess 4 is such that its depth is deep at the end of the rectangular parallelepiped block, that is, the part on the groove 2 side.
It is formed in a tapered shape so that the portion on the groove 3 side is shallower, and its width is approximately constant.

Further, as shown in FIG. 2, a rectangular parallelepiped block 5 having the same shape as the rectangular parallelepiped block 1 was formed by cutting and grinding a high permeability magnetic material such as Mn-Zn ferrite, and the upper surface of this rectangular parallelepiped block 5 was mirror-polished. Back, groove 2 of rectangular parallelepiped block 1
A groove 6 similar to the above is formed, and a recess 7 similar to the recess 4 of the rectangular parallelepiped block 1 is formed.

Next, as shown in FIG. 3, a gap spacer such as a cermet such as 8i0-Or, chromium metal, 8i0
etc. (ideal compounds, mixed oxide magnesia, etc.)
A thin film layer 8 having a thickness g corresponding to the gap width of the magnetic head is formed by sputtering or the like using a non-magnetic material with a relatively high melting point and high hardness other than glass such as alumina or titania.

Further, on the flat surface of the upper surface of the rectangular parallelepiped block 1, which is opposite to the flat surface on which the thin film layer 8 is formed with the groove 3 as a boundary, a glass thin film layer 9 having a thickness of g or less and having a low softening point is applied by slatting, etc. This glass thin film layer 9 is formed by a rectangular parallelepiped block 1.
It also has the role of an adhesive for bonding the rectangular parallelepiped block 5 and the rectangular parallelepiped block 5 together.

Then, the rectangular parallelepiped blocks 1 and 5 configured as shown in FIG. 2 and FIG. As shown in FIG.
A rod-shaped glass 10 having a relatively low softening point, which is about .degree.

Then, the rod-shaped glass 10 fills the groove formed by the grooves 2 and 6, and also fills the gap formed by the recesses 4 and 7, and this softened and filled glass fills the rectangular parallelepiped block 1. and 5 are bonded together, and the rectangular parallelepiped blocks 1 and 5 are also bonded together by the softened glass thin film layer 9.

When the rectangular parallelepiped blocks 1 and 5 are bonded together under heat and pressure, the rod-shaped glass 10 softens and flows into the gap formed by the recesses 4 and 7, and this softened glass with a relatively low softening point forms a thin film. The layer 8 is not attacked, and there is no interdiffusion phenomenon between the thin film layer 8 and the glass.1For example, the thickness of the thin film layer 8 changes and the gap width deviates from the thickness g when the thin film layer was formed. The gap dimension can be formed with high precision without causing any adverse effects such as. or,
Since a non-vitreous high melting point non-magnetic material is used as the gap spacer material at the joint surface between the rectangular parallelepiped block and the thin film layer, the magnetic material near the gap will not be attacked and the magnetic properties will not deteriorate. .

Next, rectangular parallelepiped blocks 1 and 5 joined by glass
As shown in FIG. 5, the composite block 11 is cut along an imaginary plane shown by a dashed line and a dashed double dotted line.

Thereafter, a predetermined cutting and polishing process is performed to form the magnetic head 12 as shown in FIG. 13.14 in Figure 6
is a half core formed by rectangular parallelepiped blocks 1 and 5, 1
5 is a winding window formed from the groove 3, and 116 is a gap spacer formed from the thin film layer 8.

In the magnetic head configured as above, the gap portion is
The part that determines the gap width is made of a non-vitreous non-magnetic material with a relatively high softening point, and the part that does not contribute to determining the gap width is made of a non-vitreous non-magnetic material with a relatively high softening point. Since the magnetic herad core halves are bonded together using a glass material with a low softening point in the area other than the gap spacer sandwiching surface, the gap width is predetermined when the core halves are bonded together. Since no fluctuations occur, it is possible to configure the gap width dimension extremely accurately, and measurement of the gap dimension is easy.Also, there is no mutual diffusion phenomenon at the sandwiching surface between the gap spacer and the core half-hole during heat bonding, and the gap width is The magnetic properties of the magnetic material near the spacer joint surface are not degraded, and the magnetic head has excellent high frequency properties, for example.

In addition, since mixing and mutual diffusion does not occur between the gap spacer material and the glass filled in the recesses formed on both sides of the gap spacer holding portion of the core half-closed, the composition of the gap spacer material does not change. For example, a gap with an extremely high precision gap width can be constructed.

