JP2002184658A - Device and method for inspecting electrolytic capacitor for airtightness - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device and method for inspecting electrolytic capacitor for airtightness, which can be incorporated in the production line of an electrolytic capacitor for performing 100% inspections on the capacitor for airtightness. SOLUTION: The device for inspecting electrolytic capacitor for airtightness is provided with a hermetically sealed container 20, which forms a hermetically sealed space after housing the electrolytic capacitor 1, and a sensing device 21 which is installed to the container 20 for inspecting the air existing in the container 20 for confirming the presence/absence of specific components. The capacitor 1 is housed in the container 20, after the capacitor 1 has been heat- treated, and the airtightness of the capacitor 1 is inspected for propriety, by confirming the presence/absence of the specific component in the air existing in the container 20, by means of the sensing device 21, after a prescribed period of time has elapsed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airtightness inspection apparatus for an electrolytic capacitor and an airtightness inspection method for an electrolytic capacitor.

[0002]

2. Description of the Related Art As shown in FIG. 5, an ordinary electrolytic capacitor 1 is formed by winding an anode cathode foil 3 and a cathode electrode foil 4 made of a valve metal such as aluminum through a separator 5 to form a capacitor element. 2 and the capacitor element 2
And the capacitor element 2
Is stored in a bottomed cylindrical outer case 7. The opening of the outer case 7 is provided with a sealing member made of elastic rubber or a sealing member 8 in which an elastic rubber and a hard resin plate are bonded to each other. And sealed.

The leads 6 electrically connected to the bipolar electrode foils 3, 4 are drawn out from the end face of the capacitor element 2, penetrate through the sealing member 8, and are led out. In the case of a relatively large electrolytic capacitor, the lead 6 pulled out from the end face of the capacitor element 2 is connected to a terminal portion 9 fixed to a sealing member 8 in which elastic rubber and a hard resin plate are bonded.
Are connected via rivets or the like.

Alternatively, a capacitor element 2 in which an anode electrode foil 3 and a cathode electrode foil 4 are wound with a separator 5 interposed therebetween,
Impregnated with a heated and melted TCNQ complex salt, 3,4-
There is a so-called solid electrolytic capacitor, such as one in which polyethylene dioxythiophene impregnated with ethylene dioxythiophene and an oxidizing agent and produced by a chemical polymerization reaction in the capacitor element 2 is held as a solid electrolyte layer by a separator 5. The electrolytic capacitor is also housed in a bottomed cylindrical outer case 7 like the above electrolytic capacitor, and the opening of the outer case 7 is sealed and sealed with a sealing member 8.

In order to check the airtightness of the electrolytic capacitor 1, a method has been used in which the electrolytic capacitor 1 is immersed in a container containing hot water and air bubbles that come out of the hot water are visually checked.

[0006] Alternatively, as in the invention described in JP-A-10-197389, a sealed container for accommodating an electrolytic capacitor and an air injection device provided in the sealed container and for injecting compressed air into the sealed container. Inspection is performed by an airtightness inspection device including an inlet and a pressure gauge that detects a change in air pressure in the closed container after a lapse of a predetermined time of a fixed amount of compressed air injected into the closed container through the air inlet. However, if the electrolytic capacitor being inspected is a poorly airtight product, the compressed air will enter the electrolytic capacitor and the air pressure in the sealed container will change, so the pressure gauge will detect this change in air pressure. It is known that the quality of a product is determined as good or defective.

As another method, Japanese Patent Application Laid-Open No. 10-28
As in the inventions described in JP-A-1916 and JP-A-10-284356, a liquid tank in which an electrolytic capacitor is immersed in a stored liquid is arranged in a closed space, and the inside of the closed space is evacuated by drawing air. The presence or absence of air bubbles generated from the electrolytic capacitor when pressure is applied, and one that determines the sealing performance of the electrolytic capacitor, and one or more that are temporarily fixed on a fixed base so that the sealing part is located on the lower surface side After arranging the electrolytic capacitor in the enclosed space, the presence or absence of the driving electrolyte leaking from the electrolytic capacitor when the interior of the enclosed space is evacuated to a negative pressure is visually checked to determine its quality. Something to determine is done.

[0008]

However, the above-mentioned conventional airtightness inspection method has the following problems.

