JPH079688B2 - Method of manufacturing magnetic head - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head, and more particularly to a method for manufacturing a voice recording / playback head used in audio and video equipment.

(Prior Art) The structure of a conventional magnetic head for audio used in audio / video equipment will be described.

FIG. 6 is a cross-sectional view of a magnetic head manufactured by a conventional manufacturing method. In FIG. 6, 1 and 8 are magnetic core halves having laminated permalloy plates, and both magnetic core halves 1 and 8 are gaps. Magnetic core having a magnetic gap 10 butted through the material
Forming 11 2 is a magnetic core pressing member made of beryllium copper, 3 is a hold case for fixing two magnetic cores 11 in parallel, 4 is a coil bobbin, 5 is a coil lead terminal, 6 is a shield case, and 7 is a bobbin. A wound coil, 9 is injected resin.

FIG. 7 is a perspective view for explaining the assembling method of the conventional magnetic head shown in FIG. 6, and the manufacturing method will be described below with reference to FIGS.

Rear core 1 of magnetic core halves 1 and 8 made by stacking Permalloy
Insert a and 8a into the coil bobbin 4 around which the coil 7 is wound from the left and right, and insert the tip core portions 1b and 8b, and each other through the gap material,
After abutting, the magnetic core 11 is formed by fixing the back portions 1c and 8c of both magnetic core halves with the holding member 2.
It is necessary to correct the abutting dimension position of the tip core portions 1b and 8b using a microscope. Next, after fixing the magnetic core 11 at a predetermined position of the hold case 3, the hold case is inserted into the shield case 6, and then the magnetic core 11 is inserted.
Then, the inside of the shield case 6 is completely fixed by injecting and hardening the resin 9 into the gap between the shield case 3 and the case. Next, the surface contacting the magnetic medium is tip-polished so that the tips of the shield case 6 and the magnetic core 11 are flush with each other to obtain a magnetic head.

(Problems to be Solved by the Invention) As described above, in the conventional method of manufacturing a magnetic head, the rear cores 1a and 8a of the magnetic core halves 1 and 8 are inserted into the mounting holes of the coil bobbin 4, and the tip core is inserted. Since the magnetic cores 11 are formed by abutting the parts 1b and 8b and fixing them with the pressing member 2, the abutting of the tip cores 1b and 8b can be accurately performed using a microscope, but it is difficult to carry them during the manufacturing process. Alternatively, when the hold case 3 is inserted into the shield case 6, there is a problem that the butted portion is displaced.

In the latter case, since the tip cores 1b and 8b of the magnetic cores 1 and 8 are flush with the surface of the shield case 6 or are inside the shield case 6, the positions of the tip cores 1b and 8b are It was difficult to correct the gap.

(Means for Solving the Problems) The present invention has been made to solve the above problems, and includes a winding coil used for recording and reproduction on a magnetic recording medium, and a pair of left and right magnetic core halves. In the method of manufacturing a magnetic head, a protrusion for fixing the left and right magnetic cores is provided at the tip of the pair of left and right magnetic core halves contacting the magnetic recording medium, and the protrusion when the pair of magnetic core halves is butted The step of fixing by inserting an elastic pressing member into the recess formed in the portion to form a magnetic core, the magnetic core is inserted into a shield case, and the protrusion protruding from the tip of the shield case is used. A step of improving the abutting accuracy of the magnetic core; a step of injecting a resin into the shield case to fix the inside of the shield case; a protruding portion protruding from the shield case; The present invention aims to provide a method for manufacturing a magnetic head, which is characterized by comprising a step of cutting and polishing.

(Embodiment) FIG. 1 is an assembly sectional view for explaining a method of manufacturing a magnetic head according to the present invention, FIG. 2 is a perspective view for explaining an method of assembling the magnetic head shown in FIG. 1, and FIG. FIG. 4 is a plan view showing a magnetic core of an essential part of the present invention shown in FIGS. 1 and 2, wherein the same components as those of the conventional magnetic head are designated by the same reference numerals, and the description thereof will be omitted. Focus on the differences.

The magnetic head manufacturing method according to the present invention is different from the conventional example in that it is used in the present invention as shown in FIG.
The pair of magnetic core halves 20 and 21 has a large tip core portion, and further uses a U-shaped cutout portion 20b, 21b formed on the back portion of the abutting surface 20a, 21a of the tip core portion. When a common coil bobbin 4 in which a coil 7 is wound around the magnetic core halves 20 and 21 is incorporated and the magnetic core halves 20 and 21 are butted against each other to form a magnetic core 23, a U-shaped cutout 20b, It is fixed to 21b by using a pressing member 22 having a claw portion 22a as shown in FIG.

That is, the magnetic core halves 20 and 21 are made of thin permalloy plates.
Since the punched out shape shown in the figure is formed by stacking, the U-shaped cutouts 20b, 21b can be accurately obtained in the shape dimension, and the claw portion 22a fitted to this can be cut out. By fitting it in, the tip core can be fitted almost exactly.

Therefore, after attaching the above two magnetic heads to the hold case 3 and inserting them into the shield case 6, the magnetic cores 20, 21
The dimensional position of was accurately adjusted while protruding from the window of the shield case 6. The resin 9 is injected into the gap between the rear shield case 6 and the magnetic core 23 and cured to completely fix the inside of the shield case. Next, the protruding portion of the tip core portion is cut and polished so that the shield case 6 and the tips of the magnetic cores 20 and 21 are flush with each other to obtain a magnetic head having excellent precision and characteristics.

FIG. 5 is a perspective view of the magnetic head that has been polished.

(Effect) As described above, according to the method of manufacturing a magnetic head of the present invention, the magnetic core tip portion is pressed by the pressing member, so that the magnetic core is little displaced during the manufacturing process, and the magnetic core is incorporated in the shield case. Even if the position shifts later, since the magnetic core projects from the window of the shield case, it is possible to easily correct the position shift from the outside, improving yield and improving workability and reducing man-hours. I can.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a magnetic head according to the present invention before cutting a magnetic head protrusion, FIG. 2 is a perspective view illustrating a method of assembling a magnetic head of the present invention, and FIG. 3 is a magnetic core of the present invention. FIG. 4 is a plan view, FIG. 4 is a holding member of the present invention, FIG. 5 is a perspective view of a completed magnetic head, FIG. 6 is a sectional view of a magnetic head manufactured by a conventional manufacturing method, and FIG. FIG. 6 is a perspective view illustrating a method of assembling the head. 20,21 ...... Magnetic core half body, 22 ...... Presser member, 3 ...... Hold case, 4 ...... Bobbin, 5 ...... Lead terminal, 6 ......
Shield case, 7 ... Coil, 9 ... Resin,

Claims (1)

[Claims] 1. A method of manufacturing a magnetic head comprising a winding coil used for recording and reproduction on a magnetic recording medium and a pair of left and right magnetic core halves, wherein a pair of left and right magnetic core halves contacting the magnetic recording medium are provided. Protrusions for fixing the left and right magnetic cores are provided at the tip portion, and when the pair of magnetic core halves are butted, the elastic presser member is fitted into the recess formed in the protrusions to fix the magnetic core halves. A step of forming a magnetic core, a step of inserting the magnetic core into a shield case and increasing the accuracy of abutment of the magnetic core with the protrusion protruding from the tip of the shield case, and injecting a resin into the shield case. A method of manufacturing a magnetic head, comprising: a step of fixing the inside of the shield case; and a step of polishing or cutting and polishing a protrusion protruding from the shield case.