JPH0421922B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a magnetic head and a method for manufacturing the same, and particularly relates to a magnetic head that is small, has high gap accuracy, and is inexpensive, and a method for manufacturing the same. be.

[Background of the invention]

The structure of a conventional magnetic head and its manufacturing method will be explained with reference to FIGS. 1 to 3.

A box-shaped hold case 1 with one side open is provided with the required number of grooves 3 having a substantially concave side surface.
The first magnetic cores 2 are press-fitted into the grooves 3 to position and fix them. This first core 2
In addition to the above-mentioned fixing method, for example, a method of providing an insert member (not shown) in the hold case 1 and fixing the first magnetic core 2 to the hold case 1 via this insert member, a method of fixing the first magnetic core 2 to the hold case 1 using an adhesive, etc. 2 to the hold case 1 directly.

The second magnetic core 4 is positioned and fixed in the other hold cases 1a in the same manner as described above. Next, the abutting surface 2a of the first magnetic core 2 and the abutting surface 4a of the second magnetic core 4 are polished, and a coil 5 is wound around either one of the first and second magnetic cores 2 and 4. Coil bobbin 7 provided with terminal 6
Install. Next, the first magnetic core 2 fixed to the hold case 1 and the second magnetic core 4 fixed to the hold case 1a are brought into contact with each other via the gap plate 8 on the tape sliding surface side. Thereafter, the hold case 1 and the hold case 1a are joined and fixed to each other by fitting a pair of elastic press members 9 having substantially U-shaped side surfaces.

The magnetic head structure A assembled in this way is inserted into a shield case (not shown), and the magnetic head structure A is fixed in the shield case with adhesive or synthetic resin. The assembly of the magnetic head was completed by polishing the magnetic tape sliding surfaces of the cores 2 and 4.

[Problem that the invention seeks to solve]

Since this conventional magnetic head structure A uses two hold cases 1 and 1a as shown in FIG. 3, the width B of the magnetic head structure A is
This is determined by the length of the holding member 9 that fixes the pair of hold cases 1 and 1a, and as long as this conventional magnetic head structure is adopted, there is a limit to miniaturization.

Furthermore, in order to provide grooves 3 for fixing the first and second magnetic cores 2 and 4 in a part of the box-shaped hold cases 1 and 1a, the mold for manufacturing the hold cases 1 and 1a becomes complicated. Moreover, it is difficult to ensure dimensional accuracy.

Further, in the structure using the insert member described above, not only the number of parts increases, but also the first and second magnetic cores 2,
4 is fixed by the holding member 9, the pressing force of the abutting portions 2a, 4a of the first and second magnetic cores 2, 4 is uncertain.

Furthermore, the method of fixing the first and second magnetic cores 2, 4 to the hold cases 1, 1a using the adhesive described above has the disadvantage that it is susceptible to the adverse effects of expansion and contraction of the adhesive.

Further, in the method for manufacturing the magnetic head structure A, the abutting portions 2a and 4a of the first and second magnetic cores 2 and 4 are assembled in the hold cases 1 and 1a.
As a result, in a magnetic head constructed by assembling a plurality of magnetic cores in a hold case, it is difficult to achieve flatness accuracy of the abutting portions, and the gap accuracy is unstable.

Furthermore, a magnetic head such as that described in, for example, Japanese Utility Model Application Publication No. 48-30619 has been proposed. In this magnetic head, a first magnetic head element is composed of a pair of pole pieces arranged to face each other with a gap material interposed therebetween, and a coil piece having a U-shaped planar shape and having a coil wound therebetween. Further, a second magnetic head element is composed of a pair of pole pieces that are similarly arranged to face each other with a gap material in between, and a coil piece that has a U-shaped planar shape and has a coil wound therebetween.

Next, the first magnetic head element and the second magnetic head element are arranged vertically through a shield plate and two holding members, and between the upper coil piece end and the lower coil piece end. , a substantially U-shaped elastic member is fitted onto the outside. Then, by utilizing the vertical tightening force of this elastic member, the bonded state between the end of each pole piece and the end of the coil piece is ensured, and the adhesive is infiltrated into this joint, allowing each pole The piece and the coil piece are glued together.

However, this magnetic head has the following problems because the clamping force of the elastic member acts in the thickness direction of the magnetic head element. In other words, if the parallelism of the end of the pole piece, the end of the coil piece, the shield plate, and the holding member are not accurately ensured, the magnetic head element will be damaged when tightened vertically with the elastic member as described above. If one end of the operating gap is too close to open,
Therefore, the desired gap accuracy cannot be ensured.

In addition, since there is no force pushing the pole pieces toward the operating gear, when the magnetic head assembly mentioned above is buried in synthetic resin to protect it, the shrinkage force caused by the cooling of the synthetic resin is applied to the pole pieces. The actuating gear may act on the coil piece and the actuating gap may become too close to opening, which also makes it impossible to ensure gap accuracy.

SUMMARY OF THE INVENTION An object of the present invention is to provide a magnetic head that eliminates the above-mentioned drawbacks of the prior art, is compact, easy to assemble, and can accurately ensure the gap accuracy of the magnetic core, and a method for manufacturing the same.

