JP3025990B2 - Manufacturing method of magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION This invention relates to a manufacturing method of a magnetic heads used in the VTR or the like.

[0002]

2. Description of the Related Art In recent years, in the field of magnetic recording such as a VTR, a magnetic recording medium having high coercive force and high residual magnetic flux density has been used in order to achieve high density recording. . Accordingly, the magnetic head is required to have a high saturation magnetic flux density and a high magnetic permeability. In order to satisfy these requirements, a so-called laminate head has been proposed in which a gap is formed by abutting magnetic core halves in which a soft magnetic film having a high saturation magnetic flux density and a high magnetic permeability is sandwiched between non-magnetic substrates. This laminating head stacks a plurality of soft magnetic layers with a thickness of 3 to 4 μm to a set track width via an insulating film in order to reduce the effect of eddy current loss generated at a high frequency band. Generally, the soft magnetic film is formed.

FIG. 11 is a perspective view of a conventionally proposed laminated laminating head. The conventional laminated laminating head shown in FIG. 11 forms a soft magnetic film 3 by laminating a soft magnetic layer 2 on a non-magnetic substrate 1a via an insulating layer (not shown), and forms a glass material ( (Not shown) and bonded to the non-magnetic substrate 1b to form the magnetic core half 4
a and 4b. These magnetic core halves 4a, 4b
A glass filling groove 5 for bonding is formed on the magnetic core half 4b, and a winding groove 6 is formed on the magnetic core half 4b as shown in the figure, and the magnetic core halves 4a and 4b are brought into contact with each other. A chip head is formed by bonding and integrating with the fusion glass 7 so as to be combined. A magnetic gap 8 is formed between the butting surfaces of the soft magnetic films 3.

By the way, next-generation VTs such as digital VTRs
The track width of the R magnetic head is becoming narrower with high-density recording. When a magnetic path is formed only by the soft magnetic film 3 as in a conventional laminated laminating head, the track width is reduced and the track width is reduced. A problem is that the volume of the magnetic path is also reduced, causing a reduction in the head output.

Conventionally, the following magnetic head has been proposed in order to cope with the above-mentioned decrease in head output. FIG.
Indicates a plane of the magnetic head, that is, a contact surface with the magnetic tape, and portions similar to those in FIG. 11 are denoted by the same reference numerals. In this figure, the magnetic core halves 4a and 4b formed by sandwiching the soft magnetic film 3 between a pair of non-magnetic substrates 1a and 1b in the film pressure direction and joining them together are arranged so that the end faces of the soft magnetic film 3 face each other. And a magnetic gap 8 is formed between the butting surfaces of the soft magnetic films 3. The soft magnetic film 3 provided at the position of the magnetic gap 8 is cut out from one side in the film pressure direction. Notch groove 9a,
9b regulates the track width of the magnetic gap 8 (see JP-A-5-101321).

In FIG. 12, the thickness of the soft magnetic film 3 in the film thickness direction near the magnetic gap 8 is larger than that of the other portions, so that the head output is considered to be improved. There are such disadvantages. That is, the thickness of the soft magnetic film 3 is set to be larger than the track width, and the track width is regulated by the notches 9a and 9b.
When inserting a and 9b, not a little processing distortion occurs,
This may cause a reduction in head output.

FIG. 13 shows a plane view of the magnetic head, and the same parts as those in FIG. 11 are denoted by the same reference numerals. In this figure, both sides of the soft magnetic film 3 are sandwiched between magnetic substrates 10a and 10b, and grooves 11a and 11b are formed in the magnetic substrates 10a and 10b so that the thickness of the soft magnetic film 3 itself becomes the track width. (See JP-A-6-150238). This FIG.
As compared with the vicinity of the magnetic gap 8 in which the magnetic material is only the soft magnetic film 3, the thickness of the magnetic substrates 10a and 10b is added to the soft magnetic film 3 in other portions, so that the head output is improved. However, it has the following disadvantages. That is, since the magnetic substrates 10a and 10b are arranged up to the gap line at the track end, the dimensional accuracy at the time of polishing the gap opposing surface must be very high. Magnetic substrates 10a, 1
Since 0b protrudes, it is difficult to control the track width, and mass productivity cannot be expected.

