JPH04215412A - Inductor and molded inductor - Google Patents

Abstract

PURPOSE:To automate completely and reduce the cost by making board materials out of conductive material continuously by a progressive metal mold, and by coating them with ferrite resin. CONSTITUTION:Board materials made out of conductive material are formed into a specified shape by punching. For example, inductors 1 are manufactured by punching a long-size board material 2, so called a hoop material, made of low-electric-resistance phosphor bronze, etc., into a specified shape continuously by a progressive metal mold with a specified feed pitch P using the feed holes 3 as datums. Besides, the conductors of molded inductors 5 excluding 4a, 4b to be the terminals of the inductors L are coated with ferrite resin 6. By doing this way, automated collective mass production can be realized, and the manufacturing cost can be reduced. Besides, the inductance becomes large and noise is expected to be reduced at high frequencies.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to inductors and molded inductors used in power supply circuits and signal systems of computers and the like.

0002

2. Description of the Related Art Generally, in order to reduce high frequency (10 MHz or higher) noise in a power supply circuit for a computer or the like, it is sufficient to insert an inductance in series with the circuit, and ferrite beads are used as such an inductance. For example, as shown in FIG.
It is constructed by passing a conducting wire 52 through 1a. The ferrite core 51 used in this ferrite bead has a noise removal effect by simply baking iron oxide powder and is compatible with a wide range of frequencies, so it is widely used for noise reduction in power circuits, signal systems, etc. has been done.

0003

By the way, the ferrite bead is manufactured by passing the ferrite core 51 through a conducting wire 52, and then inserting the ferrite core 51 into the conducting wire 52 so that the ferrite core 51 does not move.
After adhering to the ferrite core 51, the ferrite core 51 is taped. Note that, if necessary, the ferrite core 51 may be made of polybutylene terephthalate (PBT).
Alternatively, it is molded with polyphenylene sulfide (PPS) or the like.

[0004] However, it is difficult to completely automate the production of the ferrite beads since the above-mentioned complicated steps are involved, and it is also difficult to manufacture them into surface-mounted parts due to the cost. Therefore, the present invention has been proposed in view of the conventional situation, and an object thereof is to provide an inexpensive inductor and molded inductor that can be manufactured fully automatically and can be made into a surface-mounted component. It is something to do.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, an inductor of the present invention is formed from a plate made of a conductive material. Further, a molded inductor of the present invention is obtained by coating the inductor according to the first invention with a ferrite resin.

[0006]

[Operation] Since the inductor according to the present invention is formed by continuously molding a plate made of a conductive material by press working, it is possible to manufacture the inductor in one batch, and complete automation can be expected. Furthermore, the molded inductor according to the present invention includes the first
Since the inductor according to the invention is coated with ferrite resin, it can be used as a surface mount component. Also,
Since this molded inductor is manufactured by continuously coating the inductor according to the first invention with ferrite resin, it is possible to manufacture it completely automatically.

[0007]

[Embodiments] Specific embodiments to which the present invention is applied will be described below.

First Embodiment As shown in FIG. 1, an inductor 1 according to the first embodiment is formed by punching a plate made of a conductive material into a predetermined shape. . As shown in FIG. 2, for example, the inductor 1 is manufactured using a progressive mold in which a long plate material 2 made of phosphor bronze or the like having low electrical resistance, a so-called hoop material, is formed at a predetermined feeding pitch with respect to a feed hole 3. It is manufactured by continuous punching into a predetermined shape using P. The inductor 1 of this example is
The planar shape is zigzag so that the conductor length corresponds to a desired inductance, and both ends 4a and 4b of the zigzag conductor portion 4 are terminals connected to external terminals or the like. Note that both end portions 4a and 4b, which serve as terminals of the inductor 1, are connected to the plate material 2 in the longitudinal direction of the conductor portion 4.
It is formed by cutting the connection with.

Since the inductor 1 manufactured in this manner is formed by press working using a progressive die, it is possible to mass-produce the inductor 1 at once through automation, and it is expected to significantly reduce the manufacturing cost per inductor. Therefore, an inexpensive inductor can be provided.

Next, a molded inductor formed by coating the inductor 1 with ferrite resin will be explained. As shown in FIG. 3, this molded inductor 5 has a conductor 4 covered with a ferrite resin 6 except for both ends 4a and 4b which serve as terminals of the inductor 1. That is, by covering the zigzag-shaped conductor 4 with the ferrite resin 6, the inductance increases and the coil functions as a high-performance choke coil that can reduce noise at high frequencies. In this example, the ferrite resin 6 is formed into a rectangular parallelepiped so as to be suitable for functioning as a surface-mounted component.

The molded inductor 5 is transported to an injection molding machine in a wound state, that is, in a hoop state, from the continuously punched plate material 2 shown in FIG. 2, and as shown in FIG. The ferrite resin 6 is formed by insert molding the ferrite resin 6 one after another. The ferrite resin 6 covering the conductor 4 is made by kneading sintered ferrite powder with a polymer resin. Then, the molded inductor 5 is completed by cutting the connection portion of the conductor 4 coated with the ferrite resin 6 with the plate material 2, which becomes the terminal portion.

