JP2001028105A - Magnetic head - Google Patents

Abstract

(57) [Problem] To provide a magnetic head which can completely prevent side erasure, has good recording efficiency, and has a high yield. A magnetic head (10) comprising magnetic cores (11a, 11b) having a sliding surface (10A) in which a magnetic gap (g) is formed, and recording and reproducing information signals on a magnetic recording medium sliding on the sliding surface. A groove 16 is provided on the sliding surface so as to be parallel to the sliding direction of the magnetic recording medium and to be in contact with one end of the magnetic gap.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head for recording and reproducing information signals such as audio signals, video signals, and data signals on a magnetic recording medium.

[0002]

2. Description of the Related Art Conventionally, a video tape recorder (VTR), a digital audio tape recorder (DAT), or a digital data recording / reproducing apparatus using a magnetic tape or the like as a magnetic recording medium is mounted on a recording track of a magnetic tape or the like. A magnetic head is provided for writing an information signal as a magnetic signal or reading an information signal recorded on a recording track as a magnetic signal.

This magnetic head is composed of a magnetic core and members such as windings wound around the magnetic core, and a magnetic gap, which is a minute gap, is formed in the magnetic core. The winding functions to transmit an information signal for recording or reproduction as a magnetic flux. The magnetic core functions as a path for transmitting magnetic flux from the winding to the magnetic recording medium during recording and from the magnetic recording medium to the winding during reproduction. The magnetic gap has a function of narrowing the range of the magnetic field spread to the magnetic recording medium during recording and a function of incorporating magnetic flux from the magnetic recording medium during reproduction.

[0004] In recent years, for the purpose of improving the image quality of an image or the like, or increasing the storage capacity, a high-density magnetic recording system capable of recording and reproducing more information signals by shortening the wavelength of the information signal. A recording method is adopted. For this reason, high coercive force magnetism such as a metal tape in which a ferromagnetic metal powder is applied on a base film as a magnetic powder used for a magnetic layer of a magnetic recording medium or a vapor deposition tape in which a ferromagnetic metal material is directly deposited on a base film. A recording medium is being used.

[0005] In order to record and reproduce information signals on and from such a high coercive force magnetic recording medium, a metallic magnetic material having a high magnetic permeability and a high saturation magnetic flux density, for example, an iron-based alloy or an iron-based magnetic material. A laminated magnetic head having a magnetic core made of a nickel alloy, an iron-cobalt alloy, or the like, or a ferrite magnetic head having a magnetic core made of, for example, MnZn ferrite, or a magnetic core made of, for example, MnZn ferrite, and having a high magnetic permeability MIG (metal-in-gap) type magnetic heads in which a metal-based magnetic layer having a high saturation magnetic flux density is disposed in a magnetic gap are used.

FIG. 11A is a perspective view showing an example of a conventional MIG type magnetic head, and FIG. 11B is an enlarged plan view of a sliding surface thereof. The MIG type magnetic head 20 has two magnetic core halves 21a and 21b abutted to each other via a gap material and joined and integrated by glass fusion or the like.
It is composed of A sliding surface 20A on which the high coercive force magnetic recording medium slides between the joining surfaces of the magnetic core halves 21a and 21b.
A magnetic gap g for generating a magnetic flux for recording / reproducing an information signal to / from a high coercive force magnetic recording medium is defined closer to the magnetic gap g.

[0007] Track width regulating grooves 22a and 22b for regulating the track width Tw of the magnetic gap g are formed on the joining surface of the magnetic core halves 21a and 21b.
The metal magnetic thin films 23a and 23b are formed on the joining surfaces of the magnetic core halves 21a and 21b and on the inner surfaces of the track width regulating grooves 22a and 22b, respectively, in the shape of an arc extending from the vicinity of the both end edges in the depth direction. Is filmed. Further, the joining surface of each of the magnetic core halves 21a and 21b has a winding groove 2 for regulating the depth of the magnetic gap g and passing the winding.
4a, 24b are formed, and winding guide grooves 25a, 2
5b are formed.