FIG. 14 also shows the plane of the magnetic head, and the same parts as those in FIG. 13 are denoted by the same reference numerals. In this figure, both sides of the soft magnetic film 3 are sandwiched between magnetic substrates 10a and 10b, and the magnetic substrates 10a and 10b are connected to the magnetic gap 8 so that the thickness of the soft magnetic film 3 itself becomes the track width. It does not reach the vicinity (see JP-A-6-150238). In FIG. 14, the thickness of the magnetic substrates 10a and 10b is added to the soft magnetic film 3 in other portions compared to the vicinity of the magnetic gap 8 in which the magnetic substance is only the soft magnetic film 3, so that the head output Is improved, but has the following disadvantages. That is, since the boundary between the magnetic substrates 10a and 10b and the fusion glass 7 is parallel to the magnetic gap 8, this boundary becomes a pseudo gap, and a reproduced signal from a track adjacent to the track being reproduced by the magnetic gap 8 is used. Is mixed.

FIG. 15 shows the magnetic head viewed from a slope, and the same parts as those in FIGS. 11 to 14 are denoted by the same reference numerals. In this figure, the front side including the portion to be the magnetic gap 8 on both sides of the soft magnetic film 3 is formed by the nonmagnetic substrates 1a and 1b, and the rear side is formed by the magnetic substrate 10a.
a and 10b (Japanese Patent Laid-Open No. 5-2255)
No. 15). In FIG. 15, the thickness of the magnetic substrates 10a and 10b is added to the soft magnetic film 3 on the rear side as compared with the front side where the magnetic substance is only the soft magnetic film 3, so that the head output is improved. Has the following disadvantages.
That is, in the case of FIG.
a and 1b are single crystal ferrites, and
Reference numerals a and 10b denote polycrystalline ferrites, and these substrates are bonded to each other to form a substrate. This bonding technique is a sophisticated and laborious operation.

[0010]

In the above-mentioned conventional magnetic head, as described above, processing distortion occurs in the soft magnetic film during manufacturing, which causes a reduction in output or a gap facing surface in the manufacturing process. The dimensional accuracy at the time of polishing must be very high, and a slight variation in the polishing amount causes the magnetic substrate to protrude above the gap line, making it difficult to control the track width or generating a pseudo gap. As a result, there are problems such as that a reproduction signal from a track adjacent to the track being reproduced is mixed due to the magnetic gap, and that it takes time to join the non-magnetic substrate and the magnetic substrate which form the substrate.

In view of the above, the present invention does not cause processing distortion in the soft magnetic film during manufacturing, eliminates the need for increasing the dimensional accuracy when polishing the gap opposing surface in the manufacturing process, and generates a pseudo gap. it is also not and it is an object to provide a method of manufacturing a magnetic <br/> heads which is not time-consuming for bonding the non-magnetic portion and the magnetic portion forming the substrate.

[0012]

A method of manufacturing a magnetic head according to the present invention for solving the above-mentioned problems and achieving the above object.
Law,

[0013] Magnetic material and non-magnetic material are alternately overlapped
Bonding step and the block formed by this bonding
Cut in an oblique direction from the
The process of forming a cuber and the cut surface is polished and softened.
A step of forming a magnetic film, and a step of forming the soft magnetic film.
The process of laminating and bonding the lock bars and the bonding
Cut perpendicular to the cut surface to create a magnetic core half block.
Forming a pair of magnetic core half blocks.
One or both of them are filled with winding grooves and glass for bonding.
The step of forming the grooves, the surface on which these grooves are formed and
Polishing the surface corresponding to the surface, and these polished surfaces
The soft magnetic films are opposed to each other via a non-magnetic gap material on the surfaces.
The two magnetic core half-blocks project from each other so as to face each other.
Filling the fused glass into the glass filling groove
And the block formed by this process is the azimuth angle
Forming a head chip by cutting at an angle
And The non-magnetic material is converted to crystallized glass
And the magnetic material may be ferrite.
May be configured.

[0014]

In the magnetic head manufactured by the above method , since the soft magnetic film is not processed in the vicinity of the magnetic gap at the time of manufacturing, no processing distortion occurs, and the gap facing surface in the manufacturing process is not generated. Even if the polishing amount slightly varies, the magnetic width does not protrude above the gap line, so that the track width can be easily controlled. Further, since the boundary between the magnetic portion and the non-magnetic portion constituting the substrate is inclined with respect to the magnetic gap, a pseudo gap does not occur. Furthermore, since the non-magnetic portion and the magnetic portion forming the substrate can be joined only by heating to a high temperature, the joining between the non-magnetic portion and the magnetic portion is simple, and production can be facilitated. .

