JPS6034009A - Ferrite bead inductor element and manufacture of the same - Google Patents

Abstract

PURPOSE:To simplify the manufacturing process by a method wherein a ferrite bead is directly molded on a conductor and formed firmly to make a ferrite bead inductor element. CONSTITUTION:Ferrite powder with a binder of thermosetting or thermoplastic resin is used while the resin is in semi-cured condition. A center part along the longitudinal direction of a conductor is previously set in a molding die. The above ferrite powder is supplied into the die and subjected to a compression molding to adhere tightly on the conductor and maintain the shape. After the molded part is taken out of the die, it is cured in a heating furnace completely. With this constitution, the ferrite powder is fixed to the conductor 2 while its molded shape 5 is maintained with a sufficient strength by the binder resin. Also a bump 7 may be formed near the center part of the conductor to fix the ferrite bead 5 more firmly. A radial lead type inductor element may be formed by molding and curing the bea 5 provided to the top of the conductor 8 bent into an inverted U-shape.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a ferrite bead inductor element and a method for manufacturing the same.

Through-type inductor elements using ferrite cores can be created by selecting the core appropriately.

It is effective in attenuating noise signals of IMHz or higher,
Widely used in various electronic devices.

Conventionally, a typical inductor element of this type has a cylindrical ferrite core (bead) 1 as shown in FIGS. 1 and 2.
Insert the conductive wire 2 into the core, and then inject and harden the adhesive 3 between the conductive wire and the core as well as on both end surfaces of the core, as shown in FIG. 1(b).

Alternatively, as shown in FIG. 2, a structure has been used in which the conductive wires 2 near both ends of the ferrite core 1 are crushed to form 4 to prevent the core 1 from coming off.

However, in conventional structures like this, it is first necessary to pass the conductor through the pores of the core, which can lead to the conductor being bent during the process, and the core may crack or chip in the product. . Furthermore, in the structure shown in FIG. 1, the injection amount is non-uniform due to the small amount of adhesive being injected, and the curing process takes a long time.

During this time, the core and conductor cannot be moved, which makes automation difficult. Also, in the structure shown in Figure 2, the conductor is crushed, so it is easy to break, and the core is not completely fixed to the conductor.
There are various problems such as easy cracking and chipping due to vibration.

SUMMARY OF THE INVENTION In order to eliminate the above-mentioned drawbacks and improve quality and productivity, it is an object of the present invention to provide a ferrite beat inductor element characterized by integrally molding a ferrite core with a conductive wire, and a method for manufacturing the same. .

The present invention will be described in detail below with reference to the drawings.

FIG. 3 shows one embodiment of a ferrite bead inductor element according to the present invention. Further, FIGS. 4 and 5 show other embodiments of the present invention.

In Fig. 6, for example, ferrite powder using a thermosetting or thermoplastic resin as a binder is prepared by using the resin in a semi-cured state and molding the powder into a mold in which the longitudinal center portion of the conductive wire is set in advance. By supplying it to the wire and pressurizing it, it adheres closely to the conductor and maintains its shape. Thereafter, the ferrite powder is removed from the mold and completely cured in a heating furnace, whereby the ferrite powder is fixed to the conductive wire 2 while maintaining its molded shape 5 with sufficient strength by the resin as a binder phase.

In addition, FIG. 4 shows that the ferrite bead 5 after molding and hardening is formed by providing a convex portion 7 as an irregularly shaped portion near the center of the conductor.
This ensures that the wires are more firmly fixed and cannot be pulled out.

Further, in FIG. 5, a ferrite bead 5 is molded and hardened on the top of a conductive wire 8 bent into an inverted U shape to form a radial lead type inductor.

As described above, according to the present invention, the ferrite bead can be molded directly onto the conductor and formed strongly, which simplifies the manufacturing process, facilitates product automation, and makes it less expensive and less likely to crack or chip. It is possible to obtain a good quality inductor element.

[Brief explanation of the drawing]

Fig. 1(,) is a perspective view of a conventional bead inductor element, Fig. 1(b) is a sectional view of Fig. 1(a), and Fig. 2 is a sectional view of another example of the conventional inductor element. 6 and 6 show an integrally molded inductor element according to the invention, and FIGS. 4 and 5 show modified examples of the inductor element according to the invention. In fig.

Claims (1)

[Claims] 1. Ferrite powder containing thermosetting or thermoplastic resin as a binder near the center in the length direction of the conductor. A method for manufacturing a ferrite bead inductor element, characterized in that the conducting wire is passed through and placed in a mold so as to be at the center, and then formed into an annular shape, and then the bonding material is cured and formed. 2. A ferrite bead inductor element made by molding and hardening ferrite powder with a thermosetting or thermoplastic resin as a binder phase into an annular shape near the center of a conducting wire. The ferrite bead according to claim 2, which is formed by bending the central part of the conductive wire into an inverted U shape.
#Work 4, Claim 2 in which the central part of the conductor has an irregular shape
The ferrite bead inductor element described in .