JPH08339522A - Production of magnetic head - Google Patents

Abstract

PURPOSE: To maintain the load acting on a slicer constant and to improve cutting rectilinearity by executing cutting of a work with the specified slicer dividedly plural times. CONSTITUTION: The unnecessary parts 95 at both ends and plural gap bars are cut from a gapped plate 93 formed of these unnecessary parts 95 and the plural gap bars by rotating the slicer having a disk-shaped blade consisting of diamond abrasive grains. The load acting on the slicer is made nearly constant and the cutting rectilinearity is enhanced in spite of increasing of the cutting speed two times, etc., if the cutting with the slicer is divided in three times, etc., and the depths of cuts H1 to H3 of the slicers of the respective times are respectively specified to within 1mm, for instance, 0.9mm, at the time of cutting. Thereby, the working accuracy is improved and the production yield is drastically enhanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to a method of manufacturing a magnetic head, and more particularly Fe-Si-A.
a magnetic head constructed by abutting and joining two core halves having a structure in which a magnetic thin film such as an l-alloy magnetic film is sandwiched between non-magnetic substrates with a predetermined gap length, or
The present invention relates to a method of manufacturing a flying magnetic head having a thin film laminated head core formed by laminating magnetic thin films such as Fe-Si-Al alloy magnetic films on a substrate.

[0002]

2. Description of the Related Art The recent improvement in recording density in the field of magnetic recording technology is accompanied by a consequent narrowing of tracks for a magnetic head as an electromagnetic transducer, an increase in saturation magnetization of a core material, and a transparency in a high frequency region. There is an increasing demand for improved magnetic susceptibility.

In recent years, as a magnetic head satisfying the above requirements in the field of magnetic recording, for example, a magnetic thin film M such as a Fe--Si--Al alloy magnetic film shown in FIG.
A thin film laminated magnetic head 1 constructed by abutting and joining two core halves 1A and 1B having a structure sandwiched between non-magnetic substrates 2 and 2 with a predetermined gap length has attracted attention. An example of a method of manufacturing such a magnetic head 1 is shown in FIG.
A brief explanation will be given with reference to.

In FIG. 6, first, a magnetic thin film laminated body, that is, a laminated block 90, which is formed by laminating a plurality of non-magnetic substrates on which a magnetic film is formed by a sputtering method or the like with a glass film interposed therebetween (see FIG. 6 (A)), the laminated block 90 is cut in a direction orthogonal to the laminating direction to form an I core plate 91 and a C core plate 92 (FIG. 6).
(B)).

Next, as indicated by reference numeral 82, the surface of the C core plate 92 is subjected to grooving for an apex glass mold, grooving for a winding groove, etc., and then the C core plate 92. After the track is aligned with the 92 and the I core plate 91 via the gap spacer (g), heat and pressure bonding, so-called gap welding is performed to obtain a gapped plate 93 (FIG. 6C).

Further, the gapped plate 93 is processed by grinding or the like to a predetermined thickness, and the apex glass 80 is molded on the apex portion (FIG. 6 (D)).
I core 1A and C as shown in FIG.
The magnetic head 1 including the core 1B was obtained.

[0007]

By the way, from the gapped plate 93 to the magnetic head 1 during the above manufacturing process.
7A, the gapped plate 93 is first cut in a direction orthogonal to the magnetic film M, as shown in FIG.
It is necessary to obtain (B)). Then this bar 9
I core 1A as shown in FIG.
Thus, the magnetic head 1 including the C core 1B is obtained.

Conventionally, the step of cutting the gapped plate 93 into a bar shape has been performed using a slicer.
That is, the gapped plate 93 was cut by one cutting process by setting the cutting amount of the slicer to be larger than the thickness (H) of the gapped plate 93. The slicer 10 to be used includes a disk-shaped blade 12 made of diamond abrasive grains, as shown in FIG.
The blade 12 is rotated to cut the workpiece. The blade 12 is sandwiched from both sides by a disk-shaped spacer 14 made of SUS except for the outer peripheral portion necessary for processing.

The above magnetic head is a fine one,
The quality of processing has a great influence on the manufacturing yield. That is, as shown by the alternate long and short dash line in FIG. 7B, when the bar 94 is cut from the gapped plate 93 and the cut surface has a curved shape, the dimension of the gap depth (GD) of the finished magnetic head. Sometimes deviates from the standard value, and there is a problem that the yield decreases.

