JPH08263804A - Magnetic head and its production - Google Patents

Abstract

PURPOSE: To obtain magnetic head which is simple in structure, is less in number of parts and is inexpensively producible with simple stages and a process for producing this magnetic head. CONSTITUTION: This magnetic head has a first magnetic core half body 1 which consists of a flat planar magnetic material and is wound with a coil 4 and an annular second magnetic core half body 2 which consists of a flat planar magnetic material and has an aperture 2a to be fitted with the coil 4. A magnetic core is constituted by butting and joining these magnetic core half bodies 1, 2 in a thickness direction via a spacer 3 for forming a magnetic gap. The magnetic core half bodies 1, 2 are simple in shape structure and are inexpensively formable. The need for polishing the butt surfaces in the magnetic gap parts of the magnetic core half bodies 1, 2 is eliminated if the magnetic core half bodies 1, 2 are formed by using the flat planar magnetic materials having the surface accuracy meeting the tolerance of the magnetic gap width of the magnetic head to be reduced. The magnetic core is formed in a planar form and is holdable by one core holder 6. Such magnetic core contributes to a decrease in the number of parts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head for magnetically recording or reproducing information on a magnetic recording medium and a method for manufacturing the same, and particularly to a head element formed by winding a coil around a magnetic core having a magnetic gap. The present invention relates to an induction type magnetic head having a magnetic field and a manufacturing method thereof.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 4D, a magnetic head of this type has a pair of magnetic core halves 11 and 12 constituting a magnetic core as a magnetic circuit and a magnetic core in the magnetic circuit. A gap spacer 13 that forms a magnetic gap, a coil assembly 14 in which a coil for electromagnetic conversion is wound around a bobbin, and a terminal 15 for external connection that is implanted in the bobbin and that transmits and receives signals to and from the outside. A core holder 16 for positioning and holding the magnetic core at a predetermined position, and a magnetic shield case 17 for shielding external noise.

In the conventional conventional manufacturing method of this magnetic head, first, as shown in FIG.
Abutting surfaces 11a sandwiching the gap spacer 3 at the respective tip portions of the magnetic core halves 11 and 12 fixed to 6;
12a is ground with a predetermined surface accuracy (surface roughness, flatness) according to the tolerance of the magnetic gap width. Next, as shown in (b), the magnetic core halves 11 and 12 are butted against each other with the coil assembly 14 and the gap spacer 13 interposed therebetween, (c).
Adhesively fix as in. Furthermore, the assembly of (c) is replaced by (d)
As shown in FIG. 5, the tip end surface of the magnetic core having the magnetic gap formed by the gap spacer 13 is exposed to the opening (not shown) formed on the sliding surface of the case 17, and The case 17 is filled with resin and cured to fix the assembly. Then, the upper surface of the case 17 in the figure is used as a sliding surface for sliding contact with a magnetic recording medium (not shown), and is polished into a cylindrical shape to complete the magnetic head.

[0004]

However, the above-mentioned conventional example has the following drawbacks.

[0005] 1. The number of parts is large and the cost is increased.

2. Since the number of manufacturing steps is large, the cost is increased.

3. In the case of a multi-track head in which a plurality of head elements composed of a magnetic core and a coil assembly are arranged in parallel in the track width direction at a predetermined interval, it is difficult to obtain the track interval accuracy and the number of man-hours for adjusting the track interval increases, resulting in cost increase. Become.

4. Since the structure is complicated, it is difficult to manufacture a large number of heads at a time, that is, so-called a large number of heads are produced, and the cost is increased.

SUMMARY OF THE INVENTION An object of the present invention is to provide a magnetic head having a simple structure, a small number of parts, and a simple process which can be manufactured at low cost, and a manufacturing method thereof.

[0010]

In order to solve the above problems, according to the magnetic head of the present invention, a first magnetic core half body made of a flat plate magnetic material and having a coil wound around it, and a flat plate magnetic material are used. A magnetic core is formed by abutting and joining a ring-shaped second magnetic core half body made of a material and having an opening for fitting the coil in the thickness direction through a spacer for forming a magnetic gap. Adopted.

Further, according to the method of manufacturing a magnetic head of the present invention, a first core made of a flat magnetic material and corresponding to a plurality of the first magnetic core halves connected at a predetermined interval in the track width direction. And a flat magnetic material
A plurality of linked magnetic cores are obtained by joining a second core material corresponding to a plurality of linked magnetic core halves in the track width direction at predetermined intervals via a spacer for forming a magnetic gap. A method having steps was adopted.