[0008]

SUMMARY OF THE INVENTION The above-mentioned conventional MIG
Type magnetic head 20, each magnetic core half 21a, 21b
When joining, the recording tracks may be displaced, or the metal magnetic thin films 23a and 23b may sag at the gap ends. When an information signal is recorded by using the MIG type magnetic head 20 in a state where these deviations and sags have occurred, there is a problem that an unnecessary leakage magnetic field is generated from a track edge and a recording pattern is disturbed. In particular, the recording method of the information signal is as shown in FIG.
In the case of the overwriting recording method as shown in FIG. 5, the S / N of the recording by the so-called side erase is reduced, and all the recording tracks cannot be used effectively.

On the other hand, as shown in FIG. 12, after joining the joining surfaces of the magnetic core halves 31a and 31b, the track width regulating grooves 32a and 32b are reworked from the side surface side to eliminate the deviation of the recording tracks. And a magnetic head 30 having a clear track edge has been proposed (JP-A-8-1856).
No. 06). According to the magnetic head 30 having such a configuration, side erasing can be reduced, but since the magnetic core near the magnetic gap g is not parallel to the recording track, the side erasing is completely prevented by the leakage magnetic field from the edge of the magnetic core. It cannot be prevented. Further, since all of the metal magnetic thin films 33a and 33b near the magnetic gap g are removed, the recording efficiency is significantly deteriorated. Furthermore, a track width T of about 10 μm, which is indispensable especially for high-density recording.
In the case of w, the probability that the recording track is damaged is high, and the yield is very poor.

As shown in FIG. 13, after joining the joining surfaces of the magnetic core halves 41a and 41b, the vicinity of the contact between the track width regulating grooves 42a and 42b and the magnetic gap g is removed from the upper surface side by laser processing. In addition, a magnetic head 40 in which a recording track is not displaced has been proposed (Japanese Patent Laid-Open No.
-353607). In the magnetic head 40 having such a configuration, the magnetic core near the magnetic gap g is not parallel to the recording track, similarly to the magnetic head 30 shown in FIG. 12, so that the side erase is completely prevented by the leakage magnetic field from the edge of the magnetic core. Can not do it.

Further, as shown in FIG. 14, after joining the joining surfaces of the magnetic core halves 51a and 51b, two grooves 56a and 56b contacting both ends of the magnetic gap g from the upper surface side.
A magnetic head 50 has been proposed which eliminates the deviation of the recording tracks and clarifies the track edges (see Japanese Unexamined Patent Publication No. 1-235012). According to the magnetic head 50 having such a configuration, the side erasing can be completely prevented, but the metal magnetic thin films 53a and 53b near the magnetic gap g are removed, so that the recording efficiency is significantly deteriorated. In addition, 1 is essential especially for high-density recording.
When the track width Tw is about 0 μm, there is a high probability that the recording track will be damaged, and the yield is very poor. Further, as described in JP-A-2-240806, in a magnetic head in which the glass is not filled in the groove, a clear magnetic property is generated due to a change in shape such as chipping of a track edge or dripping during running of the magnetic tape. It becomes difficult to maintain the recording pattern, and clogging by magnetic tape powder occurs.

The present invention has been made in view of the above circumstances, and provides a magnetic head which can completely prevent side erasure, has good recording efficiency, has high tape running reliability, and has a high yield. The purpose is to do.

[0013]

According to the present invention, there is provided a magnetic recording medium comprising a magnetic core having a sliding surface on which a magnetic gap is formed, wherein the magnetic recording medium slides on the sliding surface. On the other hand, in a magnetic head for recording and reproducing information signals,
This is achieved by providing a groove provided on the sliding surface so as to be parallel to the sliding direction of the magnetic recording medium and to be in contact with one end of the magnetic gap.

According to the above configuration, particularly in the overwrite recording method, the deviation of the end of the magnetic gap can be completely eliminated, and the magnetic core near the end of the magnetic gap is made parallel to the recording track. Therefore, it is possible to prevent side erasure that disturbs the overwritten recording track. At this time, since the magnetic core is left on the side where no groove is formed, a decrease in recording efficiency due to a reduction in the core volume can be minimized. Further, by filling the groove with a non-magnetic material, clogging of the magnetic tape powder into the groove and chipping of the track edge due to the running of the magnetic tape can be prevented.

