JPS5940761Y2 - Electrolytic capacitor - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an electrolytic capacitor, which is suitable for, for example, audio equipment and is capable of reducing third-order harmonic distortion and obtaining high-fidelity sound quality.

As is well known, electrolytic capacitors are incorporated into various circuits that make up audio equipment, such as smoothing the rectified output of power supplies, bypassing signals in amplifier circuits, and coupling. is known to be affected by

fjf! Regarding third-order harmonic distortion, which is considered to be a problem in terms of sound quality, it is necessary to suppress the generation of third-order harmonic distortion by electrolytic capacitors in order to achieve high fidelity.

The purpose of this invention is to reduce the occurrence of third harmonic distortion,
The present invention provides an electrolytic capacitor suitable for audio equipment circuits.

Kono's idea is to provide a second anode aluminum foil with a smaller area than the anode aluminum foil by interposing a separator between the anode aluminum foil and the cathode aluminum foil, and to use the second anode aluminum foil for connection. It is characterized by having an anode terminal of.

Hereinafter, one embodiment of this invention will be described in detail based on the drawings.

FIG. 1 shows an embodiment of the electrolytic capacitor of this invention.

As shown in Fig. VC button, a sealing rubber 4 is inserted into the opening of the bottomed cylindrical case 2 which is integrally molded from an aluminum plate, and the opening end of the case 2 is crimped. In addition to being firmly held, the open end of the case 2 is curved inward and exposed to the upper surface of the sealing rubber 4.

The case 2Vc sealed with the sealing rubber 4 is sealed with an aluminum electrolytic capacitor element 6, and has a first anode tab 8, a second anode tab 10 and a cathode tab led out from the aluminum electrolytic capacitor element 6. The tab 12 is a first anode terminal 14 which is held through the sealing rubber 4;
It is fixed to the second anode terminal 16 and the polarization terminal 18, respectively.

As shown in FIG. 2, the aluminum electrolytic capacitor element includes a conventionally used first anode aluminum foil 20, a cathode aluminum foil 22, and a separator 24, each of which has a dielectric formed by a chemical oxide film on its surface. ,26
In addition, a second anode aluminum foil 28 and a separator 30 having a surface formed with a dielectric film made of a chemical oxide film and having a smaller area than the first anode aluminum foil 20 and a separator 30 are provided and formed by winding. It is interposed between the first and second anode aluminum foils 20.28.

And the first and second anode aluminum foils 20°28
Further, the first and second anode tabs 8 and 10 and the cathode tough 12 are fixed to the cathode aluminum foil 22.

With the above configuration, the equivalent circuit of the electrolytic capacitor shown in Figs. 1 and 2 is as shown in Fig. 3.
A second anode 28A can be provided between the anode 20A and the cathode 22A.

As a result, the capacitance due to the first anode 20A is formed on the surface of the cathode 22A facing the first anode 20A, and as described above, the second anode aluminum foil 28 is
Since the area is smaller than that of the anode aluminum foil 20,
Its capacitance is much smaller than the capacitance between the first anode 20A and the cathode 22A.

Note that bringing the length of the second anode aluminum foil 28 closer to the first anode aluminum foil 20 means a reduction in the effective area of the first anode aluminum foil 20, resulting in a decrease in capacitance. The area of the second anode aluminum foil 28 is required to be small.

Next, the case where the electrolytic capacitor of this invention is used in audio equipment will be explained.

The circuit shown in FIG. 4 is an experimental circuit for a capacitor, and was constructed to observe third-order harmonic distortion.

As shown in the figure, a signal source 32 that outputs a signal with a frequency of 10 KHz is applied between the first anode 20A and the cathode 22A, and a bias DC power supply 34 is applied between the second anode 28A and the cathode 22A. Power is being supplied.

For example, if the rating of an electrolytic capacitor is 63V, 18,00
0 μF(7)mo(7)fahha, 1. The output voltage of the current power source 34 is one that can output at a rating of 63.1.

Output terminals 36A and 36B are provided between the first anode 20A and the cathode 22A, and the output terminals 36A and 36BK
Let us detect and consider the third harmonic distortion in the output signal that appears.

By pressing a button on such a circuit, the output voltage of the DC power supply 34 is
In other words, when no DC voltage is applied, third harmonic distortion corresponding to the input as shown in FIG. 5AK is detected.

Next, when the output voltage of the DC power supply 34 is set to 30V,
Third harmonic distortion corresponding to the input as shown in FIG. 5B is detected, and FIG. 5C shows the case where the output voltage of the DC power supply 34 is 63V.

In this way, the output voltage of the DC power supply 34 causes the second anode 28A to
It can be understood that by applying a bias between the output terminals 36A and 22A, the third harmonic distortion in the output signal appearing between the output terminals 36A and 36B is reduced, and the rate of reduction is related to the DC applied voltage. .

However, it has been confirmed that increasing the DC output voltage above the rated voltage has the opposite effect.

If a predetermined DC bias is applied between the second anode 28A and the cathode 22A and used in various circuits constituting audio equipment, the sound quality due to third harmonic distortion that occurs in conventional electrolytic capacitors can be improved. The degradation or loss of fidelity can be easily remedied.

Furthermore, the structure of the electrolytic capacitor is extremely simple, simply adding the second anode aluminum foil 28 and the separator 30 to the conventional product, so it maintains the conventional reliability and has effective characteristics. can be obtained.

In addition, since the surface area of the second anode aluminum foil 28VC is enlarged by etching, the size of the aluminum foil can be small, manufacturing is extremely easy, and it can be provided at the same price as conventional products. .

In addition, in the case of this example, the second anode aluminum foil 2
8 is a separator 30 on the surface of the first anode aluminum foil 200.
However, the same effect can be obtained by contacting the surface of the cathode aluminum foil 22 with the separator 30 interposed therebetween.

As explained above, according to this invention, since the second anode aluminum foil is provided, it can be configured as a circuit that can reduce the generation of third harmonic distortion, and can be incorporated into the circuit of audio equipment to achieve high fidelity. You can get good sound quality.

Moreover, since this electrolytic capacitor can be constructed extremely easily, it can be provided at low cost.

[Brief Description of the Drawings] Fig. 1 is a longitudinal sectional view showing an embodiment of the electrolytic capacitor of this invention, Fig. 2 is a perspective view showing the structure of an aluminum electrolytic capacitor element, and Fig. 3 is an explanation showing its equivalent circuit. 4 is a circuit diagram showing an experimental circuit, and FIG. 5 is an explanatory diagram showing third harmonic distortion characteristics. 6... Aluminum electrolytic capacitor element, 16
...Second anode terminal, 20...First
Anode aluminum foil, 22... Cathode aluminum foil, 2426, 30... Separator, 28.
...Second anode aluminum foil.

Claims (1)

[Claims for Utility Model Registration] 11. An electrolytic capacitor comprising an electrolytic capacitor element formed by winding an anode aluminum foil having a chemical oxide film formed on its surface and a cathode aluminum plate with a separator interposed therebetween, wherein the anode A separator is interposed between the aluminum foil and the cathode aluminum foil to provide a second anode aluminum foil having a smaller area than the anode aluminum foil, and an anode terminal for connection is provided on the second anode aluminum foil. An electrolytic capacitor characterized by: 2. The electrolytic capacitor according to claim 1, wherein the second anode aluminum foil has a chemical oxide film formed on its surface.