JP2005085778A - Process for manufacturing aluminium electrolytic capacitor, and connection resistance inspecting device employing it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem wherein the measurements of the connection resistance of a lead wire caulked to an electrode foil have significant variations and reliability thereof is low, and to provide a process for manufacturing a high-reliability aluminium electrolytic capacitor and a connection resistance inspection device. <P>SOLUTION: When the central lead wire 2 of a set of three lead wires 2 out of a plurality of lead wires 2 connected with a stripe electrode foil 1 at a constant interval is inspected, a constant voltage is applied between that lead wire 2 and one adjacent lead wire 2a, and a current flowing between the lead wires is measured. A voltage, generated between that lead wire 2 and the other adjacent lead wire 2b, is measured, and the resistance is determined from that voltage value and current value thus inspecting connection resistance. According to such a connection resistance inspection method, connection resistance between the lead wire 2 and the electrode foil 1 can be measured with high accuracy, and both the reliability and the yield can be enhanced simultaneously. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention provides an aluminum electrolytic capacitor manufacturing method for inspecting a connection state of a lead lead caulked to an electrode foil, and a connection resistance using the same, when manufacturing an aluminum electrolytic capacitor used for various electronic devices. The present invention relates to an inspection device.

  Aluminum electrolytic capacitors have been used mainly for various electronic devices, and the situation has not changed even now, but recently the demand for in-vehicle use has been increasing rapidly. Such an aluminum electrolytic capacitor for in-vehicle use is required to have a higher level of reliability with respect to vibration than ever before, and particularly in the case of an aluminum electrolytic capacitor, a lead wire for caulking connected to an electrode foil is used. How to guarantee the connection state has become an important management item.

  FIG. 7 is a conceptual diagram showing the configuration of a connection resistance inspection apparatus for inspecting the connection state of a lead wire for caulking connected to the electrode foil of a conventional aluminum electrolytic capacitor, and FIG. 8 is an equivalent circuit of FIG. 7 and FIG. 8, 1 is an electrode foil made of aluminum, 2 is a lead wire caulked to the electrode foil 1, 3 is a round bar portion forming the lead wire 2, 3 a The flat part 4 formed by processing a part of this round bar part 3 is a caulking connection part, and the root of the lead wire 2 and the lead wire in order not to include the resistance of the electrode foil 1 as much as possible. The resistance value is measured by bringing the measuring terminals 21 and 22 of the ohmmeter 20 into contact with the electrode foil 1 in the vicinity of the flat portion 3a provided in 2 and the quality is determined by comparing the result with the standard value. It was what I was doing.

As prior art document information related to the invention of this application, for example, Patent Document 1 is known.
Japanese Patent Application Laid-Open No. 07-240354

  However, the above-described conventional method for manufacturing an aluminum electrolytic capacitor has a problem in that it lacks reliability due to large measurement variations in the connection resistance inspection for inspecting the connection state of the lead wire 2 that is caulked to the electrode foil 1. Was.

  That is, in the conventional connection resistance inspection method, the connection resistance between the lead wire 2 and the electrode foil 1 to be measured is R1 (usually 0.3 to 1 mΩ) and the electrode foil resistance between the lead wires 2 is measured as shown in FIG. If the electrode foil resistance from R2 and the caulking connection portion 4 to the measurement terminal 22 is R3, the resistance between the measurement terminals 21 and 22 is the sum of the connection resistance R1 and the electrode foil resistance R3. Here, the electrode foil resistance R3 is 3 to 5 mΩ / cm with a width of 2.5 mm, and varies greatly depending on the contact position of the measurement terminal 22. In addition, since the measurement terminal 22 is brought into contact with the dielectric oxide film layer formed on the surface of the electrode foil 1, the contact resistance R4 between the measurement terminal 22 and the electrode foil 1 varies greatly, and the measurement person determines 0.5 mΩ. It is inevitable that a certain degree of variation occurs, and for this reason, the measurement variation becomes large, and therefore, the reliability is lacking.

  The present invention solves such a conventional problem and stably produces a product excellent in connection reliability and vibration resistance by accurately inspecting the connection state of the lead wire crimped to the electrode foil. It is an object of the present invention to provide an aluminum electrolytic capacitor manufacturing method and a connection resistance inspection apparatus using the same.

