JPS6035311A - Vertical magnetic recording head - Google Patents

Abstract

PURPOSE:To enable taking out of a large reproduced output with a smaller number of turn by providing a main magnetic pole, a coil winding the main magnetic pole and a transformer coupled magnetically to a part of the coil. CONSTITUTION:A main magnetic pole 1 permits reduction in a relief 7 in a non- magnetic part in order to make a coil 1 of single turn. The magnetic flux passing through the pole 1 is thus increased and a voltage is generated efficiently in the coil 3 of single turn. Such voltage is increased by the coil 9 formed at the other end of the coil 3 and said voltage is utilized as a signal. A transformer 8 is adhered tightly to a base 5 and is made into the transformer of a closed loop having good efficiency as the magnetic flux passes through the base 5. The output is taken out from a part where the efficiency is good by forming the head into the single turn step-up type as mentioned above and therefore the number of turn is decreased. Since the transformer part having a large number of turn can be made into a separate body, the manufacture is made easy.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic head used for magnetic recording in tape recorders, VTRs, etc. that record signals such as audio or video, and particularly relates to a perpendicular magnetic recording head for perpendicular recording media. It is something.

Conventional configurations and their problems In recent years, perpendicular magnetic recording heads, along with perpendicular magnetic recording media, have been developed by various companies and Active research is being carried out at universities, and energetic presentations are being made at academic conferences, newspapers, etc.

A conventional example will be explained below.

FIG. 1 is a first conventional example showing the basic type of perpendicular magnetic recording. The main magnetic pole 1 faces the auxiliary magnetic pole 2 at a distance of 60 to 100 μm, and the auxiliary magnetic pole 2 is wound with a coil 3 for recording and reproducing. The perpendicular magnetic recording medium 4 moves through the gap between the main magnetic pole 1 and the auxiliary magnetic pole 2 while being pressed against the main magnetic pole 1.

Considering a disk as an example of applying the first conventional example to a device, the main magnetic pole 1 and the auxiliary magnetic pole 2 are placed opposite to each other with the disk in between, and the gap between the main magnetic pole 1 and the auxiliary magnetic pole 2 is kept at 50 to 100/1 m. The auxiliary magnetic pole 2 must be moved at the same time,
A strong U-shaped arm is required, with the main magnetic pole 1 attached to one end and the auxiliary magnetic pole 2 attached to the other end. In order to prevent resonance and maintain accuracy, this arm has to be quite large, has a large weight, increases inertial mass, increases access time, and complicates the device.

On the other hand, for tape-shaped perpendicular magnetic recording media, the current V
The helical scan method, which is a high-density recording scanning method that is the mainstream in TR, cannot be used, and the tape speed must be increased, resulting in a fixed head method, which imposes significant restrictions on device design.

FIG. 2 shows a second conventional example that is constructed of only one side, similar to the ring head.

The main magnetic pole 1 is attached in contact with a base material 6 forming a closed magnetic path, and a coil 3 is wound around the base material 5. The main magnetic pole 1 and the base material 5 are in pressure contact with the perpendicular magnetic recording medium 6, forming a closed magnetic path of the main magnetic pole 1, the base material 5, the perpendicular magnetic recording medium 6, and the main magnetic pole 1. Since the diameter of the wire used for the coil 3 is several tens of μm, the height of the relief 7 of the base material 6 must be 0.1 mm or more.

As a result, the main pole 1 inevitably becomes longer. However, as shown in FIG. 3, the magnetic flux passing through the main magnetic pole 1 decreases exponentially as the distance from the perpendicular recording medium 6 increases as the magnetic flux leaks within the main magnetic pole 1. Therefore, in order to obtain sufficient reproduction output from the coil 3, the number of turns must be increased, which increases impedance and degrades performance. That is, it is practically impossible to wind the coil 3 in multiple turns.

FIG. 4 shows a third conventional example in which the coil 3 is formed of a thin film. A non-magnetic material such as glass is molded into the relief 7 of the base material 5, and the thin film coil 3 and the main magnetic pole 1 are formed thereon. With this method, the output can be obtained from the coil 3 at a position where the magnetic flux passing through the main pole 1 is large, so the output per number of turns is larger compared to the second conventional example.
Since the number of turns is small, the playback output is small.

Multi-turn thin film coil 3 to obtain larger playback output
Conventional examples having this are shown in FIGS. 5 and 6.

In the conventional example shown in FIG.
However, in order to make multiple turns, it is necessary to lengthen the main magnetic pole 1, and as shown in Figure 3, the output decreases according to the length of the main magnetic pole 1. cannot obtain sufficient effect.

