JP4391603B2 - Electrolytic capacitor aging device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electrolytic capacitor aging apparatus, and more particularly, to an apparatus for aging an electrolytic capacitor via a resistance element having a positive resistance temperature coefficient, for a buffer connected in parallel with a series circuit including the electrolytic capacitor and the resistive element. The present invention relates to a technique for increasing the degree of destruction by temporarily passing a large current through an electrolytic capacitor that has undergone short-circuit breakdown when the electrolytic capacitor to be aged breaks due to a short-circuit due to electric charge stored in the capacitor.
[0002]
[Prior art]
In general, an electrolytic capacitor is configured by interposing an electrolyte between an anode electrode and a cathode electrode having an oxide film such as a metal oxide formed on the surface thereof. For example, in a foil-type electrolytic capacitor, the surface of a metal foil such as aluminum constituting the anode electrode is oxidized to form a metal oxide film of aluminum oxide, and this is opposed to the cathode electrode of the metal foil such as aluminum through an electrolyte solution. I am letting.
[0003]
In such an electrolytic capacitor manufacturing process, a part of the metal oxide film may be damaged. This damage to the metal oxide film degrades the performance of the electrolytic capacitor or renders it unusable. Therefore, after the electrolytic capacitor is assembled, aging is performed to re-form the metal oxide film of the electrolytic capacitor and repair the metal oxide film. This aging is performed by applying a regenerated voltage determined by characteristics such as the capacity and breakdown voltage of the electrolytic capacitor to both electrodes of the electrolytic capacitor for an appropriate time.
[0004]
Conventionally, this re-forming process is carried out by using an aging device having a circuit configuration as shown in FIG. 4 for a high-voltage small product such as an electrolytic capacitor for a strobe used in a disposable camera or the like. Power electrolytic capacitors (Ca _{1 to} Ca ₁₂ ) are connected in parallel. During aging, an electrolytic capacitor having an internal defect may cause an internal puncture (short circuit occurs in a minute part and gas is abnormally generated), thereby causing a short circuit breakdown. In the aging apparatus as shown in FIG. 4, when an internal defect occurs in one of the 12 electrolytic capacitors, for example, Ca ₁ and a short circuit breaks, the other 11 electrolytic capacitors Ca _{2 to} Ca ₁₂ are stored. The collected electric charge concentrates on Ca ₁ and flows. Through experiments, it has been confirmed that an electrolytic capacitor with a short break at a minute portion can completely open the safety valve with the discharge current of the remaining electrolytic capacitor if the number of electrolytic capacitors connected in parallel is nine or more. ing. Therefore, if the number of electrolytic capacitors connected in parallel as shown in FIG. 4 is 12 or more, the safety valve can be completely opened more reliably. The electrolytic capacitor Ca _{1 that} has been short-circuited is completely destroyed, and the safety valve of the electrolytic capacitor is completely opened. Since the punctured electrolytic capacitor is likely to remain in a short state even when the safety valve is opened, the power supply capacity is not supplied to the electrolytic capacitor that is not short-circuited due to the short circuit, and the electrolytic capacitors Ca _{2 to} Ca ₁₂ are reconnected. Insufficient formation will occur. For this reason, whenever a short-circuit failure of the electrolytic capacitor occurs during aging, the electrolytic capacitor that has undergone the short-circuit failure must be manually removed by judging from the appearance such as the opening of the safety valve. Since it was necessary to remove the electrolytic capacitor during the aging process, the automation of the re-forming process was not easy and the work efficiency was also poor.
[0005]
In a recent re-forming process, a circuit configuration as shown in FIG. 5 is used in which a PTC thermistor (Pb _{1 to} Pb ₁₂ ) is connected in series to each electrolytic capacitor (Cb _{1 to} Cb ₁₂ ) to be aged for automation. An aging apparatus having the following has been used. When automating the re-forming process, it is difficult to immediately remove the broken electrolytic capacitor even if a short break occurs during aging. It is necessary to limit the power supply capacity to an electrolytic capacitor that is not short-circuit broken. For this reason, a current limiter such as a PTC thermistor is connected to each electrolytic capacitor, and when a current exceeding a certain level flows, the PTC thermistor generates heat, increases its resistance value, and acts to limit the current. Even if the electrolytic capacitor is short-circuited during aging and the current increases due to the short circuit, the current value is automatically limited within a certain frame by a PTC thermistor, etc., so that sufficient voltage and current are supplied to other electrolytic capacitors. Therefore, there will be no shortage of reformation. As a result, even if a short-circuit breakdown of the electrolytic capacitor occurs during aging, it is not necessary to immediately remove the broken electrolytic capacitor, which makes it easy to automate the re-forming process.
