JPS5853017A - Vertical magnetic recording and reproducing head - Google Patents

Abstract

PURPOSE:To decrease errors due to the accumulation of dust at the tip of a magnetic shaft, by arranging a compressed air delivery unit at the head of a main magnetic pole and bringing the magnetic shaft of a main magnetic pole into contact with the surface of a magnetic recording medium at the upper side with compressed air at recording and reproduction only. CONSTITUTION:An air delivery unit 9 is arranged at the head of a main magnetic pole 3. This unit 9 has an air reservoir 12 pressing the main magnetic pole 3 and an air reservoir 11 having a compressed air delivery inlet 10 to which compressed air A0 is delivered, and a throttle device 13 regulating the pressure is formed between the air reservoirs 11 and 12. A vertical magnetic recording and reproducing head is positioned under a magnetic recording medium A, the compressed air A0 is delivered to the air reservoir 11 only at the recording and reproduction of information and a magnetic shaft 1 of the main magnetic pole 3 is brought into contact with the magnetic recording medium A under a specified pressure, allowing to eliminate errors due to accumulation of dust at the tip of magnetic shaft.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a perpendicular magnetic recording/reproducing head.

A magnetic recording method using a ring-shaped magnet currently used in tape recorders and the like uses a magnetization vector in the longitudinal direction of the recording medium to perform recording and reproduction. When recording information in a ring-shaped magnetic field using a magnetic recording method that uses dots to increase the density of recorded information and narrow the bit spacing, the strength of magnetization decreases due to the demagnetization effect within the magnetic recording medium. In addition, rotation of the magnetization vector occurs within the cross section of the magnetic recording medium, significantly reducing the reproduction output of recorded information. Therefore,
In order to enable high-density magnetic recording, a perpendicular magnetic recording method in which the demagnetization effect is close to zero is required.

This perpendicular magnetic recording method includes the method of Professor Iwasaki of Tohoku University. Figure 1 is a diagram illustrating a conventional perpendicular magnetic recording and reproducing method for perpendicular magnetic recording and reproducing of information on a magnetic recording medium used in Professor Iwasaki's method. A coil 4 is wound around a main magnetic pole 3 whose periphery is covered with a protective material 2 such as a plastic material, and a high magnetic permeability ferrite material facing the main magnetic pole 3 with the magnetic recording medium A interposed therebetween. An auxiliary magnetic pole 5 is provided.

In such a conventional perpendicular magnetic recording head, (1) the main magnetic pole 6 and the auxiliary magnetic pole 5 are arranged separately on both sides of the magnetic recording medium A, so it is difficult to align the main magnetic pole 6 and the auxiliary magnetic pole 5; Not only that, but it was also unsuitable for disc, C, or multiplayer.

(2) Main magnetic pole 3 and auxiliary magnetic pole 5. ! Since the magnetic circuit formed by ; becomes an open magnetic path, the lines of magnetic force spread widely in space, reluctance (magnetic resistance) increases, and energy efficiency deteriorates. Therefore, it is necessary to pass a large current through the coil 4 of the auxiliary magnetic pole 5 during recording, and when reproducing? Since the magnitude of the output depends on the strength of the magnetization vector, which is the signal source of the magnetic recording medium, and is inversely proportional to the roughtance of the magnetic circuit, there are drawbacks such as extremely poor reproduction S/N ratio.

Therefore, the present inventors proposed a method for perpendicular magnetic recording and reproduction that eliminates the above-mentioned drawbacks. FIG. 2 is a diagram showing the configuration of the perpendicular magnetic recording and reproducing mode, and the magnetic recording medium A is
It is made of a material that exhibits strong uniaxial anisotropy in the direction perpendicular to the film surface of the magnetic layer 6. The material of this magnetic layer 6 is Or
-ColGd-Co.

There are Gd-Fe, Tb-Fe, and Dy-Fe RF snow films (7 types) and MnB1 vapor-deposited films.Base layer 7
is a substrate made of glass, ceramic, resin, plasti, resin, etc., on which a thin film of a high permeability magnetic material such as Eva, Permalloy, Mn, Zn ferrite, etc. is formed by a coating method, a tarring method, etc., or a Permalloy plate 9Mn- Use only a high permeability plate such as a Zn fullite plate. The main magnetic pole 6 has its tip in contact with the surface of the magnetic layer 6 of the magnetic recording medium A, and has a magnetic axis 1 of a thin strip made of a magnetic material with high magnetic permeability perpendicular to the surface. 1 surrounded by a soft protective material 2. The reason why soft plastic, glue, etc. is used as the material for the protective material 2 is that the tip of the strip 1 is in contact with the magnetic layer and will wear out.
At this time, the purpose is to allow the protective material 2 to be sharpened in the same way as sharpening a pencil to expose the lead.

