JP2959909B2 - Magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head having a novel structure capable of reducing the size of a magnetic circuit and improving high-frequency compatibility.

[0002]

2. Description of the Related Art As signals recorded magnetically on a magnetic tape have become higher in density, a magnetic tape such as a metal tape having an excellent magnetic layer having a high residual magnetic flux density has been used. In a magnetic head applied to a magnetic tape having a high coercive force such as a metal tape, it is necessary to increase the magnetic field intensity generated by the magnetic gap. Further, as the density of signals to be recorded increases, it is necessary to further narrow the track width of the magnetic head.

Conventionally, a magnetic head A having a structure shown in FIG. 12 is known as a conventional example of a magnetic head provided to satisfy such a demand. This magnetic head A
Are formed by welding and integrating the magnetic core halves 1 and 1 with a bonding material such as glass. Each of the magnetic core halves 1 has a metal magnetic film 2 formed of a plate-shaped side core half 3 made of a non-magnetic material. 3 and are integrated. The metal magnetic film 2 is formed by laminating a metal magnetic thin film of a high magnetic permeability alloy together with an interlayer insulating layer by a film forming method such as sputtering, and the thickness of the metal magnetic film 2 is set to a value equal to the track width. I have. In addition,
The medium facing surface 4 of the magnetic head A is polished into a curved surface in consideration of resistance when sliding on a magnetic tape.

In the medium facing surface 4, a magnetic gap 5 is formed in a portion where the metal magnetic films 2 and 2 are joined with a gap layer made of a non-magnetic material interposed therebetween, and a magnetic core half 1 is formed. 1 is joined to the side of one of the magnetic core halves 1, and a winding window 6 is formed.

On the other hand, as another conventional example of a magnetic head provided to satisfy the above demand, a magnetic head B having a structure shown in FIGS. 13 and 14 is known. The magnetic head B includes a pair of ferrite magnetic core halves 11, 11
Are formed on the sides of the metal core film 11 and the gap layer 13 so as to cover the protrusions 11a, and the magnetic core halves 11, 11 are abutted by the protrusions 11a via the gap layer 13. , A main gap G is formed between the gap layers 13, 13, and the magnetic core halves 11, 11 are
The structure is formed by joining the MIG (Meta)
1 In Gap) type magnetic head.

The MIG-type magnetic head B can generate a strong and steep magnetic field from the magnetic gap as compared with a ferrite head having a configuration in which the metal magnetic film 14 is not used. It is an excellent one that can cope with high density, and is widely used as a magnetic head for recording a video of a VTR or a magnetic head for a digital tape recorder.

Conventionally, to manufacture a magnetic head B having the above structure, first, a magnetic head B made of a magnetic material such as ferrite is used.
Prepare core blocks, apply groove processing to these core blocks to form a plurality of irregularities, and stack a metal magnetic film on the surface of these irregularities by a film forming method such as sputtering,
Then, a SiO 2 film is formed on the metal magnetic
_A gap layer including _two layers is formed.

Next, the core blocks on which the gap layers have been formed are butted together via the gap layers, and glass is poured so as to fill the recessed portions at the butted portions, and the core blocks are joined together. Then, the joined core blocks are cut into a plurality of magnetic cores, and each magnetic core is subjected to finish processing, thereby simultaneously manufacturing a plurality of magnetic heads from the pair of core blocks.

In the conventional magnetic head A shown in FIG. 12, in manufacturing, in addition to the step of joining the magnetic core halves 1, 1 with a joining material such as glass, the side core halves 3, 3
In addition, in order to integrate the metal magnetic films 2, a step of joining them with an adhesive or the like must be performed, and there is a problem that the manufacturing process becomes complicated. In general, in order to make a magnetic head compatible with high frequencies, it is necessary to reduce the size of the magnetic circuit. However, in the magnetic head A having the configuration shown in FIG. There is a problem that the magnetic circuit cannot be further reduced in size because the magnetic circuit is formed on the entire surface.

