JPS6333203B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention includes a recess forming step of forming a recess on the front surface of a case, a contacting step of bringing a wear-resistant material into contact with the recess, and a step of bringing the wear-resistant material into contact with the recess of the case. The present invention relates to a method for manufacturing a magnetic head case, which includes a welding step of welding a magnetic head case.

Since a magnetic head records and reproduces information by sliding against a recording medium, its sliding surface is worn out as the head slides. When a magnetic tape is used as the recording medium and the magnetic tape can be used back and forth (in the case of two tracks), the core portion (the portion for recording and reproducing) is formed with a track width approximately half the tape width. I'm letting you do it. In this case, if the tape sliding surface of the core and the remaining tape sliding surface are made of materials with different hardness (wear resistance), the sliding of the head may be caused by long-term sliding with the magnetic tape. The flatness of the moving surface is lost, the contact between the core of the magnetic head and the magnetic tape deteriorates, and the frequency characteristics during recording and reproduction deteriorate. For this reason, it is desirable to use a material having substantially the same wear resistance as the core for the remaining tape sliding surface. Since information is not recorded or reproduced on the remaining tape sliding surface, the tape sliding surface can be formed on the front surface of the magnetic head case. On the other hand, in recent years, hard permalloy,
The wear resistance of the core is increased by using a highly hard material such as sendust. Therefore, it is advantageous to form the case from the same material as the core. but,
There are no particular problems with hard permalloy, sendust, etc. when they are made into a plate shape like a core, but it is difficult to draw them into a case (decreased press processing accuracy, shortened press die life, workpiece (occurrence of cracks, etc. in the material). Therefore, as shown in Figure 1 (perspective view of the head case), a material with high magnetic permeability that is easy to draw,
For example, the case 1 is made of permalloy or the like. The case 1 is provided with an opening 1a for exposing the core (not shown) and an opening 1b for fitting the sliding plate 2 (however, in the figure, the openings 1a and 1b are one continuous exhibiting an aperture). A sliding plate 2 made of a high magnetic permeability material having the same hardness as the core can be welded to the case 1 fitted into the opening 1b. However, since the sliding plate 2 requires a shielding (magnetic shielding) effect, it must be made of a material with high magnetic permeability as described above, and the dimensions of the sliding plate 2 must be adjusted with precision in order to fit into the opening 1b. High processing is required, and furthermore,
The process of welding the sliding plate 2 to the case 1 was complicated. Therefore, the manufacturing cost of the head case is high.

The method of manufacturing a magnetic head case according to the present invention eliminates the above-mentioned drawbacks, and the present invention will be explained below with reference to the drawings.

FIG. 2 is a perspective view showing the case 3 and the sliding plate 4 in order to explain the abutment step in the manufacturing method of the present invention. In FIG. 2, the case 3 is made of a high magnetic permeability material such as permalloy that is easy to draw, and has an opening 3a for exposing the core (not shown).
A recess 3b for attaching the sliding plate 4 is provided on the front surface of the case 3 (on the side on which a tape (not shown) slides). The depth d of the recess 3b is formed by press working or the like so that it is approximately equal to the thickness t of the sliding plate 4 (recess forming step), and a protruding protrusion 3c is further formed in the recess 3b. let The sliding plate 4 is the opening 3
An unillustrated core exposed from a (7a in FIG. 4,
As shown in 7b, a material with wear resistance equivalent to (using hard permalloy, sendust, etc.) (the above-mentioned hard permalloy, sendust, etc. may be used, but stainless steel can also be added)
to form.

Here, it does not matter whether the sliding plate 4 is made of a high magnetic permeability material or not. Further, the dimensions of the sliding plate 4 may be any shape as long as it can come into contact with the recess 3b, so high precision is not necessarily required.

FIG. 3 shows the concave portion 3b of the case 3 in FIG.
It is a cross-sectional view of the main part when the sliding plate 4 is brought into contact with the slide plate 4, cut along the dashed line A, and viewed in the direction of the arrow B, and is a diagram for explaining the welding process.
In FIG. 3, an electrode 5a is brought into contact with a portion of the case 3, and an electrode 5b is brought into contact with a portion of the sliding plate 4. Electric power from a power source 6 is supplied to the electrodes 5a and 5b. Then, when the case 3 and the sliding plate 4 are sandwiched between the electrodes 5a and 5b, the current density near the convex part 3c provided in the concave part of the case 3 increases and generates Joule heat. The generated heat melts the material near the convex portion 3c, so that the case 3 and the sliding plate 4
can be spot welded. Therefore, since a part of the case 3, that is, a high magnetic permeability material exists at the bottom of the sliding plate 4, it has a shielding (magnetic shielding) effect, and as described above, the sliding plate 4 is made of a high magnetic permeability material. There's no need to. The sliding plate 4 has an opening 3a (second
A material having the same hardness (wear resistance) as the cores 7a and 7b (see FIG. 4) exposed from the cores 7a and 7b (see FIG. 4) can be selected from among many materials. Also,
Since the sliding plate 4 is spot welded to the recess 3b of the case 3, the manufacturing process is simplified and the manufacturing cost of the head case can be reduced. The method for manufacturing the magnetic head case of the present invention can be comprised of the recess forming step, the abutting step, and the welding step as described above.

FIG. 4 is a perspective view of a magnetic head manufactured using the head case of FIG. 3. The magnetic head shown in FIG. 4 is constructed by inserting a head body (not shown) into a case 3 to which a sliding plate 4 is welded as shown in FIG.
b) is exposed through an opening 3a (see FIG. 2) formed on the front surface of the case 3. and,
The head body is held in the case 3 by a core holder 8. The magnetic head shown in Figure 4 has core 7.
Since the parts a and 7b and the sliding plate 4 have the same level of wear resistance, even if the magnetic tape (not shown) slides for a long time, the tape sliding surface will wear evenly and maintain good flatness for a long time. Can keep time.

As described above, the method for manufacturing a magnetic head case of the present invention can reduce the manufacturing cost of a head case in which a tape sliding surface is formed which wears out substantially equally as the core.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the magnetic head case, FIG. 2 is a perspective view of the magnetic head case showing the abutting process in the manufacturing method of the present invention, and FIG. 3 is a perspective view of the magnetic head case showing the welding process in the manufacturing method of the present invention. 4 is a perspective view of a magnetic head formed by incorporating a head element into a head case manufactured by the method of manufacturing a magnetic head case of the present invention. In the figures, 3...case, 3a...opening Part, 3b...Concave part, 3c...Convex part, 4...Sliding plate, 5a, 5b...Electrode, 6...Power source, 7a, 7
b... Core, 8... Core holder.

Claims (1)

[Claims] 1. A recess forming step for providing a recess on the front surface of a case made of a high magnetic permeability material and enclosing the head element, and a material having wear resistance is brought into contact with the recess formed in the recess forming step. a welding step of welding the high magnetic permeability material of the recessed part and the wear-resistant material that have come into contact with each other in the abutting step, and a welding step of welding the wear-resistant material to the recessed part of the front surface of the case in the abutting step. A method for manufacturing a magnetic head case, characterized in that a step of forming a convex portion for almost point contact with a substance is provided before the contact step, and the convex portion is spot welded in the welding step. . 2. The magnetic head case according to claim 1, wherein the step of forming the convex portion is a step of forming a convex portion smaller than the concave portion approximately in the center of the concave portion formed in the concave portion forming step. manufacturing method.