That is, in the method using hot water, if a large amount of aluminum electrolytic capacitors are put in hot water, it becomes difficult to control the temperature. In addition, the method uses a liquid tank in a closed space with a negative pressure or leaks from the electrolytic capacitors. Similar to the method of visually confirming the presence or absence of the driving electrolyte,
Since the detection method has to rely on visual observation, it is very difficult to incorporate it into a production line and perform 100% inspection.

In a method of injecting compressed air into a closed container containing an electrolytic capacitor and detecting a change in air pressure in the closed container after a lapse of a predetermined amount of compressed air, a sealing member of the electrolytic capacitor is provided. Although the airtight defect due to the defect near the outside can be detected, it is not suitable for detecting the temporal airtight defect due to the defective portion 10 near the inside of the sealing member 8 as shown in FIG.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide an airtightness inspection apparatus and an airtightness inspection method for an electrolytic capacitor which can be incorporated into a production line to perform a 100% inspection of the airtightness of the electrolytic capacitor. I have.

[0012]

According to the first aspect of the present invention, a capacitor element is housed in an outer case, and an electrolytic capacitor in which an opening of the outer case is sealed with a sealing member is housed and hermetically sealed. An airtightness inspection device for an electrolytic capacitor, comprising: a closed container forming a space; and a sensing device installed in the closed container and detecting the presence or absence of a specific component in air in the closed container, according to claim 6 of the present invention. Then, the capacitor element was housed in an outer case, and the electrolytic capacitor in which the opening of the outer case was sealed with a sealing member was housed in a sealed container after heat treatment, and after a predetermined time in air in the sealed container. The present invention provides an airtightness inspection method for an electrolytic capacitor in which the presence or absence of a specific component is checked by a sensing device installed in a closed container to check whether the electrolytic capacitor is airtight.

Here, the specific component is a component contained in the driving electrolyte used for the electrolytic capacitor, a hydrogen gas generated by an electrochemical reaction inside the electrolytic capacitor, or a solid such as a TCNQ complex salt or polyethylene dioxythiophene. In addition to components contained in the electrolyte itself, gases generated in the course of their generation can be exemplified, but not limited thereto, and refers to all gases generated inside the outer case of the electrolytic capacitor.

According to this configuration, if the electrolytic capacitor is good, even if the electrolytic capacitor is subjected to a heat treatment to increase the internal pressure of the electrolytic capacitor, the specific component is detected in the air in the closed container containing the electrolytic capacitor. On the other hand, if the electrolytic capacitor is defective in airtightness, a specific component inside the electrolytic capacitor leaks into the air in the sealed container after a predetermined time has elapsed, and the specific component is detected by the sensing device, and the defective component is detected. In order to make a pass / fail judgment in a short time, by incorporating this apparatus into a production line, a 100% inspection of the airtightness of the electrolytic capacitor can be realized.

According to a second aspect of the present invention, there is provided an airtightness inspection apparatus for an electrolytic capacitor in which a heating means for performing a heat treatment on an electrolytic capacitor is provided in the closed container. An electrolytic capacitor that is housed and the opening of this outer case is sealed with a sealing member,
After being housed in a closed container and subjected to a heat treatment by a heating means installed in the closed container, the presence or absence of a specific component in the air in the closed container after a predetermined time has elapsed is confirmed by a sensing device installed in the closed container, and the electrolysis is performed. The present invention provides an airtightness inspection method for an electrolytic capacitor for inspecting the airtightness of a capacitor.

According to this configuration, the heat treatment and the inspection of the electrolytic capacitor can be performed in the same apparatus, and if the electrolytic capacitor is a good product, the electrolytic capacitor can be heat-treated to increase the internal pressure of the electrolytic capacitor. However, the specific component is not detected in the air inside the closed container containing the electrolytic capacitor, while if the electrolytic capacitor is defective in the airtightness, the specific component inside the electrolytic capacitor is not included in the air inside the closed container after a predetermined time has elapsed. Is leaked, and the specific component is detected by the sensing device, and the quality of the defective product is determined in a short time. Therefore, by incorporating this device into the production line, it is possible to realize the 100% inspection of the airtightness of the electrolytic capacitor.

