JPS6174112A - Magnetic head - Google Patents

Abstract

PURPOSE:To obtain a sufficient electromagnetic exchange characteristic by cutting off a corner of a magnetic film of a winding side of the 1st core half and making the upper ridge almost horizontal to the corner of the 1st core half so as to reduce the amount of exposure of the magnetic thin film. CONSTITUTION:The corner 15 of the 1st magnetic thin film 7 coated on the 1st core base 2 formed with the winding part 4 is cut off obliquely. Then the upper ridge 16a of the missing part 16 is made nearly horizontal with the corner 14 of the 1st core base 2 and the vertical distance form the corner 14 to the medium sliding face is made <=20mum. In this state, when the slide face is polished up to alternate long and two short dashes line a-a, the depth of gap with <=20mum is attained. Thus, the depth of the gap and the exposure of the magnetic thin film are small and a sufficient electromagnetic exchange characteristic is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic head, and in particular to a core base whose side surface facing a magnetic gap is inclined with respect to the magnetic gap surface, and a core base of the core base. The present invention relates to a magnetic head having a core half including a magnetic thin film made of a magnetic material having a high saturation magnetic flux density and deposited on the side surface facing the magnetic gap.

[Conventional technology]

In recent years, in the field of magnetic recording devices, improving recording density has become one of the most important technical issues.

In order to improve the recording density, it is necessary to increase the coercive force of the magnetic recording medium and to improve the strength of the recording magnetic field in the gap portion of the magnetic head. In order to meet these demands, magnetic recording media using metals with high coercive force were developed, while magnetic heads were developed with narrow gap lengths to generate strong magnetic fields. being developed.

However, conventional magnetic heads mainly use ferrite material, and the saturation magnetic flux density Bs of ferrite material is 4000 to 5.
000 Gauss, there is a limit to the strength of the recording magnetic field that can be obtained even if the gap is narrowed, and there is a problem that sufficient recording characteristics cannot be obtained with magnetic recording media such as metal having a high coercive force.

In order to solve the above-mentioned problem, the inventor of the present invention, as a result of intensive research, first developed a core in which a magnetic thin film made of a magnetic material having a high saturation magnetic flux density was coated on the side surface facing the magnetic gap of the core base. A magnetic head using half bodies was proposed (Japanese Patent Application Laid-open No. 155513/1983).

FIGS. 3 to 6 show previously proposed magnetic heads. Here, FIG. 3 is a perspective view of the magnetic head of the first known example, FIG. 4 is an enlarged sectional view showing details of the gap portion of the magnetic head of FIG. 3, and FIG. 5 is a magnetic head of the second known example. 6 is an enlarged sectional view showing details of the gap portion of the magnetic head of FIG. 5. FIG.

In these figures, ■ is the first core half body, and 2 is the first core base constituting the first core half body 1.

3 is a second core half body, 4 is a second core base constituting the second core half body 3, 5 is a winding window, and 6 is a magnetic gap. As shown in FIGS. 3 and 4, a magnetic thin film 7°8 made of a magnetic material having high saturation magnetic flux density and high magnetic permeability is deposited on the side surface of the core substrates 2 and 4 facing the magnetic gap 6. has been done.

For the first core base 2 and the second core base 4, a ferrite having high magnetic permeability, such as Mn-Zn ferrite or Ni-Zn ferrite, is used. On the other hand, the first magnetic thin film 1II7 and the second magnetic thin film 8 are made of, for example, a Fe-Al-8i alloy.

Crystalline alloys such as Fe-5i alloys and FeNi alloys,
A1. Be.

Sn, Mo, wT Tll Mn+ Cr, Zr+ N
An alloy to which elements such as b are added, or an alloy containing the above-mentioned additional elements with Co and Zr as the main components, etc. are used.

As shown in FIGS. 5 and 6, the magnetic head of the second known example has a magnetic thin film [9, to] and a non-magnetic material 11 on the side surface of the core bases 2 and 4 facing the magnetic gap 6. Alternately laminated thin films 12, 13 are applied.

Core substrate 2.4 material, magnetic thin film 9. The material of IO is the same as that shown in the above-mentioned first known example. As the non-magnetic material 11, for example, Si2 is used.

Among such magnetic heads, the first known example magnetic head is as follows:
Since the gap portion of the core half 1.3 is made of a material with high saturation magnetic flux density and high magnetic permeability, the saturation magnetic flux density and magnetic permeability of the chain portion are improved accordingly, and a strong recording magnetic field can be generated. The effect is that it can occur.

On the other hand, in the magnetic head of the second known example, the gap portion between the core halves 1゜3 is formed of a laminated thin film 12゜13 made by laminating a material having high saturation density and high magnetic permeability and a non-magnetic material. Therefore, in addition to the effects of the first known example, there is an effect that eddy current loss is reduced and recording efficiency is improved.

[Problem that the invention seeks to solve]

However, the conventional magnetic head described above has a first magnetic thin film! ! I
7 or a first laminated thin film 12 in which magnetic thin films 9 and 10 and nonmagnetic material 11 are alternately laminated is deposited on the surface of the first core substrate 2 to a uniform thickness.

As shown in FIG. 4 or 6, a corner 1 formed by the surface of the core base 2 facing the gap and the winding window 5
4, the first magnetic thin film 11g7 or the first laminated thin film 12
The position of the corner portion 15 of is lowered.