Therefore, as a result of many researches and experiments, the present inventor has found that the cutting is curved because of problems in the workability of the workpiece and the slicer 10. In particular, the width (T) of the blade 12 is It was considered that the blade 12 was deformed due to the load applied to the blade 12 during the machining because the thickness was as thin as 0.2 mm, and the straightness of the cutting was deteriorated.

FIG. 9 shows a slicer 1 for a ceramic substrate.
It is a figure which shows the relationship between the amount of cuts when it cut | disconnects at 0, and the load applied to a slicer. From this figure, the depth of cut is 1.
If it is 0 mm or less, especially 0.9 mm or less, slicer 1
It can be seen that the load applied to 0 is extremely reduced, and the load applied to the slicer 10 is constant in a range smaller than 0.9 mm. Furthermore, when the depth of cut is 0.9 mm or less, the load applied to the slicer 10 was slightly increased even if the cutting speed was doubled. Therefore, the inventor of the present invention has a cutting depth of 1.0 mm, preferably 0.9
It was found that when the cutting speed was doubled and the cutting was performed plural times within a range not exceeding mm, the straightness of cutting was remarkably improved. The present invention is based on such a new finding.

An object of the present invention is to provide a method of manufacturing a magnetic head in which the straightness of cutting is improved, the processing accuracy is increased, and the manufacturing yield is remarkably improved.

[0013]

The above object can be achieved by the method of manufacturing a magnetic head according to the present invention. In summary, the present invention, in the manufacturing method of the magnetic head, in the manufacturing method of the magnetic head, including the step of cutting the workpiece by a slicer equipped with a disk-shaped blade made of diamond abrasive grains,
The method of manufacturing a magnetic head is characterized in that the step of cutting the workpiece with the slicer is performed in plural times. When the work piece is a non-magnetic ceramic substrate, the cutting amount per cut in the cutting step is 1.0 mm.
The following is preferably 0.9 mm or less. It is preferably applied when the non-magnetic ceramic substrate is difficult to work like a CoO—NiO—Al ₂ O ₃ substrate.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A method of manufacturing a magnetic head according to the present invention will be described in more detail below with reference to the drawings. The principle of the present invention can be applied to a method of manufacturing a magnetic head including a step of cutting an object to be processed by a slicer having a disk-shaped blade made of diamond abrasive grains during the manufacturing process of the magnetic head. next,
The present invention will be described with reference to examples.

Example 1 In this example, the magnetic head manufactured has a magnetic thin film M such as an Fe—Si—Al alloy magnetic film shown in FIG. 5 sandwiched between non-magnetic substrates 2 and 2. A thin film laminated magnetic head 1 constituted by abutting and joining two core halves 1A and 1B having a structure with a predetermined gap length, and the magnetic head 1 is described with reference to FIGS. 6 and 7. It shall be manufactured by the same manufacturing method. In this embodiment, the non-magnetic substrate 2 is mainly composed of CoO and NiO, and Al
Ceramic substrate prepared by adding ₂ O _3, that is,
Using CoO-NiO-Al ₂ O ₃ substrate.

That is, according to the method of manufacturing the magnetic head of the present embodiment, in FIG. 6, first, a plurality of non-magnetic substrates having magnetic films formed by a sputtering method or the like are laminated by interposing glass films therebetween. The laminated magnetic thin film, that is, the laminated block 90 is manufactured (FIG. 6A), and the laminated block 90 is cut in the direction orthogonal to the laminating direction to form the I core plate 91 and the C core plate 92 ( Figure 6
(B)).

Next, as shown by reference numeral 82, the surface of the C core plate 92 is subjected to grooving for an apex glass mold and grooving for a winding groove, and then the C core plate 92. 92 and I core plate 91
After the tracks are aligned with each other via the gap spacer (g), heat and pressure bonding, that is, so-called gap welding is performed to obtain a gapped plate 93 (FIG. 6C).

Subsequently, the gapped plate 93 is processed by grinding or the like to a predetermined thickness, and then the apex glass 80 is molded on the apex portion (FIG. 6).
(D)).

After that, the gapped plate 94 is cut in a direction perpendicular to the magnetic film to obtain a plurality of bars 94, and then the bars 94 are cut to a predetermined thickness to form an I core as shown in FIG. A magnetic head 1 including 1A and a C core 1B is obtained.

The manufacturing method of the present invention is particularly characterized by a cutting step of cutting the gapped plate 93 into a bar shape in the above-described magnetic head manufacturing step. That is, according to the present invention, such a cutting process is divided into a plurality of times using a normal slicer.

