JPH0445885B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a perpendicular magnetization type magnetic head, and in particular, to increasing the recording density of a magnetic recording medium,
The present invention relates to a perpendicular magnetization type magnetic head that can simplify the structure of the head in azimuth recording.

[Prior Art] Recently, perpendicular magnetization recording methods have been attracting attention, in which residual magnetization is formed in the thickness direction of a magnetic recording medium and signals are recorded and reproduced on the magnetic recording medium at high density. According to this recording method, the shorter the recording wavelength, the more the magnetic field can be reduced, and it is expected to perform high-density recording with excellent short wavelength characteristics.

FIG. 1 shows a schematic configuration of a single pole SP (Single Pole) head H for perpendicular magnetization recording (hereinafter simply referred to as SP head) employed in this perpendicular magnetization recording method.

As shown in the figure, a main magnetic pole 1 formed in the form of a thin film and made of a magnetic material is provided at the center, and a pair of cores 2 are provided to support it from both sides. The core 2 is made of a magnetic material, contacts one side of the main magnetic pole 1, and holds it in place to reinforce it, and an excitation coil 3 is wound around its outer periphery to excite the main magnetic pole 1. a magnetic excitation core 4 , a magnetic core 5 which serves as the other end of the inflow/outflow end of the magnetic flux flowing in and out of the excited main magnetic pole 1 and has a return action as a function, and these magnetic excitation cores 4 . and a connecting portion 6 that connects the magnetic cores 5 at their respective bottoms.

The conventional SP head H is constructed as described above.
As shown in FIG. 2, the signal is recorded and
Regeneration will take place. In the figure, imaginary lines 8 indicate lines of magnetic force, and when current is applied to the excitation coil 3, it passes through the recording medium 7 and forms a vertical magnetic field concentrated at the tip of the main magnetic pole 1.

FIG. 3 is a plan view showing the positional relationship between the SP head H and the recording medium 7, and the recording medium 7 is intended to be a floppy disk (FDD) for a computer.

In the figure, 9a, 9b, . . . are tracks on which signals are recorded, and since recording and reproduction are generally performed repeatedly on an FDD, as shown in the figure, the SP head H is positioned astride two adjacent tracks 9a, 9b. Such cases can often occur. Note that 10a, 10b... are each track 9.
This is a guard band that separates a, 9b, .

In addition, since the main magnetic pole 1 of the SP head H has its longitudinal direction aligned with the width direction of the tracks 9a, 9b,..., when the SP head H tries to reproduce the signal of the track 9b, When reproducing from a position spanning two tracks 9a and 9b, the signal of the adjacent track 9a is also reproduced at the same time, resulting in a crosstalk condition, which causes an error in the reproduced signal.

On the other hand, the high-density recording capability as an advantage of the perpendicular magnetization recording method is obtained by increasing the recording density (bit density) in the length direction of the tracks 9a, 9b,..., and this advantage can be further expanded. In order to achieve this, it is possible to increase the density (track density) of the tracks 9a, 9b, . . . in the width direction. To this end, it is necessary to reduce the width of the tracks 9a, 9b, . . . and to reduce the width of the guard bands 10a, 10.
It is possible to reduce the width of tracks 9a, 9b, . . . For example, if the width of tracks 9a, 9b, . . . guard band 10
If the widths of a, 10b, .

[Summary of the Invention] The present invention has been devised to effectively solve the above-mentioned problems, and its purpose is to provide a magnetic recording medium having different azimuth angles with respect to the width direction of the tracks. By configuring the two main magnetic poles integrally and alternately selecting the main magnetic poles to correspond to each adjacent track, the azimuth effect is exhibited and the track density is increased, and the two-piece configuration in the conventional azimuth recording method is achieved. An object of the present invention is to provide a perpendicular magnetization type magnetic head which can be made into one magnetic head with a simplified structure.

[Embodiments of the Invention] A preferred embodiment of the perpendicular magnetization type magnetic head according to the present invention will be described below with reference to the accompanying drawings.

FIG. 4 shows a schematic configuration of a perpendicular magnetization type magnetic head according to the present invention, and corresponds to FIG. 1 showing a conventional example.

As shown in the figure, a pair of main magnetic poles 1a and 1b formed in a thin film shape and made of a magnetic material are parallel to each other, and track 9a, 9b, . . .
are provided with an azimuth angle θ equal to opposite positive and negative angles with respect to the width direction. As shown in FIG. 6, each track 9a, 9b,...
There is no guard band in the conventional example, and they are formed adjacent to each other.

Each of the main magnetic poles 1a, 1b is held in place by magnetic excitation cores 4a, 4b, 4c, 4d in contact with both sides thereof, and a current is passed through excitation coils 3a, 3b wound around the outer circumference of the magnetic excitation cores 4a, 4b, 4c, 4d. The main pole excitation elements 11a, 11b are configured to be excited by this.

Among the magnetic excitation cores 4a, 4b,..., the magnetic excitation cores 4b, 4c located inside the main pole excitation elements 11a, 11b are integrally formed with the magnetic core 5 provided in the intermediate part of each other, and They are connected by a connecting part 6 at the bottom.

The magnetic core 5 has each main pole excitation element 11
a, 11b, so that the magnetic fluxes flowing in and out of the main magnetic poles 1a, 1b are equal, and in the width direction of the tracks 9a, 9b,... The structure is such that an equal magnetic flux density can be obtained throughout. That is, as shown in FIG. 5, the distances between the side end surfaces 12 and 13 of each of the main pole excitation elements 11a and 11b facing the magnetic core 5 side and the both side end surfaces 14 and 15 of the magnetic core 5 facing these are equal to each other. , and the respective facing surfaces 12 and 14
13 and 15 are arranged in parallel.