According to a third aspect of the present invention, there is provided a frame member for housing at least an opening of an electrolytic capacitor in which a capacitor element is housed in an outer case, and the opening of the outer case is sealed with a sealing member. 9. An airtightness inspection device for an electrolytic capacitor, comprising: a sensing device installed for detecting presence or absence of a specific component in air surrounded by a frame member.
According to the above, the capacitor element is housed in an outer case, and after the heat treatment is performed on the electrolytic condenser in which the opening of the outer case is sealed with a sealing member, the frame member on which the sensing device is disposed is at least the opening of the electrolytic capacitor. To cover the
The method according to claim 9, wherein the airtightness of the electrolytic capacitor is checked by checking the presence or absence of a specific component in the air surrounded by the frame member after a predetermined time has passed by the sensing device to check whether the electrolytic capacitor is airtight. The capacitor element is housed in an outer case, and an electrolytic capacitor in which the opening of the outer case is sealed with a sealing member, a frame member on which the sensing device is arranged, is arranged so as to cover at least the opening of the electrolytic capacitor, After performing heat treatment on the electrolytic capacitor, the airtightness inspection of the electrolytic capacitor is performed by checking the presence or absence of a specific component in the air surrounded by the frame member after a lapse of a predetermined time by the sensing device to check whether the electrolytic capacitor is airtight. To serve the method.

According to this configuration, if the electrolytic capacitor is a good product, even if the electrolytic capacitor is subjected to a heat treatment to increase the internal pressure of the electrolytic capacitor, the electrolytic capacitor remains in the air surrounded by the frame member covering the opening of the electrolytic capacitor. The specific component is not sensed.On the other hand, if the electrolytic capacitor is defective in airtightness, the specific component inside the electrolytic capacitor leaks into the air surrounded by the frame member after a predetermined time has elapsed, and the specific component is detected by the sensing device. By incorporating this device into a production line in order to detect and determine whether or not a defective product is good or not in a short time, it is possible to realize a 100% inspection of the airtightness of the electrolytic capacitor.

The frame member may be provided with an elastic member that is in close contact with the opening of the electrolytic capacitor. According to this configuration, the detection accuracy of the specific component is further improved.

Further, in all of the above-mentioned inventions, a heat treatment is performed on the electrolytic capacitor before or after the heat treatment is performed by using an airtightness inspection device for the electrolytic capacitor provided with a pressing jig for pressing the opening of the electrolytic capacitor at a constant pressure. Alternatively, an airtight inspection method for the electrolytic capacitor in which the sealing member of the electrolytic capacitor is pressed with a predetermined pressure may be employed. According to this configuration,
If the electrolytic capacitor has poor airtightness due to the external pressure by the pressing jig, the leakage of specific components inside the electrolytic capacitor is promoted, and the time for quality determination can be further reduced.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment of the present invention. As shown in FIG. 5, an electrolytic capacitor 1 is formed by winding an anode cathode foil 3 and a cathode electrode foil 4 made of a valve metal such as aluminum through a separator 5 to form a capacitor element 2. The element 2 is impregnated with a driving electrolyte, and the capacitor element 2 is housed in a bottomed cylindrical outer case 7. The outer case 7 is made of aluminum, and an opening of the outer case 7 is provided with a sealing member 8 in which elastic rubber and a hard resin plate are bonded. The opening of the outer case 7 is subjected to a drawing process on its end face and sealed to form the electrolytic capacitor 1.

In the first embodiment, the airtight inspection of the electrolytic capacitor 1 is performed by first subjecting the electrolytic capacitor 1 to a heat treatment at about 50 ° C. to 120 ° C. or, if necessary, to a constant voltage in addition to the heat treatment. Is applied, and housed in a closed container 20 as shown in FIG. This heat treatment may be performed in a re-chemical conversion step in which heat treatment is performed by applying a constant voltage in the production of the electrolytic capacitor.

The airtight container 20 only needs to ensure a certain airtightness, and a sensing device 21 for detecting a specific component in the air in the airtight container 20 is attached. This sensing device 2
Reference numeral 1 denotes a component contained in a driving electrolytic solution used for the electrolytic capacitor 1, hydrogen gas generated by an electrochemical reaction inside the electrolytic capacitor 1, or a solid electrolyte itself such as a TCNQ complex salt or polyethylene dioxythiophene. In addition to the components, they are for sensing gases generated during the production process, and the like, and a sensing unit 22 is inserted into the closed container 20. The sensing device 21 may be a sensing device that senses a single specific component or a sensing device that senses a plurality of specific components. Further, a plurality of sensing devices for sensing different specific components may be provided as needed. In the first embodiment, a hydrogen gas sensor is used.