[0015]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Note that the embodiments described below are preferred specific examples of the present invention, and therefore, various technically preferable limitations are added. However, the scope of the present invention is not limited to the following description in the following description. It is not limited to these forms unless otherwise stated.

FIG. 1A is a perspective view showing an example of a MIG type magnetic head which is an embodiment of the magnetic head of the present invention, and FIG. 1B is an enlarged plan view of a sliding surface thereof. The magnetic head 10 is composed of two magnetic core halves 11a and 11b which are abutted to each other via a gap material and are joined and integrated by low-temperature thermal diffusion bonding or the like by glass fusion or thermal diffusion of noble metals. . Each magnetic core half 1
A magnetic gap g for generating a magnetic flux for recording and reproducing an information signal with respect to the high coercive force magnetic recording medium is provided near the sliding surface 10A on which the high coercive force magnetic recording medium slides between the joining surfaces 1a and 11b. Is defined.

As a characteristic part of the present invention, a linear one piece parallel to the sliding direction of the high coercive force magnetic recording medium and in contact with one end of the magnetic gap g is provided on the sliding surface 10A. Groove 16 is provided. Due to the groove 16, each of the magnetic core halves 11a and 11b near the magnetic gap g becomes
It is regulated substantially parallel to the sliding direction of the high coercive force magnetic recording medium. Note that the groove 16 is arranged on the side on which the information signal is overwritten when the information signal recording method is the overwrite recording method.

Each of the magnetic core halves 11a and 11b is made of an oxide soft magnetic material such as Mn-Zn ferrite or Ni-Zn ferrite.
On the joint surface b, track width regulating grooves 12a and 12b for regulating the track width Tw of the magnetic gap g are formed in an arc shape from the vicinity of both ends of the magnetic gap g in the depth direction, respectively. Metal magnetic thin films 13a and 13b are formed on the joining surfaces of the halves 11a and 11b and on the inner surfaces of the track width regulating grooves 12a and 12b. And
Each track width regulating groove 12a, 12b is filled with a non-magnetic material, for example, glass.

Further, winding grooves 14a and 14b for restricting the depth of the magnetic gap g and for passing the winding are formed on the joining surfaces of the respective magnetic core halves 11a and 11b so as to have a substantially rectangular side surface. A winding guide groove 15a, 1
5b has a substantially rectangular side surface.
The winding grooves 14a and 14b may be formed only on one of the bases.

Here, the metal magnetic thin films 13a and 13b are
For example, each magnetic core half 11 is made of a ferromagnetic metal material such as an iron-based alloy, an iron-nickel-based alloy, and an iron-cobalt-based alloy.
Films are formed on the entire surface including the joint surfaces a and 11b and the insides of the winding grooves 14a and 14b. The metal magnetic thin films 13a, 1
As the ferromagnetic metal material 3b, for example, a ferromagnetic alloy material having a high saturation magnetic flux density and excellent soft magnetic properties is used. Any known material, whether amorphous or not, can be used.

As the ferromagnetic crystalline alloy, for example, FeA
1Si alloy, FeNiAlSi alloy, FeGaSi
Alloy, FeAlGe alloy, FeGaGe alloy, F
eSiCo-based alloy, FeSiGaRu-based alloy, FeCo
SiAl alloys and the like can be mentioned. Further, in order to further improve the corrosion resistance and wear resistance, Co, Ti, Cr, N
b, Mo, Ta, Ru, Au, Pd, N, C, O, M
n, Zr, W, Os, Rh, Ir, Re, Ni, Pt,
At least one of Hf, V and the like may be added at 8 atomic% or less. In addition, Co, Fe are mainly Ni,
Zr, Ta, Hf, Mo, Nb, Si, Al, B, G
a, Ge, Cu, Sn, Ru, B, and the like; and a microcrystalline material formed by adding one or more of N, C, and O.