The magnetic shaft 1 is made of, for example, permalloy+Mn-Zn ferrite, and its size is set to be approximately several μm in width and 1 μm or less in thickness.

The auxiliary magnetic pole 5 is provided so as to surround the main magnetic pole 3 with a small gear spaced therebetween. That is, the main magnetic pole 6 is movable within the auxiliary magnetic pole 5.

A coil 4 is wound around the auxiliary magnetic pole 5, and the magnetic field is determined by the current flowing through the coil 4 and the number of turns of the coil 4. The yoke auxiliary magnetic pole 8 has magnetic lines of force extending from the auxiliary magnetic pole 5 to the magnetic axis 1 of the main magnetic pole 3. Magnetic layer of magnetic recording medium A6. Base layer 7
and the yoke auxiliary magnetic pole 8 to form a closed magnetic path.

The yoke auxiliary magnetic pole 8 is made of a high permeability magnetic material with good frequency characteristics, such as two-light. The structure is such that a minute gap is created between the yoke auxiliary magnetic pole 8 and the magnetic layer of the magnetic recording medium A during recording and reproduction. This is because when reproducing information, there is a possibility that the output due to magnetic flux detection from the yoke auxiliary magnetic pole 8 will be output from the coil 4, so the magnetic flux of information must be detected from the main magnetic pole 3. It's for a reason. In addition, in order to reliably read information from the magnetic recording medium A, a closed magnetic path is configured in the main magnetic pole B so that the detected magnetic flux does not leak to the outside, and in order to reduce reluctance (magnetic resistance), the magnetic recording medium is This is done by increasing the area S of the opposing portions of the 5 yoke auxiliary magnetic poles 8.

To explain the operation of this perpendicular magnetic recording and reproduction, when recording, a current 1 corresponding to the information to be recorded flows through the coil 4 wound around the auxiliary magnetic pole 5, and the thin main magnetic pole 3 The magnetic flux concentrates at the tip of the magnetic axis 1 of the magnetic strip, causing the magnetic strip to form.

Information is recorded by causing magnetization reversal only in the portion of the magnetic layer 6 of the magnetic recording medium A that is in contact with the tip of the magnetic axis 1 of the magnetic recording medium A.

In addition, when reproducing recorded information, magnetic flux is detected at the tip of the magnetic axis 1 of the thin magnetic strip // of the main magnetic pole 6 according to the magnetization of the magnetic layer 6 of the magnetic recording medium A, and a magnetic flux is detected by the magnetoelectric conversion effect. Information is read and reproduced using the current flowing through the coil 4 as an output.

However, in this proposed perpendicular magnetic recording/reproduction method, since the main magnetic pole 6 is always in contact with the magnetic recording medium A, dust etc. accumulates at the tip of the magnetic axis 1 of the main magnetic pole 3, causing recording and reproduction. There were drawbacks that sometimes led to errors.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a perpendicular magnetic recording medium which eliminates the above-mentioned drawbacks and has a means for bringing the main pole into contact with and separating from the magnetic recording medium using air pressure.

The present invention has been made to achieve the above object, and is characterized in that the tip of the magnetic axis is in contact with the surface of the magnetic layer of the magnetic recording medium, and a main magnetic pole, an auxiliary magnetic pole surrounding the main magnetic pole with a fine 71% gear, and a closed magnetic path formed from the auxiliary magnetic pole through the magnetic axis of the main magnetic pole and a magnetic recording medium; It is also known for having a yoke auxiliary magnetic pole provided to create a minute gap with the surface of the magnetic recording medium, a coil wound around the auxiliary magnetic pole, and means for moving the main magnetic pole using air pressure.

Hereinafter, the present invention will be explained in detail with reference to Examples.

FIG. 3 is a diagram showing the configuration of an embodiment of the present invention, in which an air feed unit 9 is disposed at the head of the main magnetic pole 6 shown in FIG. This air feeding unit 9 is
Compressed air Ao i: air reservoir 11 , which is fed and has a compressed air inlet 10 . Air reservoir 12 that presses the main magnetic pole 6
A throttle device 13 is provided between the air reservoir 11 and the air reservoir 12 to adjust the pressure.

For perpendicular magnetic recording and reproduction, the do is located below the magnetic recording medium A, and when not recording or reproducing, it moves downward under the weight of the main magnetic pole 3, and the tip of its main axis It is configured so as not to come into contact with the recording medium A.

When recording information in the perpendicular magnetic recording and reproducing mode of this embodiment, the valve (not shown) of the air tank is opened and compressed air Ao is sent into the air reservoir 11 through the compressed air inlet 10. A device 13 adjusts the pressure in the air reservoir 12 to bring the magnetic axis 1 of the main pole 3 into contact with the magnetic recording medium A at a predetermined pressure.

