JPH0654526B2 - Method of manufacturing magnetic head - Google Patents

Description

The present invention relates to a method of manufacturing a magnetic head, and more specifically, a ring-shaped magnetic core and a center shim are formed using a strip-shaped composite plate material, and both sides of the center shim are formed. The present invention relates to a method for manufacturing an erasing magnetic head having a structure in which a magnetic gap is formed in the.

[Prior Art] The structure of a core unit including a magnetic core and a bobbin of a conventional erasing magnetic head of this type is as shown in FIG. 5, and is assembled by the following steps.

In FIG. 4, reference numeral 1 is a ring core which is the above-mentioned ring-shaped magnetic core. First, the ring core 1 is formed by bending an elongated rectangular plate made of a metal having high magnetic permeability into a ring shape as shown in the drawing.

However, the interval between the opposed tip portions 1a, 1a forming the magnetic gap of the ring core 1 is set larger than the illustrated interval, and in this state, the bobbin 4 around which the winding wire 6 is wound next is fitted into the ring core 1. Terminals 5 and 5 to which both ends of a winding 6 are connected are planted in the bobbin 4.

Next, a force is applied to the tip portions 1a, 1a of the ring core 1 as indicated by an arrow F to make the distance between the tip portions 1a, 1a predetermined.

Next, a center shim 2 made of a high-permeability material sandwiched by a spacer 3 made of a non-magnetic material is sandwiched between the tip portions 1a, 1a, and then the center shim 2 and the spacer 3 are formed by bonding, brazing, welding or the like. Is fixed between the tip portions 1a, 1a to obtain a core unit indicated by reference numeral 7 in FIG.

Then, after the core unit 7 is fitted into a holder (not shown) and fixed, the tip end surface of the ring core 1 is ground together with the center shim 2 and the spacer 3 into a cylindrical shape as shown by the alternate long and short dash line in FIG. The sliding surface is formed to complete the magnetic head.

[Problems to be Solved by the Invention] However, according to the above-described manufacturing method, the center shim 2 is separate from the ring core 1 and the tip portions 1a, 1 of the ring core 1 are separated.
Since it is sandwiched between a, the center shim 2 is displaced in the width direction (vertical direction in the figure) with respect to the tip portions 1a, 1a of the ring core 1 as shown in FIG. As a result, there is a problem that the dimensional accuracy such as the track width and the track position deteriorates.

[Means for Solving the Problems] In order to solve the above-mentioned problems, in the method of manufacturing a magnetic head according to the present invention, a strip-shaped composite plate material obtained by joining non-magnetic plate materials to both side surfaces of a high magnetic permeability plate material. The composite plate material is formed from one end to the other end into first, second, third and fourth regions, and the first and second regions are bent by bending between the first and second regions. And a step of bending at least a part of the third region,
A step of forming a center shim by adjoining a fourth area and forming a high-permeability plate material portion of the first area; and separating the adjacent first and second areas by separating the second and fourth areas. The step of forming the magnetic gaps on both sides of the center shim by the non-magnetic plate material portions sandwiched by the high-permeability plate materials in the region (1).

[Operation] According to the above-described manufacturing method, the center shim can be configured by bending the tip portion (first region) of the composite plate material and adjoining the second region, so that the first region is the tip portion of the ring core. The second region can be accurately and easily overlapped in the width direction of the composite plate material (the magnetic gap length direction when the magnetic head is formed) without causing positional displacement.

Furthermore, even when the fourth region forming the tip of the ring core together with the second region is adjacent to the first region serving as the center shim, the first region remains fixed to the second region. Therefore, the fourth region is accurately and easily overlapped with the first region in the width direction of the composite plate material (the magnetic gap length direction when the magnetic head is constructed) without causing positional displacement. be able to.

[Embodiment] Hereinafter, details of an embodiment of the present invention will be described with reference to Figs. In addition, in FIG. 1 to FIG.
The same or corresponding parts as those in FIGS. 6 to 6 are designated by the same reference numerals.

1 and 2 are views for explaining a method of manufacturing a core unit of an erasing magnetic head according to the present embodiment, and are perspective views of a shim forming portion to be described later before and after being fixed.

In FIG. 1, a ring core 1 is formed by bending a long and thin rectangular composite plate material in which nonmagnetic plate materials 9 are joined to both side surfaces of a high magnetic permeability plate material 8 into a ring shape. A shim forming portion 10 for forming a center shim is continuously formed at one end 1a of the ring core 1, that is, integrally formed with the ring core 1. Further, on the outer surface of the base end portion of the shim forming portion 10, a groove 11 is formed with a predetermined depth over the entire width of the shim forming portion 10 so that the shim forming portion 10 can be bent later.

In the assembling process with the structure of the ring core 1 as described above, first, as in the case of the conventional example, the interval between the tip portions 1a, 1a is set large, and the bobbin 4 around which the winding wire 6 is wound is fitted into the ring core 1. The bobbin 4 has the same structure as the conventional one, and terminals 5 and 5 to which both ends of the winding 6 are connected are implanted.