On the other hand, in the conventional magnetic head B shown in FIGS. 13 and 14, since the magnetic core half 11 made of ferrite is used, the magnetic characteristics of the ferrite material itself are limited. Since the magnetic characteristics of the magnetic head 14 are suppressed, there is a limit in supporting high frequencies, and since the ferrite material occupies most of the magnetic core, there is a problem that the coil inductance of the magnetic head cannot be reduced.

Further, in the magnetic head B having the configuration shown in FIGS. 13 and 14, the parallel portion between the main gap G and the metal magnetic film 14 and the parallel portion between the main gap G and the gap layer 13 are long. In addition, since they are arranged on both sides of the main gap G, there is a problem that they form a pseudo gap and cause a swell in the frequency dependence characteristic of the reproduced output, that is, a so-called contour effect occurs.

In order to solve the above-mentioned problems, the present inventors filed an application on February 26, 1992 for a magnetic head having the following configuration. Hereinafter, the configuration of the magnetic head will be described with reference to the drawings. 9 to 11 show the structure of a first configuration example of this magnetic head. The magnetic head C of this first configuration example has a pair of left and right magnetic core halves 120, 120 on their side surfaces. The upper surfaces of the magnetic core halves 120, 120 in FIG. 9 serve as the medium facing surface 122. The magnetic core half 120 has a substantially rectangular plate-like half core 123 made of a nonmagnetic material such as crystallized glass or ceramics.
And a metal magnetic film 124 formed on the side of the half core 123.

A groove 125 is formed in a side surface to which the half cores 123 are joined, respectively.
25 is a bottom surface 125 a parallel to the side surface of the half core 123.
And an inner side surface 125 inclined with respect to the bottom surface 125a.
b, 125b, and one of the two inner side surfaces 125b reaches the medium facing surface 122 in an inclined state. Further, on the side surface of the half core 123, the groove 12
5 except for the other half core 123
Convex portion 123 whose surface is curved in an arc shape so as to bulge to the side
a is formed.

The entire side of the half core 123, that is,
The side surface of the half core 123 and the bottom surface 125a of the groove 125
In addition, a metal magnetic film 124 made of a soft magnetic alloy thin film or the like having a high magnetic permeability and a high saturation magnetic flux density is formed on each of the inner side surfaces 125b of the groove 125. This metal magnetic film 1
24 denotes a plurality of metal magnetic thin films 130 as shown in FIG.
Are individually laminated with an interlayer insulating layer 131 interposed therebetween.

The soft magnetic material forming the metal magnetic thin film 130 is made of Fe-Al- having a saturation magnetic flux density of 10,000 G or more.
A soft magnetic material having a higher saturation magnetic flux density than commonly known ferrite, such as a soft magnetic alloy such as a Si-based alloy sendust, a Fe-Al-Ta-C-based soft magnetic alloy, or an amorphous alloy, may be used as appropriate.

Further, as shown in FIG. 10, a metal magnetic film 124 of the pair of magnetic core halves 123 has an S
A gap layer composed of a nonmagnetic layer such as iO ₂ , Al ₂ O ₃ , CrSiO ₂ is formed to form a magnetic gap G. Then, the surface portion of each metal magnetic film 124 exposed on the medium facing surface 122 is curved in an arc shape so as to bulge toward the magnetic gap G side, and each metal magnetic film 124
The tip of the curved portion formed by 124 is closest to the magnetic gap G. Further, the tip portion of the metal magnetic film 124 curved toward the magnetic gap is closest to the magnetic gap G at the center of the magnetic gap G. Further, a hexagonal winding window 126 is formed at the joint on the side of the half cores 123, 123 by abutting the grooves 125, 125.
6 is filled with glass on the magnetic gap side,
1 is formed.