Next, a current i corresponding to the information to be recorded flows through the coil 4 wound around the auxiliary magnetic pole 5, and as a result, magnetic flux is concentrated at the tip of the magnetic axis 1 of the thin magnetic strip of the main magnetic pole 3, and the magnetic strip Magnetization reversal occurs only in the portion of the magnetic layer 6 of the magnetic recording medium A that is in contact with the tip of the magnetic axis 1, and information is recorded. When reproducing recorded information, magnetic flux is detected at the tip of the magnetic axis 1 of the thin magnetic strip of the main pole 6 according to the magnetization of the magnetic layer 6 of the magnetic recording medium A, and the coil 4 is Information is read out and reproduced using the current flowing through it as output.

FIG. 4 is a diagram showing the configuration of another embodiment of the present invention,
One side of the yoke auxiliary magnetic pole 8 of the embodiment shown in FIG. 3 is removed, and a yoke auxiliary magnetic pole 8' is provided on only one side of the auxiliary magnetic pole 5 so as to form a closed magnetic path to the magnetic recording medium A.

This makes it easier to wind the coil 4 around the auxiliary magnetic pole 5.

FIG. 5 is a diagram showing the structure of an embodiment of the multi-magnetic pole of the present invention, in which a plurality of main magnetic poles 3 are arranged movably in the auxiliary magnetic pole 5 of FIG. It is something that That is, there is a minute gear between the auxiliary magnetic pole 5 and each main magnetic pole 6. Furthermore, a compressed air feeding unit 9 is individually arranged at the head portion of each main magnetic pole 3. A coil 4 is wound around the auxiliary magnetic pole 5, and is configured to be capable of recording and reproducing. Originally, auxiliary magnetic poles were provided individually,
A coil is wound around each of the auxiliary magnetic poles, but if it is multi-pole, it becomes a difficult task, so in this embodiment, only one auxiliary magnetic pole 5 is used and the coil 4 is wound around it. Therefore, manufacturing of the multi-pole head becomes easy. When a current 1 flows through this coil 4, all of the plurality of main magnetic poles 6 are excited, but what is actually recorded on the magnetic recording medium A is the fact that the magnetic axis 1 of the main magnetic pole 6 is connected to the magnetic recording medium A. Only the parts that are in contact. . The selection of the contact main poles 6 is performed by a compressed air feed unit 9 that supplies compressed air to each main pole 3.

The recording/reproducing operation of the embodiment shown in FIGS. 4 and 5 is as follows.
Since it is basically the same as the one shown in the figure, it is omitted here.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and may be modified in any shape without changing the gist thereof.

Of course, the arrangement etc. can be changed.

As explained above, according to the present invention, a main magnetic pole and an auxiliary magnetic pole are combined, a magnetic recording medium is provided on one side of the magnetic recording medium for perpendicular magnetic recording and reproduction, the main magnetic pole and the auxiliary magnetic pole have a special structure, and the main magnetic pole Since a closed magnetic path is formed from the magnetic recording medium to the magnetic recording medium, it is possible to improve the efficiency of magnetic energy when recording and reproducing information, and to improve the S/N ratio during reproduction.

In addition, a compressed air supply unit 7 is placed at the head of the main magnetic pole, and the compressed air is used to press the main magnetic pole only during recording and playback. Good contact with the recording medium can be maintained at all times.
Errors during recording and reproduction can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of conventional perpendicular magnetic recording and reproduction; FIG. 2 is a diagram showing the configuration of perpendicular magnetic recording proposed by the inventors of the present invention; The figure shows the configuration of one embodiment of the present invention, and FIG. 4 shows another embodiment of the present invention.
FIG. 5 is a diagram showing the configuration of an embodiment of the multi-pole head of the present invention. 1 Magnetic axis 2 Protective material 6/main magnetic pole 4 Coil 5 Auxiliary magnetic pole 6 Magnetic layer 7 Pace layer 8.8' Yoke auxiliary magnetic pole S Area of the surface of the yoke auxiliary magnetic pole facing the surface of the magnetic layer of the magnetic recording medium 9 Compressed air Feed 22, 10 Compressed air inlet 11.12 Air reservoir ~ 13 Throttle device

Claims (1)

[Claims] A main magnetic pole whose magnetic axis tip is in contact with the surface of the magnetic layer of the magnetic recording medium and is arranged perpendicular to the surface, and an auxiliary magnetic pole which is provided to surround the main magnetic pole with a small gap in between. , a yoke auxiliary magnetic pole provided to form a closed magnetic path from the auxiliary magnetic pole to the magnetic axis of the main magnetic pole and the magnetic recording medium, and to create a minute gap with the surface of the magnetic recording medium; and a yoke wound around the auxiliary magnetic pole. 1. A perpendicular magnetic recording/reproducing head, comprising: a coil having a magnetic pole; and means for moving the main magnetic pole using air pressure.