JP2000348990A - Inspection device for electrolytic capacitor and inspection method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the inspection device for an electrolytic capacitor, which can detect shorting due to dropped parts of the cut burrs of a cathode foil and an anode foil, which occurs only seldomly by the use conditions of the electrolytic capacitor, in the initial inspection of the electrolytic capacitor and can improve the quality of the electrolytic capacitor, and to provide an inspection method using the device. SOLUTION: For an inspection device, an inrush current supply capacitor C1, a power source PS1 charging the inrush current supply capacitor C1 and a backup capacitor C2 are installed, and a charging resistor R2 is installed between the backup capacitor C2 and the inrush current supply capacitor C1 in series. Inrush current is applied to a test electrolytic capacitor Cs, and the change of voltage or current is inspected. Thus, shorting due to dropped parts of cut burrs on a cathode foil and an anode foil, which occurs only seldomly, can be detected, and an electrolytic capacitor of high quality can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inspection apparatus for an electrolytic capacitor used in various electronic devices and an inspection method using the same.

[0002]

2. Description of the Related Art Generally, as shown in FIG. 3, an electrolytic capacitor is wound with separators 5 and 6 by connecting lead wires 3 and 4 to an anode foil 1 and a cathode foil 2 cut to a predetermined size by a slitter. After the capacitor element 7 formed by impregnating the electrolyte for use (not shown) is housed in a cylindrical metal case (not shown) having a bottom, the lead wires 3 and 4 led out from the capacitor element 7 are removed. After penetrating through a sealing plate (not shown), the open end of the metal case is squeezed and sealed together with the sealing plate.

In the electrolytic capacitor thus manufactured, a higher quality electrolytic capacitor is obtained by repairing and forming the anode foil 1 by aging.

[0004]

However, such an electrolytic capacitor is provided with an anode foil 1 cut to a predetermined size.
The cut surface of the cathode foil 2 has fine cutting burrs 8 as shown in FIG. The fine cutting burr 8 may fall off and be involved in the process of winding through the separators 5 and 6. The electrolytic capacitor in such a state does not cause any problem at a voltage of about aging, but has a problem that a short-circuit may occur at a falling part of the cutting burr 8 depending on use conditions when used in a set product. I have.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and finds a short circuit due to a cut-off portion of a cutting burr of an anode foil and a cathode foil which is rarely caused by the use condition of an electrolytic capacitor in an initial inspection of the electrolytic capacitor. It is an object of the present invention to provide an electrolytic capacitor inspection apparatus and an inspection method using the same, which can improve the quality of the electrolytic capacitor.

[0006]

In order to solve the above-mentioned problems, the present invention provides an inrush current supply capacitor arranged in parallel with a test electrolytic capacitor via a resistor, and a power supply for charging the inrush current supply capacitor. And a backup capacitor, and a test device with a charging resistor in series between the backup capacitor and the inrush current supply capacitor.The inrush current is applied to the test electrolytic capacitor up to the rated voltage or surge voltage. Thus, a change in voltage or current after charging is inspected.

According to the present invention, it is possible to detect short-circuits caused by falling-off portions of cutting burrs of the anode foil and the cathode foil, which are rarely caused depending on the use conditions of the electrolytic capacitor, in the initial inspection of the electrolytic capacitor, thereby achieving high reliability. An electrolytic capacitor is obtained.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is directed to an inrush current supply capacitor disposed in parallel with a test electrolytic capacitor via a resistor, and a power supply for charging the inrush current supply capacitor. A backup capacitor is provided, and a charging resistor is provided in series between the backup capacitor and the inrush current supply capacitor. With this configuration, the current capacity of the charging power supply can be reduced, and the inrush current supply This has the function of gradually accumulating charge in the capacitor and discharging a large current to the test electrolytic capacitor at a stretch.

According to a second aspect of the present invention, in the first aspect of the present invention, the capacitance of the inrush current supply capacitor is four times or more the size of the test electrolytic capacitor. It has the effect that it can be suppressed.

According to a third aspect of the present invention, in the first or second aspect of the invention, the capacity of the backup capacitor is four times or more the capacity of the inrush current supply capacitor. Can be suppressed.

According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, an inrush current is applied to the test electrolytic capacitor up to a rated voltage or a surge voltage, and after the battery is charged. It is designed to inspect the change of voltage or current.Electric capacitor can be inspected with high accuracy by gradually storing electric charge in inrush current supply capacitor and discharging large current to test electrolytic capacitor at once. It has the action of:

According to a fifth aspect of the present invention, in the invention of the fourth aspect, the test is performed by applying an inrush current of 30 A or more to the test electrolytic capacitor. Can be increased.

According to a sixth aspect of the present invention, in the invention of the fourth or fifth aspect, the test electrolytic capacitor is subjected to a heat treatment at 60 ° C. or more for 3 minutes or more in a discharged state, and then the inspection is performed. It has an effect that the reliability of the electrolytic capacitor can be further increased by heating in a discharged state.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a circuit diagram showing an outline of an electrolytic capacitor inspection apparatus according to one embodiment of the present invention. In the figure, PS1 is a power supply for supplying electric energy, C
1 is an inrush current supply capacitor for applying an inrush current to the test electrolytic capacitor Cs, C2 is a backup capacitor of the inrush current supply capacitor C1, R1 is a discharge resistor, R2 and R3 are charge resistors, and SW1 is a test resistor. Switch.