On the other hand, as shown in FIG.
At both ends in the thickness direction of the joining portion of the joining portions 23 and 123, a joining groove 123b formed by being sandwiched between the convex portions 123a of the half cores 123 and 123 is formed, and the joining groove 123b is filled with glass. A portion 128 is formed. Note that, on both sides of the magnetic head C shown in FIG.
9 is formed, and a winding coil is provided through one winding groove 129 and one end of the winding window 126.
A winding coil is provided through the other winding groove 129 and the other end of the winding window 126.

The magnetic head C having the above structure is a magnetic head.
Like A and B , it is used to perform magnetic recording and reproduction on a magnetic recording medium such as a magnetic tape. To do so, a current is applied to the winding coil provided on the magnetic head C to form a magnetic flux gradient outside the magnetic gap G, thereby magnetizing a desired portion of the magnetic recording medium. In this case, the metal magnetic thin film 130 having a high magnetic permeability and a high saturation magnetic flux density generates a steep magnetic field outside the magnetic gap G, so that even a magnetic recording medium having a magnetic layer with a high coercive force has room. it is possible to perform magnetic recording with, it is possible to correspond to the density of magnetic recording.

Since the metal magnetic films 124 formed along the groove 125 form an annular magnetic circuit that surrounds the periphery of the winding window 126, the magnetic structure shown in FIG. head a or, it is possible to reduce the size of the magnetic circuit compared to the magnetic head B of the structure <br/> MIG type shown in FIGS. 13 and 14. Thus the magnetic head A, there is an advantageous feature in the high frequency response than B, easily read magnetic information recorded on the magnetic recording medium by the miniaturization of the magnetic circuit, it is possible to also improve the efficiency at the time of reproduction.

In the magnetic head C having the above structure, the metal magnetic film 12 exposed on the medium facing surface 122 is formed.
4 and 124 are curved individually, approach the magnetic gap G, and gradually separate from the magnetic gap G.
Unlike the magnetic head B shown in FIGS. 13 and 14, in the metal magnetic films 124 and 124 having this configuration, there is no metal magnetic film portion arranged in parallel with the magnetic gap.
There is no generation of a pseudo gap, and no occurrence of waveform distortion due to the contour effect.

[0021]

However, in the magnetic head C having the above structure, as shown in FIG. 11, a metal magnetic film is exposed on the medium facing surface, and is sandwiched between these metal magnetic films. When such a magnetic head is used for a long period of time, the magnetic tape slides on the medium facing surface of the metal magnetic thin film in the metal magnetic film directly sandwiching the magnetic gap due to the magnetic gap being formed. And the metal magnetic thin film forming the magnetic gap is abraded and deformed, and in some cases, the interlayer insulating film constituting the underlayer of the metal magnetic thin film is exposed, There is a possibility that the magnetic gap is integrated and the width of the magnetic gap changes.

Accordingly, the present invention has been made in view of the above circumstances, and has as its object to provide a magnetic head which prevents deformation of a magnetic gap width, reduces the size of a magnetic circuit, and facilitates high frequency operation.

[0023]

In order to solve the above-mentioned problems, a magnetic head according to the present invention comprises a pair of half-cores made of a non-magnetic material and a metal magnetic film and an interlayer insulating layer formed on their side portions. The metal magnetic films are abutted with a gap layer interposed therebetween to form a magnetic gap between the metal magnetic films and are integrated, and one surface of a half core adjacent to a side surface of the half core is formed as a medium facing surface. In the magnetic head, a winding window is formed at a joining portion of the half core, an annular metal magnetic film surrounding the winding window is formed around the winding window, and the pair of metal magnetic films includes a plurality of metal magnetic films .
It is made of metal magnetic film and the gap surface from the winding window side
To the gap layer and approach each other
This metal magnet is provided to reach the medium facing surface.
At least one pair of metal magnetic films in the conductive film is a medium facing surface.
To form the magnetic gap, and
Wherein the metal magnetic film is formed to a thickness that extends from the surface of the gap to the deepest portion.

