JPH0229717Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a metal surface bonded capacitor suitable for use in noise suppressors or other electronic devices.

Conventionally, when a capacitor is provided in a metal case in a noise suppressor or the like, a structure has been adopted in which the bare capacitor is directly connected to the outer metal case and the inside of the case is molded with an insulating resin as necessary.

Figure 1 shows an example of a noise suppressor in which a bare capacitor is directly connected to an exterior metal case. In this figure, the exterior metal case 1 includes terminals 2A, 2B,
2C is attached, and a coil 3 and capacitors 4 and 5 are housed inside the case. Here, the capacitor 5 is a bare capacitor having an electrode on its surface, and the electrode on one side is directly soldered to the metal exterior case 1, and the electrode lead connected to the other electrode is connected to the terminal 2A and the coil 3, respectively. ing.
Note that the inside of the exterior metal case 1 is molded with an insulating resin 6 if necessary.

If the structure is as shown in FIG. 1, the capacitor 5 is directly connected to the exterior metal case 1, which has the advantage of improving high frequency characteristics, but at the same time, the following drawbacks occur.

(1) Cracks occur because the capacitor base is directly exposed to ambient temperature changes and temperature changes when the capacitor is installed.

(2) Mechanical shock to the outer case is applied directly to the capacitor base, causing a crack.

(3) It cannot be attached to the side of the case, and it is difficult to apply it to various cases.

(4) During assembly work, since the capacitor is handled as a bare capacitor, there is a risk that the electrical characteristics will be significantly deteriorated due to the adhesion of dust or dirt.

(5) Since the capacitor is attached directly to the case body, the stability of the capacitor base is poor and insulation failure is likely to occur.

In view of the above-mentioned points, the present invention aims to provide a metal surface-attached capacitor that can be easily soldered to a metal case or a metal plate and has good high frequency characteristics.

Embodiments of the metal surface attached capacitor according to the present invention will be described below with reference to the drawings.

In FIGS. 2 to 4, a metal surface-attached capacitor 10 includes an external fitting 11 and a capacitor base 1.
2 and an electrode lead fitting 13.
The external metal fitting 11 forms a bottomed cylindrical part 14 inside,
A soldering collar 15 is formed on the outside by folding back, and is set so that the bottom of the bottomed cylindrical portion 14 and the soldering collar 15 are located on substantially the same plane. The capacitor body 12 has electrodes 16 and 17 on both sides, and the electrode 16 is directly soldered to the bottom of the bottomed cylindrical portion 14 of the external metal fitting 11. The electrode 17 also has a pair of lead parts 18A,
An electrode lead fitting 13 having a diameter of 18B is connected and fixed by soldering. Then, the inside of the bottomed cylindrical portion 14 of the external fitting 11 is filled with an insulating resin 20. Note that as the capacitor base 12, a bare ceramic base having good high frequency characteristics or the like can be used.

According to the configuration of the above embodiment, the following effects can be achieved.

(1) Since the soldering collar 15 is formed on the external fitting 11, it can be easily fixed to a flat metal surface such as a metal case or a metal plate by soldering. Moreover, it is easy to install even when there are holes in the metal surface.

(2) Since the capacitor has a soldering collar 15, soldering can be performed at this portion, and the temperature shock during soldering does not affect the capacitor base 12 itself. Therefore, occurrence of cracks in the capacitor base 12 can be prevented. Similarly, the temperature shock on the outer periphery is also alleviated by the external metal fitting 11.

(3) Mechanical impact on the metal surface to which the capacitor is attached is also alleviated by the soldering collar 15 of the external fitting 11, and the capacitor base 12 can be protected from cracking.

(4) During assembly, only the capacitor itself is handled, making it easy to handle and less likely to attract impurities.

FIG. 5 shows the first application example of the present invention. This is an application of the metal surface attached type capacitor 10 shown in the above embodiment to a noise suppressor, and the metal surface attached type capacitor 10 is attached to the input/output terminal mounting surface on the side surface of the exterior metal case 30 of the noise suppressor. It is fixed by soldering. In this case, lead portions 18A and 18B of capacitor 10 are connected to input/output terminal 31 and coil 32, respectively. In this way, it is possible to provide the capacitor 10 very close to the input/output terminal 31, so it is possible to improve the attenuation characteristics of the noise preventer.

FIG. 6 shows a second application example of the present invention. In this case, the metal surface-attached capacitor 10 is connected to the metal base 40 by soldering, and the terminal board 41 and the coil 42 are connected to the lead portion 18 of the capacitor 10.
They are connected at A and 18B, respectively. This configuration also makes it possible to improve the attenuation characteristics and make full use of the features of the metal surface attached capacitor 10. In the above embodiment, the external fitting had a structure in which the soldering collar was formed by folding it back on the outside. It's okay. This case is shown in FIG. 7 as another embodiment of the present invention. In this figure, a metal surface sticking type capacitor 50 is composed of an external metal fitting 51, a capacitor base 52, and an electrode lead metal fitting 53.
No. 1 is machined so that the bottom of the bottomed cylindrical portion 54 and the soldering (or spot welding) collar 55 are made of a common metal plate. The electrode on one side of the capacitor base 52 is connected to the bottomed cylindrical part 54.
It is soldered directly to the bottom of the capacitor base 5.
An electrode lead fitting 53 is connected and fixed to the electrode on the other side of the 2 by soldering, and the inside of the bottomed cylindrical part 54 is filled with an insulating resin 60.

According to the configuration shown in FIG. 7, since the bottom of the bottomed cylindrical portion 54 of the external fitting 51 and the soldering collar portion 55 are made of a common metal plate, the high frequency characteristics are excellent.

As explained above, according to the present invention, it is easy to solder to metal surfaces such as metal cases and metal plates.
It is possible to obtain a highly reliable metal surface-attached capacitor that prevents adverse effects on the capacitor element.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view showing an example of the structure of a noise suppressor using a conventional bare capacitor, Fig. 2 is a front sectional view showing an example of the metal surface attached type capacitor according to the present invention, and Fig. 3 is a side sectional view showing an example of the structure of a noise suppressor using a conventional bare capacitor. FIG. 4 is an exploded perspective view of the same, FIG. 5 is a partial sectional view showing the first application example of the present invention, FIG. 6 is a perspective view showing the second application example, and FIG. 7 is a perspective view of the invention. FIG. 7 is a front cross-sectional view showing another embodiment. 10...Metal surface sticking type capacitor, 11...External metal fitting, 12...Capacitor base, 13...Electrode lead fitting, 14...Bottomed cylindrical part, 15...Soldering collar, 16, 17... Electrode, 18A, 18
B...Lead part, 20...Insulating resin.

Claims (1)

[Scope of utility model registration request] A bottomed cylindrical part is formed on the inside, and a soldering collar is integrally formed on the outside, and the bottom of the bottomed cylindrical part and the soldering collar are set to be located on substantially the same plane. a capacitor base having electrodes on both sides and one electrode connected to the inner bottom of the bottomed cylindrical part, and an electrode lead metal fitting connected to the other electrode of the capacitor base, A capacitor attached to a metal surface, characterized in that the bottomed cylindrical portion is filled with an insulating resin.