In the inspection apparatus for an electrolytic capacitor having such a circuit, a power supply PS for supplying electric energy
1 and backup capacitor C via charging resistor R3
The charge is stored in 2. Next, charge is stored in the inrush current supply capacitor C1 via the charging resistor R2.
In this state, when the test electrolytic capacitor Cs is connected to the terminals A and B and the switch SW1 is turned on, a current can flow from the inrush current supply capacitor C1 to the test electrolytic capacitor Cs at once through the discharge resistor R1. it can.

At this time, the charging resistor R2 is a constant (about 98 at charging time t = 4 · C1 · R1) at which the inrush current supply capacitor C1 can be fully charged during the time between tests.
% Charge) is preferred.

The inrush current supply capacitor C
If the capacity of the capacitor 1 is four times or more the electrolytic capacitor Cs, the voltage of the electrolytic capacitor Cs approaches the voltage of the in-rush current supply capacitor C1, so that the voltage fluctuation of the electrolytic capacitor Cs can be suppressed. it can.

Further, when the capacity of the backup capacitor C2 is four times or more the capacity of the inrush current supply capacitor C1, the voltage of the inrush current supply capacitor C1 approaches the voltage of the backup capacitor C2,
Voltage fluctuations of the inrush current supply capacitor C1 can be suppressed.

Next, a method of inspecting the test electrolytic capacitor Cs using the inspection apparatus will be described.

The stored charge of the inrush current supply capacitor C1 is transferred to terminals A and B by a test electrolytic capacitor Cs.
Is connected to turn on the switch SW1, the discharge resistance R
1, a current flows from the inrush current supply capacitor C1 to the test electrolytic capacitor Cs at a stretch. At this time, a change in the voltage or current of the sample electrolytic capacitor Cs is measured and inspected. FIG. 2 shows changes in voltage and current at that time. In the figure, the voltage of a non-defective product becomes saturated after rapid charging. Also, the change in the current rapidly attenuates after the inrush current flows.

On the other hand, the voltage of the defective product drops due to discharge in the test electrolytic capacitor Cs after rapid charging. The current rapidly attenuates after the inrush current flows, but the current value increases due to discharge in the test electrolytic capacitor Cs.

As described above, by inspecting the change in the voltage and the current, it is possible to determine a non-defective product or a defective product.

In the above-mentioned inspection method, if the test electrolytic capacitor Cs is subjected to a heat treatment at 60 ° C. or more for 3 minutes or more in a discharged state and then inspected, the anode of the test electrolytic capacitor Cs is heated in the discharged state. Since an appropriate voltage is uniformly applied to the foil and the cathode foil, a more reliable inspection can be performed.

[0025]

As described above, the inspection apparatus for an electrolytic capacitor of the present invention can test a large current at a stretch by arranging an inrush current supply capacitor even if the current capacity of a power supply for supplying electric energy is low. An inspection device that can discharge to an electrolytic capacitor.This inspection device detects in the initial inspection of the electrolytic capacitor a short circuit due to the cut-off part of the cutting burr of the anode foil and the cathode foil, which is rare depending on the use conditions. Thus, an electrolytic capacitor with improved quality can be obtained.

[Brief description of the drawings]

FIG. 1 is a circuit diagram schematically illustrating an inspection apparatus for an electrolytic capacitor according to an embodiment of the present invention.

FIG. 2 is a waveform chart showing changes in voltage and current by inspection of the electrolytic capacitor according to the embodiment.

FIG. 3 is a developed perspective view showing a capacitor element of a conventional electrolytic capacitor.

[Explanation of symbols]

 C1 Inrush current supply capacitor C2 Backup capacitor Cs Test electrolytic capacitor R1 Discharge resistor R2, R3 Charge resistor SW1 Switch PS1 Power supply for supplying electric energy

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2G036 AA22 BB02 CA12 5E082 AA07 AB04 AB09 BC36 BC38 GG04 KK04 MM24 MM35 MM38 PP01 PP05 PP06

Claims (6)

[Claims] 1. An inrush current supply capacitor disposed in parallel with a test electrolytic capacitor via a resistor, a power supply for charging the inrush current supply capacitor and a backup capacitor are provided, and a backup capacitor and an inrush current supply capacitor are provided. Inspection device for electrolytic capacitors with a charging resistor in series between them. 2. The capacity of the inrush current supply capacitor is at least four times the capacity of the test electrolytic capacitor.
An inspection device for an electrolytic capacitor according to item 1. 3. The electrolytic capacitor inspection device according to claim 1, wherein the capacity of the backup capacitor is at least four times the capacity of the inrush current supply capacitor. 4. The electrolytic capacitor according to claim 1, wherein an inrush current is applied to the test electrolytic capacitor up to a rated voltage or a surge voltage, and a change in voltage or current after charging is inspected. Method for inspecting electrolytic capacitors using the inspection apparatus of the present invention. 5. The test is performed by applying an inrush current of 30 A or more to a test electrolytic capacitor.
Inspection method of the electrolytic capacitor described in the above. 6. The test electrolytic capacitor is discharged at 60 ° C.
The inspection method for an electrolytic capacitor according to claim 4 or 5, wherein the inspection is performed after the heat treatment for three minutes or more.