On the other hand, there is a conventional example shown in FIG. 6 as a means of shortening the main magnetic pole 1 and winding it in multiple turns. In this example, a main magnetic pole 1 is fabricated perpendicularly to a base material 6, and a coil 3 is fabricated around it. However, in this example, it is difficult to produce a thin main pole 1 and the area occupied by the coil 3 becomes large, and the magnetic path for the magnetic flux passing through the main pole 1 to return to the tape 6 becomes long, making it difficult to obtain sufficient efficiency. .

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional problems, and an object thereof is to provide a perpendicular magnetic recording head of a single-side access type with a large reproduction output.

Structure of the Invention The present invention is a perpendicular magnetic head that includes a main magnetic pole, a coil around the main magnetic pole, and a step-up transformer, and is capable of producing a large reproduction output with a small number of windings.

Description of examples An embodiment of the present invention is shown in FIG.

The main magnetic pole 1 is formed on a base 5 made of a high magnetic permeability material such as ferrite, and a relief 7 provided on the base 6 is provided so that the magnetic flux is concentrated on the main magnetic pole 1. It is made of non-magnetic material or air gaps. coil 3
winds the main magnetic pole 1 on the same plane as the main magnetic pole 1, and winds the coil 3
The other side forms a closed loop on the second surface 12 adjacent to the first surface 1o of the base 5 on which the main magnetic pole 1 is formed, thereby creating a one-turn coil. A transformer 8 is attached to the second surface 12 by adhesive. This transformer 8 has
A coil 9 of enamelled wire is wound from several turns to several tens of turns. The configuration of lance 8 is shown in FIG. coil 9
is wound along the center of the transformer 8.

The operation of FIG. 7 will be explained. Since the main magnetic pole 1 has one turn of the coil 3, the relief 7 of the non-magnetic part can be made small.

Therefore, as shown in FIG. 3, the magnetic flux passing through the main magnetic pole 1 becomes large, and a voltage is efficiently generated in the coil 3 of one turn.

This voltage is boosted by a coil 9 formed at the other end of the coil 3, and the resulting voltage is used as a signal. The transformer 8 is closely attached to the base 5, and the magnetic flux passes through the base 6, making it a highly efficient closed-loop transformer.

As described above, according to this embodiment, by adopting the one-turn step-up type, the output can be taken out at an efficient location, the number of turns can be reduced, and the transformer section with a large number of turns can be made separate. Manufacturing becomes easy.

Other embodiments of the invention are shown in FIGS. 9 and 10.

In the embodiment shown in FIG. 9, the intersection line between the surface on the base 6 formed by the main pole 1 and the surface on the base 5 on which the transformer 8 is arranged is chamfered.

First, the coil 3 on the surface 10 on which the main pole 1 is formed is deposited. At this time, the material of the coil 3 to be vapor deposited is formed on the chamfered portion 11. On the other hand, the surface 12 on which the transformer 8 is formed
When depositing the upper coil 3, the material of the coil 3 is also deposited on the chamfered part 12, and the coil 3 completes a closed loop.
It becomes a 1 turn coil.

In the embodiment shown in FIG. 1o, the chamfered portion 11 shown in FIG. 9 is shaped like an arc, and the same effect as chamfering can be obtained.

With the above configuration, a one-turn coil can be made of a thin film, and an electrically coupled one-turn coil can be created by vapor deposition from two directions.

Note that the coil may be formed using a vapor-deposited thin film only on the surface 1Q, and the coil on the surface 12 may be formed by another method.

Effects of the Invention By providing a step-up transformer, the perpendicular magnetic recording head of the present invention can produce high reproduction output with a small number of windings, and its practical effects are outstanding.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a conventional perpendicular magnetic recording head;
The figure is a perspective view showing another conventional perpendicular magnetic recording head.
The figure is a characteristic diagram showing the relationship between the magnetic flux passing through the main pole and the distance from the perpendicular recording medium, FIG. 4a. b is a plan view and a front view of a conventional one-turn thin film head;
FIG. 6 is a front view showing a conventional multi-wound thin film head, FIG. 6 is a main view showing another conventional multi-wound thin film head, and FIG. 7 is a perpendicular magnetic recording head of the first embodiment of the present invention. FIG. 8 is a perspective view showing details of the transformer in the same embodiment, and FIGS. 9 and 10 are perspective views of main parts of other embodiments of the present invention. 1.・Main magnetic pole, 3... Coil, 5...
Base, 8...Transformer, 10...First surface, 12
...Second side. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3 ■ Distance - Figure 4 (4) Figure 5 Figure 6

Claims (1)

[Claims] A perpendicular magnetic recording head comprising a main magnetic pole, a coil around the main magnetic pole, and a transformer magnetically coupled to a part of the coil.