JPS6015805A - Magnetic head - Google Patents

Abstract

PURPOSE:To attain the recording with high density and the reproduction with high sensitivity by using a ferrite material to the surface which rubs a recording medium and providing a thin film having high saturation magnetic flux density and high permeability on the main magnetic path forming surface of a core. CONSTITUTION:A working gap 4 is formed vertically to a surface 3 which rubs a recording medium, and a ferrite core 1 is set opposite to the gap 4. A material 2, e.g., ''Permalloy '' having high magnetic saturation flux density Bs and high permeability mu is formed on both sides of the main magnetic path forming surface of the core 1 in <=10mu thickness by a sputtering process, etc. As a result, the magnetic flux can be concentrated and both Bs and mu are increased by about 30% for a magnetic head compared with the conventional head. This ensures the recording with high density and the reproduction with high sensitivity.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a magnetic head that is optimal for high-density magnetic recording and high-sensitivity reproduction of high-coercive force media.

Conventional Structure and Problems Conventionally, magnetic heads used in video tape recorders (VTRs) have been made of alloy-based magnetic materials. However, with the advent of high-frequency customization, ferrite materials with excellent workability and wear resistance, heads made of ferrite and having the shape shown in FIG. 1 have now become mainstream. In the figure, reference numeral 1 indicates the main magnetic path forming surface of the core, and in the past, no groove was formed on this surface.

Recently, with the demand for smaller, lighter, and longer-lasting VTR equipment, there has been a demand for higher-density recording.

When vapor-deposited tapes and the like came into use, the following drawbacks became apparent.

First, the basic properties of ferrite materials are that saturation magnetic flux density BS and magnetic permeability μ show a correlation, and materials with high μ are B
A material with a small S and a large BS has a low μ.
I have a residence. On the other hand, as described below, magnetic heads have the property that BS is not important during recording and μ is important during playback. In the case of a recording/reproducing head that satisfies both characteristics, and uses a high coercive force medium, it is possible to record at high density with a single hennode instead of using a conventional ferrite magnetic head. At the same time, it is difficult to reproduce with high sensitivity.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned problems and aims to provide a magnetic head that satisfies both high-density recording and high-sensitivity reproduction.

Structure of the Invention The present invention achieves the above object, and includes: an operating gap provided perpendicularly to a sliding surface that slides opposite to a recording medium;
and a ferrite material provided facing each other across the operating gap, at least the sliding surface is formed of the ferrite material, and a thin film having a high saturation magnetic flux density and high magnetic permeability is provided on the main magnetic path forming surface. The present invention provides a magnetic head characterized by the following.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below. FIG. 2 is a perspective view of a magnetic head in one embodiment of the present invention. In this embodiment, a material 2 having a high BS and a high μ, such as permalloy, is formed with a thickness of 10 μm or less on both sides of the main magnetic path forming surface of the ferrite core 1 by sputtering or the like. 3 is a sliding surface, and 4 is an operating gap.As in this example, a high B is provided on the main magnetic path forming surface.
By providing S/high μ material, concentration of magnetic flux is achieved,
The head's saturation magnetic flux density BS and magnetic permeability μ are nearly 30% larger than those of conventional heads, allowing for high-density recording and highly sensitive reproduction (IJ performance).

However, ',',, :3 Bs/high μ material becomes /I when it becomes 10μ or more? Although there is no physical change, the chip thickness of the head becomes thicker, which is wasted, and eddy current loss also increases.

In this case, 2t of high BS and high μ material formed on the main magnetic path forming surface.
rJ does not need to be formed on the entire surface of the main magnetic path forming surface, and may be formed at least in the vicinity of the working gap.

It goes without saying that the high BS/high .mu. material is not limited to the 2-ij varnish battering method, but may be formed by other thin film forming methods such as vapor deposition or ion blasting.

Effects of the Invention As described above, the present invention includes a working gap provided perpendicularly to a sliding surface that slides facing a recording medium, and a ferrite core provided facing each other across the working gap, and at least a sliding surface. The moving surface is made of ferrite material, and is the throat of the head, which is characterized by the fact that a thin film with high saturation magnetic flux density and high magnetic permeability is provided on the main magnetic path forming surface of the core. It has the advantage of increasing the saturation magnetic flux density and magnetic permeability, making high-density recording and high-sensitivity reproduction possible, and being compatible with high coercive force media such as meckle tape and vapor-deposited tape, making it a great contribution as a head for high-definition VTRs.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a conventional ferrite magnetic head, and Figure 2 is a perspective view of a conventional ferrite magnetic head.
FIG. 1 is a perspective view showing a magnetic head that is an embodiment of the present invention. 1...Core, 1/...Main magnetic path forming surface, 2
゛・°・Pa high saturation magnetic flux density/high magnetic permeability material, 3...
・Sliding surface, 4...Operating gap. Name of agent: Patent attorney Toshio Nakao and 1 other person 1st
figure

Claims (1)

[Claims] An operating gap provided perpendicularly to a sliding surface that slides facing the recording medium, and a ferrite core provided facing each other across the operating gap, and at least the sliding surface is formed of a ferrite material. A magnetic head characterized in that a thin film having a high saturation magnetic flux density and high magnetic permeability is provided on the main magnetic path forming surface of the core.