JPS6313107A - Magnetic head - Google Patents

Abstract

PURPOSE:To obtain a magnetic head which can carry out satisfactory recoding and reproduction for the magnetic recording medium of a high coercive force and can improve the accuracy of a track width, etc., by extending a magnetic metallic film on the medium sliding surface of a magnetic head with a constant width and arranging an oxide magnetic body at one side of the metallic film. CONSTITUTION:A magnetic head is composed of ferrite blocks 21a and 21b as an oxide magnetic material, non-magnetic materials 22a, 22b, 23a and 23b such as high melting point glass, a magnetic gap 24, Sendust film 25a and 25b as a magnetic metallic film and a winding window 26. The Sendust films 25a and 25b are extended with the constant width in a medium sliding surface, and in a track width formed by the head, the border of the ferrite blocks 21a and 21b and the Sendust films 25a and 25b does not exit. Consequently, the border is not operated as a pseudo gap.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a magnetic head, and more particularly to a magnetic head formed by butting together a pair of core halves each including an oxide magnetic block and a magnetic metal film formed on the block. Regarding.

<Conventional technology> In recent years, with the development of magnetic recording technology, high-density magnetic recording has progressed, and for example, as a head for a video tape recorder (VTR), it is possible to record and play back on magnetic tape with high magnetic flux density and high coercive force. There is a demand for a magnetic head capable of narrowing the track.

In order to meet the above requirements, a magnetic head having a structure as shown in FIG. 7 has been proposed and put into practice. In Figure 7, la,
lb are blocks each made of an oxide magnetic material such as ferrite, 2a and 2b are thin films 3a and 3b each made of a magnetic metal such as sendust.

4a and 4b are non-magnetic materials such as glass, 5 is a magnetic gap, and 6 is a wire-wound window. In the head shown in FIG. 7, it is possible to perform sufficient recording even on a magnetic tape with high coercive force due to the sendust films 2a and 2b having high saturation magnetic flux density, and the ferrite blocks la and l with high magnetic permeability are used.
Due to the presence of b, sufficient reproduction characteristics can be obtained even in the high frequency range.

Also, ferrite blocks la, lb and sendust film 2a
, 2b has an inclination with respect to the magnetic gap 5, so this boundary does not act as a pseudo gap.

Next, the manufacturing process of the magnetic head shown in FIG. 7 is shown in FIGS.
This will be explained using Figure 0. First, as shown in FIG. 8, substantially V-shaped grooves 12 are provided in a ferrite block 11 at a predetermined pitch, and after melting and filling the grooves 12 with high melting point glass 13, surface polishing is performed. Next, as shown in FIG. 9, grooves 14 are formed between the grooves 12, and a sendust film 15 is formed on the surface where the grooves 14 are formed by a thin film forming technique such as sputtering or vapor deposition. Then, the grooves 14 in which the sendust film 15 is formed are also filled with high melting point glass, and the surface in which these grooves are formed is again subjected to surface polishing. As a result, a core half block 11a is obtained.

Then, a core half block 11b obtained by processing a winding groove is prepared from a core half block obtained in the same process as this core half block lla, and a pair of these core half blocks 11a are prepared.

11b are butt-jointed as shown in FIG.

A magnetic head core block as shown in FIG. 7 is obtained by cutting the core block thus joined along the two-dot chain line -N in FIG. 10.

<Problems to be Solved by the Invention> However, in the magnetic head as described above, since the abutting surface is inclined with respect to the surface on which the sendust film is formed,
In the process of processing the groove 12 shown in the figure, polishing the abutting surface, etc., even if the accuracy of the depth of the groove 12 or the accuracy of the amount of polishing is poor, the sendust films 2a and 2b shown in FIG. 7 do not face each other accurately. become. Similarly, even if the accuracy of the groove 14 processing and abutment surface polishing process shown in FIG. 9 is reduced, the Sendust [2a, 2b] will not face each other accurately.

Since the opposing portions of the sendust films 2a and 2b define the track width, it has been extremely difficult to improve the track width accuracy. Further, as the area of the facing portion decreases, the magnetic resistance increases and the magnetic efficiency of the magnetic head decreases. Therefore, there was a problem in that the product yield was reduced.

