JP2976470B2 - Manufacturing method of core for magnetic head - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to a method for manufacturing a magnetic head core, and more particularly to a magnetic head having improved productivity of a multi-track magnetic head using a laminated core. The present invention relates to a method for manufacturing a core.

2. Description of the Related Art A conventional multi-track magnetic head using a laminated core will be described with reference to FIGS. FIG. 4 shows a 4-track head (1) for an audio cassette. Laminated cores (3), (4), (5) and (6) for four tracks are laminated in a shield case (2), and an epoxy resin (7) is used. ) Is filled and fixed.
The magnetic tape contact surfaces (8), (9), (10), and (11) of the laminated cores (3), (4), (5), and (6) have windows of the shield case (2) with a specified vertical interval. Exposed from the part (12) and the magnetic tape contact surface (1) of the shield case (2).
After grinding to the same surface as 3), mirror finish is applied by lapping.

The laminated cores (3), (4), (5) and (6) are made of a predetermined number of cores (14) (14)... Formed by a thin plate of a magnetic material such as permalloy shown in FIG. It is formed by lamination. The cores (14) (14) are usually laminated by bonding with an epoxy resin or the like.
(14) ... dowels (not shown) for positioning are provided by press working, the dowels are aligned and laminated, and the laminated cores (3) (4) (5) (6) are used without using an adhesive. Methods of forming have also been proposed.

On the other hand, as shown in FIG.
(4) At the rear of (5) and (6), coils (15) (15) (1
5) Due to the winding of (15), the laminated cores (3), (4), (5) and (6) provided inside the shield case (2) are fixed in an inclined manner. Therefore, the magnetic tape contact surface (8) of the laminated cores (3) (4) (5) (6) before the grinding operation
As shown in FIG. 6, (9), (10) and (11) project obliquely with respect to the magnetic tape contact surface (13) of the shield case (2), so that a great deal of grinding and lapping processing is required. Time and effort are required. In order to improve the productivity, the magnetic tape contact surfaces (8), (9), (10), and (11) of the laminated cores (3), (4), (5), and (6) are indicated by dotted lines in FIG. As shown in the figure, it is necessary to form the stairs and minimize the amount of grinding as much as possible.
(14) are sequentially shifted to produce a laminated core having the above-mentioned shape using an adhesive and a dedicated fixing jig.

In addition, (16), (16), and (16) are channel shield plates, and (17), (17),... Are connection terminals.

[Problems to be Solved by the Invention] When manufacturing the laminated core into the shape shown by the dotted line in FIG. 6 using the above-mentioned conventional cores (14), (14). It is applied to the cores (14), (14) ... and set in a special jig, and the front magnetic tape contact surface is sequentially displaced and pressure-bonded, so the number of steps is large and there is a problem in mass productivity. .

Therefore, there arises a technical problem to be solved in order to simplify the manufacturing process, improve mass productivity and reduce the manufacturing cost, and an object of the present invention is to solve the problem.

Means for Solving the Problems The present invention has been proposed in order to achieve the above object, and has a dowel for positioning and the like on a surface of a plurality of cores constituting a laminated core of a magnetic head. A magnetic tape contact surface of the plurality of cores in the core of the magnetic head forming the laminated core by combining the laminated cores by the engaging means. The front surface of the laminated core formed by sequentially laminating the cores is formed so as to have a step shape having a predetermined inclination angle, and the magnetic tape of the front surface of the laminated core and the shield case attached to the shield case at a predetermined angle. A four-core head core is characterized in that the contact surface is substantially parallel and the front surface of the laminated core is ground to form a smooth magnetic tape contact surface. It does not provide a manufacturing method.

[Operation] According to the present invention, when the respective cores are matched in a predetermined stacking order by engaging means such as dowels provided on each of the cores constituting the laminated core, the respective cores are relatively positioned. . Each core is cut in advance so that the front surface forms a predetermined inclination angle during lamination, so that when mounted on the shield case, the front surface of the laminate core and the magnetic tape contact surface of the shield case are substantially parallel. Becomes Therefore, the grinding amount when grinding and lapping the front surface of the laminate core and finishing the same surface as the magnetic tape contact surface of the shield case becomes as small as possible.

Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 3 in the accompanying drawings. For convenience of explanation, technical matters belonging to the related art will be described at the same time.

In FIG. 1, reference numeral (20) denotes a permalloy thin plate, which is sequentially transferred to a press machine (not shown) and cores (21) and (22).
Form (23). The figure shows an example in which a laminated core for one track is composed of three cores (21), (22) and (23). First, dowels (24) (24) for positioning are placed on a thin plate (20).
Is pressed, and the first core (21) is provided with engagement holes (25) (2) at the positions of the dowels (24) (24).
5) Drill (25).

Next, the second and third cores (23) and (23)
Holes (27) and (28) notching the front edges (26) (26)... Of the core punching position indicated by the dashed line are formed. Here, the punching amount of the front edges (26) and (26) is 3 times larger than that of the second core (22).
The first core (23) is large, and the positions of the magnetic tape contact surfaces (29) (30) (31) formed by punching are the first to third cores (21) (22). ) In step (23), it is formed so as to retreat sequentially at equal intervals.

Next, as shown on the right side in the figure, punching is performed by press working to form three types of cores (21), (22) and (23) shown in FIG. The engagement holes (25) (25) (25) of these three types of cores (21) (22) (23), and the dowels (24) (24) (24)
When the layers are laminated in conformity with each other, as shown in FIG. 3, a laminate core (32) having a front surface formed in a step shape with a predetermined inclination angle
Is completed, and as described with reference to FIG. 6 of the conventional example, when the laminate core (32) is inserted into the shield case (2).
And the magnetic tape contact surface of the shield case (2) (1
3) becomes substantially parallel, and the amount of grinding required for finishing is reduced.

The angle of inclination of the laminated core (32) can be freely set according to the specifications by the positions and areas of the holes (27) and (28) shown in FIG. 1, and the angle of the multi-layer other than the magnetic head for audio cassette can be set. It can also be applied to track heads.

The present invention can be variously modified without departing from the spirit of the present invention, and it is natural that the present invention extends to the modified one.

[Effects of the Invention] As described in detail in the above embodiment, the present invention can minimize the amount of front protrusion of the laminated core incorporated in the shield case, and the subsequent magnetic tape contact surface In addition to shortening the time required for grinding and lapping processing, the formation of the laminate core does not require a special jig, an adhesive, and an adhesive work, thereby reducing the number of steps and work time, and significantly improving mass productivity. This can contribute to a reduction in manufacturing cost.

[Brief description of the drawings]

1 to 3 show an embodiment of the present invention, FIG. 1 is an explanatory view showing a manufacturing procedure of a core, FIG. 2 is a plan view of the core,
3 is a side view of the laminated core, FIGS. 4 to 6 show a conventional example, FIG. 4 is a side sectional view of a four track head for audio cassette, FIG. 5 is a plan view of the core, FIG. FIG. 6 is a partially cutaway side view of the four track head before the grinding operation. (1) Four track head (21) (22) (23) Core, (24) Dowel (25) Engagement hole (29) (30) (31) Magnetic tape contact surface (32) ... Laminated core

Claims (1)

(57) [Claims] An engaging means such as a dowel for positioning is provided on the surfaces of a plurality of cores constituting a laminated core of a magnetic head, and the laminated cores are connected by the engaging means. In the core of the magnetic head forming the laminated core, the protrusion amounts of the magnetic tape contact surfaces of the plurality of cores are different from each other, and the front surface of the laminated core in which the cores are sequentially laminated has a predetermined inclination angle. It is formed so that the front surface of the laminate core attached to the shield case at a predetermined angle and the magnetic tape contact surface of the shield case are substantially parallel, and the front surface of the laminate core is ground to be smooth. A method for manufacturing a core of a magnetic head, wherein a magnetic tape contact surface is formed.