JPS5881319A - Inductance element for noise filter - Google Patents

Abstract

PURPOSE:To obtain a noise filter inductance element which increases the high frequency range of a noise to be eliminated, by providing a ferrite magnetic core with an electrode to be grounded. CONSTITUTION:A drum type ferrite core 61 wound with electric wire 62 or ferrite core 81 having a through hole 83 where electric wire 82 is inserted is provided with an electrode 64 or electrode plate 84 by plating, adhesion of a conductive plate, etc. Then, an earth line is soldered to the electrode 64 or electrode plate 84 to perform the by-passing of a high frequency component as a noise to the ground by utilizing the dielectric constant that the ferrite core has.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an inductance element for a noise filter, and particularly relates to an inductance element that widens the high frequency range of noise to be removed.

Conventional noise filters have been constructed by combining several terror coils and several capacitors. However, in the terror coil using ferrite in the conventional noise filter.

9. For example, several tens of MHz without using a capacitor.
The above-mentioned high-frequency noise attenuation effect could not be made large. The reason is that the magnetic properties μ′, μ“ of the ferrite core are
This is because the ferrite core acts as a dielectric, resulting in a decrease in impedance.

For this reason, it has been difficult to obtain a large amount of noise attenuation over a wide band.

The present invention provides an inductance element for a noise filter that overcomes the above-mentioned drawbacks.

That is, in order to utilize the dielectric constant of the ferrite magnetic core, an electrode is provided on the ferrite magnetic core by plating, adhesion of a conductive plate, etc. (1) For example, an earth line is soldered to the electrode, and the high frequency of )-Is is generated.

Bypass components to ground.

Figures 1 and 3 (2 are front views of conventional choke coils, and Figures 2 and 4 are side views of the conventional examples shown in Figures 1 and 3, respectively. Figure 5 is.

This is an equivalent circuit of the tech coil shown in FIG. 1. In FIG. 141, 11 is a ferrite magnetic core around which electric wire 12 is wound. In FIG. 3, reference numeral 31 denotes a ferrite magnetic core having nine through holes 33, and the through holes 33 have electric wires 32 and 32.
It goes through.

A front view of an embodiment of the invention is shown in FIG.

FIG. 7 is a side view of the same embodiment, and FIG. 10 is its equivalent circuit.

In FIG. 6, an electric wire 62 is wound around a drum-shaped ferrite core 61. As shown in FIG. The electrode 64 is connected to the ferrite core 61
and ground to the electrode 64. In Figure 8,
FIG. 7 shows a front view of another embodiment. FIG. 9 is a side view of the embodiment shown in FIG. 8. A ferrite core 81 having a through hole 83 has an electric wire 82 inserted thereinto, and an electrode plate 84 is attached to the surface of the ferrite core 81 by plating.

A choke coil according to the present invention and a conventional choke coil.

1 is a comparison diagram of attenuation characteristics with that of the first embodiment. People are traditional TeV
- Cucoil I + two, and B is.

This is about the fl-Kukoiltan of the present invention.

In B, even high frequency noise of 100 MHz or more can be removed.

[Brief explanation of the drawing]

Figure 1 is a front view of a conventional technology coil, and Figure 2 is a
5 is an equivalent value circuit, FIG. 3 is a front view of another conventional chiyuki-ku coil, FIG. 4 is a side view of the same, FIG. 6 is a front view of the embodiment, and FIG. 7 is the same. 10 is a side view, FIG. 8 is a front view of another embodiment, FIG. 9 is a side view of the same, and FIG. 11 is a diagram showing an example of frequency dependence of noise attenuation amount. . 11: Ferrite magnetic core, 12: Electric wire, 61: Ferrite magnetic core, 62: Electric wire. Agent Koji Kajiwara

Claims (1)

[Claims] 1. An inductance element for a noise filter comprising a ferrite core and an electric wire, wherein the ferrite core is provided with an electrode connected to earth.