JP3413499B2 - Manufacturing method of magnetic head - Google Patents

Description

Detailed Description of the Invention

[0001]

The present invention relates to a method of <br/> manufacturing a magneto-optical recording magnetic head used in the magneto-optical recording method of magnetic field modulation system.

[0002]

2. Description of the Related Art Conventionally, as a magneto-optical disk as a magneto-optical recording medium, as shown in FIG. 4, a magnetic head for magneto-optical recording for performing signal recording by a magnetic field modulation method is generally known. Here, symbol S is a slider made of non-magnetic ceramic or the like.
Is a buoyancy force given by the air flow that accompanies the high-speed rotation of the disk, and it has the aerodynamic shape required to fly while maintaining a small gap between the magnetic head and the disk. Has a face.

A U-shaped magnetic core C made of a magnetic material, for example, ferrite is disposed at the rear end of the slider S, and is bonded to the slider S by using glass G as a bonding material. The coil W is wound around the magnetic core C.

Conventionally, such a magnetic head for magneto-optical recording is manufactured according to the following process sequence as shown in FIGS. 5 (a) to 5 (d). (First Step) As shown in FIG. 5A, a magnetic core mounting groove P1 and a coil winding groove P2 are formed as a housing portion H at the rear end of the slider S made of ceramics.
It is formed by machining or press molding. At the same time, in order to improve the air floating characteristic of the slider S, the groove P3 may be formed on the bottom surface thereof. In this case, the thickness t of the lower eaves portion of the housing portion is set to 0.2 mm. (Second step) As shown in FIG. 5B, a magnetic core C of a U-shape made of ferrite is disposed in the housing H with the open end of the magnetic core C facing the bottom surface of the slider S. It is arranged in the groove P1 for bonding and is bonded by means of glass bonding. (Third step) As shown in FIG. 5C, the slider S
The bottom surface of is subjected to mirror polishing so that it is sufficiently smooth to be suitable for air levitation and has a sufficiently small surface roughness. (Fourth Step) As shown in FIG. 5D, the coil W is wound around the magnetic core C using the coil winding groove P2. At this time, the height h from the bottom surface of the slider S to the coil W
Is regulated by the lower eaves of the housing H, and is equal to the thickness t of the lower eaves.

By the way, in recent years, with respect to such a magnetic head for magneto-optical recording, there is an increasing demand for high speed signal recording. In order to meet such a demand, the magnetic head has its inductance. Needs to be reduced and the efficiency of magnetic field generation needs to be increased. As an effective realization means thereof, the coil W is replaced by the magnetic core C.
It has been attempted to provide the magnetic pole end closer to the magnetic pole end, that is, closer to the disk.

FIG. 6 is presented to explain this, and the height h from the bottom surface of the slider S to the coil W, the inductance value of the magnetic head, and the magnetic field generation efficiency (generation per 1 mA of recording current). This is the result obtained by experiment for the relationship with the magnetic field strength). As is clear from the figure, it is understood that the smaller the height h, the smaller the inductance value and the higher the magnetic field generation efficiency, which is suitable for high-speed signal recording.

[0007]

Under the circumstances, it is necessary to reduce the height h from the bottom surface of the slider S to the coil W, but the height h is the lower eaves of the housing portion H of the slider S. It is regulated by the part and is equal to the thickness t, so the thickness t is small, and preferably 0.0
It is necessary to make it about 5 mm. However, when t is smaller than about 0.2 mm, the housing portion H
The mechanical strength of the lower eaves part is insufficient, and during the above-mentioned magnetic head manufacturing process, during the formation of the housing part H in the first process, or during the use of the magnetic head, particularly the loading and unloading operations. There is a problem that the eaves portion is damaged by the impact generated during the seek operation. For this reason, the frequency of the recording signal is about 10 MHz at the maximum, and it is impossible to realize a magnetic head that meets the demand for higher signal recording speed.

[0008]

In order to solve the above-mentioned problems of the prior art, the present invention provides a first step of forming a housing portion on a slider made of a non-magnetic material, and a magnetic step on the housing portion. A second step of disposing the core,
The third step of winding the coil around the magnetic core, the fourth step of providing the reinforcing member on the housing part, and the bottom surface facing the disk of the slider are machined so that the height to the coil becomes a predetermined value. consists of a fifth step of forming a, is intended to provide a method of manufacturing a magnetic head, characterized in that to produce the magnetic head I follow the above sequence of steps.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method of manufacturing a magnetic head according to the present invention will be specifically described below with reference to the drawings. The magnetic head of the present invention is manufactured according to the following process sequence, as shown in FIGS.

(First Step) As shown in FIG. 3 (a),
At the rear end of the slider S made of ceramic, a magnetic core arranging groove P1 and a coil winding groove P are provided as a housing portion H.
2 and are provided. In this case, the housing part H is formed by machining or press molding. Housing part H
The thickness t of the lower eave portion is set to 0.2 to 0.3 mm so as to have a mechanical strength that does not damage during processing.

(Second step) As shown in FIG. 3 (b),
The U-shaped magnetic core C made of ferrite is placed in the magnetic core arranging groove P1 of the housing portion H of the slider S, and bonded by glass bonding means.

(Third step) As shown in FIG.
The coil W is wound around the magnetic core C by using the coil winding groove P2 provided in the slider S.

