JPS5870413A - Scanning type vertical magnetic head - Google Patents

Abstract

PURPOSE:To increase a relative velocity between a recording medium and a head, by partially varying the magnetic permeability of the ferromagnetic part of a main magnetic pole. CONSTITUTION:An auxiliary magnetic pole 6 is formed by winding an energizing winding 8 round a ferromagnetic material core 7. On the other hand, a main magnetic pole 13 is formed by pinching a ferromagnetic thin film 9 such as permalloy, etc. from both sides by ferromagnetic blocks 10, 10', and making yokes 11, 11' of a ferromagnetic material, to which scanning magnetic field applying windings 12, 12' is wound, press- contact from both ends of the blocks 10, 10'. When a current is made to flow to the windings 12, 12', magnetic fluxes 14, 14' are generated in the blocks 14, 14', by which the thin film 9 is saturated except the center part, and the magnetic permeability drops. As for the center part, the magnetic fluxes 14, 14' negate each other, the magnetic permeability is not varied, and the center part becomes a higher magnetic permeability part than other part. When the auxiliary magnetic pole 6 is energized by a signal current, only the center part of the thin film 9 is magnetized, and a medium 1 is magnetized. The high magnetic permeability part is moved in the width direction by changing a relative value of magnitude of a scanning magnetic field of the yokes 11, 11'.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a scanning perpendicular magnetic head suitable for high-density magnetic recording, and in particular to a scanning perpendicular magnetic head that is a fixed head type but can increase the relative speed between the recording medium and the head. It provides:

The vertical recording method, in which the recording medium is magnetized in the thickness direction, is suitable for high-density recording because, in principle, the shorter the wavelength, the smaller the demagnetizing field within the medium. In order to successfully perform such perpendicular recording, a recording medium having a strong difference Jj l'l in the vertical direction and a recording head that generates a strong perpendicular component magnetic field are required.

A conventional perpendicular recording type magnetic head CI has a basic configuration as shown in FIG. In the magnetic recording medium 1, a perpendicular magnetization film 4 having easy magnetization 11Ql+ in the direction perpendicular to the film surface is formed on -1- of a non-magnetic base 2 through a ferromagnetic thin film 3 such as permalloy having an axis of easy magnetization in the film surface. It is what was done. The magnetic head i (1) consists of a main magnetic pole and an auxiliary magnetic pole 6 having an excitation winding 8.
]: This head is made of a 114-inch structure.Hereinafter, this head will be referred to as an auxiliary magnetic pole excitation type vertical head). Note that the main magnetic pole 5 is set to 1 on the perpendicularly magnetized film 4.

When recording a signal in the auxiliary magnetic pole excitation type vertical head having such a configuration, the ferromagnetic core 7 is magnetized by the signal current flowing through the excitation winding 8, and the magnetic field generated by the ferromagnetic core 7 causes the main magnetic pole to be Magnetize 5. The perpendicularly magnetized film 4 is vertically magnetized by a strong magnetic field generated by the main pole 6.

With such an auxiliary pole-excited vertical head, it is possible to obtain vague recording characteristics2 for perpendicular recording, and furthermore, by using the above-mentioned two-layer film medium as a recording medium, efficient high-density recording is possible. be.

However, in the conventionally proposed auxiliary pole-excited vertical head, the direction of relative movement between the recording medium and the head matches the direction of movement of the recording medium, with the track width in the main pole or the auxiliary pole. The relative speed of was also consistent with the recording medium speed. Therefore, when recording high-bandwidth signals, it is necessary to make the recording medium speed extremely high. Especially when using magnetic tape as a recording medium, it is necessary to have a tape reversing mechanism and a stable tape running system when recording multiple channels with narrow track recording. Extremely advanced technology is required. Further, as a method of obtaining a large relative speed, it is possible to apply a conventional rotary head type, but the above-mentioned opposed vertical head complicates the manufactured equipment, which is difficult to mount, and makes it difficult to reduce the burr.

The present invention was made in order to eliminate the above-mentioned drawbacks of the conventional technology, and is based on a four-node scanning perpendicular magnetic head that achieves a high relative speed despite being an old fixed head type with low recording medium speed←L speed. , 4 servings.

Hereinafter, the scanning type perpendicular magnetic head of the present invention will be explained based on embodiments. 1 ij: A perspective view of a scanning perpendicular magnetic head according to an embodiment of the present invention, and FIG. 3 is a top view of the same.