Examples of the ferromagnetic amorphous alloy include a so-called amorphous alloy, for example, an alloy composed of one or more elements of Fe, Ni, and Co and one or more elements of P, C, B, and Si. Zr, Ta, Ti, Hf, M
o, Nb, Au, Pd, Ru, Al, Ge, Be, S
Metals such as alloys containing n, In, W, Mn, Cr, etc.
Metalloid amorphous alloy, or Co, Hf,
A metal-metal-based amorphous alloy containing a transition element such as Zr, a rare earth element, or the like as a main component may be used.

Further, the metal magnetic thin films 13a and 13b
For the purpose of improving the head efficiency, a film may be formed via an insulator film. As the edge film, for example, SiO ₂ ,
Electrical insulating materials such as oxides and nitrides such as AlO ₃ and SiN ₄ can be used. As a method of forming the metal magnetic thin films 13a and 13b, a vacuum thin film forming technique represented by a sputtering method, a vacuum deposition method, an ion plating method, an ion beam method, or the like using an apparatus having excellent controllability of the film thickness is employed. The metal magnetic thin films 13a and 13b are
Films may be formed on at least a part of the surfaces a and b.

FIG. 2A is a perspective view showing an example of a MIG type magnetic head which is another embodiment of the magnetic head of the present invention, and FIG. 2B is an enlarged plan view of a sliding surface thereof. 1, the same components as those in FIG. This magnetic head 10 'is basically the same as the magnetic head 1 of FIG.
0, but has a single linear groove 16 'parallel to the sliding direction of the high coercive force magnetic recording medium provided on the sliding surface 10A and in contact with one end of the magnetic gap g. The configuration is different in that a non-magnetic material, for example, glass is filled therein. By filling the groove 16 ′ with a non-magnetic material in this way, clogging with magnetic powder from a high coercive force magnetic recording medium, chipping of the track edge portion of the groove 16 ′ and sagging can be prevented. The reliability of the magnetic head 10 'during traveling of the magnetic recording medium can be improved.

According to the magnetic heads 10 and 10 'provided with the grooves 16 and 16' having the above-described configuration, it is possible to completely eliminate the deviation of the end of the magnetic gap g, particularly in the overwrite recording system. In addition, since each of the magnetic core halves 11a and 11b near the end of the magnetic gap g can be made parallel to the recording track, it is possible to prevent side erasing that disturbs the overwritten recording track. Therefore, particularly when recording with a narrow track width, which is important for high-density recording, is required, recording can be effectively performed over the entire width of the recording track, so that the S / N of the recording signal can be increased.

Since the grooves 16 and 16 'are formed only at one end of the magnetic gap g, the metal magnetic thin film 13
a and 13b can be configured to be continuous with the effective track. Therefore, compared to the conventional magnetic head 20 in which the grooves 16 and 16 'are not formed, the reduction in the recording efficiency due to the decrease in the core volume near the magnetic gap g can be minimized. Also, the track width regulating groove 32a,
Magnetic head 30 and grooves 56a, 56b
Can be improved in recording efficiency as compared with the conventional magnetic head 50 formed at both ends of the magnetic gap g.
Further, by filling the groove 16 with a non-magnetic material such as glass as shown in the drawing, the reliability of the high coercive force magnetic recording medium during running can be improved. Also, the grooves 16, 16 '
Is formed only on one end side of the magnetic gap g, and the remaining base material increases, so that the recording track is hardly damaged and the yield can be increased.

A method of manufacturing the magnetic head 10 shown in FIG. 1 will be described with reference to FIGS. First, for example, Mn- having a length of about 34.5 mm, a width of about 2.5 mm, and a thickness of about 1 mm.
Two magnetic core half blocks 11 to be magnetic core halves 11a and 11b made of Zn-based ferrite oxide soft magnetic material
Is manufactured by grinding with grinding water. Subsequently, the magnetic gap g is set in the longitudinal direction of each magnetic core half block 11.
The grooves 14 serving as winding grooves 14a and 14b for winding windings are formed by grinding using grinding water (see FIG. 3).

Next, grooves 12 serving as track width regulating grooves 12a and 12b are formed in the short direction of each magnetic core half block 11 by grinding with grinding water. Then, after the groove forming surface of each magnetic core half-block 11 is mirror-polished by polishing so that the surface roughness becomes about 20 ° to 100 °, metal magnetic thin films 13a and 13b of an iron-based alloy are formed by sputtering. Then, a gap material is formed (see FIG. 4).