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a schematic perspective view of a head chip, and FIGS. 2 to 9 are schematic views showing a process of manufacturing the head chip. There are places that I have not done. In FIG. 1, the same reference numerals as in FIG. 11 used for describing the conventional example denote the same parts, and a detailed description thereof will be omitted. The head chip shown in FIG.
The structure is such that a part of the non-magnetic substrate in the conventional head described in 1 is replaced with a magnetic material. That is, the substrates 15a,
15b, the substrate 15a includes the non-magnetic portion 16 and the magnetic portion 17
The substrate 15b is made of a non-magnetic material. The vicinity of the magnetic gap 8 in the soft magnetic film 3 is sandwiched between the non-magnetic portion 16 of the substrate 15a and the non-magnetic substrate 15b. The boundary between the non-magnetic portion 16 and the magnetic portion 17 of the substrate 15a is inclined with respect to the magnetic gap 8.

Next, a method for manufacturing the magnetic head will be described. As shown in FIG. 2, ferrite 18 which is a magnetic material and crystallized glass 19 which is non-magnetic are alternately arranged, and heated at a high temperature while pressurizing in both directions indicated by arrows. By this heating, the vitreous of the crystallized glass 19 is melted and bonded. The block formed by this bonding is cut along the dashed line. FIG. 3 shows the block bar 20 in the cut state. The block bar 20 is cut along the chain line in FIG. The upper and lower surfaces of the block bar 21 in FIG. 3 are polished, and a soft magnetic thin layer is laminated on the upper surface of the block bar 21 with an insulating film interposed therebetween as shown in FIG. Then, a glass material 22 is coated on the upper surface by sputtering, vapor deposition, or the like.

The block bars 21 are overlapped as shown in FIG. 5 and are bonded by heating at a high temperature while pressing in the direction of the arrow. Next, the magnetic core half blocks A and B are formed by cutting as shown by the alternate long and short dash line in FIG. These magnetic core half blocks A and B are provided with an upper end glass groove 23 and a glass filling groove 24 for bonding as shown in FIG. 6, and the magnetic core half block B is also provided with a winding groove 25.

Then, a gap material is sputtered on the surface facing the gap, and butted so that the ends of the soft magnetic films 3 coincide with each other, and as shown in FIG.
The glass materials 26 and 27 are inserted into the plate 4 and heated at a high temperature while being pressed in the direction of the arrow, so that the magnetic core half blocks A and B are bonded to each other. Here, the gap material may be a glass material that can be bonded.

Thereafter, as shown in FIG. 8, the surface 28 serving as the tape sliding surface is cylindrically ground and cut along the alternate long and short dash line to obtain the head chip as shown in FIG. In FIG. 1, the bonding glass filling groove 5 is formed by the filling groove 24, the winding groove 6 is formed by the winding groove 25, the nonmagnetic portion 16 of the substrate 15a is formed by crystallized glass 19, and the magnetic portion 17 is formed by ferrite. 18, and the substrate 15b is made of the crystallized glass 1
9 respectively. FIG. 9 shows this head chip viewed from the tape sliding surface side, and the same parts as those in FIG. 1 are denoted by the same reference numerals. The temperature at which the glass material is heated and bonded in each step is as follows: the bonding temperature between the ferrite 18 and the crystallized glass 19 in FIG. 2> the bonding temperature in FIG.
The bonding temperature should be. Also, the glass material must be selected to melt at each temperature.

In the above embodiment, the substrate 15a is
6 and the magnetic portion 17, and the substrate 15b is made of a non-magnetic material. However, both substrates may be made of a magnetic portion and a non-magnetic portion. In the above-described manufacturing process,
Although the crystallized glass 19 is used as the non-magnetic material, ceramic can be used. In this case, it is necessary to coat a glass material on the surface of the ferrite or ceramic in advance by sputtering or vapor deposition. In the above embodiment, in order to facilitate understanding, the substrates 15a,
Although it has been described that the direction of the plate surface in the longitudinal direction of 15b and the magnetic gap 8 are orthogonal to each other, the direction between the plate surfaces of the substrates 15a and 15b and the magnetic gap 8 is actually as illustrated in FIG. Are shifted from the perpendicular direction so as to form an azimuth angle. Such an azimuth angle can be obtained by selecting the cutting direction described with reference to FIG. In FIG. 10, the same reference numerals as those in FIG. 9 denote the same parts.

