JPH03241510A - Magnetic head - Google Patents

Abstract

PURPOSE:To prevent the occurrence of pseudo peaks in a reproduced signal waveform by setting the pole end parts positioned on the opposite side of a head gap along a magnetic field generation surface formed by means of the lower surfaces of poles and the head gap to be curved surfaces or polyhedral surfaces. CONSTITUTION:The head gap 3 is formed between the pole 1 and 2 extending from the thin film coil 4 of a magnetic head and parts 100 and 101 where the lower surfaces of the poles 1 and 2 and respective outer parts 6 and 7 cross are chamfered and they are formed so that they continuously curve. When a magnetic recording medium is shifted along a pole face M2 which is thus constituted, the concentration of a magnetic flux is prevented in respective end parts of the pole face M2 by the curve surfaces 10 and 11 formed in respective end parts, and the occurrence of the pseudo peaks P can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention is a technology related to the structure of a magnetic head used in a magnetic disk or the like.

"Prior Art and its Problems" Conventionally, as this type of magnetic head, a thin film magnetic head shown in the front view of FIG. 3(A) and the bottom view of FIG. 3(B) is known.

This magnetic head has a head gap 3 between a first pole l and a second pole 2 extending from a thin film coil (described later) to narrow the spread of the magnetic field, and generates a magnetic field on the lower surface of these poles 2. A pole face M is provided for reading and writing data to and from a magnetic disk (the path shown in the figure), which is a magnetic recording medium.

In FIG. 3(A), the reference numeral 4 is a thin film coil that generates a magnetic field when energized, and the reference numeral 5 is a thin film coil that is levitated from the magnetic disk during rotation. This is a Herad slider for forming a small distance between the magnetic disk and the magnetic head.

In addition, rPIJ shown in FIG. 3(B) is pole 1
"P2" represents the thickness of the pole 2, "rGLJ" represents the size of the head gap 3, and "rTwJ" represents the track width corresponding to the track of the magnetic disk.

``Problems to be Solved by the Invention'' By the way, in the magnetic hennode configured as described above, the pole faces M located on the lower surfaces of the first pole 1 and the second pole 2 are formed in a planar shape. , and the outer portions 6 and 7 of the pole 2, respectively located on opposite sides of the head gap 3, are formed perpendicularly to the lower surface of the pole 2, thereby forming a right angle to both ends of the pole face M. Surfaces 8 and 9 are formed.

On the other hand, the right angle surfaces 8 and 9 formed by the intersection of the lower surfaces of the bolt and the bolt 2, and the outer parts 6 and 7 of these poles 2 are also places where the magnetic field is concentrated, and as a result, as shown in FIG. As shown, when the magnetic recording medium is moved along the pole face M1, a pseudo peak P-P occurs in the waveform of the reproduced signal detected, which further causes the following problems.

(-) If the normal peak receives waveform interference, a peak shift will occur. (d) The normal peak will be removed and the S/N will decrease. (3)
The pseudo peak P-P is part of the shoulder (right angle surfaces 8 and 9)
There was a problem in that the slice level margin was reduced.

This invention was made in view of the above-mentioned circumstances, and prevents the concentration of magnetic flux at the locations where the lower surface of the poled 2 intersects with the outer parts 6 and 7 of the poled 2, thereby causing pseudo peaks. The purpose of the present invention is to provide a magnetic head that prevents the above from occurring.

"Means for Solving the Problem" In order to achieve the above object, in the first invention, a head gap is formed between the poles extending from the coil, and the head gap is formed by the lower surface of the pole and the head gap. A magnetic head in which a magnetic recording medium is moved along a magnetic field generation surface is characterized in that pole ends located on opposite sides of the head gap are curved or polygonal.

In the second invention, a head gap is formed between the poles extending from the coil, and the magnetic recording medium is moved along the magnetic field generating surface formed by the lower surface of the pole and the head gap. , the lower surface of the pole is a flat surface that slopes toward the coil as it moves away from the head gap.