Further, a manufacturing method is adopted in which the first and second magnetic core halves are formed by using a flat plate-shaped magnetic material having surface accuracy according to the tolerance of the magnetic gap width of the magnetic head to be manufactured. .

[0013]

According to the structure of the magnetic head of the present invention, the first
Since the second magnetic core half body is made of a flat magnetic material and has a simple shape structure, it can be formed easily and at low cost. Also,
Since the magnetic core composed of the flat first and second magnetic core halves is flat, it can be held by one core holder, and the number of parts can be reduced.

Further, at least one is included in the second magnetic core half body.
If one coil is wound, it is suitable for a head for both recording and reproduction and a bias signal application type head.

A plurality of second magnetic core halves are connected at predetermined intervals along the track width direction, and a plurality of independent first magnetic cores are provided for each of the plurality of second magnetic core halves. If the structure has a plurality of magnetic cores formed by joining core halves, an inexpensive multi-track head having a simple structure and a small number of parts can be formed.

Further, according to the former manufacturing method of the present invention, a plurality of magnetic cores connected to each other can be obtained by an extremely simple process, and the accuracy of the track spacing is between the first and second core materials. High accuracy can be easily ensured by the accuracy of forming the track, and the adjustment of the track interval becomes unnecessary. Further, by cutting the plurality of magnetic cores connected to each other into a predetermined number of magnetic cores, a predetermined number of magnetic cores can be obtained at a time, and a large number can be obtained.

Further, according to the latter manufacturing method of the present invention, it is possible to omit the step of polishing the abutting surfaces of the first and second magnetic core halves on the tip side abutting surfaces which sandwich the spacer for forming the magnetic gap.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment] FIG. 1 illustrates the structure and manufacturing method of a magnetic head according to the first embodiment of the present invention.

First, the structure of the magnetic head will be described. FIG.
1 and 2, reference numerals 1 and 2 are first and second magnetic core halves constituting a magnetic core as a magnetic circuit, and 3 is a gap spacer made of a foil-like non-magnetic material for forming a magnetic gap in the magnetic circuit, 4 is a coil for electromagnetic conversion, 5 is a terminal for external connection for exchanging signals with the outside, 6 is a core holder for fixing a magnetic core, and 7 is a magnetic shield case for shielding external noise. is there.

The magnetic core halves 1 and 2 are made of a flat magnetic material having a high magnetic permeability, the first magnetic core half 1 is formed in an elongated rectangular shape, and the second magnetic core half 2 is fitted with a coil 4. It is formed in a ring shape having an opening 2a for fitting. Further, the surface precision (surface roughness Rmax and flatness) of the surface of the flat magnetic material forming the magnetic core halves 1 and 2 depends on the tolerance of the magnetic gap width due to the thickness of the gap spacer 3, Specifically, the surface roughness Rmax is 1/5 or less, preferably 1/10 or less of the magnetic gap width, and the flatness is 1/5 or less, preferably 1/10 of the magnetic gap width.
Below. The flat magnetic material may be a single plate or a laminated plate.

The coil 4 may be wound around a bobbin (not shown), and the terminal 5 may be integrally embedded in the bobbin.

Next, the manufacturing method will be described. First, as described above, the first and second magnetic core halves 1 and 2 are formed from a flat plate-shaped magnetic material whose surface accuracy depends on the tolerance of the magnetic gap width of the manufactured head.

Next, after the coil 4 is wound around the first magnetic core half body 1, as shown in FIG. 1A, the gap spacers 3 are sandwiched between the first and second magnetic core half bodies. The 1 and 2 are abutted in the thickness direction, and are joined and fixed as shown in (b) by spot welding, laser welding, or resin bonding. At this time, in the case of welding, it is performed at a portion to be removed by grinding the sliding surface of the magnetic head later.

Next, the head element composed of the magnetic core and the coil 4 in which the magnetic core halves 1 and 2 of (b) are joined is positioned on the core holder 6 as shown in (c) and fixed by adhesion.
At this time, the coil 4 protruding downward in the drawing of the magnetic core half body 2
This portion is fitted into the opening 6a formed in the core holder 6.