Therefore, in the magnetic head of the first known example.

When polishing the upper surface of the magnetic head to form the sliding surface of the magnetic recording medium, if the polishing is performed only up to the corner 14 of the first core base 2 (up to the chain double-dashed line a-a in FIG. 4), the gap depth will increase. This corner part becomes larger than 14, making it impossible to obtain sufficient electromagnetic exchange characteristics.

Up to the corner 15 of the first magnetic thin film 7 (double-dot chain mb in FIG.
-b) When polished, there is a problem that the gap length increases and the wear characteristics deteriorate.

Also, in the magnetic head of the second known example, if only the corners 14 of the first core base 2 are polished (up to the two-dot chain line a-a in FIG. 6), the gap depth becomes large and is insufficient! If the magnetic exchange characteristics cannot be obtained and the non-magnetic material 11 is polished below this corner 14 (up to the two-dot chain line bb in FIG. 6), the non-magnetic material 11 will be exposed on the sliding surface. This causes a problem in that the armpit area becomes a false gap, making it impossible to perform normal recording.

[Means for solving problems]

In order to eliminate the above-mentioned drawbacks of the prior art, the present invention provides a first thin film having a magnetic material with high saturation magnetic flux density and high magnetic permeability deposited on a first core substrate in which a single winding window is formed. ,
A corner formed by the surface facing the magnetic gap and the winding window is cut out, and the upper edge of the cutout is formed between the surface of the first core base facing the magnetic gap and the winding window. The corner portion formed by is set at a substantially horizontal position.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 is a sectional view of a gap portion of a magnetic head showing a first embodiment of the present invention.

The first embodiment of the present invention is an embodiment applied to the magnetic head of the first known example described above, and similar members are indicated by the same reference numerals.

In this embodiment, a corner 15 of the first magnetic thin film 7 adhered to the first core base 2 in which the winding window 4 is formed is cut obliquely. The upper edge 1 of this cutout 16
6a is below the corner 14 of the first core base 2, and the distance from the corner 14 in the vertical direction to the medium sliding surface is 20.
It has been cut to have an ALI of 11 or less.

This cutout 16 is polished before bonding of the core halves 1.3.

The magnetic head of this embodiment has a corner portion 1 of a first core base 2.
If the sliding surface is polished to a depth of 4 (up to the chain double-dashed line a-a in FIG. 1), a gap depth of 20 .mu.m or less can be obtained, and sufficient electromagnetic exchange characteristics can be obtained. Furthermore, the first magnetic thin film 7 is not exposed beyond the thickness of the deposited magnetic thin film, and its wear resistance does not deteriorate.

FIG. 2 is a front view of a gap portion of a magnetic head showing a second embodiment of the present invention.

The second embodiment of the present invention is an embodiment applied to the magnetic head of the second known example described above, and similar members are designated by the same reference numerals.

In this embodiment, a corner 15 of the first laminated thin film 12 adhered to the first core base 2 in which the winding window 5 is formed is cut obliquely. and.

The upper edge 17a of this cutout 17 is cut below the corner 14 of the first core base 2 so that the distance from the corner 14 in the vertical direction to the medium sliding surface is 20 μm or less. has been done.

By processing in this way, the non-magnetic powder 22 is not exposed on the sliding surface, and it is possible to eliminate the conventional problem of forming a pseudo gap. That pond,
The method of machining the cutout portion 17 and the effect of providing the cutout portion 17 are the same as in the case of the first embodiment described above.

〔Effect of the invention〕

As explained above, the magnetic head of the present invention is provided.

The upper edge of the cutout and the first By reducing the vertical distance between the surface of the core base facing the magnetic gap and the corner of the winding window, the gap depth and magnetism '7! ! The amount of exposed film is small in both cases. Therefore, it is possible to obtain sufficient electromagnetic exchange characteristics and can be applied to recording on a magnetic recording medium having a high coercive force, and the durability is significantly improved.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a gap portion of a magnetic head showing a first embodiment of the invention, and FIG. 2 is an enlarged sectional view of a gap portion of a third magnetic head. FIG. 5 is a perspective view showing another example of a conventional magnetic head. ↓ FIG. 6 is an enlarged sectional view of the gap portion of the fifth magnetic head. 1...First core half, 2...First core base, 3...Second core half, 4...
...First core base, 5... Winding window, 6...
...Magnetic gap, 7...First magnetic thin film,
8...Second magnetic thin film, 9.10...
Magnetic thin film, 11...Nonmagnetic material, 12...First laminated thin film, 13...Second laminated thin film, 14
．． 15... corner, 16.17 old... cutout, L
6a, 17a... Upper edge Fig. 1 Foil 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6

Claims (1)

[Claims] a first core half having a magnetic thin film made of a magnetic material having a high saturation magnetic flux density adhered to the side surface facing the magnetic gap of the first core base body having a winding window; and a winding window. A second core half body having a magnetic thin film made of a magnetic material having a high saturation magnetic flux density is attached to the opposite side surface of the second core body through a magnetic gap. In the magnetic head formed by joining the first
A corner portion formed by the surface facing the magnetic gap and the winding window of the first thin film adhered to the core substrate of is cut out, and the upper edge of the cutout portion is attached to the medium sliding surface. A magnetic head characterized in that the vertical position is close to a corner formed by the surface of the first core base facing the magnetic gap and the winding window.