Furthermore, even if the core half-holes are not bonded to each other on the gap spacer clamping surface, the recesses formed on both sides of the gap spacer are filled with low softening point glass and are firmly bonded, so during cutting and polishing. The production yield has been significantly improved, and the abrasion resistance during tape running is also excellent.

Similarly, in the above embodiment, the thin film layer 8 was formed only on the rectangular parallelepiped block 1, but it may also be formed on the rectangular parallelepiped block 5, and in such a case, the thin film layer 8 was formed on each rectangular parallelepiped block. The gap width may be the sum of the thicknesses of the thin film layers, and the same applies to the glass thin film layers.

As described above, in the magnetic head according to the present invention, the gap spacer material of the magnetic head is made of a non-magnetic material that does not easily cause the mutual diffusion phenomenon with the adhesive that joins the core halves. As a result, the dimensional accuracy of the gap dimension, especially the gap width, is extremely high, and there is no deterioration in the magnetic properties of the magnetic material core, for example, it is excellent in high frequency properties, etc., and the magnetic material according to the present invention The head manufacturing method includes forming grooves to serve as winding windows at a predetermined position in at least one of the two substantially rectangular blocks made of magnetic material, and forming grooves at predetermined intervals in a direction substantially orthogonal to the grooves. A plurality of substantially concave portions are formed in two substantially rectangular parallelepiped blocks, and at least one of the substantially rectangular parallelepiped blocks is provided at a predetermined position, which is a gap formation position, with a non-stick material that is unlikely to cause mutual diffusion with the adhesive when the substantially rectangular parallelepiped blocks are bonded together. After forming a film of a predetermined thickness with a magnetic material, the abutting surfaces of these approximately rectangular parallelepiped blocks are butted against each other, and then an adhesive is placed in the gap between the abutting surfaces of the approximately rectangular parallelepiped blocks to join the approximately rectangular parallelepiped blocks together. After that, the joined substantially rectangular parallelepiped blocks are cut into a predetermined shape along a predetermined virtual plane passing through the substantially concave portion position, so that a magnetic head with a gap of highly accurate dimensions can be manufactured at a high manufacturing yield and at low cost. When the gap is formed, magnetic properties of the magnetic material near the gap are not deteriorated, and magnetic properties excellent in, for example, high frequency properties can be obtained.

It also has the advantage of being able to provide products with excellent wear resistance.

[Brief explanation of the drawing]

1 to 6 are explanatory diagrams of the manufacturing process of the magnetic head according to the present invention. 1.5... Rectangular parallelepiped block, 2.3.6... Groove, 4
．． 7... Concave portion, 8... Thin film layer, 9... Glass thin film layer, 10... Rod-shaped glass, 11... Composite block,
12...Magnetic head, 13.14...Core half-off, 1
6...Gap spacer. Patent applicant: Japan Victor Co., Ltd. Agent: Katsu Uko Intrusion. Deception. Talented I Ll! Sai 3 I Otsu Ichi sai! 5 figure 1'2 zo Σ year 6 year 1

Claims (1)

[Claims] ■ In a magnetic head in which core halves are bonded to each other with an adhesive, the gap spacer material of the magnetic head is made of an adhesive that joins the core halves and a non-magnetic material that is unlikely to cause mutual diffusion. A magnetic head characterized by: ■ A groove serving as a winding window is provided at a predetermined position in at least one of the two substantially rectangular blocks made of magnetic material, and a plurality of grooves are provided at predetermined intervals in a direction substantially orthogonal to the groove. Concave portions are formed in two substantially rectangular parallelepiped blocks, and at least one of the substantially rectangular parallelepiped blocks is formed at a predetermined position where a gap is formed using a non-magnetic material that is unlikely to cause mutual diffusion with adhesive when the substantially rectangular parallelepiped blocks are bonded together. After forming a thick film, the abutting surfaces of these substantially rectangular parallelepiped blocks are faced and butted together, and then an adhesive is placed in the gap between the abutting surfaces of the substantially rectangular parallelepiped blocks to join the substantially rectangular parallelepiped blocks. 1. A method of manufacturing a magnetic head, which comprises cutting a substantially rectangular parallelepiped block joined together along a predetermined imaginary plane passing substantially through a recessed portion position to form a predetermined shape.