  In order to solve the above-mentioned problems, according to the first aspect of the present invention, a plurality of lead wires for connection are connected to a strip-shaped electrode foil at a predetermined interval, and a set of three consecutive lead wires is formed. The center lead wire is to be inspected, a constant voltage is applied between the lead wire to be inspected and one of the lead wires adjacent thereto, the current flowing therethrough is measured, and the inspected Measure the voltage generated between the target lead wire and the other lead wire adjacent to it, and connect the lead wire to be inspected with the electrode foil by calculating the resistance value from this voltage value and the current value. After inspecting the resistance, a capacitor element is formed using the electrode foil to which the lead wire is connected. Subsequently, the capacitor element is housed in a bottomed cylindrical metal case together with a driving electrolyte and sealed. Aluminum electrolytic capacitor This method is a manufacturing method. With this method, the connection resistance between the lead wire and the electrode foil can be accurately measured with a simple configuration and only the measured values of the voltmeter and the ammeter. Since it is possible to perform all connection resistance inspections continuously after caulking the lead wires to the foil, it is possible to improve reliability and yield at the same time without sending defective products to subsequent processes. It has the effect of becoming.

  In the invention according to claim 2 of the present invention, a plurality of lead wires are connected to the strip-shaped electrode foil at a predetermined interval, and the continuous three lead wires are used as one set to connect the central lead wire. A constant current is applied between the lead wire to be inspected and one lead wire adjacent thereto, and between the lead wire to be inspected and the other lead wire adjacent thereto. After measuring the voltage generated in the electrode and determining the resistance value from this voltage value and the applied current value, the connection resistance between the lead wire to be inspected and the electrode foil is inspected, and then the electrode to which the lead wire is connected It is a manufacturing method of an aluminum electrolytic capacitor in which a capacitor element is formed using a foil, and then this capacitor element is housed and sealed in a bottomed cylindrical metal case together with a driving electrolyte. This method allows you to measure Ri simplifies has the effect that current meter it is possible to inexpensively constitute the device from becoming unnecessary.

  According to a third aspect of the present invention, the constant current applied between the lead wire to be inspected and one lead wire adjacent thereto is set to 1A.

  According to the fourth aspect of the present invention, the connection portion determined to be defective cannot be used based on the result of the connection resistance inspection between the lead wire and the electrode foil. And the yield is that the yield can be improved at the same time.

  According to a fifth aspect of the present invention, there is provided a measuring terminal that abuts three lead wires as a set of a plurality of continuous lead wires connected to a strip-shaped electrode foil at a predetermined interval. A DC power source and an ammeter connected between the measuring section provided with the above-mentioned three lead wires and the lead wire in the center portion and one lead wire adjacent thereto, and the lead wire in the center portion And the other lead wire adjacent to the voltmeter and the connection resistance between the voltmeter and the lead wire in the center part to be inspected based on the output from the voltmeter and the ammeter and the electrode foil This is a connection resistance inspection device comprising a determination unit for determining and determining the connection resistance between the lead wire and the electrode foil with a simple configuration, and the lead wire is caulked and connected to the electrode foil. Later, all the connection resistance tests were continued. Since it is possible to perform, with the effect that it is possible to achieve reliability and improvement in yield at the same time.

  According to a sixth aspect of the present invention, there is provided a measuring terminal that abuts three lead wires as a set of three consecutive lead wires connected to the strip-shaped electrode foil at a predetermined interval. A constant current source connected between the lead wire in the central portion of the three lead wires and one lead wire adjacent thereto, and the lead wire in the central portion and the same A voltmeter connected between the other lead wire adjacent to the lead wire, and an output from the voltmeter and a current lead value applied from the constant current source and a central lead wire and electrode foil to be inspected In addition to the operational effects obtained by the invention of the fifth embodiment, this further simplifies the measurement and eliminates the need for an ammeter. Therefore, the device can be configured at a low cost. It has the effect that would be able to.

  The invention according to claim 7 of the present invention has a configuration in which a cutting portion for cutting the tip portion of the lead wire determined to be defective based on the result of the connection resistance inspection between the lead wire and the electrode foil is provided. With this, there is an effect that productivity and yield can be improved at the same time.

  According to an eighth aspect of the present invention, the measurement terminal that contacts the round bar portion constituting the lead wire is formed of conductive rubber, which is one of conductive polymer materials having elasticity. As a result, the round bar portion is not damaged at the time of measurement, so that it is possible to prevent leakage from occurring.

  As described above, the method for manufacturing an aluminum electrolytic capacitor according to the present invention and the connection resistance inspection apparatus using the same have a simple configuration, and the connection resistance between the lead wire and the electrode foil is determined only by the measured values of the voltmeter and ammeter. It becomes possible to measure with high accuracy, and since it is possible to perform all connection resistance inspections continuously after caulking the lead wires to the electrode foil, there is no need to send defective products to subsequent processes. Thus, it is possible to achieve a special effect that the reliability and the yield can be improved at the same time.

