JP6295412B2 - Capacitor manufacturing method and capacitor inspection apparatus - Google Patents

Description

  The present invention relates to a capacitor manufacturing method including an inspection process for inspecting the inrush resistance characteristics of a capacitor used in various electronic devices, electrical devices, industrial devices, automotive devices, and the like, and an inspection device for the capacitor.

  In recent years, electronic control of automobiles and the like has progressed, and along with this, battery performance has been remarkably improved, and those capable of supplying current exceeding 100 A instantaneously have become common. Various electronic components applied to power supply circuits such as batteries are required to be smaller and thinner with the progress of digitization of electronic devices and the like.

  For example, a capacitor that is an electronic component used in a smoothing circuit or a control circuit is required to have a small size, a large capacity, and a small equivalent series resistance (hereinafter abbreviated as ESR) in a high frequency region.

  In particular, the electrolytic capacitor is directly connected to a power supply circuit such as a battery via a switching element. When the switching element is turned on, a charging current flows directly from the battery to the electrolytic capacitor.

  Therefore, since the inrush current becomes larger as the electrolytic capacitor has a lower ESR, the inrush resistance property of each electrolytic capacitor is very important particularly in automotive electrical applications that require high reliability.

  FIG. 10 is a cross-sectional view showing a configuration of a conventional capacitor, and FIG. 11 is a configuration perspective view of a capacitor element.

  As shown in FIGS. 10 and 11, the conventional capacitor includes a capacitor element 52 which is a functional element, a pair of lead wires 51a and 51b each having one end connected to the capacitor element 52, and these lead wires. An outer body 55 is formed by sealing the capacitor element 52 together with a driving electrolyte (not shown) so that the other ends of 51a and 51b are led out to the outside.

  The exterior body 55 includes a bottomed cylindrical exterior case 53 containing a capacitor element 52 impregnated with a driving electrolyte and through holes 54a and 54b through which the lead wires 51a and 51b are inserted, respectively. A sealing body 54 is disposed in the opening of the case 53 and is sealed by compressing and deforming the drawing portion 53a provided on the outer peripheral surface of the outer case 53 to seal the opening of the outer case 53. The sealing body 54 uses rubber packing.

  Further, as shown in FIG. 11, the capacitor element 52 is made of an anode foil 52a in which a foil made of a valve metal such as aluminum is roughened by an etching process, and a dielectric layer of an anodic oxide film is formed on the surface thereof by a chemical conversion process. And a cathode foil 52b made of a valve metal such as aluminum are stacked and wound via a separator 52c.

  The capacitor produced in this way is designed to obtain a higher quality capacitor by performing a repair formation of the anode foil 52a by aging.

  Next, a description will be given of a destruction mechanism in the case where there is a defective portion in the conventional capacitor and an inrush current is applied thereto.

  FIG. 12 is a schematic cross-sectional view showing a state in the capacitor element when an inrush current is applied to a capacitor having a defect inside. As shown in FIG. 12, inside the capacitor element 52, there is an anode foil 52a made of a valve metal such as aluminum having a dielectric layer 61 of an anodic oxide film on the surface, and a conductive protrusion 62 which is a defective portion. The cathode foil 52b faces the separator 52c.

  First, in the stage (A), electrons 64 are supplied to the cathode foil 52 b by the battery 63, and the electrons 64 on the surface of the anode foil 52 a in contact with the dielectric layer 61 move to the battery 63 and contact the dielectric layer 61. Holes 65 are formed on the surface of the anode foil 52a.

  Next, in the stage (B), the electrons 64 in the cathode foil 52b are moved to the anode foil side 52a having the holes 65 by the Coulomb force via the conductive protrusion 62 having a resistance lower than that of the driving electrolyte. It is attracted and concentrated on the surface of the dielectric layer 61.

  And finally, in the stage of (C), when the potentials of the electrons 64 and the holes 65 concentrated by the holes 65 and the conductive protrusions 62 of the anode foil 52a exceed the withstand voltage of the dielectric layer 61, An avalanche occurs, a large current flows between the anode foil 52a and the cathode foil 52b, leading to dielectric breakdown (puncture).

  From such a mechanism, as the inrush current is larger, electrons are more likely to concentrate on the conductive protrusion 62 having a lower resistance than that of the driving electrolyte solution. Therefore, the frequency of occurrence of electron avalanche increases and dielectric breakdown tends to occur.

  FIG. 13 shows an inspection waveform diagram of the voltage and current of the capacitor in the inrush current resistance test. FIG. 13A is an inspection waveform diagram of the voltage and current in a non-defective capacitor, and FIG. The inspection waveform figure of the voltage and electric current in a good article is shown. In the waveform of the defective product in (B), reference numerals 71 and 73 denote cases where a large spark is generated due to voltage spark noise and current spark noise during capacitor charging. Reference numerals 72 and 74 denote voltage noise and current noise when a minute spark occurs during voltage application after capacitor charging.

  As described above, the time until the avalanche is generated in the capacitor element 52 is greatly influenced by the size of the protrusion and the formation state of the oxide film, but the early one is several μs, such as 71 and 73, which is slow. It has been experimentally found that avalanches occur after several tens of milliseconds after voltage saturation, as in 72 and 74.

  For example, Patent Documents 1 to 3 are known as prior art document information related to the present invention.

JP 2000-348990 A JP 2001-338851 A JP 2002-110485 A

  However, in the above-described conventional capacitor inspection process and device, the voltage / current waveform is inspected for several tens of milliseconds while the circuit for applying the inrush current for rapid charging to the capacitor is operated. The voltage spark noise and current spark noise due to the minute spark that is one thousandth of the inrush current of the current cannot be detected, or the minute voltage fluctuation and current fluctuation caused by the oxide film defect due to the spark cannot be detected in the inspection process There was a problem.

  Further, the connection resistance between the lead wire and the anode foil and the cathode foil is usually 1 mΩ or less, but may be 10 mΩ or more due to poor connection. Although this may lead to disconnection failure, the internal resistance of the finished product of the capacitor is usually 100 mΩ or more, so the connection resistance at the 10 mΩ level is within the error range, and there is a problem that direct measurement with an inspector is not possible. there were.

  In addition, if the capacitor to be inspected is short-circuited, the energy supplied from the inrush circuit to which the large-capacitance capacitor is connected in parallel will cause the capacitor to be inspected to puncture or ignite, and the electrolyte will be scattered during the inspection process. There was a problem that the production line was contaminated.

  Therefore, the present invention solves the problem in the inspection process for inspecting the inrush resistance characteristics of the conventional capacitor, and detects even a small spark in the inspection process with high sensitivity, and has not been in the conventional inspection process. An object of the present invention is to provide a highly reliable method of manufacturing a capacitor and an inspection device for the capacitor by detecting a connection abnormality between the connecting portion of the electrode foil and the electrode foil.

  In addition, even when a capacitor to be inspected is short-circuited, it is possible to suppress puncture and ignition, and it is an object of the present invention to provide a capacitor manufacturing method and a capacitor inspection device that improve productivity and safety. is there.

In order to achieve the above object, the present invention is a method of manufacturing a capacitor including an inspection step of inspecting the inrush resistance characteristics of a capacitor to be inspected,
The inspection process includes
(1) A first step of placing the discharge circuit in an activated state and discharging the capacitor to be inspected, and then bringing the discharge circuit into a stopped state;
(2) Next, during a predetermined time T1, the inrush circuit is activated, the inrush current is applied to the capacitor to be inspected to charge the capacitor, and the current flowing through the capacitor and / or A second step of stopping the inrush circuit after continuously measuring the voltage across the terminals of the capacitor continuously or intermittently;
(3) For a predetermined time T2 from the end of the second step to the end of the second step, the voltage holding circuit is activated to hold the voltage between the terminals of the capacitor to be inspected, and the capacitor A third step of stopping the voltage holding circuit after continuously or intermittently measuring the current flowing through the capacitor and / or the voltage between the terminals of the capacitor;
(4) Next, a fourth step of bringing the discharge circuit into an operating state, discharging the capacitor to be inspected, and then stopping the discharging circuit;
(5) Finally, the current and / or voltage measured in the second step and the current and / or voltage measured in the third step are respectively compared with predetermined reference values,
And a fifth step of determining whether the inrush current resistance characteristic of the capacitor to be inspected is good or bad.

  As described above, according to the present invention, an inrush current is rapidly applied to a capacitor to be inspected for a predetermined time and then continuously switched to low current measurement by a voltage holding circuit. Small voltage fluctuations and current rises can be detected. Further, if the connection resistance of the connection portion between the lead wire and the electrode member such as the electrode foil is higher than the reference non-defective product, the connection portion is defective due to thermal expansion or melting and can be detected.

  Further, since the inrush circuit is turned off except for the rapid charging of the capacitor, the capacitor can suppress puncture and ignition even when the capacitor to be inspected is short-circuited.

  As a result, by manufacturing capacitors using this inspection process, it is possible to determine the anti-inrush performance on-line with high accuracy in a short time, and it is not possible to continue applying a large current to defective products. Can be prevented from bursting.

1 is a circuit configuration diagram of an inrush current resistance test apparatus for capacitors according to Embodiment 1 of the present invention. Circuit switching timing chart according to the first embodiment of the present invention (A) Voltage / current inspection waveform diagram when the capacitor according to Embodiment 1 of the present invention is a non-defective product, (B) Voltage / current inspection waveform diagram when the capacitor according to Embodiment 1 of the present invention is a defective product The graph which shows the capacitor | condenser discharge time in the inrush-proof current test | inspection of the capacitor | condenser in Embodiment 1 of this invention The graph which shows the capacitor destruction time in the inrush current-proof test of the capacitor in Embodiment 1 of the present invention Timing chart of circuit switching in Embodiment 2 of the present invention Voltage / current inspection waveform diagram of capacitor in Embodiment 2 of the present invention Sectional drawing which showed the structure of the capacitor | condenser in Embodiment 3 of this invention FIG. 3 is an exploded perspective view of the capacitor element of the capacitor according to Embodiment 3 of the present invention. Sectional view showing the structure of a conventional capacitor Development perspective view of capacitor element of conventional capacitor Cross-sectional schematic diagram showing the state of the capacitor element when an inrush current is applied to a capacitor having a conventional defect (A) Voltage and current inspection waveform diagram for non-defective product of conventional capacitor, (B) Voltage and current inspection waveform diagram for defective product of conventional capacitor

(Embodiment 1)
A capacitor inrush current resistance test apparatus and test process according to Embodiment 1 of the present invention will be described below with reference to FIGS.

  FIG. 1 is a circuit configuration diagram of a capacitor inrush current resistance inspecting process according to Embodiment 1 of the present invention, FIG. 2 is a timing chart of circuit switching according to Embodiment 1 of the present invention, and FIG. FIG. 6 shows a voltage / current inspection waveform diagram when the capacitor according to the first embodiment is a non-defective product, and FIG. 5B shows a voltage / current inspection waveform diagram when the capacitor according to the first embodiment of the present invention is a defective product.

  In FIG. 1, 1 is a power supply, and 2 is a backup capacitor for maintaining an inrush current. An inrush current switching element 3 switches the inrush circuit (path) 21. Reference numerals 4 and 5 denote an inrush current measuring resistor and an inrush current measuring voltmeter of a measuring unit for measuring the inrush current. The resistance value of the inrush current measuring resistor 4 is preferably 1 mΩ to 1000 mΩ. A voltage holding circuit switching element 6 switches a voltage holding circuit (path) 22 that holds a voltage at a low current. Reference numerals 7 and 8 denote a low-current measuring resistor and a low-current measuring voltmeter of a measuring unit that measures voltage or current fluctuation, and the resistance value of the low-current measuring resistor 7 is preferably 10Ω to 1000Ω. When the inrush current measurement resistor 4 and the low current measurement resistor 7 are in a ratio of 1: 1000, the measurement range of the inrush current and the leakage current changes 1000 times, so that the leakage current can be measured with high sensitivity. Reference numeral 9 denotes a discharge circuit switching element for switching the discharge circuit (path) 23. Reference numeral 10 denotes a discharge resistance. Reference numeral 13 denotes an inspection target capacitor to be inspected for inrush current resistance, and 11 denotes a terminal voltage measurement voltmeter of the inspection target capacitor. 12 is an inrush current switching element 3, a voltage holding circuit switching element 6, a switch timing control for the discharge circuit switching element 9, an inrush current measuring voltmeter 5, a low current measuring voltmeter 8, an inspection This is a control / inspection unit that controls the measurement timing of the terminal voltage measurement voltmeter 11 of the target capacitor and determines the inspection result.

  The control / inspection unit 12 is composed of a PLC or the like, and can compare and determine inspection values by digitizing the ON / OFF control and voltage input of each circuit with an A / D converter.

  Next, the operation of the circuit will be described with reference to the timing chart of FIG. 2 and the circuit configuration diagram of FIG.

  First, the state before the inrush current resistance test of the capacitor to be inspected 13 is that the Tr3 which is the switching circuit 9 for the discharge circuit is valid until the start of the inspection, and the discharge circuit (path) 23 for discharging the capacitor to be inspected 13. Is working.

  Next, simultaneously with the start of inspection, the discharge circuit switching element 9 is disabled, and the discharge circuit (path) 23 is stopped.

  After the inspection is started, the inrush circuit (path) 21 for applying the inrush current to the inspection target capacitor 13 is activated by enabling the inrush current switching element 3 for a predetermined time T1. Thereby, the capacitor | condenser 13 to be tested is rapidly charged to the set voltage. In the meantime, the value of V2 which is the inrush current measurement voltmeter 5 is read, the peak value is converted into a current value, and stored as an inrush current value.

  Next, Tr2 which is the voltage holding circuit switching element 6 is activated and the voltage holding circuit (path) 22 is activated during time T1 in order to suppress the voltage change of the circuit switching. During the time T2, the voltage of the inspection target capacitor 13 is held at a low current, and the voltage (current) of V1 which is the terminal voltage measurement voltmeter 11 of the inspection target capacitor and V3 which is the low current measurement voltmeter 8 is measured. Measurement) Changes and values are monitored by the control / inspection unit 12.

  Finally, when the time T2 elapses, the voltage holding circuit switching element 6 (Tr2) is invalidated, the voltage holding circuit (path) 22 is stopped, and the discharge circuit switching element 9 (Tr3) is validated. A discharge circuit (path) 23 for discharging the target capacitor 13 is activated, and the inspection process is terminated.

  Next, with reference to FIG. 3, a process of determining a spark failure of the capacitor to be inspected 13 by the above series of operations will be described.

  Here, voltage fluctuations that occur when the inspection target capacitor 13 sparks are small when the inspection target capacitor 13 is a non-defective product and large when the inspection target capacitor 13 is a defective product. Value setting is required.

  FIG. 3A shows a voltage / current inspection waveform diagram when the inspection target capacitor 13 in the first embodiment of the present invention is a non-defective product, and FIG. 3B shows the inspection target capacitor in the first embodiment of the present invention. 13 shows a voltage / current inspection waveform diagram when 13 is a defective product.

  First, when the capacitor 13 to be inspected is a non-defective product, the inrush current is stable if the capacitor 13 to be inspected has the same product number. Therefore, the absolute value of the current value depends on whether or not the capacitor 13 to be inspected is sparked. Changes.

  Therefore, the pass / fail judgment of the inspection result is as follows. (1) When the inrush current (the value of the voltmeter 5 for measuring the inrush current in FIG. 1, that is, the V2 value) flows more or less than the reference, What is necessary is just to make NG determination, and this raises a detection level.

  Next, when the capacitor 13 to be inspected in (B) is a defective product, particularly when the inrush resistance is clearly insufficient, if a spark occurs during the application of the inrush current, a voltage drop of 31 occurs. 33 discharge currents flow.

  Therefore, the voltage drop 31 varies greatly depending on the capacity of the capacitor 13 to be inspected and the state of the spark, so that it is difficult to obtain a stable waveform. However, the pass / fail determination of the inspection result can be determined by the determination of (1) above. .

  In addition, when the capacitor 13 to be inspected is a defective product, when the inrush resistance performance is very low, a spark often occurs several tens of ms after the application of the inrush current. For this reason, in order to increase the detection capability, it is necessary to hold the voltage. When a spark is generated when a voltage is held at a high resistance (10 to 1000Ω) as in the present invention, a large voltage fluctuation 32 can be obtained, and therefore a minute current change 34 can be detected.

  Therefore, the pass / fail judgment of the inspection result is as follows: (2) V1 (value of the terminal voltage measurement voltmeter 11 of the capacitor to be inspected in FIG. 1) or V3 (low current measurement in FIG. When the voltage fluctuation of the value of the voltmeter 8 exceeds the fluctuation regulation value, an NG determination may be made, thereby increasing the detection level.

  Further, when sparking occurs inside the capacitor 13 to be inspected, the oxide foil on the surface of the electrode foil is lost, and a repair current 35 flows.

  Therefore, the pass / fail judgment of the inspection result is (3) When the value of V3 at the end of the time T2 exceeds the specified value, the NG determination is made to accurately determine the spark failure of the inspected capacitor 13. it can.

  When the capacitor 13 to be inspected is a non-defective product, a voltage fluctuation 36 occurs during the inspection process. This voltage fluctuation 36 is a small voltage fluctuation generated when the inrush circuit (path) 21 is stopped. is there. For this reason, it is necessary to set a fluctuation regulation value that can be distinguished from a large voltage fluctuation 32 due to spark when the capacitor 13 to be inspected is a defective product. The voltage fluctuation 36 can be reduced by switching the stop of the inrush circuit 21 and the operation timing of the voltage holding circuit 22 in an overlapping manner.

  By inspecting the capacitor to be inspected 13 using the inspection result pass / fail judgment method of (1), (2) and (3) above, the inrush resistance can be determined online accurately and in a short time, and defective products Since no large current is continuously applied to the capacitor, it is possible to suppress the burst of the capacitor in the inspection process. As a result, the quality of the capacitor can be improved, and productivity and safety can be improved.

  As shown in FIG. 4, the discharge phenomenon of the test target capacitor 13 after the application of the inrush current often occurs within 50 ms, and the voltage holding circuit is preferably operated for 50 ms or more.

  Further, as shown in FIG. 5, when the time for applying the inrush current to the inspection target capacitor 13 is set to 10 ms or less, the number of inspection target capacitors 13 leading to destruction (puncture) is extremely reduced.

(Embodiment 2)
Hereinafter, the inrush current resistance test apparatus and test method for capacitors according to the second embodiment will be described with reference to FIGS.

  In the second embodiment, the same circuit configuration as that of the first embodiment, that is, the circuit configuration shown in FIG. 1 is applied. The difference from the first embodiment is a switching timing chart in the circuit.

  FIG. 6 is a timing chart of the circuit according to the second embodiment of the present invention.

  Here, the operation of the circuit will be described with reference to the timing chart of FIG. 6 and the circuit configuration diagram of FIG.

  First, the state before the inrush current resistance test of the capacitor to be inspected 13 is that the Tr3 which is the switching circuit 9 for the discharge circuit is valid until the start of the inspection, and the discharge circuit (path) 23 for discharging the capacitor to be inspected 13. Is working.

  Next, simultaneously with the start of inspection, the discharge circuit switching element 9 is disabled, and the discharge circuit (path) 23 is stopped.

  Then, after the start of the inspection, the inrush current switching element 3 is activated for the time T4, and the inrush circuit (path) 21 for applying the inrush current to the inspection target capacitor 13 is activated. Thereby, the capacitor | condenser 13 to be tested is rapidly charged to the set voltage. In the meantime, the value of V2 which is the inrush current measurement voltmeter 5 is read, the peak value is converted into a current value, and stored as an inrush current value.

  Thereafter, during time T5, Tr1 that is the switching element 3 for the inrush current is disabled, the inrush circuit (path) 21 is stopped, Tr3 that is the switching element 9 for the discharge circuit is enabled, and the inspected capacitor 13 The discharge circuit (path) 23 for discharging the is activated.

  Next, a series of operations in the inrush circuit (path) 21 and the subsequent discharge circuit (path) 23 are repeated a plurality of times.

  Thereafter, during time T4, the inrush current switching element 3 is enabled, and the inrush circuit (path) 21 for applying the inrush current to the test target capacitor 13 is activated. Thereby, the capacitor | condenser 13 to be tested is rapidly charged to the set voltage. In the meantime, the value of V2 which is the inrush current measurement voltmeter 5 is read, the peak value is converted into a current value, and stored as an inrush current value.

  Next, before the Tr1 that is the inrush current switching element 3 is disabled and the inrush circuit (path) 21 is switched from the operation to the stop, the Tr2 that is the voltage holding circuit switching element 6 is enabled and the voltage is held. The circuit (path) 22 is activated. Thereby, the voltage fluctuation at the time of circuit switching can be reduced.

  After that, the voltage of the inspection target capacitor 13 is continuously held at a low current for a time T6, and the terminal voltage measurement voltmeter 11 of the inspection target capacitor and the low current measurement voltmeter 8 of V3 are maintained. Voltage and current fluctuations and values are monitored by the control / inspection unit 12.

  Finally, when the time T6 has elapsed, the voltage holding circuit switching element 6 (Tr2) is disabled, the voltage holding circuit (path) 22 is stopped, and the discharge circuit switching element 9 (Tr3) is enabled to perform inspection. A discharge circuit (path) 23 for discharging the target capacitor 13 is activated, and the inspection process is terminated.

  In order to efficiently perform this inspection method, it is preferable to set the discharge resistance 10 in FIG. 1 as small as 10 mΩ to 1000 mΩ.

Here, a voltage / current test waveform diagram of the capacitor according to the second embodiment of the present invention is shown in FIG. As shown in FIG. 7, the inrush circuit (path) 21 is activated during a time T4, and the discharge circuit (path) 23 is activated during a time T5. The large current is continuously applied. At this time, if the connection resistance of the connection portion between the lead wire and the electrode member such as the electrode foil is higher than the reference non-defective product inside the capacitor 13 to be inspected, the connection portion has a problem due to thermal expansion or melting. Come on. This is because, according to the formula E = I ² R, for example, when the resistance value is 10 times, the heat generation is also 10 times.

  As a result, the capacitor 13 to be inspected is likely to be short-circuited or instantaneously disconnected. Therefore, after the inrush current has been intermittently applied multiple times, it has not been possible to inspect conventionally by an inspection method that immediately detects a highly sensitive current fluctuation. Abnormalities in the connection can be detected and high quality capacitors can be provided.

(Embodiment 3)
A capacitor according to Embodiment 3 of the present invention will be described with reference to FIGS.

  FIG. 8 is a cross-sectional view showing the configuration of the capacitor according to Embodiment 3 of the present invention, and FIG. 9 is an exploded perspective view of the capacitor element of the capacitor.

  8 and 9, a foil made of a valve metal such as aluminum is roughened by an etching process, and an anode foil 42a formed by a chemical conversion treatment on the surface of the foil is made of a valve metal such as aluminum. Capacitor element 42 is configured by connecting lead wires 41a and 41b to cathode foil 42b and winding them together with separator 42c.

  The capacitor element 42 is impregnated with a driving electrolyte solution (not shown), and then stored in a bottomed cylindrical metal case 43 made of aluminum or the like, and the opening of the metal case is sealed with a sealing body 44.

  The sealing body 44 may be made of a resin material such as an epoxy resin in addition to a rubber material such as EPT or IIR.

  In addition, the electrode which comprises the capacitor | condenser element 42 may be the structure which laminates | stacks several electrode foil other than winding electrode foil.

  As the separator 42c, a nonwoven fabric containing cellulose, craft, polyethylene terephthalate, polybutylene terephthalate, polyphenylene sulfide, nylon, aromatic polyamide, polyimide, polyamideimide, polyetherimide, rayon, glassy material, or the like can be used.

  The driving electrolyte is configured to dissolve a solute in a solvent. Examples of the solvent material include γ-butyrolactone, ethylene glycol, sulfolane and the like. Solute materials include inorganic acid ammonium salts, inorganic acid amine salts, inorganic acid alkyl-substituted amidine salts or quaternized products thereof, organic acid ammonium salts, organic acid amine salts, organic acid alkyl-substituted amidine salts or quaternized products thereof. Etc.

  The driving electrolyte solution may appropriately contain additives for the purpose of gas absorption, withstand voltage stabilization, pH adjustment, oxidation prevention, and the like.

  Thereafter, the capacitor is subjected to an inrush current resistance test according to the circuit configuration shown in the first or second embodiment of the present invention, and a non-defective product is selected based on the pass / fail judgment of the test result.

  As described above, as a result of performing the inspection apparatus using the capacitor according to the first or second embodiment of the present invention using the capacitor according to the third embodiment of the present invention, the anti-lash performance of the capacitor can be accurately and quickly online. In addition to being able to discriminate, a large current is not continuously applied to the defective product, and the driving electrolyte is not scattered in the inspection process. In addition, after the inrush current is intermittently applied a plurality of times, an abnormality in the connection portion that could not be inspected in the past can be detected immediately by an inspection process for detecting current fluctuation with high sensitivity. As a result, the quality of the capacitor can be improved, and productivity and safety can be improved.

  Capacitors manufactured using the inspection process for inspecting the inrush current resistance characteristics of the present invention are suitable for switching applications directly connected to batteries and household outlets, and are characterized by being resistant to inrush currents caused by external noise such as lightning surges. It is useful in automotive electrical equipment, FA control circuits, and ballast circuits for lighting equipment, which are frequently turned on and off and require high reliability over a long period of time.

DESCRIPTION OF SYMBOLS 1 Power supply 2 Backup capacitor 3 Inrush current switching element 4 Inrush current measurement resistance 5 Inrush current measurement voltmeter 6 Voltage holding circuit switching element 7 Low current measurement resistance 8 Low current measurement voltmeter 9 Discharge Switching element for circuit 10 Discharge resistance 11 Voltmeter for measuring terminal voltage of capacitor to be inspected 12 Control / inspection unit 13 Capacitor to be inspected 21 Inrush circuit (path)
22 Voltage holding circuit (path)
23 Discharge circuit (path)

Claims (7)

Inspection comprising: a discharge circuit for discharging a capacitor to be inspected; an inrush circuit for charging the capacitor by applying an inrush current to the capacitor to be inspected; and a voltage holding circuit for holding a voltage between terminals of the capacitor to be inspected Using the device,
A method of manufacturing a capacitor including an inspection step of inspecting the inrush resistance characteristics of the capacitor to be inspected,
The inspection step includes (1) a first step of bringing the discharge circuit into an operating state, discharging the inspection target capacitor, and then stopping the discharge circuit;
(2) Next, during a predetermined time T1, the inrush circuit is activated, the inrush current is applied to the capacitor to be inspected to charge the capacitor, and the current flowing through the capacitor and / or A second step of stopping the inrush circuit after continuously measuring the voltage across the terminals of the capacitor continuously or intermittently;
(3) For a predetermined time T2 from the end of the second step to the end of the second step, the voltage holding circuit is activated to hold the voltage between the terminals of the capacitor to be inspected, and the capacitor A third step of stopping the voltage holding circuit after continuously or intermittently measuring the current flowing through the capacitor and / or the voltage between the terminals of the capacitor;
(4) Next, a fourth step of bringing the discharge circuit into an operating state, discharging the capacitor to be inspected, and then stopping the discharging circuit;
(5) Finally, the current and / or voltage measured in the second step and the current and / or voltage measured in the third step are respectively compared with a predetermined reference value, and the capacitor to be inspected And a fifth step of determining whether the inrush current resistance characteristics of the capacitor are good or bad.   The maximum value of the current measured in the second step is compared with the predetermined reference value in the fifth step to determine whether the inrush current resistance characteristics of the capacitor to be inspected are good or bad. Of manufacturing the capacitor.   The minimum value of the voltage measured in the third step is compared with the predetermined reference value in the fifth step to determine whether the inrush current resistance characteristic of the capacitor to be inspected is good or bad. A method for producing a capacitor as described in 1. above.   4. The capacitor manufacturing method according to claim 1, wherein the predetermined time T1 is 10 ms or less and the predetermined time T2 is 50 ms or more.   5. The method of manufacturing a capacitor according to claim 1, wherein after returning to the first step after the second step, the process proceeds to the third step after repeating a predetermined finite number of times. A discharge circuit for discharging the capacitor to be inspected;
An inrush circuit for charging the capacitor by applying an inrush current to the capacitor to be inspected;
A voltage holding circuit for holding a voltage between terminals of the capacitor to be inspected;
A first current measuring circuit capable of measuring a current flowing through the inspection target capacitor during operation of the inrush circuit;
A voltage measuring circuit capable of measuring a voltage between terminals of the capacitor to be inspected during the operation of the inrush circuit and the voltage holding circuit;
A control circuit for controlling the operation timing of the discharge circuit, the inrush circuit and the voltage holding circuit;
The current measured by the first current measuring circuit during the operation of the inrush circuit and the voltage measured by the voltage measuring circuit during the operation of the voltage holding circuit are respectively compared with a predetermined reference value, and the inspection object A capacitor inspection device comprising: a determination circuit configured to determine whether or not the inrush current resistance characteristics of the capacitor are good. A second current measuring circuit capable of measuring a current flowing through the test target capacitor during operation of the voltage holding circuit;
The determination circuit includes a voltage measured by the voltage measurement circuit during operation of the inrush circuit and / or a voltage measured by the second current measurement circuit during operation of the voltage holding circuit, respectively, as a predetermined reference value. The capacitor inspection device according to claim 6, which can also perform a pass / fail determination of the inrush current resistance characteristics of the capacitor to be inspected in comparison.

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