[0006]
[Problems to be solved by the invention]
Some electrolytic capacitors that have been short-circuited during aging are temporarily repaired by subsequent aging if they are broken, and show electrical characteristics equivalent to non-defective products. There are also things. For this reason, electrolytic capacitors that have broken short during aging need to be sorted and removed after aging, but are difficult to sort by electrical characteristics for temporary repair. Therefore, for example, by using the change in appearance caused by short breakage such as the aluminum case of the electrolytic capacitor bulging due to the occurrence of gas abnormality or the safety valve of the electrolytic capacitor opening, it must be visually removed after aging is completed. Don't be. In order to facilitate the selective removal by visual observation, it is desirable that the change in appearance of the electrolytic capacitor that has undergone short-circuit breakdown is large.
[0007]
However, in the aging device having the circuit configuration as shown in FIG. 5, since each PTC thermistor is connected to each electrolytic capacitor, the degree of breakdown of the electrolytic capacitor that has been short-circuited during aging is increased, or the safety valve The energy for opening the valve is limited to the supply from the power source. In addition to the PTC thermistor, an external charging resistor R is connected between the power supply and the electrolytic capacitor. Therefore, the supply of power from the power supply alone increases the degree of destruction of the electrolytic capacitor that is short-circuited during aging. It was difficult to pass a sufficient current to open the safety valve. Therefore, many electrolytic capacitors that have undergone short circuit breakdown during aging have a slight change in appearance. For this reason, a skilled worker is required for the visual selection and removal process of the electrolytic capacitor that has been short-circuited, and the accuracy of the selection is also a problem. Another problem is that a great deal of labor and costs are consumed.
[0008]
An object of the present invention is to provide an electrolytic capacitor aging device that can easily and accurately select electrolytic capacitors after completion of aging in view of the above-described problems in the prior art.
[0009]
Another object of the present invention is to increase the degree of destruction of an electrolytic capacitor partially destroyed during aging, thereby enabling easy and reliable selection after the end of aging, and It is an object of the present invention to provide an electrolytic capacitor aging device that automatically and accurately suppresses excessive concentration of current so as not to cause insufficient reformation of an electrolytic capacitor that has not been destroyed.
[0010]
[Means for Solving the Problems]
According to the present invention includes a plurality of resistance elements having a positive temperature coefficient of resistance of each of a plurality of electrolytic capacitors to be aged are connected in series, a power source for applying a voltage to the plurality of electrolytic capacitors to be the aging, a charging resistor, a aging device of the electrolytic capacitor for applying a voltage to the plurality of electrolytic capacitors to be the aging than the power supply through a plurality of resistor elements, the said resistive element and a plurality of electrolytic capacitors to be the aging A buffer capacitor connected in parallel with the series circuit, and configured to cause a discharge current of the buffer capacitor to flow through the electrolytic capacitor to be aged, which is short-circuited during aging. With such a configuration, when a short circuit breakage occurs in the electrolytic capacitor to be aged during aging, a large current can be temporarily and efficiently passed from the buffer capacitor to the electrolytic capacitor subjected to the short circuit breakage. For this reason, in the electrolytic capacitor that has undergone short-circuit breakdown, the degree of breakdown can be increased accurately, and changes in appearance and electrical characteristics can be accurately increased. Sorting and removing can be performed easily and reliably with high accuracy.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an aging device for an electrolytic capacitor according to the present invention will be described with reference to the drawings.
[0012]
FIG. 1 shows a schematic circuit of an aging device for electrolytic capacitors according to an embodiment of the present invention.
[0013]
In FIG. 1, for example, n electrolytic capacitors C _{1 to} C _n to be aged are mounted on the jig A ₁ , and PTC thermistors P _{1 to} P _n are connected in series to the electrolytic capacitors to be aged. Yes. The series connection with the electrolytic capacitors C _{1 to} C _n is not limited to the PTC thermistor, and any element having a positive resistance temperature coefficient whose electrical resistance increases as the temperature rises may be used. N series circuits of such an electrolytic capacitor and a PTC thermistor are connected in parallel between terminals a and b. The number n of series circuits of electrolytic capacitors and PTC thermistors connected in parallel is arbitrarily set in consideration of the type of electrolytic capacitor to be aged and the size of the power source.
[0014]
Changeover switch 2, depending on the stage of aging, and is configured to connect the terminal a of the jig A ₁ sequentially to the terminal d ₁ to d _m. Changeover switch 3 selects the terminal b of the jig _{A 1,} and is configured to connect sequentially to the terminal _e 1 to e _m. This example, the terminals a and b of the jig _{A 1} and the sliding electrode, the sliding electrode and the sliding contact with the terminal electrode terminals _d 1 to d _m a terminal a, a terminal _e 1 to e _m of the terminal b a sliding electrode and the sliding contact with the terminal electrodes, and placing the jig a ₁ such as a conveyor belt was slowly moved at a constant speed, terminal d ₁ sliding electrode of the terminals a and b to d _m and e ₁ to e the _m terminal electrodes and time of sliding contact by adjusting the length of the terminal electrodes, configured to terminals a and b are sequentially connected one by an arbitrary time to the terminal d ₁ to d _m and e ₁ to e _m Is done.
[0015]
Each terminal _d 1 to d _m via a resistor _R 1 to R _m are connected to the positive potential side of the DC power source 1. Both terminal e ₁ to e _m is connected to the negative potential side of the DC power source 1. Each of the resistance value of the number m and resistor _R 1 to R _m of the terminal _d 1 to d _m and the resistor _R 1 to R _m is in consideration of the rising characteristics and aging conditions of the terminal voltage of the electrolytic capacitor to be aged Set arbitrarily. It is preferable magnitude of the resistance is _{R 1 ≧ R 2 ≧ ··· ≧} R m. For example, R ₁ = 5 kΩ and R _m = 22Ω. Furthermore, also connected to the negative potential side of the DC power source 1 each terminal _d 1 to d _m via the capacitor _Cp 1 ~ CP _m buffer.
[0016]
FIG. 2 is a diagram showing the temperature dependence of the electrical resistance of the PTC thermistor used in this embodiment. As the temperature rises, the electrical resistance increases.
[0017]
Next, the operation of the electrolytic capacitor aging apparatus having such a configuration will be described.
[0018]
First, the changeover switch 2 terminal d ₁ the terminal a, to the changeover switch 3 to connect the terminal b to the terminal e _1, to obtain a voltage necessary for reformation electrolytic capacitor C ₁ -C _n, DC A DC voltage is applied between the terminals a and b by the power source 1 (voltage V ₁ ). Thereby, a current flows through each of the PTC thermistors P _{1 to} P _n and the electrolytic capacitors C _{1 to} C _n are charged. However, since each PTC thermistor P _{1 to} P _n has a positive resistance temperature coefficient as shown in FIG. 4, when the energization current increases, the temperature rises and the electrical resistance value increases, thereby suppressing the current. It works like this. Thereby, since the flowing current can be suppressed within a certain frame, stable aging can be performed while suppressing the heat generation of the electrolytic capacitors C _{1 to} C _n .
[0019]
In order to suppress the heat generation of the electrolytic capacitor, it is preferable to suppress the initial aging voltage and current and increase the voltage and current stepwise. Jig _{A 1} slowly moves at a constant speed rests like a conveyor belt, the terminal a is sequentially terminals _{d 1,} d 2, · · ·, is switched to connect the _{d m,} terminal b is sequentially terminal _{e 1} , _e 2, ···, so switched as to connect with _{e m,} the resistor connected in the aging circuit _{R 1, R 2, ···,} sequentially switched to _{R m.} When the magnitude of the resistance is R ₁ ≧ R ₂ ≧... ≧ R _m , the aging voltage and current are gradually increased by switching the resistance connected in the aging circuit to one having a smaller resistance value. To rise. In some cases, the output voltage of the DC power supply 1 may be switched in stages.
[0020]
The voltage between the terminals of the electrolytic capacitors C _{1 to} C _n reaches the voltage V ₁ of the DC power supply 1 after a certain period of time, and is maintained for an appropriate time, so that the electrolytic capacitors C _{1 to} C _n are re-formed. On the other hand, during the aging of the electrolytic capacitor _C 1 -C _n, the DC voltage of the DC power source 1 is also applied to the capacitor _Cp 1 ~ CP _m buffer. The capacitor Cp ₁ ~ CP _m buffer is charged, the terminal voltage is almost reached to the voltage V ₁ of the DC power source 1 and maintained. Capacitor Cp ₁ ~ CP _m buffer during the aging step, it is preferable that all times between the terminal voltage is charged in approximately V _1.