(Embodiment 1)
Hereinafter, the first aspect of the present invention will be described with reference to the first embodiment.

  FIG. 1 shows a configuration of a connection resistance inspection apparatus for inspecting a connection state of lead wires for caulking and connecting to electrode foils in a method for manufacturing an aluminum electrolytic capacitor according to Embodiment 1 of the present invention. 2 is a circuit diagram showing an equivalent circuit of FIG. 1. In FIGS. 1 and 2, 1 is an electrode foil made of aluminum, 2 is a lead wire caulked to the electrode foil 1, and 2a is this A lead wire connected by crimping adjacent to the upstream side of the lead wire 2, 2b is a lead wire connected by crimping adjacent to the downstream side, 3 is a round bar portion forming the lead wire 2, 3a is this round A flat part 4 formed by processing a part of the bar part 3 is a caulking connection part.

  5 is a DC power source for applying a constant voltage between the lead wires 2-2a, 6 is an ammeter connected in series to the DC power source 5, 7 and 8 are measurement terminals that are in contact with the lead wires 2 and 2a, 11 Is a voltmeter that measures the voltage between the lead wires 2-2b, 9 and 10 are measurement terminals that contact the lead wires 2 and 2b, respectively, and 12 is a caulking connection based on the outputs from the ammeter 6 and the voltmeter 11 It is a conversion unit for obtaining the connection resistance of the unit 4.

  R1 is a connection resistance of the caulking connection portion 4 of the lead wire 2 in the center of the figure to be inspected, and R3 is a connection resistance of the caulking connection portion 4a of the lead wire 2a connected to the upstream side of the lead wire 2. , R5 is the connection resistance of the caulking connection portion 4b of the lead wire 2b connected to the downstream side of the lead wire 2, R2 is the electrode foil resistance between the caulking connection portions 4-4a, and R4 is between the caulking connection portions 4-4b Electrode foil resistance.

  Using the thus configured connection resistance inspection apparatus according to this embodiment, assuming that the voltage of the DC power supply 5 is V1, the current of the ammeter 6 is I1, and the voltage of the voltmeter 11 is V2, the value of the ammeter 6 is It changes with electrode foil resistance R2 and the connection resistances R1 and R3 of the crimping connection parts 4 and 4a like the following formula.

I1 = V1 / (R1 + R2 + R3)
However, since the connection resistance R1 of the caulking connection portion 4 is R1 = V2 / I1, the connection resistance R1 of the caulking connection portion 4 of the lead wire 2 to be inspected only by the measured values of the voltmeter 11 and the ammeter 6 Can be measured.

  As described above, according to the present embodiment, the connection resistance R1 of the caulking connection portion 4 of the lead wire 2 that is caulked to the electrode foil 1 can be accurately measured by a simple method. Since all the leads can be inspected continuously after caulking the lead wires 2 to 1, no defective products are passed on to the subsequent process, and reliability and yield can be improved at the same time. It is.

(Embodiment 2)
Hereinafter, the second and third embodiments of the present invention will be described with reference to the second embodiment.

  This embodiment has a configuration in which the DC power source of the connection resistance inspection apparatus in the first embodiment is replaced with a constant current source. Since the other configuration is the same as that of the first embodiment, the same parts are not included. The same reference numerals are given and detailed description thereof is omitted, and only different parts will be described below with reference to the drawings.

  FIG. 3 shows the configuration of a connection resistance inspection device for inspecting the connection state of lead wires for caulking connected to electrode foils in the method for manufacturing an aluminum electrolytic capacitor according to Embodiment 2 of the present invention. 4 is a circuit diagram showing an equivalent circuit of FIG. 3. In FIGS. 3 and 4, 13 is a constant current source for applying a constant current between the lead wires 2-2a.

  The connection resistance measurement using the connection resistance inspection apparatus according to the present embodiment configured as described above can be obtained by dividing the voltage of the voltmeter 11 by the set current of the constant current source 13, and in particular, the constant current. When the set value of 13 is set to 1A, the value of the voltmeter 11 becomes the resistance value as it is, so that the conversion unit 12 used in the first embodiment is unnecessary, and the ammeter 6 is also unnecessary. The apparatus configuration can be simplified and made inexpensive.

(Embodiment 3)
Hereinafter, the invention described in the fourth to eighth aspects of the present invention will be described using the third embodiment.

