JPS63133307A - Manufacture of magnetic head - Google Patents

Abstract

PURPOSE:To prevent the generation of fragment on the end face of a core, and also, to simplify the process by inserting a split bobbin into a loop-shaped solid core in which a narrow gap has been formed, and also, injecting simultaneously a shape molding resin into the gap part. CONSTITUTION:A narrow gap (about 50-70mu) is worked and formed in a ferrite corer in which a side core, a center core, a front core and a back core have been formed as one body. A split bobbin 2 is inserted into this back core part and a coil 1 is wound round. Subsequently, at the time of forming a head core, a shape molding resin is injected simultaneously into a gap part 3a, and a magnetic head is formed. Accordingly, a fragment of the end face part of the core is not generated, and also, the process is simplified and the cost can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic head, and more particularly to a method for manufacturing a single-gap type magnetic erase head useful for full-width erase heads for VTRs and the like.

As something similar to this type of magnetic erasing head, a single gap type magnetic erasing head will be described with reference to FIG. This magnetic head consists of a back core 23 and a front core 4, each having a U-shaped cross section, on which a bobbin 2 on which a coil 1 is wound is attached.

The front core 4 is formed by forming a magnetic gap between two core pieces 41 fixed to two mutually parallel end surfaces of the back core 3 by glass bonding. That is, the two core pieces 41 are opposed to each other with the thin lath material 5 interposed therebetween.

However, this magnetic head has a problem in the manufacturing process of the front core 4. That is, after the front core 4 is fixed to the back core 3, the head surface is curved to have a predetermined curvature. However, the magnetic gap portion of the front core 4 has an unstable mechanical strength and has the disadvantage that cracks occur particularly at the c and c' portions at both ends when machining a curved surface.

In view of these points, the present invention creates a narrow gap in a core that integrates a front core and a back core, inserts a bobbin into the part corresponding to the bank core, winds a coil, and injects resin into the gap part after inserting the case. The main purpose of the present invention is to propose a method of manufacturing a magnetic head that eliminates the drawbacks of the conventional method by injecting O (oil) and polishing the head to a predetermined R curvature.

An embodiment of the present invention will be described in detail below with reference to the drawings.

First, as shown in Fig. 1, a narrow gap (approximately 50 to 70μ) 3a is machined in an integrated ferrite core, a split bobbin 2 is inserted as shown in Fig. 2, and as shown in Fig. 3,
Manufacture by winding the fill 1.

As shown in FIG. 4, instead of the conventional positive injection, epoxy resin or the like is also injected into the gap part 3a during head core molding, and the gap part 3a is further polished to a predetermined curvature surface (as shown by the two-dot chain line). and complete it.

As described above, according to the present invention, a narrow gap is formed in a core in which the side core, center core, front core, and back core are set to -4, a split bobbin is inserted into the back core portion, and a fill is wound around the split bobbin. Since the shape molding resin is injected into the above-mentioned gap and molded, there is no chipping of the end face of the core like in the past.
Since the process is simplified, cost F can be reduced. Therefore, it is possible to provide a magnetic erasing head with a low incidence of defective products and stable magnetic characteristics.

[Brief explanation of the drawing]

1, 2, 3, and 4 are process diagrams showing one embodiment of the present invention, and FIG. 5 is a perspective view showing an example of a conventional magnetic head. 1... Coil, 2... Split bobbin, 3... Ferrite core, 3a... Gear knob. Applicant's representative Patent attorney Takashi Akiyama Figure 4 Figure 1 Figure 2 Figure 3118X Figure 5

Claims (1)

[Claims] A narrow gap is molded into the core that integrates the side core, center core, front core, and back core, a split bobbin is inserted into the back core part, a coil is wound around the split bobbin, and a shape molding resin is applied to the gap part. A method for manufacturing a magnetic head, characterized in that the same resin is poured and molded during injection.