The molded inductor 5 manufactured as described above is continuously formed by insert molding the ferrite resin 6 into the conductor 4 which has been continuously molded by press working, so that automation can be achieved and the manufacturing cost per piece can be reduced. Significant cost reduction can be achieved. Therefore, it is possible to provide an inexpensive molded inductor, and it can also be used as a surface-mounted component.

Second Embodiment As shown in FIG. 5, the inductor 7 of this second embodiment is formed into a predetermined shape by sequentially punching and bending plates made of a conductive material. It is something. As shown in FIG. 6, for example, the inductor 7 is made by punching out and folding a hoop-shaped plate material 8 made of phosphor bronze or the like in succession at a predetermined feed pitch P with a feed hole 9 as a reference using a progressive die. It is made by forming a curve. In this example, the inductor 7 is formed by cutting a blank to have a conductor length that corresponds to the desired inductance, and forming a narrow conductor 10 connected to the remaining plate 8 by standing up and bending it. It is shaped like a spiral. Also, both end portions 10 of the inductor 7 are connected to the plate material 8 at the beginning and end of the winding of the conductor 10.
Terminals a and 10b are terminals connected to external terminals and the like. Note that both end portions 10a and 10b, which serve as the terminals, are formed by cutting the connection portion of the conductor 10 with the plate material 8 in the longitudinal direction.

The inductor 7 manufactured in this way is also formed by press working using a progressive mold as in the first embodiment, so mass production can be performed by automation, and the cost per inductor can be reduced. A significant reduction in manufacturing costs can be expected. Therefore, an inexpensive inductor can be provided, and the inductor 7 can be a surface-mounted component.

Next, a molded inductor in which the inductor 7 is coated with ferrite resin will be explained. As shown in FIG. 7, this molded inductor 11 has a conductor 10 covered with a ferrite resin 12 except for both end portions 10a and 10b which serve as terminal portions of the inductor 7. That is, by covering the spiral conductor 10 with the ferrite resin 12, the inductance is increased and it functions as a high-performance choke coil that can reduce noise at high frequencies. In the molded inductor 11 of this example as well, the shape of the ferrite resin 12 is a rectangular parallelepiped so as to be suitable for functioning as a surface mount component, similar to the previous example.

The molded inductor 11 is transported to an injection molding machine in a rolled state, that is, in a hoop state, from the continuously punched and bent plate material 8 shown in FIG. It is formed by insert molding the conductor 10 portions one after another. The ferrite resin 12 covering the conductor 10 can be the same as that used in the first embodiment. Then, by cutting the connection portion of the conductor 10 coated with the ferrite resin 12 with the plate material 2 that becomes the terminal portion, the molded inductor 11
complete.

The molded inductor 11 manufactured as described above is continuously formed by insert molding the ferrite resin 12 onto the conductor 10 which has been successively punched and bent by press working, so that automation can be achieved, and The manufacturing cost per piece can be significantly reduced. Therefore, it is possible to provide an inexpensive molded inductor.

[0018]

[Effects of the Invention] As is clear from the above explanation, since the inductor of the present invention is formed from a plate made of a conductive material, it can be mass-produced at once through complete automation, and it is possible to supply inexpensive products. can. Further, in the inductor of the present invention, the inductance can be easily changed by changing the length of the conductor within the same external shape, and an inductor having an inductance as required can be provided.

Furthermore, in the molded inductor of the present invention, since the inductor according to the first invention is coated with ferrite resin, it can be used as a surface-mounted component in power supply circuits of computers, etc., and can be used as a surface-mounted component to reduce noise at high frequencies. It is possible to reduce the In addition, the molded inductor of the present invention is manufactured by coating the inductor with ferrite resin while it is in the continuously molded hoop state, so it can be manufactured in one batch with complete automation, and it can be expected to significantly reduce costs, making it possible to use inexpensive parts. Supply is expected.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an inductor of a first embodiment.

FIG. 2 is a plan view showing a state in which the inductor of the first embodiment is blanked out, showing an intermediate stage in the process of manufacturing the inductor.

FIG. 3 is a perspective view showing a molded inductor of the first embodiment.

FIG. 4 is a perspective view showing a state in which the molded inductor of the first embodiment is coated with ferrite resin, showing an intermediate stage in the process of manufacturing the molded inductor.

FIG. 5 is a perspective view showing an inductor of a second embodiment.

FIG. 6 is a perspective view showing a state in which the conductor is bent into a spiral shape, showing an intermediate stage in the process of manufacturing the inductor of the second embodiment.

FIG. 7 is a perspective view showing a molded inductor of a second embodiment.

FIG. 8 is a perspective view showing a state in which the molded inductor of the second embodiment is coated with ferrite resin, showing an intermediate stage in the process of manufacturing the molded inductor.

FIG. 9 is a perspective view showing a conventional ferrite bead.

[Explanation of symbols]

1, 7...Inductor 2,8...Plate material 4, 10... conductor 5, 11...Molded inductor 6,12...ferrite resin

Claims (2)

[Claims] 1. An inductor formed from a plate made of a conductive material. 2. A molded inductor comprising the inductor according to claim 1 coated with ferrite resin.