  FIG. 5 is a perspective view of a main part showing the configuration of a connection resistance inspection apparatus according to Embodiment 3 of the present invention. In FIG. 5, 14 is a needle hole processing unit provided with a needle, and 15 is a caulking processing unit. The lead wire 2 is supplied onto the electrode foil 1 from the lead wire supply portion that is not, and the flat portion 3a and the electrode foil 1 are penetrated by the needle hole processing portion 14 at a predetermined position of the flat portion 3a provided on the lead wire 2. The hole forming process is performed, and the portion where the hole is formed is subsequently crimped by the crimping processing unit 15 to form the crimping connection portion 4 to connect the lead wire 2 to the electrode foil 1.

  Subsequently, the lead wire 2 connected to the electrode foil 1 by the caulking connection portion 4 is intermittently conveyed along with the intermittent feeding of the electrode foil 1, and the above-described implementation is performed by the measurement portion 16 including the measurement terminals 7, 8, 9, and 10. The connection resistance inspection is performed by the method described in the first or second embodiment. Based on the inspection result, if the connection resistance is other than the standard value, the tip end portion of the lead wire 2 is cut by the cutting portion 17 provided in the next step. The capacitor element wound by using the electrode foil 1 to which the lead wire 2 whose tip portion has been cut in the subsequent process is connected is defective and cannot be used. This is to make it clear at a glance.

  6 (a) to 6 (c) show the contact state of the measurement terminal of the connection resistance inspection apparatus shown in FIG. 5, in which 2 indicates a lead wire, and this lead wire 2 is generally an iron wire. The resistance is high because the material subjected to the plating process is used. 3 is a round bar portion made of aluminum wire, and 3a is a flat portion obtained by processing a part of the round bar portion 3 into a flat shape. The resistance is small because the cross-sectional area is large, and the flat portion 3a is overlapped on the electrode foil 1. Are connected by caulking. Reference numeral 18 denotes a measurement cradle, and 19 denotes a round bar portion 3 relief groove provided on the cradle 18.

  FIG. 6A shows a measurement method when the resistance of the lead wire 2 is minimized, and the position of the measurement terminal 9 with the narrowed tip is the right side (round bar portion 3 in the figure). Since the resistance component of the lead wire 2 having a high resistance is added when moving in the direction away from the center, it is desirable to be as close to the round bar portion 3 as possible. In this case, one of the two measurement terminals 7 and 9 is used for current supply, and the other is used for voltage measurement. However, the measurement accuracy does not change regardless of how the measurement is shared.

  FIG. 6B shows a measurement method when the resistance of the lead wire 2 is not included, and the measurement terminal 9 having a rounded tip is brought into contact with the flat portion 3a. By doing so, the voltage drop due to the resistance of the lead wire 2 and the round bar portion 3 is excluded from the measured value, so that only the connection resistance can be measured with high accuracy.

  In this method, pressure is applied to the electrode foil 1 through the flat portion 3a during measurement, and the measured value may be lowered depending on the contact pressure of the measurement terminal 9. Therefore, the contact pressure is preferably 10 g or less. Therefore, of the two measurement terminals, it is preferable to use the measurement terminal 7 on the lead wire 2 side capable of increasing the contact pressure for current supply and the measurement terminal 9 on the flat portion 3a side for voltage measurement.

  FIG. 6C shows the measurement terminal 9 made of conductive rubber, which is one of conductive polymer materials having elasticity. In the case of an aluminum electrolytic capacitor, the round bar portion 3 is a sealing rubber (not shown). It is configured to be sealed by being fitted into a through-hole provided in the above-described structure. However, when the round bar portion 3 is damaged during measurement, it may cause leakage. Therefore, by configuring the measurement terminal 9 with an elastic body, the round bar portion 3 is not damaged at the time of measurement, and the voltage drop of the lead wire 2 portion deviates from the measured value by such a measurement method. It becomes possible to measure with high accuracy.

  In addition, when the measurement terminal 9 is made of conductive rubber, since the specific resistance is generally several hundred to several kΩ and a large current cannot flow, the measurement terminal 9 made of conductive rubber is used for voltage measurement. The other measurement terminal 7 is preferably used for supplying current. The cradle 18 and the measurement terminal 9 are preferable because they are made of rubber or elastomer having a hardness of about 70 to 95, so that the lead wire 2 is hardly damaged and easy to handle. .