Next, the respective magnetic core half-blocks 11 are abutted with each other and bonded and integrated by glass fusion to obtain the magnetic core block 1. Thereby, a magnetic gap g is formed. Then, the notch 6 which becomes a linear groove 16 in contact with one end of the magnetic gap g in the transverse direction of the magnetic core block 1 is formed by grinding with grinding water, and the magnetic gap g is set to a predetermined track width Tw. Regulate (see FIG. 5).

Next, the surface on which the magnetic gap g of the magnetic core block 1 is formed is wrapped by cylindrical grinding with a curvature up to a predetermined depth to obtain a sliding surface 10A. The winding guide groove 1 extends in the longitudinal direction of the magnetic core block 1.
The grooves 15a and 15b are formed by grinding using grinding water, and cut by cutting to form the MIG magnetic head 10 (see FIG. 6).

When manufacturing the magnetic head 10 'shown in FIG. 2, the steps shown in FIGS. 3 and 4 are performed in the same manner. Then, the respective magnetic core half-blocks 11 are abutted with each other and bonded and integrated by glass fusion to obtain the magnetic core block 1. Thereby, a magnetic gap g is formed. Then, a notch 6 'which is a linear groove 16' in contact with one end of the magnetic gap g in the lateral direction of the magnetic core block 1 is formed by grinding using grinding water, and the magnetic gap g is set to a predetermined track width. Restrict to Tw. Then, the notch 6 'is filled with glass (see FIG. 7).

Next, the surface on which the magnetic gap g of the magnetic core block 1 is formed is wrapped by cylindrical grinding with a curvature up to a predetermined depth to obtain a sliding surface 10A. The winding guide groove 1 extends in the longitudinal direction of the magnetic core block 1.
The grooves 15a and 15b are formed by grindstone processing using grinding water, and are cut by cutting to form the MIG magnetic head 10 '(see FIG. 8).

FIG. 16 shows the magnetic head 10 of this embodiment shown in FIG. 1, the conventional magnetic head 20 shown in FIG.
4 shows the recording characteristics of the conventional magnetic head 50 (20 MHz).
FIG. 7 is a diagram showing an example of comparison of z), in which the vertical axis represents relative output (dBm) and the horizontal axis represents recording current (mAp-p). This shows the characteristics of the recording efficiency with respect to the recording current. The faster the rise of the relative output with respect to the increase in the recording current, the better the magnetic head. As is apparent from the drawing, the magnetic head 10 of the present embodiment has substantially the same recording efficiency as the recording characteristics of the conventional magnetic head 20 having a high relative output at a low recording current. The magnetic head 10 is a magnetic head having characteristics clearly superior in recording efficiency to the recording characteristics of the conventional magnetic head 50.

By the way, generally, in the overwriting recording, an azimuth recording method is often adopted in order to suppress crosstalk between adjacent tracks. In order to make the magnetic head compatible with the azimuth recording method, a linear groove 16 contacting one end of the magnetic gap g in the lateral direction of the magnetic core block 1 in the process shown in FIG. A notch 6 is formed. That is, as shown in FIG. 17, a notch 66 inclined by the azimuth angle is formed so as to be in contact with one end of the magnetic gap g in the short direction of the magnetic core block 61 and is parallel to the notch 66 (dashed lines A to H). ) To form a magnetic head 60 having a sliding surface 60A having a magnetic gap g with an azimuth angle α as shown in FIG.

However, as shown in FIG. 17, the track width restricting grooves 62a, 6b formed in the magnetic core block 61.
Since the angle of the groove 62 corresponding to the groove 2b with respect to the gap surface is symmetrical, as shown in FIG.
| Θ1−θ2 | = angle between angles θ1 and θ2 of the surfaces constituting the surfaces 2a and 62b with respect to the sliding direction of the high coercive force magnetic recording medium.
This results in a difference of 2α, and one angle θ1 is smaller than the other angle θ2. For this reason, one magnetic core half 6
The recording efficiency and the recording efficiency of a magnetic head having a large azimuth angle in order to increase the recording density, particularly a MIG type magnetic head having an azimuth angle α of 15 degrees or more, have a volume 1b significantly smaller than the volume of the other magnetic core half 61a. This leads to lower levels.