Next, as shown in (d), the terminal 4 of the coil 4 is
After winding and connecting each of a to each of the terminals 5, the assembly of the head element and the core holder 6 is fitted into the magnetic shield case 7. The surface of the case 7 on the front side in the drawing is a sliding surface that comes into sliding contact with a magnetic recording medium (not shown).
The opening 7a formed in this sliding surface faces the tip end surface where the magnetic gap is formed by the gap spacer 3 of the head element. Then, after filling the case 7 with resin or the like to fix the assembly of the head element and the core holder 6, the sliding surface is finished to complete the magnetic head.

In the above process, the magnetic core halves 1 and 2 are first joined together. However, after the magnetic core half 2 is joined to the core holder 6, the magnetic core half 1 is magnetized with the gap spacer 3 interposed therebetween. It may be bonded to the core half 2. Further, the magnetic gap spacer 3 may be formed on the abutting surface of the magnetic core half body 1 or 2 by screen printing, surface treatment (parylene processing, plating) or the like, instead of the foil shape.

According to this embodiment, since the magnetic core halves 1 and 2 are made of flat magnetic material and have a simple shape structure, they can be formed easily and inexpensively. Further, by making the surface accuracy of the surface of the flat magnetic material according to the tolerance of the magnetic gap width, it is possible to omit the step of polishing the abutting surfaces of the magnetic core halves 1 and 2 that sandwich the gap spacer 3. You can Further, since the magnetic core composed of the flat magnetic core halves 1 and 2 has a flat shape, it can be held by one core holder 6, and the number of parts can be reduced by one compared with the conventional example having two core holders.

Thus, the number of parts is reduced, the manufacturing process is simplified, and the cost can be greatly reduced.

[Second Embodiment] Next, a method for manufacturing a multi-track head will be described as a second embodiment with reference to FIG.

In FIG. 2, reference numeral 21 denotes a first core material, which is formed from the above-mentioned flat plate-shaped magnetic material in the shape of a comb tooth. The first magnetic core half body 1 described above is arranged along the track width direction. A plurality of them are arranged in parallel at a predetermined interval and are connected at the tip end side (the magnetic gap side).

Reference numeral 8 is a coil assembly in which the coil 4 is wound around a coil bobbin and a terminal 5 for connecting the end of the coil 4 is implanted. The coil assembly 8 is fitted to each of the first magnetic core half bodies 1 of the core member 21.

Reference numeral 22 denotes a second core material, which is made of the above-mentioned flat plate-shaped magnetic material and has the above-mentioned second magnetic core half body 2.
Are arranged in parallel along the track width direction at predetermined intervals and are arranged side by side and connected. The second core material 22 is fixed on the elongated core holder 6.

Then, as shown on the right side of FIG. 2, the positions of the magnetic core halves 1 and 2 are aligned with each other, and the gap spacer 3 is sandwiched between the tips of the magnetic core halves 1 and 2, so that the first core member 21 is placed in the second The core material 22 is overlaid and positioned, and is bonded and fixed by adhesion or the like. As a result, a multi-track head element including a plurality of magnetic cores and a plurality of coil assemblies 8 connected to each other is formed.

Subsequently, the assembly of the core materials 21 and 22 and the core holder 6 is fitted in a magnetic shield case (not shown), the tip end is exposed to the opening of the sliding surface of the case, and the case is filled with resin or the like. To fix the assembly.

Next, after the connecting portion 21a at the upper end in FIG. 2 of the first core material 21 exposed from the opening of the sliding surface of the case is cut and removed, polishing of the sliding surface of the case is finished. Processing is completed to complete the multi-track head.

In the completed multi-track head, the first magnetic core half body 1 of each magnetic core becomes independent by cutting the connecting portion 21a, but the second magnetic core half bodies 2 are separated from each other. It remains connected. However, there is little influence of crosstalk between adjacent tracks at the time of recording and reproducing, and there is no problem.

As described above, a multi-track head having a simple structure and a small number of parts can be manufactured at low cost by a simple process. In the manufactured head, the track interval can be easily ensured with high accuracy by the accuracy of forming the core materials 21 and 22, and the adjustment of the track interval becomes unnecessary.