[Means for solving problems]

In order to achieve the above object, the magnetic head of the present invention includes one flat plate-shaped holding member, a first magnetic core that is a core half fixed to the holding member at the rear of the side portion thereof, and a gap abutment between the first magnetic core and the second magnetic core. a second magnetic core, which is a core half disposed opposite to the first magnetic core; and then connect the gap abutting surface to the first gap through the gap material.
A magnetic core that is abutted against the gap abutment surface and has a front portion of its side portion protruding from a side portion of the holding member, and a front portion of the side portions of the first magnetic core and the second magnetic core are sandwiched together. An elastic holding member is used to hold the first part through the gap material.
The abutting surfaces of the magnetic core and the second magnetic core are brought into close contact with each other, and the second magnetic core is attached to the holding member via the first magnetic core, and at least one of the first magnetic core and the second magnetic core. The structure is such that an integrated assembly consisting of a coil held on one side is assembled into a shield case.

Further, in order to achieve the above-mentioned object, the method for manufacturing a magnetic head of the present invention includes fixing the rear part of the side portion of the first magnetic core, which is a core half, to a flat holding member, and aligning the gap of the first magnetic core with each other. a step of positioning the first magnetic core and a first core half disposed opposite thereto so that the surface thereof faces upward with respect to the holding member and the front portion of the side portion protrudes from the side portion of the holding member; a step of supporting a coil on at least one of the two magnetic cores, and arranging the second magnetic core to face the first magnetic core on mutually gap abutting surfaces with a gap material interposed therebetween;
The front portions of the side portions of the magnetic cores are held together by elastic holding members, and the gap abutting surfaces of the first magnetic core and the second magnetic core are brought into close contact with each other via the gap material, and the second magnetic core is The first
The method includes the steps of attaching to the holding member via a magnetic core, and incorporating the assembly integrated through the above steps into a shield case.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 4 to 6. In the drawings, the same reference numerals as in FIGS. 1 to 3 indicate the same or equivalent parts.

A synthetic resin is applied or printed in advance to the surface of the first magnetic core 2 to be attached to the hold case 1, and is dried at a low temperature to form a resin film. On the other hand, as shown in the figure, the hold case 1 has a substantially flat plate shape. This hold case 1 is attached to a moving jig, and the first magnetic core 2 is joined to a predetermined location of the hold case 1 using the built-in jig. In this state, while applying pressure to the first magnetic core 2, The first magnetic core 2 is fixed to the hold case 1 by heating to melt the resin film, and then cooling and solidifying the resin film.

Next, the butt portion 2a of the first magnetic core 2 is polished,
A coil bobbin 7 wound with a coil 5 and provided with a terminal 6 is attached to the first magnetic core 2.

On the other hand, the abutting portion 4a of the second magnetic core 4 is polished, and the abutting portion 4a and the abutting portion 2a of the first magnetic core 2 are abutted with the gap plate 8 interposed therebetween. In this state, directly on the sides of the first and second magnetic cores 2 and 4,
A non-magnetic and elastic pressing member 9 having a substantially U-shaped side surface is fitted, and the first and second magnetic cores 2,
4 are fixed to each other, a magnetic head structure A shown in FIG. 5 is obtained.

Then, this magnetic head structure A is assembled into a shield case (not shown) while pressing the side surface of the hold case 1 against the inner wall surface of the shield case, and is fixed in the shield case by injecting adhesive or synthetic resin. Thereafter, the magnetic tape sliding surfaces of the first and second magnetic cores 2 and 4 are polished to complete the magnetic head.

Therefore, in this magnetic head structure A, a flat hold case 1 is used instead of a box-shaped hold case as in the conventional case, and the holding member 9 is directly attached to the first and second magnetic cores 2 and 4. Since the first and second magnetic cores 2 and 4 are butted and fixed by fitting, the width B can be made smaller than the width of the conventional magnetic head, as shown in FIG. can.

The shape of the hold case 1 itself is simple, and only one hold case 1 is required, the number of parts is small, there is no need to use complicated molds, and dimensional accuracy is improved compared to conventional ones. The permissible range expands.

Further, since the holding member 9 is directly fitted to the first and second magnetic cores 2 and 4, and the tightening force of the holding member 9 acts in the direction of the abutting portions 2a and 4a, the abutting portion 2
Since the pressure welding force of a and 4a is strong and the pressure welding is reliable,
It is possible to reduce the adverse effect on the pressure contact force due to expansion and contraction of the fixing synthetic resin or adhesive, and as a result, high gap accuracy can be maintained.

Moreover, in the conventional manufacturing method, the first and second magnetic cores 2 and 4 are assembled in a hold case.
Because the abutting parts 2a and 4a of the
In a magnetic head constructed by incorporating a plurality of magnetic cores into a hold case, it is difficult to maintain the flatness of mutually polished surfaces. In this regard, in the present invention, the second magnetic core 4 is polished as a single core, and then the first core 4 is polished.
Since the flatness of the plurality of magnetic cores can be achieved independently by abutting against each other, the negative effect of uneven flatness as in the conventional case is eliminated, and the gap accuracy is improved from this point as well.