Therefore, as shown in FIG. 19, the track width regulating grooves 112a formed in the magnetic core block 111,
The angle of the groove 112b with respect to the gap surface is adjusted in advance. That is, the track width regulating grooves 112a, 112
The groove 112 is formed on the gap surface of the groove 112 such that the angles θ1 and θ2 have desired values such that a large difference does not occur between the angles θ1 and θ2 of the surface constituting b with respect to the sliding direction of the high coercive force magnetic recording medium. Adjust the angle.

Using such a magnetic core block 111, a notch 116 inclined by the azimuth angle is formed so as to be in contact with one end of the magnetic gap g in the short direction, and is parallel to the notch 116 (dashed lines A to F). 9 has a magnetic gap g having an azimuth angle α as shown in FIG. 9 and has no significant difference between the angles θ1 and θ2 with respect to the sliding direction of the high coercive force magnetic recording medium. Sliding surface 1 having surfaces forming grooves 112a and 112b
A magnetic head 110 having 10A can be provided.
Therefore, this magnetic head 110 basically has the configuration shown in FIGS.
It can be manufactured by the process shown in FIG. In addition, clogging by magnetic powder from a high coercive force magnetic recording medium and
In order to prevent chipping and surface sagging of the track edge portion of No. 6, a magnetic head 110 'having a groove 116' filled with a non-magnetic material as shown in FIG.

FIG. 20 is a diagram showing an example of comparing the recording characteristics (20 MHz) of the magnetic head with the angle θ1 changed. The vertical axis indicates the relative output (dBm), and the horizontal axis indicates the recording current (mA).
pp) are represented. This indicates the characteristics of the recording efficiency with respect to the recording current.
The faster the rise of the relative output, the better the magnetic head. Each magnetic head was a recording magnetic head having an azimuth angle α of 20 degrees, and was prepared by changing the angle θ1 to 50 degrees and changing the angle θ1 to 10, 30 and 50 degrees. Note that R
A normal MIG head having no groove 116 was also prepared as ef. Among these, as is clear from the figure, the magnetic head 110 with the angle θ1 set to 30 degrees and 50 degrees.
Indicates the recording efficiency of a normal MIG head having a high relative output at a low recording current, and a recording efficiency substantially equal to that of a normal MIG head. By setting the angle θ1 to 30 degrees or more in this way, it is possible to prevent substantial deterioration of the recording efficiency.

[0039]

As described above, according to the present invention, side erasure can be completely prevented without impairing recording efficiency and yield, and a highly reliable magnetic head can be supplied.

[Brief description of the drawings]

FIG. 1 is a perspective view and an enlarged plan view showing a first embodiment of a magnetic head of the present invention.

FIG. 2 is a perspective view and an enlarged plan view showing a second embodiment of the magnetic head of the present invention.

FIG. 3 is a first view showing a method for manufacturing the magnetic head of FIG. 1;

FIG. 4 is a second view showing the method for manufacturing the magnetic head of FIG. 1;

FIG. 5 is a third view showing the method of manufacturing the magnetic head of FIG. 1;

FIG. 6 is a fourth diagram showing the method of manufacturing the magnetic head of FIG. 1;

FIG. 7 is a first view showing a method for manufacturing the magnetic head of FIG. 2;

FIG. 8 is a second view showing the method of manufacturing the magnetic head of FIG. 2;

FIG. 9 is a perspective view and an enlarged plan view showing a third embodiment of the magnetic head of the present invention.

FIG. 10 is a perspective view and an enlarged plan view showing a fourth embodiment of the magnetic head of the present invention.

FIG. 11 is a perspective view and an enlarged plan view showing a first example of a conventional magnetic head.

FIG. 12 is a perspective view and an enlarged plan view showing a second example of the conventional magnetic head.

FIG. 13 is a perspective view and an enlarged plan view showing a third example of a conventional magnetic head.

FIG. 14 is a perspective view and an enlarged plan view showing a fourth example of a conventional magnetic head.