(Fourth step) As shown in FIG. 3 (d),
A reinforcing member R is provided in the coil winding groove P2. The reinforcing member R may be, for example, an epoxy resin or the like filled in the groove for coil winding, and in particular, when an inorganic filler such as glass or alumina is mixed in the resin to increase the mechanical strength. It is effective.

(Fifth Step) As shown in FIG. 1 (e),
After the bottom surface of the slider S is formed by mechanical processing such as grinding so that the thickness t of the lower eaves of the housing portion H is about 0.05 mm, it is suitable for air levitation.
Mirror finishing is performed so that the surface is sufficiently smooth and the surface roughness is sufficiently small. From bottom of slider S to coil W
The height h up to is regulated by the lower eaves of the housing H and is equal to the thickness t thereof, and therefore is 0.05 mm.

Here, in order to improve the air levitation characteristics of the slider S simultaneously with the processing of the bottom surface of the slider S,
The groove P3 may be formed on the bottom surface of the slider S.

FIG. 1 is a perspective view of a magnetic head manufactured according to the above-described process sequence.

FIG. 2 shows another embodiment of the magnetic head according to the present invention. In this example, the reinforcing member R is a non-magnetic material such as glass or ceramic, and the spacer SP is made of a material having a coefficient of thermal expansion close to that of the ceramic forming the slider S, and the spacer SP is fixed in the coil winding groove. And an adhesive B to be used. The spacer SP is shaped to fit into the coil winding groove, as shown in FIG.

In the case of this embodiment, in particular, by making the thermal expansion coefficients of the spacer SP and the slider S substantially equal to each other, it is possible to avoid the occurrence of stress due to temperature change, and to improve the mechanical strength of the lower eaves of the housing H. Can be maintained.
Further, in particular, by forming the spacer SP with a material having high thermal conductivity, the spacer SP serves as a heat dissipation member so as to effectively dissipate heat generated when a recording current of high frequency is supplied to the magnetic head. You can also combine. Suitable materials for such spacers SP are metals such as copper and aluminum, and ceramics such as SiC and BN.

[0019]

As described above, in the method of manufacturing the magnetic head according to the present invention, the first step of forming the housing portion on the slider made of a non-magnetic material and the second step of disposing the magnetic core in the housing portion. Step, the third step of winding the coil around the magnetic core, the fourth step of providing the reinforcing member on the housing part, and the disk of the slider facing the height of the coil to a predetermined value. And a fifth step of forming the bottom surface by machining, and the magnetic head is manufactured in accordance with the above-mentioned order of steps.

Therefore, in order to reduce the height from the bottom of the slider to the coil, which is a problem in the prior art, the thickness of the lower eaves of the slider housing should be less than 0.2 mm. If the value is too small, the mechanical strength of the lower eaves part of the housing part will be insufficient, and when forming the housing part when manufacturing the magnetic head, or when using the magnetic head, especially when loading, unloading or seeking. The problem that the eaves part is damaged by the generated impact is solved, and thus the height from the bottom surface of the slider to the coil is, for example, smaller than 0.2 mm, preferably 0.05 mm. It will be possible. As a result, the inductance of the magnetic head is reduced,
Further, since the magnetic field generation efficiency is increased, the maximum frequency of the recording signal can be set to 12 to 15 MHz, and signal recording can be realized at a higher speed than in the past.

In particular, when a spacer made of a material having substantially the same coefficient of thermal expansion as that of the slider is used as the reinforcing member, stress due to temperature change is not generated, so that the mechanical strength of the housing portion is more effective. Can be maintained. When a spacer made of a material having a high thermal conductivity is used as the reinforcing member, the spacer is used as a heat radiating member so as to effectively radiate heat generated when a recording current having a high frequency is supplied to the magnetic head. Can also be used as

[Brief description of drawings]

FIG. 1 is a schematic view of a magnetic head according to the present invention.

FIG. 2 is a schematic view of a magnetic head according to another embodiment.

FIG. 3 is a process drawing of a method of manufacturing a magnetic head according to the present invention.

FIG. 4 is a schematic view of a conventional magnetic head.

FIG. 5 is a process diagram of a conventional magnetic head manufacturing method.

FIG. 6 is a graph showing the relationship between the height from the bottom surface of the slider to the coil, the inductance, and the magnetic field generation efficiency.

[Explanation of symbols]

S slider C magnetic core W coil R reinforcement member SP spacer B adhesive

Claims (3)

(57) [Claims] 1. A first step of forming a housing portion on a slider made of a non-magnetic material, a second step of disposing a magnetic core in the housing portion, and a third step of winding a coil around the magnetic core. Step, a fourth step of providing a reinforcing member on the housing part, and a fifth step of forming the bottom surface of the slider facing the disk by machining so that the height to the coil becomes a predetermined value. consists of a process, a method of manufacturing the magnetic head is characterized in that to produce a magnetic head according to the above process sequence. The method according to claim 2, wherein said reinforcing member, the manufacture of the magnetic head according to claim 1, the thermal expansion coefficient characterized in that it contains substantially equal consisting material spacer and a non-magnetic material constituting the slider Method. 3. The method of manufacturing a magnetic head according to claim 1, wherein the reinforcing member includes a spacer made of a material having high thermal conductivity.