The method of manufacturing an aluminum electrolytic capacitor and the connection resistance inspection apparatus using the same according to the present invention can accurately measure the connection resistance of a lead wire that is caulked and connected to an electrode foil with a simple configuration to simultaneously improve reliability and yield. Therefore, it is particularly useful when manufacturing an aluminum electrolytic capacitor for in-vehicle use, which is required at a higher level of reliability against vibration than ever before.

The conceptual diagram which showed the structure of the connection resistance test | inspection apparatus by Embodiment 1 of this invention Circuit diagram showing equivalent circuit of FIG. The conceptual diagram which showed the structure of the connection resistance test | inspection apparatus by Embodiment 2 of this invention Circuit diagram showing equivalent circuit of FIG. The principal part perspective view which showed the structure of the connection resistance test | inspection apparatus by Embodiment 3 of this invention. Cross section of the main part showing the contact state of the measurement terminal Conceptual diagram showing the configuration of a conventional connection resistance inspection device Circuit diagram showing equivalent circuit of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electrode foil 2,2a, 2b Lead wire 3 Round bar part 3a Flat part 4 Caulking connection part 5 DC power supply 6 Ammeter 7, 8, 9, 10 Measuring terminal 11 Voltmeter 12 Conversion part 13 Constant current source 14 Needle hole processing Section 15 Caulking section 16 Measuring section 17 Cutting section 18 Receiving base 19 Groove section

Claims (8)

A plurality of lead wires for lead are connected to the strip-shaped electrode foil at a predetermined interval, and three consecutive lead wires are set as one set, and the lead wire in the central portion is the object to be inspected. A constant voltage is applied between the lead wire adjacent to the lead wire and a current flowing through the lead wire is measured, and is generated between the lead wire to be inspected and the other lead wire adjacent thereto. After measuring the voltage and determining the resistance value from the voltage value and the current value, the connection resistance between the lead wire to be inspected and the electrode foil is inspected, and then the capacitor using the electrode foil to which the lead wire is connected A method of manufacturing an aluminum electrolytic capacitor in which an element is formed, and then the capacitor element is housed and sealed in a bottomed cylindrical metal case together with a driving electrolyte. A plurality of lead wires for lead are connected to the strip-shaped electrode foil at a predetermined interval, and three consecutive lead wires are set as one set, and the lead wire in the central portion is the object to be inspected. A constant current is applied between the first lead wire adjacent to the lead wire and a voltage generated between the lead wire to be inspected and the other lead wire adjacent thereto is measured. After inspecting the connection resistance between the lead wire to be inspected and the electrode foil by obtaining the resistance value from the applied current value, a capacitor element is formed using the electrode foil to which the lead wire is connected, and then A method of manufacturing an aluminum electrolytic capacitor in which this capacitor element is housed and sealed in a bottomed cylindrical metal case together with a driving electrolyte. The method for manufacturing an aluminum electrolytic capacitor according to claim 2, wherein a constant current applied between the lead wire to be inspected and one lead wire adjacent thereto is 1A. 3. The method for manufacturing an aluminum electrolytic capacitor according to claim 1, wherein a connection portion determined to be defective cannot be used based on a result of a connection resistance inspection between the lead wire and the electrode foil. A measuring section having measuring terminals that contact three lead wires as a set of a plurality of three lead wires for lead connected to a strip-shaped electrode foil at a predetermined interval; and the three leads Among the wires, the DC power supply and ammeter connected between the lead wire in the center and one lead wire adjacent to it, and between the lead wire in the center portion and the other lead wire adjacent thereto A connection resistance test consisting of a voltmeter connected to the voltmeter and a determination unit for determining and determining the connection resistance between the lead wire and the electrode foil at the center to be inspected based on the output from the voltmeter and the ammeter apparatus. A measuring section having measuring terminals that contact three lead wires as a set of a plurality of three lead wires for lead connected to a strip-shaped electrode foil at a predetermined interval; and the three leads Among the wires, a constant current source connected between the lead wire in the central portion and one lead wire adjacent thereto, and also connected between the lead wire in the central portion and the other lead wire adjacent thereto A determination unit for determining and determining the connection resistance between the lead wire and the electrode foil in the central part to be inspected based on the output from the voltmeter and the current value applied from the constant current source Connection resistance inspection device. The connection resistance inspection device according to claim 5 or 6, further comprising a cutting portion for cutting a tip portion of the lead wire determined to be defective based on a result of the connection resistance inspection between the lead wire and the electrode foil. 7. The connection resistance inspection apparatus according to claim 5, wherein the measurement terminal that comes into contact with the round bar portion constituting the lead wire is formed of conductive rubber that is one of conductive polymer materials having elasticity.

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