"Function" According to these inventions, the ends of the poles located on opposite sides of the head gap are curved or polygonal, or the lower surface of the pole is a flat surface that slopes toward the coil as it moves away from the head gap. Therefore,
Concentration of magnetic flux is prevented at the portions of the poles located on opposite sides of the head gap.

"Embodiment" An embodiment of the present invention will be described with reference to FIG. 1(A), FIG. 1(B), and FIG. 2.

The basic configuration of the magnetic heads shown in FIGS. 1(A) and 1(B) is the same as that shown in FIGS. 3(A) and 3(B) in "Prior Art". Therefore, the same reference numerals are given to the parts having the same structure, and the explanation thereof will be simplified.

In FIG. 1(A) and FIG. 1(B), reference numerals 10 and 11
What is shown is a curved surface formed on the pole.

These curved surfaces 10 and 11 are formed at each end position of the pole face M, that is, the lower surfaces of the first pole l and the second pole 2, and the respective outer parts 6 and 7 of the pole face M.
(in Fig. 1 (A), the points where
) is chamfered and continuously curved.

The curved surfaces 10 and 11 formed at each end of the pole face M prevent the magnetic flux from concentrating at each end of the pole face M, thereby preventing the occurrence of false peaks. Effects can be obtained.

To explain this situation with reference to FIG. 2, when the magnetic recording medium is moved along the pole face M, it is detected by the curved surfaces 10 and 11 formed at each end of the pole face M. This prevents the generation of pseudo peaks P-P (indicated by dotted lines) in the waveform of the reproduced signal, as in the conventional case.
As a result, (-) normal peaks are prevented from receiving waveform interference, (d) normal peaks are prevented from being shaved off, and S/N can be improved, and (3) pseudo peak P- The superimposition of P is prevented and the slice level margin can be improved.

In this embodiment, the end portions of the poles 2 located on the opposite side of the head gap 3 may be curved surfaces, or may be polygonal surfaces without being limited thereto. P-P is prevented from occurring (corresponding to the first invention).

Furthermore, the present invention is not limited to this, and the lower surface of the poled 2 may be made a flat surface that is inclined toward the coil 4 side as it moves away from the head gap 3, as shown by the dashed line in FIG. 1(A). is prevented from concentrating, and the generation of pseudo peaks P-P as in the prior art is prevented (corresponding to the second invention).

"Effects of the Invention" As explained in detail above, according to these inventions, the ends of the poles located on opposite sides of the head gap are curved or polygonal, or the lower surface of the pole is curved or polygoned as it moves away from the head gap. Therefore, since the plane is inclined toward the coil side, the magnetic flux is prevented from being concentrated in the pole portions located on the opposite side of the head gap, and the effect of preventing the occurrence of pseudo peaks is obtained. .

[Brief explanation of drawings]

1(A) to 2 are diagrams showing one embodiment of the present invention, in which FIG. 1(A) is a front sectional view showing the main part of the magnetic head, and FIG. Pole face M in Figure 1 (A),
FIG. 2 is a diagram showing the waveform of a signal read from the magnetic recording medium when the magnetic recording medium is moved along the pole face M, and FIG. 3 (A) is a bottom view when viewed from below. A front sectional view showing the main parts of a conventional magnetic head, FIG.
) is a bottom view of the pole face M1 seen from below in FIG. 3(A), and FIG. 4 is a signal read from the magnetic recording medium when the magnetic recording medium is moved along the pole face M. FIG. ■...Pole 2...Pole 3...Head gap 4...Thin film coil M,...Pole face

Claims (2)

[Claims] (1) In a magnetic head in which a head gap is formed between poles extending from a coil, and a magnetic recording medium is moved along a magnetic field generation surface formed by the lower surface of the pole and the head gap, the head gap is A magnetic head characterized in that pole ends located on opposite sides of the magnetic head are curved or polygonal. (2) In a magnetic head in which a head gap is formed between poles extending from a coil, and a magnetic recording medium is moved along a magnetic field generation surface formed by the lower surface of the pole and the head gap, A magnetic head characterized in that the lower surface is a flat surface that slopes toward the coil as it moves away from the head gap.