[0024]

The half core is made of a non-magnetic material, and an annular metal magnetic film is formed around the winding window.
The magnetic film from the winding window side to the gap surface.
To the medium facing surface while approaching each other at an angle to the
And the innermost metal magnetic film is formed to have a thickness from the gap surface portion to the deepest portion. Even if it is slightly worn, the metal magnetic film forming the magnetic gap is worn as in the magnetic head of the conventional structure, so that the interlayer insulating layer is not exposed, resulting in a change in the magnetic gap width. Such a problem is avoided. Therefore, by keeping the magnetic gap width at a constant value, deterioration of magnetic recording characteristics and occurrence of spacing loss can be avoided.

Further, since an annular magnetic circuit is formed by the metal magnetic film so as to surround the winding window formed at the junction of the non-magnetic half core, the magnetic circuit is smaller than the conventional structure. In addition, since recording and reproduction can be performed by the miniaturized magnetic circuit, recording and reproduction characteristics corresponding to high frequencies can be obtained. Further, since recording / reproduction can be performed only by the metal magnetic film, it is more advantageous than the conventional MIG type magnetic head in which the presence of the ferrite portion limits the high frequency response.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A magnetic head according to the present invention will be described below with reference to the drawings. FIGS. 1 to 3 show an embodiment of a magnetic head according to the present invention. A magnetic head D of this embodiment has a pair of left and right magnetic core halves 20, 20 with glass portions 21 on their side portions. The upper surface side of the magnetic core halves 20, 20 in FIG. 1 is a medium facing surface 22. The magnetic core half 20 is mainly composed of a substantially rectangular plate-shaped half core 23 made of a nonmagnetic material such as crystallized glass or ceramics, and a metal magnetic film 24 formed on the side of the half core 23. ing.

A groove 25 is formed in the side surface to which the half cores 23 are joined, respectively.
Consists of a bottom surface 25a parallel to the side surface of the half core 23 and inner surfaces 25b, 25b inclined with respect to the bottom surface 25a. One of the two inner surfaces 25b reaches the medium facing surface 22 in an inclined state. Have been. On the side surface of the half core 23, except for the groove 25, a convex portion 23a whose surface is curved in an arc shape is formed so as to bulge toward the other half core 23 facing the other half core.

A soft magnetic alloy thin film having a high magnetic permeability and a high saturation magnetic flux density is provided on the entire side portion of the half core 23, that is, on the side surface of the half core 23, the bottom surface 25a of the groove portion 25, and the inner side surface 25b of the groove portion 25. Metal magnetic film 24 made of, for example,
Are formed. And each half core 23, 23
Hexagonal winding window with butted grooves 25, 25
26 are formed, whereby each metal magnetic film 24, 24
Are arranged annularly around the winding window 26. FIG. 2 and
As shown in FIG.
The tall magnetic films 24, 24 are made of SiO ₂ , Al ₂ O ₃ , CrS
A gap layer 27 made of a nonmagnetic layer such as iO ₂ is sandwiched therebetween.
But the magnetic gap G is formed
You. The gap layer 27 is formed on the medium sliding surface 22 (the gap surface).
Portion G1) and from the gap surface portion G1.
It extends to the deepest part G2. Metal magnetic films 24, 24
Is, as shown in FIG. 3, a plurality of metal magnetic films 30 , 30 ,
30a is formed by laminating an interlayer insulating layer 31 to individually and the innermost metallic magnetic films 30a, 30a are, formic
Gap surface of magnetic gap G in contact with gap layer 27
From G1 to the deepest part G2 . Furthermore, this metal magnetism
The membranes 24, 24 are arranged on the gap surface G1 from the winding window 26 side.
Toward the gap layer 27 and approach each other.
It is provided so as to reach the medium facing surface 22.
Then, the innermost periphery of the metal magnetic films 24, 24
Metal magnetic films 30a, 30a are exposed on the medium facing surface 22.
Thus, a magnetic gap G is formed. Then, the thickness t of the innermost metal magnetic layer 30a is the angle between the gap depth direction and the innermost metallic magnetic film 30a theta
And the following relationship is satisfied between θ and the magnetic gap depth Gd. t> Gdsinθ

