JP3153917B2 - 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 used in, for example, a floppy disk drive.

[0002]

2. Description of the Related Art Conventionally, as this type of magnetic head, for example, the one shown in FIG. 6 is known. That is,
As shown in FIG.
1, a head core 12 is joined by glass fusion. As shown in FIG. 7, the head core 12 is a tunnel erase type core, and is an R / W (read / write) core 12 arranged on the upstream side in the disk rotation direction.
a and an erase core 12b arranged on the downstream side. When manufacturing such a magnetic head 12, first, the R / W core 12 a is
Then, an R / W core 12a and an erase core 12b are formed using the secondary fused glass 14.
To join. Further, the head core 12 configured as described above is bonded to the guard members 10 and 1 by the tertiary fusion glass 15.
Join to 1. In this case, the fused glass whose melting temperature is gradually lowered is used so as not to affect other fused glass at the time of glass joining.

[0003]

However, in the case of such a conventional example, since the fusion temperature at the time of each joining is close, 2
The primary and secondary fusion glasses 13 and 14 are melted at the time of the next and third fusion, so that the gap lengths of the magnetic gaps g ₁ and g ₂ of the R / W core 12a and the erase core 12b are increased, There has been a problem that the gap between the gaps g ₁ and g ₂ is widened and the product yield is deteriorated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points of the prior art, and an object of the present invention is to provide a magnetic head capable of preventing a gap length and a gap interval of a magnetic gap from being increased in a manufacturing process. It is in.

[0005]

According to the present invention, a head core 3 formed by joining a read / write core 3a and an erase core 3b, for example, as shown in FIG.
In the magnetic head having the guard members 1 and 2 joined to the head core 3, the joining surface between the read / write core 3a and the erase core 3b, the head core 3 and the guard members 1
At least one of the bonding surfaces with the second metal layer 2 is bonded by low-temperature thermal diffusion using the first metal layer 6 and the second metal layer 7 made of a noble metal.

[0006]

According to the present invention having such a configuration, at least one of the joining surface between the read / write core 3a and the erase core 3b and the joining surface between the head core 3 and the guard members 1 and 2 is formed of the first metal layer 6 and the noble metal. The glass used for the primary fusion of the read / write core 3a and the erase core 3b does not melt during the secondary and tertiary fusion because the second metal layer 7 is bonded by low-temperature thermal diffusion. .

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the magnetic head according to the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show this embodiment. FIG. 1 shows a core of a magnetic head, and FIG. 2 shows the entire configuration of the magnetic head. The magnetic head according to the present embodiment is applied to a floppy disk drive, and includes two guard members 1 and 2 and a head core 3 sandwiched and joined therebetween, as shown in FIG.

The guard member 1 has a disk contact surface 1a for contacting a floppy disk (not shown) and a groove 1b. As guard material 1,
For example, nonmagnetic barium titanate, potassium titanate, or nonmagnetic ferrite can be used. The guard members 1 and 2 and the head core 3 are joined by a low-temperature thermal diffusion joining method described later. Head core 3, as shown in FIG. 1, R / W core (so-called R / W head elements) 3a and Irezukoa is composed of a (so-called erase head elements) 3b, half each of the pair core e.g. ferrite core half The body is formed by joining the first fused glass 4. As a result, magnetic gaps G ₁ and G ₂ are formed. On the other hand, a first layer film 5, a second layer film 6, and a third layer film 7, which will be described later, are provided on each joint surface of the R / W core 3a and the erase core 3b.
Are formed and joined by a low-temperature thermal diffusion joining method. The distance a between the bonding surfaces is, in the magnetic head for two megabytes 70μm position, in the magnetic head for 4 megabytes is 20μm position.

Next, the manufacturing method of this embodiment will be described with reference to FIG.

First, similarly to the conventional example, the primary fused glass 4
To produce an R / W core 3a and an erase core 3b. In this case, the glass fusing temperature is 600 ° C.

Next, the first layer film 5 is formed on the bonding surface of the R / W core 3a and the erase core 3b by a vacuum film forming method such as sputtering, ion plating, or vapor deposition.
To form In this case, the first layer film 5 is made of SiO ₂ , Al
_It consists of non-magnetic oxides such as ₂ O ₃ , nitrides and carbides.

The first layer film 5 is formed for the following reason. That is, the R / W core 3a and the erase core 3b
If there is no gap between them at a certain distance (several tens of μm), a magnetic gap is formed, which acts as a reproducing gap at the time of off-track, so that the off-track characteristic deteriorates. Therefore, R / W core 3
The first layer film 5 described above is formed in order to secure the distance a between the bonding surfaces of the a and the erase core 3b. Therefore, when the off-track characteristic of the magnetic head does not cause any problem in practical use, or when the second layer film 6 and the third layer film 7 described later only use this distance a
Is not necessary when the first layer film 5 can be secured.

Next, a second layer film 6 is formed on each first layer film 5 by a vacuum film forming method in the same manner as the first layer film 5. This second
The layer film 6 is formed to secure the adhesion between the first layer film 5 and the third layer film 7, and is formed of Ti, Mo, W, Mn, F
e, Co, Ni or a metal selected from the group consisting of these alloys, and has a thickness of 50 to 1000 °.

Further, on each second layer film 6, a first and a second
Similarly to the layer films 5 and 6, the third layer film 7 is formed by a vacuum film forming method. The third layer film 7 is made of a noble metal selected from Au, Ag, Pt, and Pd, and has a thickness of 100 to 200.
0 °.