The above-mentioned crystallized glass refers to a glass which, when heated, vitreous melts to obtain an adhesive ability and does not change its shape.

[0022]

As described above, according to the method of the present invention ,
In the manufactured magnetic head, even if the track width is narrower than the conventional laminating head, the output does not decrease, high output is obtained, and the soft magnetic film is not processed near the magnetic gap during manufacturing Therefore, there is no processing distortion, and even if there is a slight variation in the polishing amount of the gap opposing surface in the manufacturing process, the magnetic portion does not protrude above the gap line, so that track width control is easy. Become. Further, since the boundary between the magnetic portion and the non-magnetic portion constituting the substrate is inclined with respect to the magnetic gap, a pseudo gap does not occur. Furthermore, since the non-magnetic portion and the magnetic portion forming the substrate can be joined only by heating to a high temperature, the joining of the non-magnetic portion and the magnetic portion is simple, and the production can be facilitated.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a head chip manufactured by the method of the present invention.

FIG. 2 is a schematic view showing a manufacturing process of the present invention.

FIG. 3 is a schematic view showing a manufacturing process of the present invention.

FIG. 4 is a schematic view showing a manufacturing process of the present invention.

FIG. 5 is a schematic view showing a manufacturing process of the present invention.

FIG. 6 is a schematic view showing a manufacturing process of the present invention.

FIG. 7 is a schematic view showing a manufacturing process of the present invention.

FIG. 8 is a schematic view showing a manufacturing process of the present invention.

FIG. 9 is a schematic view showing a manufacturing process of the present invention.

FIG. 10 is a schematic plan view showing a specific example of one manufactured by the method of the present invention.

FIG. 11 is a perspective view showing a conventional example.

FIG. 12 is a plan view showing a conventional example.

FIG. 13 is a plan view showing a conventional example.

FIG. 14 is a plan view showing a conventional example.

FIG. 15 is a perspective view showing a conventional example.

[Explanation of symbols]

 Reference Signs List 2 Soft magnetic layer 3 Soft magnetic film 4a, 4b Magnetic core half 5, 24 Glass filling groove for bonding 6, 25 Winding groove 7 Fused glass 8 Magnetic gap 15a, 15b Substrate 16 Non-magnetic part 17 Magnetic part 18 Ferrite 19 Crystallized glass 20, 21 Block bar 22 Glass material 23 Upper glass groove 26, 27 Glass material A, B Magnetic core half block &#26;

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-94418 (JP, A) JP-A-6-111224 (JP, A) JP-A-3-250406 (JP, A) JP-A-3- 46308 (JP, A) JP-A-7-153016 (JP, A) JP-A-3-86905 (JP, A) JP-A-60-26609 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G11B 5/127-5/255

Claims (3)

(57) [Claims] A magnetic material and a non-magnetic material are alternately overlapped.
Bonding step and the block formed by this bonding
Is cut in the direction inclined from the
Polishing the cut bar and the process of forming the cut bar,
Forming a soft magnetic film and forming the soft magnetic film
The process of laminating and bonding block bars and bonding
Cut perpendicular to the cut surface to form the magnetic core half block.
Forming a pair of magnetic core half blocks;
One or both of them are filled with winding grooves and glass for bonding.
The step of forming the grooves, the surface on which these grooves are formed and
Polishing the surface corresponding to the surface, and these polished surfaces
The soft magnetic films are opposed to each other via a non-magnetic gap material on the surfaces.
The two magnetic core half-blocks project from each other so as to face each other.
Filling the fused glass into the glass filling groove
And the block formed by this process is the azimuth angle
Forming a head chip by cutting at an angle
A method for manufacturing a magnetic head comprising: 2. The nonmagnetic material is made of crystallized glass.
2. The method for manufacturing a magnetic head according to claim 1, wherein: 3. The magnetic body is made of ferrite.
The method of manufacturing a magnetic head according to claim 1, wherein
Law.