The slicer that can be used in the present invention can be the slicer 10 provided with the disk-shaped blade 12 made of diamond abrasive grains described above with reference to FIG. Outer diameter (D) is 50 to 90
mm, the blade width (T) is 0.2 mm, and the length (E) of the exposed portion of the blade 12
Was 2.5 to 3.5 mm.

A gapped plate 93 obtained by the above method is shown in FIG. 1 (A), and its thickness (H) is 2 m.
m and the length (L) were 15 mm.

1 and 2 show a cutting process for cutting the gapped plate 93 into a bar shape. FIG. 1 shows a mode of cutting the unnecessary end portion 95 of the gapped plate 93, and FIG. 2 shows a cutting process for cutting out one bar 94 with a predetermined size.

According to the invention, the gapped plate 93
The cutting was performed in a plurality of times, and in the present example, it was performed in three times as shown in FIGS. That is, the cutting amount in the first cutting step is the cutting amount (H ₁ ), the cutting amount in the second cutting step is the cutting amount (H ₂ ), and the remaining amount is the cutting amount in the third cutting step (H ₃ ). In the present invention, in particular, when the workpiece is a non-magnetic ceramic substrate as in the present embodiment, the depth of cut is 1.0 mm.
Or less, preferably 0.9 mm or less.

When the thickness of the non-magnetic ceramic substrate is 2.0 mm as in this embodiment, the cut amount (H ₁ ) in the _first cutting step is 0.8 mm, Cutting depth (H ₂ ) in the _second cutting process is 0.8m
m, the rest (H ₃ ) is cut in the third cutting step.

The peripheral speed and feed rate of the blade 12 depend on the material of the work piece and the depth of cut, but the thickness is 1.2 to
In the case of non-magnetic ceramic substrate of about 3.0 mm,
Normally, the peripheral speed of the blade 12 is 2.5 to 3.0 m / sec, and the feed speed is 0.5 to 3.0 mm / sec. In this example, the blade 12 was rotated at a peripheral speed of 2.7 m / sec and the feed rate was 1.5 mm / sec.

In FIG. 3, the gaps at the positions of the first magnetic film M ₁ to the fourteenth magnetic film M ₁₄ of the four bars 94 when the gapped plate 93 is cut in three times as described above. The result of having measured depth (GD) is shown.

FIG. 4 shows a similar gapped plate 93.
Using the same slicer 10 as in the present embodiment, the first magnetic film M of the bar 94 when it is cut once in the conventional manner is used.
₁ shows the results of measurement of the gap depth (GD) in the 14 magnetic layer M ₁₄ position. In this case, the number of revolutions of the slicer 10 was the same as that of the present embodiment, but the feed rate was reduced to 0.5 mm / sec.

Comparing FIGS. 3 and 4, it can be seen that according to the present invention, cutting is performed with good straightness. Further, according to the present invention, as compared with the conventional single cutting, the blade 1
Since the load applied to 2 is made extremely small, the blade 1
It was also found that there is an advantage that the life of 2 is extended.

Example 2 In Example 1, in the thin film laminated magnetic head 1 as shown in FIG.
The principle of the present invention was applied when the gapped plate 93 was cut out into the bar 94 in the process of manufacturing the above. The present invention, however, laminates a magnetic thin film such as a Fe-Si-Al alloy magnetic film on the substrate. It can also be applied to a method of manufacturing a flying magnetic head having a thin film laminated head core configured as described above.

FIG. 10 shows an embodiment of the floating magnetic head. The floating magnetic head 5 of this embodiment includes a head core (head chip) 1, a dummy plate 3, and a housing 4. The head core 1 includes a pair of magnetic films M.
The core halves 1A and 1B having the gap spacer (g)
It is formed by joining through.

In manufacturing such a floating magnetic head 5, first, as shown in FIG. 11, in order to manufacture the head core 1, a CoO—NiO—Al film on which a magnetic film M has been formed is formed.
A non-magnetic ceramic substrate 2 such as a ₂ O ₃ substrate is produced, and after grooving and the like, it is laminated with a dummy substrate 3 made of a non-magnetic ceramic substrate to produce a magnetic film laminate 30.

Next, the magnetic film laminate 30 is cut out to cut out the first and second core plates 40, 40 '. FIG.
2, the first and second core plates 40,
40 'is subjected to a required grooving process, and then laminated with the grooved dummy block 4 to form a core / slider laminate 60.
Is prepared.

The core / slider laminated body 60 is cut in the direction orthogonal to the magnetic film M, and the core / slider laminated bar 6 is cut.
2 is cut out at a thickness (t). FIG. 13 shows a core slider laminate bar 62 that is somewhat enlarged from FIG.