FIG. 15 is a view for explaining a general overwrite recording method.

FIG. 16 is a view showing recording characteristics of the magnetic head of FIGS. 1, 9 and 12;

FIG. 17 is a first plan view for explaining a problem when a magnetic head having an azimuth angle is manufactured.

FIG. 18 is a second plan view for explaining a problem in manufacturing a magnetic head having an azimuth angle.

FIG. 19 is a plan view for explaining a method of manufacturing a magnetic head having an azimuth angle that solves the problem shown in FIG. 18;

FIG. 20 is a view showing an example in which recording characteristics of a magnetic head in which an angle θ1 is changed are compared.

[Explanation of symbols]

10, 10 ', 100, 100' ... magnetic head, 1
1a, 11b, 111a, 111b: half magnetic core, 12a, 12a, 112a, 112a: track width regulating groove, 13a, 13a, 113a, 113a,...
.Metal magnetic thin films, 14a, 14b, 114a, 114b
... Winding grooves, 15a, 15b, 115a, 115b
..Winding guide grooves, 16, 16 ', 116, 116'
··groove

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] September 5, 2000 (2009.5)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction contents]

On the other hand, as shown in FIG. 12, after joining the joining surfaces of the magnetic core halves 31a and 31b, the track width regulating grooves 32a and 32b are reworked from the side surface side to eliminate the deviation of the recording tracks. And a magnetic head 30 having a clear track edge has been proposed (JP-A-8-1856).
No. 06). According to the magnetic head 30 having such a configuration, side erasing can be reduced, but since the magnetic core near the magnetic gap g is not parallel to the recording track, the side erasing is completely prevented by the leakage magnetic field from the edge of the magnetic core. It cannot be prevented. Further, since all of the metal magnetic thin films 33a and 33b near the magnetic gap g are removed, the recording efficiency is significantly deteriorated. Furthermore, a track width T of about 10 μm, which is indispensable especially for high-density recording.
In the case of w high probability of recording track is damaged, the yield is very bad.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction contents]

Further, as shown in FIG. 14, after joining the joining surfaces of the magnetic core halves 51a and 51b, two grooves 56a and 56b contacting both ends of the magnetic gap g from the upper surface side.
A magnetic head 50 has been proposed which eliminates the deviation of the recording tracks and clarifies the track edges (see Japanese Unexamined Patent Publication No. 1-235012). According to the magnetic head 50 having such a configuration, the side erasing can be completely prevented, but the metal magnetic thin films 53a and 53b near the magnetic gap g are removed, so that the recording efficiency is significantly deteriorated. In addition, 1 is essential especially for high-density recording.
If 0μm of the front and rear track width Tw high probability that a recording track is damaged, the yield is very bad. Further, as described in Japanese Patent Application Laid-Open No. 2-240806, in a magnetic head in which glass is not filled in a groove, a distinct magnetic property is caused by a change in shape such as chipping of a track edge or dripping during running of a magnetic tape. It becomes difficult to maintain the recording pattern, and clogging by magnetic tape powder occurs.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0023

[Correction method] Change

[Correction contents]

Further, the metal magnetic thin films 13a and 13b
For the purpose of improving the head efficiency, a film may be formed via an insulator film. As the edge film, for example, SiO ₂ ,
Electrical insulating materials such as oxides and nitrides such as Al ₂ O ₃ and SiN ₄ can be used. As a method for forming the metal magnetic thin films 13a and 13b, a vacuum thin film forming technique represented by a sputtering method, a vacuum deposition method, an ion plating method, an ion beam method, or the like using an apparatus having excellent controllability of the film thickness is employed. The metal magnetic thin films 13a and 13b are
Films may be formed on at least a part of the surfaces a and b.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0024

[Correction method] Change

[Correction contents]