Furthermore, in the present invention, since the hold case 1 is one piece, polishing time and storage space are reduced.
Furthermore, there are many advantages in that the amount of polishing that can be finished with one polishing machine increases compared to conventional polishing machines.

In addition, in the above embodiment, when forming the gap part,
Although the method using the gap plate 8 has been described, a method of providing a thin film on the abutting portions 2a and 4a by sputtering, plating, printing, coating, etc. may also be used. When using this method, by providing a thin film on the second magnetic core 4,
A large amount of gap formation work is performed in one operation.

Furthermore, in the above embodiment, the first magnetic core 2 is fixed to the hold case 1 using a synthetic resin or an adhesive, but it is also possible to use a low-melting metal such as solder. It may be fixed by a method of fixing via an insert member or by a method of forming a locking part such as a groove in the hold case and fixing there.

As shown in FIG. 5, if the presser member 9 is fitted in the vicinity of the gap plate 8 (gap material) of the first magnetic core 2 and the second magnetic core 4, the clamping force of the presser member 9 can be increased. This effectively acts on the abutting portions 2a, 4a of the respective magnetic cores 2, 4, thereby more reliably preventing the operating gap from opening too much due to external force.

〔Effect of the invention〕

As explained above, according to the present invention, since the first magnetic core and the second magnetic core are directly clamped toward the operating gap side by the holding member, the operating gap is moved by an external force. There is no possibility of the gap becoming too wide, and therefore the desired gap accuracy can be reliably maintained. Further, since the structure is such that the first magnetic core and the second magnetic core are held in one holding member, the number of parts can be reduced, and the size and weight can be reduced. Further, since the holding member itself has a simple flat plate shape, there is no need to use a complicated mold, and the allowable range of dimensional accuracy is widened compared to conventional ones. Further, since both the first and second magnetic cores are held between the elastic holding members at the protruding portions from the holding member, the width B of the magnetic head structure A is as shown in FIG. It is also possible to make it smaller. Furthermore, since the holding member, the first magnetic core, the second magnetic core, and the coil are reliably integrated by the fixation of the first magnetic core to the holding member and the tightening force of the pressing member, the assembly The body is easy to handle and productivity can be improved.
Furthermore, when a plurality of magnetic head units are attached to a single holding member, the second magnetic core in each magnetic head unit can be polished individually and then matched against the first magnetic core. The abutting surfaces can each independently achieve flatness with high precision, and the gap of each magnetic head unit can be accurately defined.

[Brief explanation of drawings]

Figure 1 is an exploded perspective view of a conventional magnetic head, Figure 2 is an exploded perspective view of a conventional magnetic head.
The figure is a perspective view of the assembled magnetic head.
4 is an exploded perspective view of a magnetic head according to an embodiment of the present invention, FIG. 5 is a perspective view of the assembled magnetic head, and FIG. 6 is a front view of the magnetic head. FIG. 1... Hold case, 2... First magnetic core,
4... Second magnetic core, 5... Coil, 6... Terminal, 7... Coil bobbin, 9... Holding member.

Claims (1)

[Scope of Claims] 1. One flat plate-shaped holding member, the rear part of the side portion thereof being a first magnetic core that is a core half fixed to the holding member, and the gap abutting surface of the first magnetic core being fixed to the holding member. and a second magnetic core which is a core half disposed opposite to the first magnetic core, with the front part of the side part protruding upward from the side part of the holding member, and the second magnetic core being a core half disposed opposite to the first magnetic core, The gap butting surface is
A magnetic core that is abutted against the gap abutment surface and has a front portion of its side portion protruding from a side portion of the holding member, and a front portion of the side portions of the first magnetic core and the second magnetic core are sandwiched together. An elastic presser member is used to hold the first part through the gap material.
Gap abutting surfaces of the magnetic core and the second magnetic core are brought into close contact with each other, and the second magnetic core is attached to the holding member via the first magnetic core;
1. A magnetic head, characterized in that an integral assembly comprising at least one of the first magnetic core and a coil held in the second magnetic core is assembled in a shield case. 2. The magnetic head according to claim 1, wherein a plurality of magnetic head units are attached to the holding member, and the operating gap of each magnetic head unit is located in the same plane and in a straight line. . 3. Fixing the rear part of the side part of the first magnetic core, which is a core half, to a flat holding member, with the gap abutting surface of the first magnetic core facing upward with respect to the holding member, and the front part of the side part a step of positioning the holding member so as to protrude from a side portion thereof; and supporting a coil on at least one of the first magnetic core and a second magnetic core, which is a core half disposed opposite to the first magnetic core; a step of arranging the first magnetic core and the second magnetic core to face each other on their gap abutting surfaces via a gap material, and sandwiching the front portions of the side portions of the first magnetic core and the second magnetic core with elastic pressing members. a step of bringing the gap abutting surfaces of the first magnetic core and the second magnetic core into close contact with each other via the gap material, and attaching the second magnetic core to the holding member via the first magnetic core; A method for manufacturing a magnetic head, comprising the step of assembling the assembly integrated by the above-described steps into a shield case.