Thereafter, as shown in FIG. 3B, the third layer film 7 is formed.
Butt each other, 1 kgf / cm ^{2 to} 1000
The R / W core 3a and the erase core 3b are joined by applying a pressure of Kgf / cm ^{2 and} performing a heat treatment at a temperature of 50 ° C. to 500 ° C. Here, for example, when Au is used for the third layer film 7, by applying a pressure of 100 kgf / cm ² and performing a heat treatment at a temperature of 250 ° C. for 1 hour, a sufficient strength exceeding the bonding strength of glass can be obtained. Strong bonding is enabled.

Further, as shown in FIG.
The second layer film 6 and the third layer film 7 are formed on the bonding surface of the head core 3 and the bonding surfaces of the head core 3 respectively, and the guard materials 1 and 2 are butted against the head core 3 under the same conditions. And heat treatment is performed. Thereby, the head core 3 and the guard members 1 and 2 are firmly joined.

In this embodiment having such a configuration,
The joining between the R / W core 3a and the erase core 3b and the joining between the head core 3 and the guard materials 1 and 2 are performed at a low temperature (50 ° C. to 50 ° C.).
(0 ° C.), the primary fused glass 4 does not melt out, and the magnetic gaps G ₁ and G _{2 of} the R / W core 3a and the erase core 3b are widened, and the gap between them is widened. There is no. Therefore, according to the present embodiment, there is an effect that the yield of products is improved. still,
The bonding temperature in the low-temperature thermal diffusion bonding method of this embodiment is Au,
Since it is much lower than the melting point of metal such as Ti, it does not affect the joining between the R / W core 3a and the erase core 3b when joining the head core 3 and the guard materials 1 and 2.

Further, according to this embodiment, the thermal stress generated in the head core 3 and the reaction between the glass and the core material can be reduced, so that a magnetic head having high characteristics can be obtained.

Further, according to the magnetic head of this embodiment,
Compared with a conventional example in which bonding is performed by glass fusion, the weather resistance is excellent and a high-strength bonding is possible.

FIG. 4 shows a main part of another embodiment of the present invention. As shown in FIG.
The first layer film 5 is formed only on the / W core 3a, and the first layer film 5 is not formed on the erase core 3b.

FIG. 5 shows a main part of still another embodiment of the present invention. In this embodiment, the R / W core 3a
Glass, Al ₂ O ₃ , Ti between
A non-magnetic thin plate 8 made of BaO ₃ , CaTiO ₃ or the like is arranged, and the R / W core 3a, the erase core 3b, and the thin plate 8
The above-mentioned second layer film 6 and third layer film 7 are formed on each of the bonding surfaces.

According to these embodiments, the length of the secondary bonding portion, that is, the distance a between the bonding surfaces of the R / W core 3a and the erasing core 3b can be adjusted according to the type of the magnetic head, and furthermore, the rigidity can be improved. A joint can be obtained. Other configurations and operations are the same as those of the above-described embodiment, and thus detailed description will be omitted.

In the above-described embodiment, the magnetic head of the tunnel erase type has been described as an example. However, the present invention is not limited to this. For example, secondary and tertiary fusion such as a preceding erase type is required. Can be applied to all magnetic heads.

Further, in the above embodiment, the R / W core and the erase core, and the head core and the guard material are joined by the above-described low-temperature heat diffusion method. However, the present invention is not limited to this. Either of these may be joined by the low-temperature thermal diffusion method described above. Further, when forming the gap between the R / W core and the erase core, the bonding may be performed by the above-described low-temperature thermal diffusion method.

[0026]

As described above, according to the present invention, at least one of the joining surface between the read / write core and the erase core and the joining surface between the head core and the guard material are the first metal layer and the second metal layer made of a noble metal. Therefore, it is possible to prevent the gap length and gap interval of the magnetic gap from being increased in the manufacturing process, thereby improving the product yield.

[Brief description of the drawings]

FIG. 1 is a front view showing a configuration of a main part of an embodiment of the present invention.

FIG. 2 is a front view showing the entire configuration of the embodiment.

FIG. 3 is an explanatory view showing a manufacturing method of the embodiment.

FIG. 4 is a front view showing a configuration of a main part of another embodiment.

FIG. 5 is a front view showing a configuration of a main part of still another embodiment.

FIG. 6 is a front view showing the entire configuration of a conventional example.

FIG. 7 is a front view showing a configuration of a main part of a conventional example.

[Explanation of symbols]

 1, 2 guard material 3 head core 3a R / W core 3b erase core 5 first layer film 6 second layer film 7 third layer film

────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yoichi Inmaki 6-5-6 Kita Shinagawa, Shinagawa-ku, Tokyo Inside Sony Magne Products Co., Ltd. (72) Inventor Kaoru Aoki 6-chome Kita-Shinagawa, Shinagawa-ku, Tokyo No. 5-6 Inside Sony Magne Products Co., Ltd. (56) References JP-A-63-228406 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G11B 5/265

Claims (1)

(57) [Claims] 1. A magnetic head having a head core formed by joining a read / write core and an erase core, and a guard material joined to the head core, wherein a joining surface between the read / write core and the erase core, At least one of the joining surfaces with the guard material is the first
A magnetic head joined by low-temperature thermal diffusion using a metal layer and a second metal layer made of a noble metal.