Further, in the magnetic head D of the structure, the order of 3~30μm the gap depth Gd, 0.1 to 0.4 [mu] m about the thickness of the interlayer insulating layer 31, the metal magnetic film 3
0 is about 3 to 5 μm except for the innermost periphery of the gap layer 2.
7 can be about 0.2 to 0.5 μm.

The soft magnetic material forming the metal magnetic film 30 is made of Fe-Al-S having a saturation magnetic flux density of 10,000 G or more, as in the conventional example shown in FIGS.
A soft magnetic material having a higher saturation magnetic flux density than commonly known ferrite, such as an i-based alloy, a soft magnetic alloy such as an Fe-Ta-C system, and an amorphous alloy, may be used as appropriate.

The material for forming the metal magnetic film 30 is preferably an Fe-Ta-C-based material, an Fe-MO-based material (M represents at least one of Zr and Hf), and a Fe-Ta-C-based material. Co-MO system, Fe-Co-MOX
A soft magnetic thin film or the like can be used. Of these soft magnetic thin films, preferably, the applicant of the present invention firstly discloses Japanese Patent Application Nos. 2-26851 and 3-31503.
A patent application is used in the specification of No. 6, etc. Preferably, the composition range of these soft magnetic thin films is
Fe _50-96 -M _2-30 -C _0.5-25 (M = Ti, Zr, H
f, Nb, Ta, Mo, W) Fe _70-96 M _1-12 O _3-25 ,
Fe _13-86 Co _10-50 M _1-12 O _3-25 , Fe _13-85 Co _10-50
M _1-12 O _3-25 X _{0.1-26 and the} like, but it goes without saying that materials other than these compositions may be used. (In the above composition formula, Fe _70-96 means that the content of Fe is atomic%.
Indicates that 70% ≦ Fe ≦ 96%. )

Further, as shown in FIG. 2, the medium facing surface 22
The surface portion of each metal magnetic film 24 exposed to the magnetic field is curved in an arc shape so as to bulge toward the magnetic gap G side, and the magnetic gap is formed at the tip of the curved portion formed by each metal magnetic film 24. Closest to G. The tip of the metal magnetic film 24 curved toward the magnetic gap is closest to the magnetic gap G. The distal end portion curved toward the magnetic gap is closest to the magnetic gap G at the center of the magnetic gap G. The innermost layer of the metal magnetic film 24 is formed with the magnetic gap G in order to form the magnetic gap G.
Are provided in a state parallel to. Furthermore, the winding window 26
Is filled with glass on the magnetic gap G side of
Are formed.

On the other hand, as shown in FIG.
At both ends in the thickness direction of the joints 3 and 23, a joining groove 23b formed by being sandwiched between the convex portions 23a of the half cores 23 and 23 is formed, and the joining groove 23b is filled with glass. A part 28 is formed. A winding groove 29 is formed at a height position corresponding to the winding window 26 on both sides of the magnetic head D shown in FIG. , And a winding coil is provided through the other winding groove 29 and the other end of the winding window 26.

The magnetic head D having the above-described structure is used for performing magnetic recording and reproduction on a magnetic recording medium such as a magnetic tape, like the conventional magnetic head. In order to do so, the winding coil provided on the magnetic head D may be energized to form a magnetic flux gradient outside the magnetic gap G, thereby magnetizing a desired portion of the magnetic recording medium. in this case,
Since the metal magnetic film 30 having a high magnetic permeability and a high saturation magnetic flux density generates a steep magnetic field outside the magnetic gap G, even a magnetic recording medium having a magnetic layer with a high coercive force can perform magnetic recording with a margin. It is possible to cope with high density of magnetic recording. Further, as compared with a conventional MIG type magnetic head using a ferrite portion and a metal magnetic thin film, there is no ferrite portion, which is advantageous for high-frequency magnetic recording.