Next, the shim forming portion 10 is bent in a U-shape at the groove 11 and folded back inside the tip portion 1a so as to be overlapped. Further, a force is applied from both sides to the tip portions 1a, 1a of the ring core to bring them closer to each other. As shown in the figure, the shim forming portion 10 is attached to the tip portion 1a,
The core units 7 shown in the same figure are obtained by fixing them by lapping, bonding, brazing, welding or the like between the 1a.

Next, as in the case of the conventional example, the core unit 7 is fitted into a holder (not shown) and fixed, and then the tip end surface of the ring core 1 is formed into a cylindrical shape together with the shim forming portion 10 as shown by a dashed line in FIG. Grinding is performed, the bent portion is removed from the shim forming portion 10, the sliding surface of the magnetic recording medium is formed, and the magnetic head is completed.

A center shim is formed by the high-permeability plate material 8 portion of the shim forming portion 10, and the non-magnetic plate material 9 portion of the shim forming portion 10 and the non-magnetic plate material 9 portion inside each of the tip portions 1a, 1a on both sides in contact with this portion Form the magnetic gaps on both sides of the center shim.

According to the method as described above, since the shim forming portion 10 is continuous with the one tip portion 1a of the ring core, the tip portion 1
There is no positional deviation in the width direction with respect to the continuous tip portion 1a when it is sandwiched between a and 1a. Also, the shim forming portion 10
It is extremely easy to accurately superimpose the tip portion 1a which is not continuous.

Therefore, as shown in FIG. 3 in which the shim forming portion 10 is sandwiched and fixed, the shim forming portion 10 is not displaced in the width direction with respect to the tip portions 1a, 1a of the ring core 1.
Therefore, there is no deviation in track width or track position deviation,
The track width and the like determine the track position with high accuracy, and the characteristics of the magnetic head are improved.

Further, according to the present embodiment, since the shim forming portion 10 is integrated with the ring core 1, the number of parts can be reduced and the manufacturing cost can be reduced as compared with the conventional separate body.

Even if the shim forming portion 10 is separated from the ring core 1 and sandwiched between the tip portions 1a, 1a and fixed regardless of the above method, the number of parts can be reduced by the non-magnetic spacer as compared with the conventional case. it can. In addition, since it is inserted and fixed by itself without a spacer, the work becomes easier, and even if it is not easier than the above-mentioned embodiment, the track width and the track position can be more easily obtained with higher accuracy than before. You can

In the above structure, the ring core 1 is integrated as a whole, but a pair of core halves or more core constituent members may be connected in a ring shape.

[Effect] As is clear from the above description, in the method of manufacturing a magnetic head according to the present invention, a strip-shaped composite plate material obtained by joining nonmagnetic plate materials to both side surfaces of a high magnetic permeability plate material is used. Forming a first, second, third, and fourth region from one end to the other end, and bending between the first and second regions to make the first and second regions adjacent to each other, At least a part of the third region is bent to adjoin the first and fourth regions,
A step of forming a center shim with the high magnetic permeability plate material portion of the first region, and a step of separating the adjacent first and second regions with the high magnetic permeability plate material of the second and fourth regions. The step of forming the magnetic gaps on both sides of the center shim with the sandwiched non-magnetic plate material portion is adopted, so that the accuracy of the track width and the track position of the manufactured magnetic head can be improved to improve the erasing performance. Moreover, the excellent effect that the number of parts can be reduced and the cost can be reduced can be obtained.

[Brief description of drawings]

1 and 2 illustrate the structure of a magnetic head according to an embodiment of the present invention together with the assembling process. FIG. 1 is a perspective view of the core unit before fixing the shim forming portion, and FIG. 2 is the shim forming portion. FIG. 3 is a perspective view of the core unit after fixing, FIG. 3 is an explanatory view of a fixed state of the shim forming portion of FIG. 2, FIG. 4 is a perspective view of the core unit of the conventional head before fixing the center shim, and FIG. FIG. 6 is a perspective view of the core unit after the center shim of the head is fixed, and FIG. 6 is an explanatory diagram of a position shift state of the center shim in FIG. 1 ... Ring core, 4 ... Bobbin 5 ... Terminal, 6 ... Winding 8 ... High permeability plate material, 9 ... Non-magnetic plate material 10 ... Shim forming part, 11 ... Groove

Claims (1)

[Claims] 1. A strip-shaped composite plate material obtained by joining non-magnetic plate materials to both side surfaces of a high-permeability plate material, and the composite plate material is provided from one end to the other end in first, second, third and fourth regions. And a step of bending between the first and second regions to make the first and second regions adjacent to each other; and bending at least a part of the third region to form the first and second regions.
A step of forming a center shim by adjoining a fourth area and forming a high-permeability plate material portion of the first area; and separating the adjacent first and second areas by separating the second and fourth areas. A step of forming a magnetic gap on both sides of the center shim with a non-magnetic plate material portion sandwiched by high-permeability plate materials in the region of.