JPS5919433Y2 - 4-terminal electrolytic capacitor - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a low-impedance four-terminal electrolytic capacitor in which the electrode lead-out portion of the capacitor element is redesigned and a small-capacity flat plate capacitor is provided in the electrode lead-out portion.

Conventionally, a low impedance electrolytic capacitor constructed as shown in FIG. 1 is known.

That is, as shown in FIG. 1A, the anode foil 5 and the cathode foil 6 are shifted from each other and wound in a non-inductive manner with the electrolytic paper 10 in between, to produce the flat element 4.

Next, as shown in the opening of the figure, a plurality of flat elements 4 are stacked, and the anode foil 5 is pressed onto the anode extraction electrode plate 1, and the cathode foil 6 is pressed onto the cathode extraction electrode plate 2, and then welded or soldered 7. Connecting.

At this time, the flat element 4 is attached to both sides of the electrode plates 1 and 2, as shown in FIG.
This is an insulating separator between the two.

In this configuration, an oxide film is formed on the anode foil, so when the capacitor element 4 is flattened or connected to the anode extraction electrode plate 1 by welding or the like, the oxide film may deteriorate or be damaged, causing leakage current. Easy to increase.

Alternatively, since the electrolytic capacitor element 4 is flat, when multiple electrolytic capacitor elements 4 are stacked and attached to the electrode plate, the central part 4a of the element 4
This increases tanδ or impedance due to a drop in the structure, and the structure becomes complicated due to the need for clamping fittings for the element.
It had many drawbacks, including high manufacturing costs.

The present invention eliminates the above-mentioned drawbacks and significantly improves the impedance characteristics at high frequencies.This will be explained with reference to an embodiment of the connection structure of an electrolytic capacitor element shown in FIGS. 2 and 3. The cathode foil 6 is wound into a cylindrical shape with an electrolytic paper 10 in between to form an electrolytic capacitor element 14.

The electrode tab 8 is connected to the anode foil 5, the electrode tab 9 is connected to the cathode foil 6, and the electrode tab 8 is connected to the anode foil 5 as shown in the opening of FIG.
and 9 are pulled out in opposite directions.

Next, a plurality of electrolytic capacitor elements 14 are stacked one on top of the other so that the polarities of the electrode tabs are in the same direction, and are connected to the plate-shaped lead-out electrode plates 1 and 2, respectively.

That is, the electrode tab 8 is welded 7 to the anode extraction electrode plate 1,
The electrode tab 9 is welded 7 to the cathode extraction electrode plate 2.

Reference numeral 3a denotes a dielectric material sandwiched between the extraction electrodes 1 and 2, and the material used is Mylar, polypropylene, polyethylene terephthalate, polycarbonate, electrolytic paper impregnated with an electrolytic solution, or the like.

A capacitor having a small capacitance impedance characteristic is formed by the lead electrode plates 1 and 2 sandwiching the dielectric 3a.

A plurality of capacitor elements 14 are connected in parallel on both sides of the extraction electrode plates 1 and 2 as shown in the second part.

However, if the rated capacity is small, it may be connected only to one side.

In FIG. 3A, the capacitor element 14 shown in FIG. 2 is a pair of plate-shaped extraction electrode plates 1 and 2 having an input extraction piece 21.22 and an output extraction piece 23.24 provided at a predetermined distance.
21.22゜23, 24 above.
Four drawer pieces are formed.

The opening in FIG. 3 is constructed by extending the dielectric 3a between the opposing electrodes of the lead-out pieces 21 and 22, and 23 and 24 in order to reduce the inductance of the lead-out pieces.

Figure 4 shows the input pull-out piece 21 provided on the pull-out electrode plate in Figure 3.
．． 22 and output pull-out pieces 23 and 24 are connected to input terminals 25 and 26 and output terminals 27 and 28 fixed to the sealed terminal board 11, and as shown in FIG. Store it in and complete it.

In other words, the present invention utilizes the principle that when n electrolytic capacitor elements are connected in parallel, the impedance of the completed electrolytic capacitor is l/n, ignoring the impedance of the connecting electrodes, and the terminal for human power and the terminal for output. By providing a four-terminal type, high-frequency impedance is reduced.

In general, audio amplifiers that use switching power supplies remove noise generated during high-speed switching using a circuit configuration as shown in Figure 6, but if the high frequency characteristics of the electrolytic capacitor for the filter are poor, the filtering effect will be small. in,
It had a large effect on the outside as noise, and also had a large effect on the output of the amplifier.

