JPH01102707A - magnetic head - Google Patents

Abstract

PURPOSE:To prevent an S/N at the time of reproduction from being deteriorated by providing a gap part, and providing a core made of a magnetic material with prescribed width, a coil whose magnetic flux can be permitted to flow arranged on the core, and a conductive thin film being set at relation of normal plane with the thickness direction of the core and also arranged at least on a plane in the neighborhood of the gap part. CONSTITUTION:The conductive thin film 7 consisting of a conductive material is formed on the core 2 being set at the relation of almost normal plane with the direction of track width (t) and the end faces 6a and 6b of a gap member 3. By applying an electrical signal with a high frequency on the coil, a magnetic flux is generated in the neighborhood of the gap part, however, since the conductive thin film 7 consisting of the conductive material is formed on the core 2 and the end faces 6a and 6b of the gap part 3, a reactive magnetic flux due to an eddy current effect is formed, and as a result, the magnetic flux leaked from the conductive thin film 7 can be suppressed at a minimum quantity. In such a way, it is possible to improve the S/N at the time of reproduction.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic head used in magnetic recording and reproducing devices such as video tape recorders and digital audio tape recorders.

2. Description of the Related Art An example of a conventional magnetic head will be described below with reference to the drawings.

Figure 3 (al shows a side view of a conventional magnetic head;
Figure (b) shows its plan view. Moreover, FIG. 4 shows a plan view of a magnetic medium magnetized by the helical scanning method by the magnetic head shown in FIG.

The magnetic head 1 in FIG. 3 (al, (bl) is made of a magnetic material, and has two cores 2 having a trunk width t.
They are joined via a gap member 3 made of a non-magnetic material such as glass. Further, a coil 4 is wound around the core 2, and when a signal current is passed through the coil 4, a magnetic flux is generated, and this magnetic flux flows inside the core 2. Here, since the gap member 3 is made of a non-magnetic material, a large amount of the magnetic flux generated by the coil 4 leaks into the air near this gap, and leakage magnetic flux b1, b
This will form the second prize. Therefore, as shown in FIG. 4, the magnetic media 5 running opposite to this gap portion
If there is, a magnetized pattern 5a can be formed and an electric signal can be recorded.

Problems to be Solved by the Invention However, in the above configuration, leakage magnetic flux b2 is generated in addition to leakage magnetic flux b1, so that the magnetization pattern width of the magnetic medium is larger than the track width t. For example, even if an attempt is made to form a continuous magnetization pattern 5a with a track width t, a predetermined magnetization pattern will partially overlap with an adjacent magnetization pattern, and the S/N during reproduction will deteriorate. There was a problem.

Means for Solving the Problems In order to solve the above problems, the magnetic head of the present invention includes a core made of a magnetic material having a gap portion and a predetermined thickness, and a magnetic head disposed in the core so that magnetic flux flows. The coil and the thickness direction of the core are in a substantially normal plane relationship, and
A conductive thin film is provided on at least a surface near the gap portion.

Effect of the Invention With the above-described configuration, the present invention can reduce the leakage flux generated in a range larger than the track width, so that the S/N ratio during reproduction can be improved.

Embodiment Hereinafter, a magnetic head according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 (al shows a side view of a magnetic head according to an embodiment of the present invention, and FIG. 1 tb+ shows a plan view thereof.

Further, FIG. 2 shows a plan view of a magnetic medium magnetized by the helical scanning method by the magnetic head of the embodiment of the present invention shown in FIG. Note that common parts in the configuration described in the conventional example are omitted.

A conductive thin film 7 made of a conductive material is formed on the end surfaces 6a and 6b of the core 2 and the gap member 3, which are substantially perpendicular to the direction of the trunk width t.

Now, in this embodiment, when a high-frequency electric signal is applied to the coil, magnetic flux is generated near the gap, but the end surfaces 6a and 6b of the core 2 and the gear 7 member 3 are made of conductive material. Conductive information II! 7 is formed, a reaction magnetic field is formed due to the eddy current effect, and as a result, the magnetic flux leaking from the conductive thin film 7 becomes extremely small.

Therefore, there is a magnetic medium 5 running opposite to the gap portion as shown in FIG. Since it is possible to reduce the magnetic flux that tends to be distributed with a width of
A magnetization pattern that does not overlap with adjacent tracks can be formed, and a reproduced signal with good S/H can be obtained during reproduction.

Effects of the Invention As described above, the present invention includes a core made of a magnetic material having a gap portion and a predetermined thickness, a coil disposed in the core so that magnetic flux flows, and a thickness direction of the core that is approximately By providing a conductive thin film on a surface that is in the normal plane and at least near the gap, the eddy current effect of the conductive thin film is utilized to reduce unnecessary leakage magnetic flux 4 and improve the performance during playback. A magnetization pattern with good S/N can be recorded on magnetic media.

[Brief explanation of the drawing]

FIG. 1 (al is a side view of a magnetic head according to an embodiment of the present invention,
FIG. 1 (bl is a plan view thereof, FIG. 2 is a plan view of a magnetic medium magnetized by the helical scanning method by the magnetic head of the embodiment of the present invention shown in FIG. 1, and FIG. FIG. 3 is a side view of the magnetic head, and FIG. 3 is a plan view thereof, and FIG. 4 is a plan view of a magnetic medium magnetized by the helical scan method by the conventional magnetic head shown in FIG. 1...Magnetic head, 2...Core, 3.
・Gap member, 4... Coil, 5...
... Magnetic media, 5a... Magnetization pattern,
7... Conductive thin film. Name of agent: Patent attorney Toshio Nakao.

Claims (1)

[Claims] a core made of a magnetic material having a gap portion and having a predetermined thickness; a coil disposed in the core so that magnetic flux flows;
A magnetic head characterized in that a conductive thin film is provided on a surface that is substantially normal to the thickness direction of the core and at least near the gap portion.