The core materials 21 and 22 are the number of magnetic core halves 1 or 2 which is more than twice the number of tracks of the head to be manufactured.
And the core holders 21 and 22 and the core holder 6 are assembled in the above process, that is, a plurality of track head elements including a plurality of coupled magnetic cores and a plurality of coil assemblies 8 and a core holder 6 are formed. After that, by cutting the assembly at the connecting portion between the magnetic cores for each magnetic core having the number of tracks of the head to be manufactured, a plurality of heads having a predetermined number of tracks can be manufactured at one time. In particular, if each magnetic core is cut, it is possible to easily take a large number of heads for one track, and the cost can be reduced.

By the way, the core members 21 and 22 may be formed as those corresponding to a plurality of magnetic core halves 1 and 2 connected at the rear end side (the side opposite to the magnetic gap).

[Third Embodiment] FIG. 3 shows the structure of the head element of the magnetic head of the third embodiment. In the magnetic head of the present embodiment, the magnetic core is formed by joining magnetic core halves 1 and 2 made of a flat magnetic material as in the first embodiment, but the coil 4 is wound around the magnetic core half 1. In addition,
A coil 9 is also wound around the magnetic core half body 2. Each of the terminals 4a and 9a of the coils 4 and 9 is a terminal holding member 10
Are connected to each of the four terminals 5 implanted in the. The terminal holding member 10 may be an independent member or a member integrally formed with a bobbin around which the coil 4 or 9 is wound.

The head of this embodiment is used, for example, as a head for both recording and reproduction, and one of the coils 4 and 9 is for recording and the other is for reproduction, and the number of turns is suitable for each.
The thickness can be selected.

Further, the head of this embodiment can be used as a bias signal applying head such as a magnetic bar code reading head, and one of the coils 4 and 9 can be used for reading and the other for bias signal.

It is also possible to wind two coils around the magnetic core half body 2.

[0045]

As is apparent from the above description, according to the magnetic head and the method of manufacturing the same of the present invention, the magnetic core is formed by the magnetic core half body made of the flat magnetic material, and the structure is simple and the number of parts is small. The manufacturing process can be simplified by omitting the step of polishing the abutting surface of the magnetic gap portion, and a large number of individual pieces can be obtained, resulting in a significant cost reduction. Further, when the multi-track head is configured, the excellent effects such as the accuracy of the track interval can be easily made high and the adjustment of the track interval is unnecessary can be obtained.

[Brief description of drawings]

FIG. 1 is a perspective view showing a structure and a manufacturing method of a magnetic head according to a first embodiment of the invention.

FIG. 2 is an explanatory diagram illustrating a manufacturing process of a multi-track head according to a second embodiment.

FIG. 3 is a front view showing the structure of a head element of a third embodiment.

FIG. 4 is an explanatory diagram showing a structure and a manufacturing process of a conventional magnetic head.

[Explanation of symbols]

 1, 2 Magnetic core half body 3 Gap spacer 4,9 Coil 5 Terminal 6 Core holder 7 Magnetic shield case 8 Coil assembly 21, 22 Core material

Claims (6)

[Claims] 1. A first magnetic core half made of a flat magnetic material around which a coil is wound, and a ring-shaped second magnetic core made of a flat magnetic material and having an opening into which the coil is fitted. A magnetic head having a magnetic core formed by abutting and joining a half body in the thickness direction through a spacer for forming a magnetic gap. 2. At least one in said second magnetic core half.
The magnetic head according to claim 1, wherein a single coil is wound. 3. A plurality of the second magnetic core halves are connected at a predetermined interval along the track width direction, and the plurality of the first magnetic core halves are independent of each of the plurality of second magnetic core halves. 3. The magnetic head according to claim 1, further comprising a plurality of magnetic cores formed by joining the magnetic core halves. 4. A first magnetic core material made of a flat magnetic material and corresponding to a plurality of the first magnetic core halves according to claim 1 connected at a predetermined interval in the track width direction, and a flat magnetic material. The second magnetic core half body according to claim 1 is joined to the second core material corresponding to a plurality of second magnetic core halves connected at a predetermined interval in the track width direction via a spacer for forming a magnetic gap. And a step of obtaining a plurality of magnetic cores connected to each other. 5. The method of manufacturing a magnetic head according to claim 4, further comprising the step of cutting the plurality of connected magnetic cores into a predetermined number of magnetic cores. 6. The method of manufacturing a magnetic head according to claim 1, wherein the magnetic head has a flat surface magnetic surface accuracy according to a tolerance of a magnetic gap width of the magnetic head to be manufactured. A method of manufacturing a magnetic head, characterized in that the first and second magnetic core halves are formed using a material.