As described above, recording and reproduction of the magnetic recording medium 7 (FDD) is performed by the SP head H in which the two main magnetic poles 1a and 1b are integrally constructed. FIG. 6 shows the recording pattern for each track 9a, 9b, . . . and shows the reproduction state thereof.

Each track 9a, 9b, . . . is provided with a recording/reproducing data signal Sa,
Three types of tracking signals P1, P2, P3, which are sequentially repeated as Sb, Sc, . . . , are multiplexed and recorded. In addition, the data signals Sa, Sb,... are recorded as high frequency signals (short wavelength), and the tracking signals
P1, P2, and P3 are recorded as low frequency signals (long wavelength). The SP head H can be positioned almost on the target track with mechanical precision, and the tracking signals P1, P2, and P3 are recorded as fine adjustment signals. Therefore, the signal Sa+P1 is recorded on the track 9a, the signal Sb+P2, etc. is recorded on the track 9b, and when recording, the signal Sa+P1 is recorded on the track 9b.
The main magnetic poles 1a and 1b are made to correspond alternately to each adjacent track, such that the main magnetic pole 1a corresponds to the main magnetic pole 1a and the main magnetic pole 1b corresponds to the adjacent track 9b. , 3b).

Here, the azimuth effect will be explained. The main magnetic pole has an azimuth angle with respect to the track width direction, and if the azimuth angle matches the angle of the recording pattern of the signal recorded on the track, normal reproduction can be performed, but if they do not match, normal reproduction can be performed. ,
The high frequency region of the reproduced signal is attenuated, and only the signal in the low frequency region is reproduced.

For example, if SP head H is the signal on track 9b,
When Sb+P2 is to be reproduced and a portion thereof overlaps the track 9a as shown in FIG. 6, it is the main pole 1b that is excited. The azimuth angle of the main pole 1b matches the recording pattern of the track 9b, but does not match the recording pattern of the track 9a. Therefore, due to the above-mentioned azimuth effect, the tracking signal P1 which is the low frequency signal of the track 9a, the data signal Sb and the tracking signal P2 of the track 9b are reproduced, and the data signal which is the high frequency signal of the track 9a is reproduced. The signal Sa is attenuated and not reproduced. In other words, it becomes possible to reduce adjacent track interference. Incidentally, the SP head H can constitute a tracking servo circuit (not shown) by reproducing the tracking signals P1 and P2.

Note that the azimuth recording method that uses the azimuth effect is also used in home VTRs, etc., but in this case two recording/playback heads are provided, and configuring two heads at the same time is difficult. In terms of composition,
Since the SP head of the present invention is large in size and difficult to process and install, the single SP head of the present invention is advantageous in this respect.

Furthermore, since the distance from any point on the recording medium 7 of each main magnetic pole 1a, 1b to the magnetic core 5 is set equal across the track width direction, the recording and The reproduction efficiency becomes equal, and the magnetic flux is not concentrated in a specific location, resulting in improved recording and reproduction efficiency.

As shown in FIG. 7, if the distances between the main pole excitation elements 11a and 11b and the magnetic core 5 are equal, the overall magnetic flux or magnetic flux density will be equal, so that the opposing surfaces 12 and 1
Even if 4, 13, and 15 are not parallel, a sufficient effect can be obtained and processing becomes easy.

[Effects of the Invention] As is clear from the above description, the present invention provides the following excellent effects.

That is, two main magnetic poles having different azimuth angles with respect to the width direction of the tracks of the magnetic recording medium are integrally constructed, and the main magnetic poles corresponding to each adjacent track are alternately selected to exhibit the azimuth effect. By doing so, the guard band can be removed and the track density can be increased as much as possible.

Furthermore, the two magnetic heads in the conventional azimuth recording system can be replaced with a single magnetic head with a simplified structure.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a conventional example of a single-sided recording/reproducing SP head for perpendicular magnetization recording, FIG.
4 is a perspective view showing an embodiment of the SP head according to the present invention, and FIG. 5 is a plan view schematic diagram of the SP head shown in FIG. 4. FIG. 6 is an explanatory diagram showing the planar positional relationship between the SP head in FIG. 4 and the recording medium, and FIG. 7 is a planar schematic diagram of another embodiment of the SP head according to the present invention. FIG. 2 is an explanatory diagram showing the configuration. In addition, in the figure, 1a, 1b are main magnetic poles, 4a, 4b,
4c and 4d are magnetic excitation cores, 5 is a magnetic core, 7 is a magnetic recording medium, 9a, 9b, 9c, and 9d are tracks, and 11a and 11b are main pole excitation elements.

Claims (1)

[Claims] 1. A main pole excitation element consisting of a main pole made of a magnetic thin film and a magnetic excitation core that contacts and excites the main pole, each having a different azimuth angle and provided in parallel. A perpendicular magnetization type magnetic head, characterized in that a magnetic core serving as the other inflow/outflow end of the magnetic flux flowing in and out of the main pole excitation element is disposed between the main pole excitation elements. 2. The perpendicular magnetization type magnetic head according to claim 1, wherein the main pole excitation element is arranged at equal positive and negative angles with respect to the track width direction of the magnetic recording medium. 3. The perpendicular magnetization type magnetic head according to claim 1, wherein the magnetic core is provided at an equal distance from each main pole excitation element over the track width.