This core / slider laminated bar 62 is shown in FIG.
As shown by the one-dot chain line in FIG. 3, the slider is cut parallel to the magnetic thin film layer M with a desired width W, and the slider with the head core, that is, the flying magnetic head 5 is manufactured.

According to the present invention, the core slider laminated body 6
The cutting of 0 is performed in multiple times. In this embodiment, the thickness (H) of the core / slider laminate 60 is 2 mm.
Therefore, as in the case of Example 1, the process was divided into three times. That is, the cutting amount (H ₁ ) in the _first cutting process is 0.8 mm, the cutting amount (H ₂ ) in the _second cutting process is 0.8 mm, and the remaining amount (H ₃ ) is the third.
It is cut in the second cutting step.

Also in this embodiment, the peripheral speed and the feed rate of the blade 12 are changed depending on the material of the work piece, the depth of cut, and the like. For example, the thickness (H) of the core-slider laminate 60 is 1.2. When it is set to about 3.0 mm, the peripheral speed of the blade 12 is usually 2.5 to 3.0 m / sec, and the feed speed is 0.5 to 3.0 mm / sec. In this embodiment,
The blade 12 was rotated at a peripheral speed of 2.7 m / sec and the feed rate was 1.5 mm / sec.

In the present embodiment as well, it was possible to obtain the same good straightness of cutting as in the first embodiment. Further, according to the present invention, it has been found that the load on the blade 12 is made extremely small as compared with the conventional single cutting, so that the life of the blade 12 is extended.

[0039]

As is apparent from the above description, in the method of manufacturing a magnetic head according to the present invention, the step of cutting a workpiece by a slicer having a disk-shaped blade made of diamond abrasive grains is divided into a plurality of steps. As it is configured,
It is possible to improve the straightness of the cutting process, improve the processing accuracy particularly when cutting the non-magnetic ceramic substrate in the magnetic head, and significantly improve the manufacturing yield. Since the cutting speed can be doubled because the cutting process is performed a plurality of times, the productivity becomes equivalent to that of the single cutting. Further, according to the present invention, the load applied to the blade is made extremely small as compared with the conventional single-cutting, so that there is an advantage that the life of the blade is extended.

[Brief description of drawings]

FIG. 1 is a perspective view illustrating a step of cutting a gapped plate into a bar shape according to the present invention.

FIG. 2 is a perspective view illustrating a step of cutting a gapped plate into a bar shape according to the present invention.

FIG. 3 is a graph showing variations in gap depth when a gapped plate is cut into bars according to the present invention.

FIG. 4 is a graph showing variations in gap depth when a gapped plate is cut into a bar shape by a conventional method.

FIG. 5 is a perspective view showing an example of a magnetic head.

FIG. 6 is an explanatory diagram showing a manufacturing process of the magnetic head.

FIG. 7 is a perspective view for explaining a step of cutting the gapped plate into a bar shape.

FIG. 8 is a front view showing a schematic configuration of a slicer.

FIG. 9 is a graph showing the relationship between the load applied to the slicer and the cut amount.

FIG. 10 is a perspective view showing an example of a floating magnetic head.

FIG. 11 is an explanatory diagram showing a manufacturing process according to an embodiment of a flying magnetic head.

FIG. 12 is an explanatory diagram showing a manufacturing process according to an embodiment of a floating magnetic head.

FIG. 13 is a perspective view for explaining a step of cutting out a slider with a head core from a core / slider laminated plate.

[Explanation of symbols]

1 magnetic head 2, 3, 4 non-magnetic ceramic substrate 5 floating magnetic head (slider with head core) 10 slicer 12 blade 60 core slider laminated body 62 core slider laminated bar 93 gapped plate 94 bar

Claims (4)

[Claims] 1. A method of manufacturing a magnetic head, comprising a step of cutting a work piece with a slicer equipped with a disk-shaped blade made of diamond abrasive grains during the step of manufacturing a magnetic head, wherein the step of cutting the work piece with the slicer is performed. A method of manufacturing a magnetic head, characterized in that the magnetic head is manufactured in a plurality of times. 2. The method of manufacturing a magnetic head according to claim 1, wherein when the object to be processed is a non-magnetic ceramic substrate, the amount of one cut in the cutting step is 1.0 mm or less. 3. The method of manufacturing a magnetic head according to claim 2, wherein the amount of one cut in the cutting step is 0.9 mm or less. 4. The nonmagnetic ceramic substrate is CoO.
A method of manufacturing a magnetic head according to claim 2 or 3, wherein the substrate is a NiO-Al ₂ O ₃ substrate.