FIG. 2A is a perspective view showing an example of a MIG type magnetic head which is another embodiment of the magnetic head of the present invention, and FIG. 2B is an enlarged plan view of a sliding surface thereof. , 1 the same configuration 箇 plants will be omitted with denoted by the same reference numerals. This magnetic head 10 'is basically the same as the magnetic head 1 of FIG.
0, but has a single linear groove 16 'parallel to the sliding direction of the high coercive force magnetic recording medium provided on the sliding surface 10A and in contact with one end of the magnetic gap g. The structure is different in that a non-magnetic material, for example, glass is filled therein. By filling the groove 16 ′ with a non-magnetic material in this way, clogging with magnetic powder from a high coercive force magnetic recording medium, chipping of the track edge portion of the groove 16 ′ and sagging can be prevented. The reliability of the magnetic head 10 'during traveling of the magnetic recording medium can be improved.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0028

[Correction method] Change

[Correction contents]

Next, grooves 12 serving as track width regulating grooves 12a and 12b are formed in the short direction of each magnetic core half block 11 by grinding with grinding water. Then, a gap abutment in which a groove of each magnetic core half block 11 is formed
The surface to be the contact surface is polished to have a surface roughness of 20 ° to 1 °.
After mirror polishing to about 00 °, metal magnetic thin films 13a and 13b of an iron-based alloy are formed by a sputtering method, and then a gap material is formed (see FIG. 4).

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] FIG.

[Correction method] Change

[Correction contents]

FIG. 16 is a view showing recording characteristics of the magnetic head of FIGS . 1, 11 and 14 ;

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] Explanation of sign

[Correction method] Change

[Correction contents]

[Description of References] 10, 10 ', 110 , 110' ... magnetic head, 1
1a, 11b, 111a, 111b: half of magnetic core, 12a, 12b, 112a, 112b: track width regulating groove, 13a, 13b, 113a, 113b ,.
.Metal magnetic thin films, 14a, 14b, 114a, 114b
... Winding grooves, 15a, 15b, 115a, 115b
..Winding guide grooves, 16, 16 ', 116, 116'
··groove

[Procedure amendment 8]

[Document name to be amended] Drawing

[Correction target item name] Figure 2

[Correction method] Change

[Correction contents]

FIG. 2

[Procedure amendment 9]

[Document name to be amended] Drawing

[Correction target item name] Fig. 4

[Correction method] Change

[Correction contents]

FIG. 4

[Procedure amendment 10]

[Document name to be amended] Drawing

[Correction target item name] Fig. 9

[Correction method] Change

[Correction contents]

FIG. 9

[Procedure amendment 11]

[Document name to be amended] Drawing

[Correction target item name] FIG.

[Correction method] Change

[Correction contents]

FIG. 10

[Procedure amendment 12]

[Document name to be amended] Drawing

[Correction target item name] FIG.

[Correction method] Change

[Correction contents]

FIG.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kaoru Aoki 6-7-35 Kita-Shinagawa, Shinagawa-ku, Tokyo Inside Sony Corporation (72) Inventor Yoichi Inmaki 6-35, Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation

Claims (5)

[Claims] 1. A magnetic head comprising a magnetic core having a sliding surface with a magnetic gap formed thereon, and recording and reproducing information signals on a magnetic recording medium sliding on said sliding surface by an azimuth recording method. A groove is formed in the sliding surface so as to be parallel to a sliding direction of the magnetic recording medium and to be in contact with one end of the magnetic gap. The azimuth angle is 15 degrees or more, and the angle of the surface constituting one track width regulating groove of the magnetic gap with respect to the sliding direction, and the angle of the surface constituting the other track width regulating groove with respect to the sliding direction. Characterized in that the difference between them is within 20 degrees. 2. An angle of a surface constituting one track width regulating groove of the magnetic gap with respect to the sliding direction is 50 degrees, and an angle of a surface constituting the other track width regulating groove with respect to the sliding direction is 50 degrees. The magnetic head according to claim 1, wherein the angle is 30 degrees to 50 degrees. 3. The magnetic head according to claim 1, wherein the groove is filled with a non-magnetic material. 4. The recording method of the information signal is an overwriting recording method, wherein the groove is disposed on a side where overwriting is performed, and the groove is parallel to the sliding direction on the sliding surface, and 4. The magnetic head according to claim 1, wherein the magnetic head is formed in a straight line. 5. The magnetic gap is formed by joining two magnetic core halves via a gap material to each other and integrating them by thermal diffusion bonding between noble metals. The magnetic head according to claim 1.