In these figures, the auxiliary magnetic pole 6 is the same as that described in the conventional example, and has a structure in which an excitation winding 8 is wound around a ferromagnetic core 7. On the other hand, the main magnetic pole 13 has a ferromagnetic thin film 9 made of permalloy or the like sandwiched from both sides by ferromagnetic blocks 10 and 10', and a ferromagnetic film wound with scanning magnetic field application windings 12 and 12' from both ends of tM10y10'. It has a structure in which yokes 11 and 11' made of bodies are brought into contact with each other. The magnetic recording medium 1 is driven in the direction iA between the main magnetic pole 13 and the auxiliary magnetic pole ieO.

Next, the operation of the scanning perpendicular magnetic head having the above configuration will be explained. When a current is passed through the windings 12 and 12' so that a magnetic flux as shown by the arrow is generated in the scanning magnetic field applying yokes 11 and 11', if the current magnitudes are the same, the magnetic flux in the blocks 10 and 1o' will be as shown by the arrow 14. 14'. The ferromagnetic thin film 91 sandwiched between the blocks 10 and 10' is saturated and its magnetic permeability decreases in areas other than the central part due to the scanning magnetic fluxes j 4 and 14', but in the central part, the scanning magnetic fluxes 14 and 14'
are equal in size and opposite in direction, the magnetic fluxes cancel each other out and become almost zero, so their magnetic permeability does not change. Therefore, only this central portion has higher magnetic permeability than other portions. At this time, if the auxiliary magnetic pole 6 is excited by the signal current, only the high permeability portion of the intermediate part of the ferromagnetic thin film 9 in the main magnetic pole 13 is magnetized in accordance with the signal magnetic field, and the recording medium 1 is also magnetized at the same time. The high permeability portion of the ferromagnetic thin film 9 moves in the width direction of the main pole 13 by changing the relative magnitude of the scanning magnetic field of the yokes 11, 11'.

Therefore, when a signal type Ilf is applied to the excitation winding 8 while moving this high magnetic permeability portion in the direction of the magnetic pole 13 rl-1, a recording pattern 15 as shown in FIG. 4 as an example is formed on the recording medium. Can be formed.

In the case of reproduction, only the high permeability portion of the ferromagnetic thin film 9 generated by the scanning magnetic field changes its direction of magnetization in accordance with the magnetization of the recording medium, so that changes in the magnetic flux can be detected by the winding 8 of the auxiliary magnetic pole.

FIG. 5 shows another embodiment of the scanning vertical head of the present invention. As shown in the figure, slits are made by photoetching in the main magnet and the 1if130 ferromagnetic thin film 9, so that the magnetically saturated portion and the unsaturated portion are separated from each other. Saturated areas are clearly distinguished and crosstalk is reduced.

As can be seen from the above description, according to the scanning vertical head of the present invention, the relative movement speed between the head and the medium is not uniquely determined by the medium movement speed alone.

Since the scanning magnetic field in the main pole 13 can be changed by J2, high frequency signals can be recorded and reproduced without increasing the medium moving speed. Furthermore, since the moving direction of the medium and the recording direction of the signal can be changed, it is possible to perform narrow track recording on the entire surface of the recording medium using the 91-head without the need for moving parts as in the rotary head system.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of a conventional perpendicular magnetic head. FIG. 2 is a perspective view of a scanning perpendicular magnetic head according to an embodiment of the present invention, FIG. 3 is a top view of the magnetic head, FIG. 4 is a diagram showing a recording pattern on a medium by the magnetic head, and FIG. The figure is a top view of a scanning perpendicular magnetic head in another embodiment of the present invention. 6. Auxiliary magnetic pole, 7...Ferromagnetic core, 8-...
・Excitation 1゛1 mushroom winding, 9... Ferromagnetic film, 10.10
'... Block, 11.11'... Yoke for applying scanning magnetic field, 12, 12'... Winding, 13...
...Main magnetic pole. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 0 size can 57

Claims (2)

[Claims] (1) The main magnetic pole placed on the first side of the recording medium, and the auxiliary magnetic pole placed on the other main side of the recording medium (Il+, where the excitation coil is wound overlappingly), A scanning perpendicular magnetic head characterized in that the magnetic permeability of the ferromagnetic member is partially varied by partially magnetically saturating the ferromagnetic member. (2)! ; The magnetic pole is a ferromagnetic thin film sandwiched between ferromagnetic materials, and a yoke around which coils are wound, which are installed on both ends of the ferromagnetic thin film and excite the ferromagnetic thin films from different main surfaces. A scanning perpendicular magnetic head according to claim 1, characterized in that the scanning perpendicular magnetic head comprises: