JPH05335147A - Filter - Google Patents

Abstract

PURPOSE:To contrive a miniaturization of a filter circuit or an increase in the withstand current capacity of the circuit by a method wherein the filter circuit is dipped in a resin which undergoes state changes according to temperature. CONSTITUTION:A resin which undergoes state changes is used as a resin 2. Heat due to a copper loss which is generated by a coil 5 is dissipated to the outside in addition to radiation, by conduction at the time the time when the resin 2 is in the solid phase, by conduction of absorbed heat at the time of gelation of the resin 2 and by convection and conduction at the time of liquefaction of the resin 2. Thereby, the heat dissipation of a filter circuit at the time of a high temperature is improved compared to that of a conventional filter circuit, a withstand current capacity of the filter circuit is increased at the time of the same copper loss and an increase in the copper loss becomes possible in the same current capacity. Even in any case, a miniaturization of 10 to 50% of the volume of the filter circuit can be contrived compared to the volume of the conventional filter circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter used in an electric circuit.

[0002]

2. Description of the Related Art In a conventional filter, a coil, or a coil and a basic circuit composed of additional parts such as a capacitor and a resistor, are placed in a bare or metal case.

[0003]

The conventional filter as described above has a problem that it cannot be downsized because there is no effective means for dissipating heat (mainly copper loss due to the coil) generated during energization. there were.

The present invention has been made in order to solve the above-mentioned problems, and an object thereof is to obtain a filter which can be downsized.

[0005]

A filter according to the present invention is one in which a filter circuit is immersed in a resin whose state changes with temperature.

[0006]

In the present invention, the heat generated from the circuit portion is dissipated by the (melting) heat absorption at the start of melting of the resin and by the convection at the liquefaction.

[0007]

【Example】

Example 1. Embodiment 1 of the present invention will be described with reference to FIGS. 1, 2 and 6. 1 is a diagram showing a cross section of a first embodiment of the present invention. FIG. 2 is a diagram showing a circuit according to the first embodiment of the present invention. Further, FIG. 6 is a diagram showing a state change of the resin of Example 1 of the present invention.

In FIG. 1, the first embodiment of the present invention comprises a magnetic core 1, a resin 2, a metal case 3, a terminal / terminal plate 4, and a coil 5.

As the resin 2, a resin whose state changes, an example of which is shown in FIG. 6, is used. In addition to radiating the heat caused by the copper loss generated from the coil 5, when the resin 2 is solid, it conducts, when it gels, it absorbs and conducts heat, and when it liquefies, it radiates to the outside by convection and conduction.

Therefore, the heat dissipation at a high temperature is improved as compared with the conventional case, the withstand current capacity can be increased at the same copper loss, and the copper loss can be increased at the same current capacity.
It is possible to reduce the volume by 50%.

As this type of resin 2, there is a urethane type resin, and a resin having a urethane content of 60% or more is used.

The first embodiment of the present invention, as described above,
In order to reduce the size or increase the withstand current capacity, the internal coil portion is immersed in the resin 2 that changes into three states depending on the temperature to improve heat dissipation. 1 for the same current capacity
There is an effect that the size can be reduced by 0 to 50% and the current capacity can be increased by 5 to 30% in the same volume.

Embodiment 2. Although only the coil 5 is shown in the metal case 3 in the above-described first embodiment, as shown in FIG. 3, an additional component 6 such as a capacitor is mounted on the substrate 7, and as shown in FIG. The same operation can be expected by immersing the coil 5 of the filter having the circuit function.

Example 3. Further, as shown in FIG. 5, the metal case 3 may be provided with a heat dissipating portion 8 having a wide surface area composed of an uneven portion to improve heat dissipation, and the same operational effect as that of the above-described first embodiment is obtained. Needless to say, the intended purpose can be achieved.

[0015]

As described above, according to the present invention, the coil is immersed in the resin which changes its state depending on the temperature, so that there is an effect that the size can be reduced.

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment of the present invention.

FIG. 2 is a circuit diagram showing a first embodiment of the present invention.

FIG. 3 is a diagram showing a second embodiment of the present invention.

FIG. 4 is a circuit diagram showing a second embodiment of the present invention.

FIG. 5 is a diagram showing a third embodiment of the present invention.

FIG. 6 is a diagram showing a change in state of a resin according to each embodiment of the present invention.

[Explanation of symbols]

 1 magnetic core 2 resin 3 metal case 4 terminal and terminal plate 5 coil 6 additional parts 7 substrate 8 heat sink

Claims (6)

[Claims] 1. A filter comprising a coil immersed in a resin which becomes solid at room temperature and becomes liquid at high temperature. 2. A coil immersed in a resin that becomes solid near room temperature and liquid at high temperature, and absorbs heat when the resin melts, and convection, conduction, and radiation 3 when liquefying. A filter characterized by utilizing the heat dissipation and heat transfer effects of. 3. A coil immersed in a resin that becomes solid at room temperature and becomes liquid at high temperature, the resin and the coil being housed in a metal case, and the amount of heat generated in the metal case is the metal. A filter characterized in that heat is dissipated to the outside through the case. 4. A coil is immersed in a resin that becomes solid at around room temperature and becomes liquid at high temperature. The resin is prevented from leaking by solidifying the resin when not energized, and the resin is removed only when energized. A filter characterized by exhibiting a heat dissipation function by being liquefied. 5. A metal case, which comprises a coil immersed in a resin that becomes solid near room temperature and becomes liquid at high temperature, and the resin and the coil are housed in a metal case having a heat radiation structure provided on the surface thereof. A filter, wherein the amount of heat generated inside is transferred to the outside through the metal case. 6. A coil immersed in a resin which becomes solid at room temperature and becomes liquid at high temperature, and has a coil ratio of 30
A filter having a volume reduction of -60%.