Further, the half core is made of a non-magnetic material, and a plurality of metal magnetic films 24 are formed around the winding window 26 .
24 , the innermost metal magnetic film 30a of the metal magnetic films 24, 24 is exposed to the medium facing surface to form a magnetic gap, and the metal magnetic film 30a extends from the gap surface portion G1 to the deepest portion. Even if the periphery of the magnetic gap G wears a little due to the sliding of the magnetic tape, the metal magnetic film forming the magnetic gap G like the magnetic head of the conventional structure can be formed by forming the thickness to reach G2. It is possible to avoid a problem that the interlayer insulating layer is exposed due to abrasion and abrasion deformation, resulting in a change in the magnetic gap width. Therefore, by maintaining the magnetic gap width at a constant value as in the magnetic head according to the present invention, it is possible to avoid deterioration of magnetic recording characteristics and occurrence of spacing loss.

Since the metal magnetic films 24, 24 formed along the groove 25 form an annular magnetic circuit surrounding the periphery of the winding window 26, the magnetic head A of the conventional structure shown in FIG. Alternatively, the size of the magnetic circuit can be reduced as compared with the conventional MIG type magnetic head B shown in FIGS. Therefore, the magnetic head has a feature that is more advantageous in supporting high frequencies than the conventional magnetic head, and the magnetic information recorded on the magnetic recording medium can be easily read by reducing the size of the magnetic circuit, and the efficiency at the time of reproduction can be improved. Further, since the metal magnetic films 24 provided around the winding window 26 are close to each other while being inclined toward the magnetic gap G, the metal magnetic films 24 have a shape advantageous for generating a magnetic field in the magnetic gap G. .

In the magnetic head D having the above-described structure, the surface portions of the metal magnetic films 24, 24 exposed on the medium facing surface 22 are individually curved and approach the magnetic gap G, and approach at one point. Since the other portions are gradually separated from the magnetic gap G, unlike the conventional magnetic head B shown in FIGS. 13 and 14, the metal magnetic films 24 and 24 having this configuration are arranged in parallel with the magnetic gap G. Since there is no metal magnetic film portion to be formed, there is no pseudo gap,
There is no occurrence of waveform distortion due to the contour effect.

Next, the magnetic head C having the structure shown in FIGS.
An example of a method for manufacturing the will be described. Magnetic head D
First, a flat rectangular plate-shaped block 38 made of a non-magnetic material such as crystallized glass or ceramic is used, and the upper surface of the block 38 is subjected to a grinding process using a grindstone or the like. A plurality of V-shaped grooves 39 as shown in FIG. Thereby, between the V-shaped grooves 39, elongated protrusions 40 each having a triangular side surface are formed. Subsequently, the tip of each projection 40 is processed into a curved surface as shown in FIG. 5 by a technique such as laser beam processing, reverse sputtering, dry etching, and pad polishing.

Next, a groove is formed in the block 38 using a grindstone or the like, and a groove 41 as shown in FIG.
9 is formed in a direction perpendicular to the direction. The groove 41 has a bottom surface 41 a formed parallel to the top surface of the block 40,
On both sides of the bottom surface 41a, an inner side surface 41b is formed obliquely with respect to the bottom surface 41a.

Subsequently, as shown in FIG. 7, a plurality of metal magnetic films and an interlayer insulating layer are alternately laminated on the entire upper surface of the block 40 by a film forming means such as sputtering or vacuum evaporation to form a metal magnetic film 45. I do. At this time, the thickness t of the uppermost metal magnetic film is determined by the angle θ between the gap depth direction and the innermost metal magnetic film 30a and the magnetic gap depth G.
It is formed so as to satisfy the relationship of t> Gdsinθ between d.