[0021]
During aging of the electrolytic capacitors C _{1 to} C _n , for example, when the terminal a is connected to the terminal d ₂ and the terminal b is connected to the terminal e ₂ , _one of the electrolytic capacitors C _{1 to} C _n , for example, the electrolytic capacitor C _Suppose that a short break occurs at ₁ . In the electrolytic capacitor C ₁ At this time, also caused a change in appearance such as gas abnormal occurrence to swell the aluminum case for example internally. By utilizing a change on the appearance, in the sorting inspection process by visually after aging can be removed electrolytic capacitor C _1. However, if the short disruption occurred during aging in the electrolytic capacitor C ₁ is small, the change in appearance is also small, it is difficult to get rid accurately electrolytic capacitor C ₁ in sorting inspection process. Screened to accurately remove the electrolytic capacitor C ₁ is in the inspection process, and disrupted allowed or completely increase the degree of destruction of the electrolytic capacitor C _1, such as to completely open the safety valve of the electrolytic capacitor, the change in appearance Should be increased. Further, if the degree of destruction is increased, it will not be temporarily repaired thereafter, and it can be removed as a defective electrical characteristic.
[0022]
If the short breakdown occurs in the electrolytic capacitor C _1, although the charge stored in the electrolytic capacitor C ₂ -C _n during aging is going flow into the electrolytic capacitor C _1, the PTC thermistor through two as resistance component Therefore, not a large current as to sufficiently increase the degree of destruction of the electrolytic capacitor C _1. The direct current power source 1 also acts to pass a current through the electrolytic capacitor C _1. However, since the resistor R ₂ is also added as a resistance component in addition to the PTC thermistor P ₁ , it is large enough to sufficiently increase the degree of destruction of the electrolytic capacitor C _1. It is difficult to pass a current from the DC power supply 1.
[0023]
In the aging device of the present embodiment, a buffer capacitor Cp ₂ is connected in parallel with a series circuit of electrolytic capacitors C _{1 to} C _n and PTC thermistors P _{1 to} P _n . The charge stored in the charged buffer capacitor Cp ₂ tends to flow into the electrolytic capacitor C ₁ via only _one PTC thermistor P ₁ . The resistive component is only one PTC thermistors P _1, and the current source is the charge stored in the capacitor, further, the PTC thermistor P ₁ is heated by the current increases, current limiting resistor is increased There is a time delay from the start of current increase. Therefore, a large current can be passed to the electrolytic capacitor C ₁ by a buffer capacitor Cp ₂ instantaneously and efficiently. If the capacitance of the buffer capacitor Cp ₂ is sufficiently large, the current flowing from the buffer capacitor Cp ₂ to the electrolytic capacitor C ₁ can be sufficiently increased, and the degree of destruction of the electrolytic capacitor C ₁ is increased to change the appearance. Can be made large enough.
[0024]
In the conventional aging apparatus as shown in FIG. 4, in order to flow a discharge current sufficient to completely open the safety valve to the short-circuited electrolytic capacitor, the number of electrolytic capacitors connected in parallel is preferably 9 or more, More preferably, 12 or more were necessary. In the aging device of the present embodiment Correspondingly, each of the capacitors Cp ₁ ~ CP _m buffer, the capacitance per one of the electrolytic capacitor C ₁ -C _n be aged at least about 8 times or more, Preferably, it has a capacitance of at least about 11 times. Furthermore, in the aging device of the present embodiment, the resistance component for one PTC thermistor is interposed in the path of the discharge current of the buffer capacitor. Therefore, depending on the characteristics of the PTC thermistors P _{1 to} P _n , It is preferable to use a larger capacitance. As a result, the discharge current of the buffer capacitor can be made large enough to increase the degree of breakdown of the short-circuited electrolytic capacitor and increase the change in appearance. Further, each of the capacitors _Cp 1 ~ CP _m buffer preferably has a high withstand voltage than the aging voltage _{V 1.} As a result, the buffer capacitor does not deteriorate during aging. For example, when aging electrolytic capacitors C _{1 to} C _n having a capacitance of 100 μF with the applied voltage of the DC power supply 1 being 350 V, a buffer capacitor of 400 WV-1200 μF, for example, an electrolytic capacitor may be used.
[0025]
FIG. 3 shows the time change of the current flowing through the PTC thermistor P ₁ after the electrolytic capacitor C ₁ is short-circuit broken during aging. When the electrolytic capacitor C ₁ is broken short, the current flowing through the PTC thermistor P ₁ due discharge current of the capacitor buffer rapidly increased (i.e. a large current flows into the electrolytic capacitor C _1), the degree of destruction of the electrolytic capacitor C ₁ Increases and the change in appearance also increases. Since the PTC thermistor P ₁ generates heat and the resistance value increases with time, the current flowing through the PTC thermistor P ₁ (that is, the current flowing into the electrolytic capacitor C ₁ ) starts to decrease and is limited to a certain range. Become. For this reason, even if the electrolytic capacitor C ₁ is destroyed short, concentration of current to the electrolytic capacitor C ₁ is will not last long. Therefore, the electrolytic capacitors C _{2 to} C _n that are not destroyed are sufficiently supplied with voltage and current from the DC power source 1 and do not become insufficiently reformed.
[0026]
By moving a plurality of jigs having the same configuration as the jig A ₁ continuously put like a conveyor belt, can also be carried out in a short time in succession one after another aging of a number of electrolytic capacitors. Thus even in continuous aged using a plurality of jig, the aging device of the present embodiment is applied to the capacitor Cp ₁ ~ CP _m interphase always buffers the DC voltage V ₁ is the aging process of the DC power source 1 because, if Shojire a short disruption in the electrolytic capacitor to be aged in the aging, a large current and instantaneous efficiently the electrolytic capacitor is shorted destroyed from either constantly charged capacitor Cp ₁ buffer are ~ CP _m The degree of destruction of the electrolytic capacitor that has temporarily flowed in and short-circuited can be accurately increased, and the change in appearance can also be accurately increased.
[0027]
Although specific embodiments have been described, the present invention is aging by the electric charge stored in the buffer capacitor connected in parallel with the series circuit composed of the electrolytic capacitor to be aged and the resistance element having a positive resistance temperature coefficient. However, the present invention is not limited to the above-described embodiment as long as a current is passed through the electrolytic capacitor to be aged that is short-circuited.
[0028]
【The invention's effect】
As described above, when an electrolytic capacitor to be aged breaks short during aging, a large current is passed through the electrolytic capacitor that has been short-circuited by a buffer capacitor to increase the degree of breakdown. It is possible to increase the change in the appearance of the electrolytic capacitor that has undergone short circuit breakage, such as increasing the swelling of the electrolytic capacitor or completely opening the electrolytic capacitor safety valve.
[0029]
In addition, after a large current flows and the degree of breakdown increases, the current flowing through the short-circuited electrolytic capacitor is automatically limited within a certain range by a PTC thermistor, etc. There is no shortage. For this reason, it is possible to easily and accurately perform the sorting of the electrolytic capacitor that has been short-circuited during the aging in the sorting inspection process subsequent to the aging process. Furthermore, the selection does not require an expert, the time required for the selection is shortened, and the manufacturing cost can be improved.
[0030]
In addition, if the degree of destruction is increased in an electrolytic capacitor in which a minute part is short-circuited during aging, it will not be temporarily repaired by subsequent aging. Even if it is not, it can be removed as a defect in electrical characteristics. If the electrolytic capacitor safety valve is fully open, it can be automatically removed during the aging process.
[Brief description of the drawings]
1 is a schematic circuit diagram of an electrolytic capacitor aging device according to an embodiment of the present invention;
FIG. 2 is a graph showing temperature dependence of electrical resistance of a PTC thermistor used in an embodiment of the present invention.
FIG. 3 is a graph showing a change with time of a current flowing through a PTC thermistor after an electrolytic capacitor is short-circuit broken during aging.
FIG. 4 is a schematic circuit diagram of a conventional electrolytic capacitor aging device.
FIG. 5 is a schematic circuit diagram of a conventional electrolytic capacitor aging device using a PTC thermistor as a current limiter.
[Explanation of symbols]
1 DC power source 2 changeover switch _{A 1} jig _{C 1, C 2, ......,} C n, Ca 1, Ca 2, ......, Ca 12, Cb 1, Cb 2, ......, should _{Cb 12} Aging electrolytic capacitor _{Cp 1, Cp 2, ......,} Cp m buffer capacitor _{P 1, P 2, ......,} P n, Pb 1, Pb 2, ......, Pb 12 PTC thermistor _{R, R 1, R 2,} ... ..., _{R m} resistance

Claims (1)

Comprising a plurality of resistance elements having a positive temperature coefficient of resistance of each of a plurality of electrolytic capacitors to be aged are connected in series, a power source for applying a voltage to the plurality of electrolytic capacitors to be the aging, a charging resistor, said plurality An aging device for an electrolytic capacitor that applies a voltage to the plurality of electrolytic capacitors to be aged from the power source through the resistance element of
A buffer capacitor connected in parallel with a series circuit composed of the plurality of electrolytic capacitors to be aged and the resistance element is provided, and a discharge current of the buffer capacitor is allowed to flow through the electrolytic capacitor to be aged that has been short-circuited during aging. Electrolytic capacitor aging device characterized by the above.

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