JPH0658724B2 - Magnetic head - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head of a digital recording / reproducing apparatus such as a flexible disk.

2. Description of the Related Art As a conventional magnetic head of this kind, the structure shown in FIG. 3 is adopted, and a recording / reproducing core (1) having a recording / reproducing gap (11) formed in advance and a recording / reproducing core (1) are sandwiched therebetween. The sliders (20) and (2b) provided on the above are bonded with glass, resin, or the like. The core (1) is generally made of Mn-Zn ferrite material. As means for increasing the density of such a magnetic head, there are a method of improving the recording density in the tape running direction and a method of improving the track density in the tape width direction.

When the track axis (T) of the magnetic head is narrowed in order to improve the track density, the ferrite of the core (1) is subjected to strain during processing, causing deterioration of magnetic permeability in magnetic characteristics, etc.
The recording / reproducing efficiency of the magnetic head is reduced. Therefore, conventionally, as shown in FIG. 4, a method has been put into practical use in which the track tip portion of the core (1) is grooved to improve the track density. This is generally called a bulk type magnetic head, and the groove (8) is processed in the vicinity of the gap (11) of the core (1), and the groove (8) is molded with glass (3) or the like. With this structure,
The track width of the magnetic head is restricted to (Tw), and the core (1)
The influence at the time of processing can be improved by processing only the tip of the track without narrowing the material itself.

Problems to be Solved by the Invention However, even with this structure, the limit is 200 TPI (track width of about 100 μm), and further improvement in track density cannot be expected.

In order to improve the recording density in the tape running direction, the coercive force tends to be increased (1000 Oe to 1400 Oe) on the magnetic medium surface in order to reduce the demagnetizing field at the time of recording and improve the short wavelength recording characteristic. On the other hand, in the magnetic head, the gap is narrowed to reduce the recording / reproducing loss. Therefore, the gap (11) of the magnetic head is saturated at the time of recording, and improvement of the core material itself has been required for higher density.

Therefore, the present invention is intended to improve the above-mentioned problems, and it is an object of the present invention to improve track density and enable short wavelength recording in order to cope with higher density.

Means for Solving the Problems In order to achieve the above object, the present invention provides a magnetic thin film yoke that is formed between a ferrite and a ferrite bulk material so as to have a width narrower than that of the ferrite and that can regulate a recording / reproducing track width. The ferrite bulk material is arranged in a boat shape capable of regulating the gap depth dimension, the medium contact surface portion on the ferrite is molded with glass, and the glass mold is formed to a position deeper than the gap depth. Is.

With such a structure, the recording / reproducing track width of several tens of μm can be regulated by the width of the magnetic thin film yoke, and the track density can be improved. Moreover, the thin film magnetic material has a saturation magnetic flux density of 10,000 G and ferrite. It is higher than the material (5000G), narrower gap is possible, and short wavelength recording characteristics can be improved.
Moreover, since the medium contact surface portion on the ferrite is molded with glass, the ferrite bulk material is close to the magnetic thin film yoke and separated from the ferrite, so that the track width is surely equal to the width of the magnetic thin film yoke. Further, by controlling the gap depth dimension, which has an important influence on the recording / reproducing efficiency of the magnetic head, by the ferrite bulk material, it becomes possible to facilitate its manufacture. Further, since the glass mold is formed deeper than the gap depth, the magnetic efficiency is improved.

Example One example of the present invention will be described below. FIG. 1 is a structural diagram of an embodiment of the present invention, and FIG. 2 is a II- line in FIG.
It is a II sectional view.

On one ferrite (6) forming a magnetic circuit, the catalyst contact surface is molded with glass (5) or the like, and a magnetic thin film yoke (4) having a track width, for example, Ni _sowt% -Fe _zowt% is sputtered, It is formed by the plating method. The ferrite bulk material (7) that forms the other magnetic circuit is processed into a boat shape. Thereby, a recording / reproducing gap is formed and a magnetic circuit is constructed. With this structure, the track width is the width of the magnetic thin film yoke (4).
(T _w2 ), gap depth (d) is ferrite bulk material
It is determined by the ship shape in (7). Glass as shown (5)
Is formed deeper than the gap depth (d), and the width (T _W2 ) of the magnetic thin film yoke (4) is ferrite (6).
Is formed to be narrower than the width of.

The thin film yoke (4) can be accurately processed to about 10 μm (± 20 μm) by using photolithography technology.

According to the above configuration, the recording / reproducing track width is regulated by the width (T _W2 ) of the magnetic thin film yoke (4), so that it can be made smaller than the conventional one, and the track density can be improved. . Moreover, by using the magnetic thin film yoke (4), the saturation magnetic flux density can be increased, the gap can be narrowed, and the short wavelength recording characteristic is also improved. Further, since the gap depth is regulated by the ferrite bulk material, the structure can be made easy.

As described above, according to the present invention, since the recording / reproducing track width regulated by the width of the magnetic thin film yoke can be made narrower than the conventional one, the track density can be improved and the ferrite Since the upper medium contact surface portion is molded with glass, the ferrite bulk material is close to the magnetic thin film yoke and separated from the ferrite, so that the track width can be surely made equal to the width of the magnetic thin film yoke,
Also, by using the magnetic thin film yoke, it is possible to improve the short wavelength recording characteristic by narrowing the gap, and since the glass mold is formed to a position deeper than the gap depth, it is possible to improve the magnetic efficiency. Since the gap depth is regulated by the ferrite bulk material,
Its manufacture can be facilitated.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of the present invention, FIG. 2 is a sectional view taken along line II-II in FIG. 1, FIG. 3 is a perspective view of a conventional example, and FIG. 4 is an enlarged view of a main part of the conventional example. is there. (4) …… Thin film magnetic yoke, (7) …… Ferrite bulk material,
(T _W2 ) ... width

Claims (1)

[Claims] 1. A magnetic thin film yoke, which is formed narrower than the ferrite and can regulate the recording / reproducing track width, is arranged between the ferrite and the ferrite bulk material, and the ferrite bulk material is provided with a gap depth dimension. Is formed into a ship shape capable of restricting, the medium contact surface portion on the ferrite is molded with glass, and the glass mold is formed to a position deeper than the gap depth.