A gap layer is coated on the innermost metal magnetic film. Note that the upper surface of the protrusion 40 and the V-shaped groove 3
The laminated film formed on the portion excluding the upper surface of 9 is polished and removed until it reaches the same height as the laminated film formed on the tip of the projection 40.

After forming a pair of blocks 40 in the state shown in FIG. 7, the metal magnetic films 45, 45 are formed as shown in FIG.
In addition, the grooves 41, 41 are aligned with each other to butt the blocks 40, 40, and the molten glass is caused to flow into the cavity formed in the butt portion, so that the blocks 40, 40 are aligned.
40 are joined. In this joining operation, a glass rod for joining is housed in the hollow portion, which is melted and
It is performed by pouring into each part of 0.

Next, the blocks 40, 40 joined in the state shown in FIG. 8 are cut out along the chain line in FIG. 8, and the medium facing surfaces of the blocks 40, 40 are polished to form the structure shown in FIG. Can be simultaneously manufactured from the blocks 40 and 40 in large numbers.

By performing the above-described method, the magnetic head D
, A large number of magnetic heads D can be manufactured simultaneously from the blocks 40 and 40. According to the above method, the MI described above with reference to FIGS.
As in the case of the G-type magnetic head B, a large number of magnetic heads C can be manufactured by performing a block cutting process, a metal magnetic film forming process, a glass welding process, and a cutting process. Thus, the magnetic head D can be manufactured in a similar procedure. Therefore, a high-performance magnetic head D having a novel structure can be manufactured by the conventional manufacturing equipment for the magnetic head B. In the above method, the step of welding with glass is only required once, so that the number of welding steps is smaller than that of the magnetic head A having the structure shown in FIG. It can be manufactured with.

In the obtained magnetic head D, the convex portion 23a of the half core 23 projects in an arc shape toward the magnetic gap G. The shape of the projecting portion is a triangular mountain shape formed in the block 38. It can be set freely according to the curvature at the time of bending the tip of the projection 40. Therefore, the protrusion 40 for forming the special shape of the metal thin film 24 on the block 40 for suppressing the contour effect.
Can be easily determined by processing the tip portion of.

In the above-described embodiment, the metal magnetic film 24 is formed to be curved in an arc shape. However, the metal magnetic film 24 may be formed to be curved in an arc on the medium facing surface 22. Half cores 23, 2
3 has a magnetic gap G
The contour effect can be suppressed if the metal magnetic film 24 is closest to each other at the center portion of the metal film 24 and is gradually separated from the magnetic gap G at the other portions, so that the curved state of the metal magnetic film 24 can take various shapes. Therefore, the term “the metal magnetic film 24 is curved” in the present invention includes a state in which a plurality of planar metal magnetic films are connected while being inclined at a small angle and are curved as a whole.

Further, the half core 23 is made of a non-magnetic material, and a plurality of metal magnetic films 2 are formed around the winding window 26.
4 and 24 are formed in an annular shape, and the innermost metal magnetic film 30a of the metal magnetic film 24 is exposed to the medium facing surface 22 to form a magnetic gap G.
By but made is formed to a thickness reaching to the deepest G2 from the gap surface portion G1, the even magnetic gap G around worn by sliding of the magnetic tape, the magnetic gap G as the magnetic head of the conventional structure It is possible to avoid a problem that the interlayer insulating layer is exposed due to wear and deformation of the metal magnetic film that forms the magnetic layer, resulting in a change in the magnetic gap width. Therefore, by maintaining the magnetic gap width at a constant value as in the magnetic head according to the present invention, it is possible to avoid deterioration of magnetic recording characteristics and occurrence of spacing loss.