In view of the above-mentioned problems, the present invention provides a magnetic head having a structure that allows good magnetic recording and reproducing on a magnetic recording medium with high coercive force and that can easily improve the accuracy of various parts such as track width. The purpose is to

<Means for Solving the Problems> For this purpose, the present invention provides a core half pair each including an oxide magnetic block and a magnetic metal film formed on the block, such that the magnetic metal films are magnetically connected to each other. In a magnetic head in which the magnetic metal film on the medium sliding surface extends in the medium sliding direction with a constant width, and the oxide magnetic material is formed only on one side of the metal magnetic film. is arranged, and non-magnetic material is arranged in other parts.

<Function> In the magnetic head having the structure described above, even if the amount of polishing of the abutting surfaces of the pair of core halves changes, the opposing positions of the magnetic metal films do not change, and the opposing portions of the magnetic metal films on the medium sliding surface do not change. The length can be determined with extremely high accuracy, and since there is no boundary between the oxide magnetic material and the magnetic metal film within the track width determined by this, good magnetic recording and reproduction can be performed.

<Example> An example of the present invention will be described below with reference to the drawings.

FIG. 1 shows a magnetic head as an embodiment of the present invention,
In the figure, 21a and 21b are ferrite blocks 22a and 22b as oxide magnetic materials.

23a and 23b are non-magnetic materials such as high melting point glass, 24 is a magnetic gap, 25a and 25b are sendust films as magnetic metal films, and 26 is a wire-wound window.

As shown in the figure, the sendust films 25a, 25b extend on the medium sliding surface with a constant width in the medium sliding direction to both ends of the sliding surface, and within the track width formed by this head, the ferrite blocks 21a, 21b There is no boundary between Sendust Ui25a and 2sb. Therefore, this boundary does not act as a pseudo gap.

Next, the manufacturing process of the head shown in FIG. 1 will be explained below using FIGS. 2 to 6. First, as shown in FIG. 2, grooves 41 are formed in the ferrite block 31. This groove 41
has a surface that is substantially perpendicular to the groove forming surface and a surface that is inclined.

Next, as shown in FIG. 3, a sendust film 3 is applied to the groove forming surface.
5 is formed by a thin film forming technique such as sputtering or ion blating. At this time, it is desirable to take measures such as tilting the thin film forming jig so that the film thickness and film quality of the sendust film 35 formed on the surface perpendicular to the groove forming surface described above are constant.

Furthermore, as shown in FIG. 4, high melting point glass 33 is melted and filled into the groove in which the sendust film 35 is formed, and then the groove forming surface is polished. This groove forming surface will later become a medium sliding surface. Next, as shown in FIG. 5, U-shaped grooves 42 as shown are formed between the holes 41, respectively. Then, the surface facing upward in the figure is polished. This surface will become the butt surface in a later process. In this way, the core half block 31a is obtained.

Then, a core half block 31b obtained by the same process as this core half block 31a is used, in which the winding groove 37 is processed to b.

As shown in FIG. 6, these are marked A in the butt diagram.

The head chip as shown in FIG. 1 is obtained by cutting at the part shown in A.

In the manufacturing process as described above, even if the amount of polishing of the abutting surface and the media sliding surface changes, the Sendust 1i2 shown in Fig. 1
There is no adverse effect on the matching accuracy between 5a and 25b. Therefore, the track width can always be obtained with stable accuracy, and the yield can be improved.

<Effects of the Invention> As explained above, according to the present invention, it is possible to obtain a magnetic head that can perform magnetic recording and reproduction favorably on a magnetic recording medium with high coercive force and has high precision in various parts such as track width. .

[Brief explanation of drawings]

Figure 1 is a diagram showing the structure of a magnetic head as an embodiment of the present invention, Figures 2 to 6 are diagrams showing the manufacturing process of the head in Figure 1, and Figure 7 is an example of a conventional magnetic head. 8 to 10 are diagrams showing the manufacturing process of the head shown in FIG. 7. 21a, 21b are ferrite blocks, 22a, 22b
, 23a and 23b are non-magnetic materials, 24 is a magnetic gap, 25a and 25b are sendust films, and 26 is a winding window. 42 Figure 5 A'A' 1 7'') /2 /2 /Z If Figure 10

Claims (1)

[Claims] A magnetic head comprising a core half pair each including an oxide magnetic block and a magnetic metal film formed on the block, butted against each other so that the magnetic metal films face each other with a magnetic gap interposed therebetween, The magnetic metal film extends in the medium sliding direction with a constant width on the surface, and the oxide magnetic material is arranged only on one side of the metal magnetic film, and a non-magnetic material is arranged on the other part. magnetic head.