Therefore, to reduce these, large capacitors and large inductances are required, which causes high costs, and to improve the high frequency range in sound quality, low loss capacitors 2.
9.30 are connected in parallel, but the present invention improves this and connects the above-mentioned electrolytic capacitor element 14 as shown in FIG.
4-terminal electrolytic capacitor 17 connected in parallel.
．． Since it has a structure in which low-loss flat capacitors 19 and 20, which are made up of extraction electrode plates 1 and 2 and a dielectric material 3a, are connected in parallel with 18, it is possible to improve the sound quality in the high range, and it is possible to improve the sound quality in the high frequency range. Since the filter effect can be sufficiently increased using inductance, the cost of parts can be significantly reduced.

Next, as an example, an electrode foil with a width of 30 mm and a length of 800 mm was wound through electrolytic paper to obtain a rated capacitance of 1000μ.
F. Obtain an electrolytic capacitor element with a rated voltage of 50V, and connect this capacitor element in parallel with two aluminum electrode plates for anode and cathode, 10 pieces on one side and 10 pieces on the other side, with a dielectric interposed between them. When connected, the rated capacitance is 20000μF,
An electrolytic capacitor of the present invention having a rated voltage of 50 V was manufactured, and the frequency-impedance characteristics were measured. The results are shown in FIG.

Furthermore, as a result of measuring the leakage current, it was found to be 40 to 80 μA, which was less than the conventional Ho.

As is clear from FIG. 8, it was found that the impedance value at high frequencies of the present product was significantly reduced compared to the conventional product, and it was confirmed that the sound quality was also superior.

In addition, since the electrolytic capacitor of the present invention does not need to be wound non-inductively to form a flat element, the dimensions of both ends of the anode foil and cathode foil can be designed to be short, reducing the amount of material used. Therefore, it is easy to wind up, and processing such as flattening and tightening is not required, reducing working time and manufacturing costs by 30%.

As described above, the present invention includes a flat capacitor formed of a pair of electrode plates having an input lead piece and an output lead piece that sandwich a dielectric material and are spaced apart from each other by a predetermined distance, and a plate capacitor connected to the electrode plate. A four-terminal electrolytic capacitor consisting of multiple capacitor elements with electrode tabs pulled out in opposite directions.It reduces leakage current and greatly reduces impedance at high frequencies, making it ideal for ripples in switching regulators, audio amplifiers, etc. It is suitable for filtering circuits that draw large currents and generate high-frequency noise, and is suitable for improving sound quality.It is inexpensive and can improve productivity, so it has great practical value.

[Brief explanation of drawings]

Figure 1 shows a conventional electrolytic capacitor, where A is a perspective view of a flat element wound in a non-inductive manner, the opening is a perspective view of multiple flat elements of A stacked together and connected to an extraction electrode plate, and C is an illustration. 2 to 5 show an embodiment of the electrolytic capacitor of the present invention, and FIG. 2A is an exploded perspective view of the electrolytic capacitor element. The opening in Figure 2 is a perspective view of a wound cylindrical electrolytic capacitor element, Figure 2 C is a perspective view of a plurality of cylindrical elements assembled and connected to an extraction electrode plate, and the second part is the cylindrical shape of the opening. A plan view of a plurality of elements assembled and connected to an extraction electrode plate, Figure 3A is a perspective view of the extraction electrode plate of Figure 2 with an input extraction piece and an output extraction piece, and the opening of Figure 3 is the drawer of A. A perspective view of the inductor extending to one side, Figure 4 A 9 is a perspective view of Figure 3 A 9 being fixed to the sealed terminal board, Figure 5 A 9 is a perspective view of Figure 4 A 1 being fixed to the case, respectively. Fig. 6 is a circuit diagram of an example of a conventional switching power supply, Fig. 7 is a circuit diagram of an example of a switching power supply using the product of the present invention, and Fig. 8 is a perspective view of a completed four-terminal electrolytic capacitor housed in a 4-terminal electrolytic capacitor. FIG. 3 is an impedance-frequency characteristic diagram showing a comparison between a product of the present invention and a conventional product. 1.2: Extracting electrode plate, 3a: Dielectric, 8, 9: Electrode tab, 14: Capacitor element, 17.18: 4-terminal electrolytic capacitor, 19.20: Flat plate capacitor, 21゜2
2: Input terminal piece, 23, 24: Output terminal piece.

Claims (1)

[Scope of utility model registration request] A flat capacitor formed of a pair of lead-out electrode plates having an input lead-out piece and an output lead-out piece sandwiching a dielectric material and separated by a predetermined distance; A four-terminal electrolytic capacitor comprising a plurality of cylindrical capacitor elements arranged side by side on the lead-out electrode plate.