JPS6032758Y2 - Block type capacitor - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to improvements in block capacitors, and particularly provides a block capacitor that has excellent performance as an acoustic capacitor.

In general, capacitors used in audio equipment are designed specifically for acoustic use, as it is necessary to faithfully reproduce audio signals, and their performance is as follows:
It has low impedance over a wide frequency band (D, C to IMH2), has a sufficiently low distortion rate as a single unit, and generates little leakage flux when incorporated into a circuit, which affects the distortion rate as an audio device. Characteristics such as those that do not occur are required.

For example, aluminum electrolytic capacitors used for smoothing the power supply of stereo amplifiers are used not only for the original purpose of supplying power to the amplifier, but also as part of the signal path. It is required that the power supply impedance is sufficiently low and flat with respect to the frequency and the ability to follow the frequency sufficiently.

In particular, the power supply supplied to the final stage of a power amplifier handles a large current, and changes in load current due to sudden changes in signals are large, so it is important not only to have a large capacity for smoothing, but also to have impedance characteristics. Become.

Furthermore, the increase in impedance at high frequencies is due to the inductance component, and if the inductance component is large, there is a risk that it will not be possible to cope with rapid current changes.

Therefore, many studies have been made to reduce the inductance component and improve the characteristics of aluminum electrolytic capacitors used for applications requiring high frequency performance, including acoustic applications.

For this reason, it is not possible to completely eliminate the inductance component in aluminum electrolytic capacitors with a structure in which conventional strip-shaped electrode foil is wound, but by adjusting the position and number of lead leads, it hardly becomes a problem in practice. It was possible to improve the characteristics to the standard, achieving low impedance and flatness up to high frequencies.

For example, as shown in FIG.
Rather than pulling out from the edge, by pulling out from the center as shown in Figure 2, or pulling out multiple pieces as shown in Figure 3,
As shown in Figure 4, the frequency characteristics can be significantly improved, but in this case, the winding tightening must be adjusted extremely strictly, otherwise it will be difficult to pull out the lead from a certain position, resulting in high production efficiency. This is not a good idea from an industrial perspective.

If a large number of leads do not come out from a fixed position, the anode lead and the cathode lead may cross each other, causing a short circuit failure, which is unacceptable.

Note that in FIG. 4, characteristics A, B, and C are frequency characteristics corresponding to FIGS. 1, 2, and 3, respectively.

Therefore, in order to actually industrially produce a product with such an effect, it is necessary to use a small-capacity aluminum electrolyte with a single intermediate lead, which has the simplest structure and is easy to manufacture, as shown in Figure 5. It is thought that it is better to create a capacitor 3 and connect it in parallel to form a block.

In this way, it is possible to solve the difficult production problem of improving frequency characteristics by pulling out a large number of leads, but in practical terms, the external terminal 4 as an electronic component and the individual aluminum electrolytic capacitor 3 can be solved. There still remains the problem that the magnetic flux generated when current flows through the line 5 that electrically connects between the two leaks and affects the distortion factor of the amplifier.

This invention was developed in view of these problems,
By changing the lines that electrically connect the individual aluminum electrolytic capacitors that make up the capacitor block and external terminals from conventional wires to flat wiring using printed circuit boards,
By reducing line inductance and keeping the distance between individual aluminum electrolytic capacitors and external terminals at a minimum, it was possible to reduce the generation of magnetic flux.

Below, the sixth section regarding the block type capacitor according to the present invention will be explained.
This will be explained using figures.

In the figure, 6 is a small capacity aluminum electrolytic capacitor equipped with an anode lead 7 and a cathode lead 8, 9 is a printed circuit board having an anode pattern 10, a cathode pattern 11, and a common pattern 12. As for the common pattern 12, in FIG.
A common pattern 12 is formed to surround the anode pattern 10 and the cathode pattern 11 with a narrow insulation gap 13 of 271El11 or less being formed around the anode pattern 10 and the cathode pattern 11.

Further, the anode lead 7 of each of the plurality of aluminum electrolytic capacitors 6,
A through hole 14 into which the cathode lead 8 is inserted is provided, and an anode external terminal 15. A cathode external terminal 16 and a common external terminal 17 are electrically connected to the respective patterns and mounted in a concentrated manner in the center.

Now, if we consider the four aluminum electrolytic capacitors 6 shown by solid lines in Figure 6, these aluminum! The anode lead 7 of the electrolytic capacitor 6 is connected to a common pattern 12, and the common pattern 12 essentially becomes an anode pattern for the four aluminum electrolytic capacitors 6 shown in solid lines.