[0048]

As described above, according to the present invention, the half core is made of a non-magnetic material, and a plurality of metal magnetic films are formed in a ring around the winding window. The two metal magnetic films are exposed on the medium facing surface to form a magnetic gap, and the metal magnetic film is formed to a thickness that extends from the surface of the gap to the deepest portion, so that the magnetic tape slides around the magnetic gap. Even if it is worn by the magnetic head, the magnetic
By the metal magnetic film forming the-up to wear and abrasion deformation, it will be exposed interlayer insulating layer, resulting in it is possible to avoid the problem such as a magnetic gap width is changed. Therefore, the magnetic head of the present invention can keep the magnetic gap width at a constant value, and can avoid deterioration of magnetic recording characteristics and occurrence of spacing loss. The metal magnetic film provided around the winding window is magnetic.
Because they are close to each other while leaning toward the gap,
A magnetic field can be generated efficiently in the magnetic gap.
You.

Further, since magnetic recording and reproduction can be performed only by a magnetic circuit using a metal magnetic film, the present invention is more advantageous than a conventional MIG type magnetic head in which the presence of a ferrite portion has a limit in supporting high frequencies.

[Brief description of the drawings]

FIG. 1 is a sectional view of a magnetic head according to an embodiment of the present invention.

FIG. 2 is a plan view of the magnetic head shown in FIG.

FIG. 3 is an enlarged view of a main part of the magnetic head shown in FIG. 1;

FIG. 4 is a perspective view showing a state in which a V-shaped groove is formed in a non-magnetic block used for carrying out the method of the present invention.

FIG. 5 is a side view showing a state in which a tip portion of the V-shaped groove shown in FIG. 4 is processed.

FIG. 6 is a perspective view showing a state in which a groove is formed in the block shown in FIG. 5;

FIG. 7 is a front view showing a state where a metal magnetic film is laminated on the same block.

FIG. 8 is a plan view showing a state where the blocks shown in FIG. 7 are butted.

FIG. 9 is a perspective view showing one configuration example of a conventional magnetic head.

FIG. 10 is a plan view of the magnetic head shown in FIG. 9;

FIG. 11 is an enlarged view of a main part of the magnetic head shown in FIG. 9;

FIG. 12 is a perspective view showing an example of a structure of a conventional magnetic head.

FIG. 13 is a perspective view showing a structural example of a conventional MIG type magnetic head.

FIG. 14 is a plan view of the magnetic head shown in FIG. 13;

[Explanation of symbols]

D Magnetic head G Gap G1 Gap surface portion G2 Deepest portion 20 Magnetic core half 21 Glass portion 28 Glass portion 22 Medium facing surface 23 Half core 23a Projection 24 Metal magnetic film 25 Groove 25a Bottom surface 25b Inner side surface 26 Winding window 27 Gap layer Reference Signs List 30 metal magnetic film 30a innermost metal magnetic film 31 interlayer insulating film 38 block 39 V-shaped groove 40 convex part 41 groove part 45 metal magnetic film

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-170014 (JP, A) JP-A-2-162505 (JP, A) JP-A-1-92908 (JP, A) (58) Investigation Field (Int.Cl. ⁶ , DB name) G11B 5/127-5/255

Claims (1)

(57) [Claims] 1. A pair of half cores made of a non-magnetic material,
A metal magnetic film formed on those side portions and a metal magnetic film including an interlayer insulating layer are abutted through a gap layer,
In a magnetic head in which a magnetic gap is formed between the metal magnetic films so as to be integrated and one surface of a half core adjacent to a side surface of the half core is formed as a medium facing surface, a winding is formed around a joint portion of the half core. windows are formed, an annular metal magnetic film surrounding it around the winding window is formed, prior to
Details 1. pair of metal magnetic film, and ing from a plurality of metal magnetic film
In both cases, the gap layer extends from the winding window side to the gap surface.
Approaching the medium facing surface while approaching each other
It provided so that said magnetic at least one pair of magnetic metal film is exposed in the medium facing surface in the metal magnetic film
A magnetic head, wherein a gap is formed, and an innermost metal magnetic film is formed so as to have a thickness from a surface portion of the gap to a deepest portion.