Further, when considering four aluminum electrolytic capacitors 6 shown by dotted lines, the common pattern 12 substantially becomes a cathode pattern.

In the example shown in Fig. 6, blocks of four aluminum electrolytic capacitors connected in parallel are further connected in series, and common pattern 12 is used, but a common pattern is necessary when connecting in parallel. Instead, it is sufficient to provide only the anode pattern 10 and the cathode pattern 11.

In the present invention, a plurality of aluminum electrolytic capacitors 6 as shown in FIG. 6 are assembled into a printed circuit board 9, and the aluminum electrolytic capacitors 6 are placed inside a resin outer case (not shown), and the printed circuit board 9 is inserted into the opening of the outer case. They are fitted and stored, and a thermosetting resin such as epoxy resin is injected onto the printed circuit board 9 and cured to close the opening of the outer case to complete the finished product.

In order to confirm the effect of the block type capacitor of the present invention constructed in this way, a block type capacitor with a rating of 63V and 22000μF was created by blocking four aluminum electrolytic capacitors, and this block type capacitor was directly connected to two power supplies. When two of these were used in a type 5EPP α1 circuit, the distortion factor of the amplifier was 1/2 that of the conventional CP line.

As is clear from the above description, the block type capacitor according to the present invention connects the plurality of aluminum electrolytic capacitors 6 and external terminals in a planar manner by using the printed circuit board 9 which functions as a sealing plate for the outer case. This method connects electrical wiring between six aluminum electrolytic capacitors, compared to conventional connections using CP wires.
The line between the aluminum electrolytic capacitor 6 and the external terminal is shortened, and the inductance in the line can be reduced, as well as the generation of magnetic flux.

Furthermore, since the printed circuit board 9 is used, the work of assembling a plurality of aluminum electrolytic capacitors 6 is extremely easy, and workability can be improved, and the product can be manufactured at low cost.

Further, as explained in the above embodiment, the anode pattern 10
By keeping the insulation gap 13 between the cathode pattern 11 and the common pattern 12, that is, between the anode and cathode pattern portions of the printed circuit board 9 narrow to 2m+++ or less, the aluminum electrolytic capacitor 6 itself The generation of leakage magnetic flux in the anode lead 7 and cathode lead 8 can be reduced, and the above-mentioned effects can be further enhanced.

Note that it is our experience that the insulation gap between each pattern is 2 mm or less, and by setting the insulation gap to 2 periods or less, the generation of leakage magnetic flux can be reduced.

Furthermore, by concentrating the anode external terminal 15, the cathode external terminal 16, and the common external terminal 17 in the center of the printed circuit board 9, the characteristics of the power transistor can be improved when used in the 5EPP type α1 circuit described above. It is less likely that variations will occur.

Incidentally, as shown in FIG. 7, a similar effect can be obtained when a plurality of aluminum electrolytic capacitors are simply connected in parallel.

As described above, according to the block type capacitor of the present invention, when used in audio equipment, the distortion rate can be extremely low, audio equipment with excellent performance can be obtained, and productivity can be improved. It has extremely high practical value, as it can be used at low cost.

[Brief explanation of the drawing]

Figures 1 to 3 are plan views showing examples of how to attach a lead to an anode foil used in a wound aluminum electrolytic capacitor, and Figure 4 is an example of how to attach a lead to an anode foil used in a wound aluminum electrolytic capacitor. is a frequency-impedance characteristic diagram of the structure, FIG. 5 is a perspective view showing the main parts of a conventional block type capacitor, and FIGS. 6 and 7 each show the main parts of a block type capacitor according to an embodiment of the present invention. It is an exploded perspective view. 6... Aluminum electrolytic capacitor, 7...
Anode lead, 9... Cathode lead, 9...
Printed circuit board, 10... Anode pattern, 11.
... Cathode pattern, 12 ... Common pattern 1.13 ... Insulation gap, 15 ... Anode external terminal, 16 ... Cathode external terminal , 17...
...Common external terminal.

Claims (2)

[Scope of utility model registration request] (1) An outer case, a plurality of capacitors housed in the outer case and having an anode lead and a cathode lead, and a printed circuit board fitted into an opening of the outer case, An anode pattern and a cathode pattern to which the anode leads and cathode leads of a plurality of capacitors are electrically connected are provided, and the plurality of capacitors are electrically wired in a plane using this printed circuit board, thereby reducing magnetic flux leakage during operation. A block type capacitor characterized by preventing the occurrence of. (2) Utility model registration according to claim 1, in which the anode external terminal and the cathode external terminal, which are connected to the anode pattern and the cathode pattern on the printed circuit board and drawn out to the outside, are concentrated in the center of the printed circuit board. block type capacitor.