Then, the heat-treated electrolytic capacitor 1 is housed in a closed container 20, and the presence or absence of a specific component (hydrogen gas in this embodiment) in the closed container 20 is detected by the sensing device 21. At this time, when a specific component in the closed container 20 is sensed after a lapse of a predetermined time, the electrolytic capacitor 1 to be inspected has the internal specific component leaked to the outside due to a pressure increase inside the electrolytic capacitor 1 due to the heat treatment. No, it is determined that the airtightness is poor.

If the electrolytic capacitor 1 to be inspected is a non-defective product, even if the pressure inside the electrolytic capacitor 1 increases due to the heat treatment, the specific components inside do not leak out.
Even after the elapse of the predetermined time, the specific component is not detected in the closed container 20.

FIG. 2 shows an airtightness inspection apparatus for an electrolytic capacitor according to another embodiment of the present invention. This airtightness inspection apparatus is the same as the airtightness inspection apparatus shown in the first embodiment of the present invention shown in FIG. A heating device 23 such as an electric heater is added to the inspection device. After the electrolytic capacitor 1 is accommodated in the closed container 20, the electrolytic capacitor 1 is subjected to a heat treatment with an electric heater (the heating device 23) or the like, and a predetermined process is performed as it is. After the lapse of time, the presence or absence of the specific component in the closed container 20 is inspected for the specific component in the closed container 20 by the sensing device 21 attached to the closed container 20.

In this embodiment, similarly to the first embodiment, if no specific component is detected in the closed container 20 after a predetermined time has elapsed, the electrolytic capacitor 1 by the heat treatment is used.
It can be confirmed that the specific component in the electrolytic capacitor 1 does not leak to the outside even when the internal pressure increases. In the case of this embodiment, after the heat treatment for the electrolytic capacitor 1, the inspection can be performed in a state where there is no time lag,
More precise inspection can be performed in combination with the temperature control of the heating means 23.

FIG. 3 shows another embodiment of the present invention, in which the airtightness of the entire electrolytic capacitor is not inspected as in the first embodiment, but only the opening of the electrolytic capacitor 1 is framed. The airtightness inspection is performed in a state where the airtightness is covered by the member 24.

That is, a frame member 24 having an elastic member 25 which is in close contact with the opening of the electrolytic capacitor 1 is disposed at the opening of the electrolytic capacitor 1 which has been subjected to the heat treatment, and is pressed against the electrolytic capacitor 1 with a constant pressure. A closed space 26 is formed by the opening of the electrolytic capacitor 1 and the frame member 24, and the presence or absence of a specific component in the closed space 26 after a lapse of a predetermined time is inspected by the sensing device 21.

In this embodiment, similarly to the first embodiment, if a specific component is not detected in the space 26 enclosed by the opening of the electrolytic capacitor 1 and the frame member 24 after a predetermined time has elapsed. Even if the internal pressure in the electrolytic capacitor 1 increases due to the heat treatment, it can be confirmed that the specific components inside the electrolytic capacitor 1 do not leak out. Since the airtightness inspection can be performed without housing the electrolytic capacitor 1 in a closed container, the heat treatment to the electrolytic capacitor 1 may be performed before or after the frame member 24 is installed, and the manufacturing facility is simplified. .

FIG. 4 shows another embodiment of the present invention, in which an airtightness inspection apparatus is provided with a pressing jig 28 for pressing the opening of the electrolytic capacitor 1 at a constant pressure. That is, a frame member 27 that covers the opening of the electrolytic capacitor 1 is disposed in the vicinity of the opening of the electrolytic capacitor 1, and the electrolytic jig 1 is pressed by a pressing jig 28 installed on the frame member 27.
Is pressed with a constant pressure (50 to 80 N).

In this embodiment, as in the first embodiment, if a specific component is not detected in the space 29 surrounded by the opening of the electrolytic capacitor 1 and the frame member 27 after a lapse of a predetermined time, the electrolytic solution is removed. Even when the internal pressure in the capacitor 1 rises, it can be confirmed that the specific components inside the electrolytic capacitor 1 do not leak to the outside. Then, the increase in the internal pressure of the electrolytic capacitor 1 due to the heat treatment is assisted by the pressing of the pressing jig 28, so that a quicker inspection can be performed.

[0033]

As described above, according to the present invention, there is provided a sealed container in which a capacitor element is housed in an outer case and an electrolytic capacitor in which the opening of the outer case is sealed with a sealing member is formed to form a sealed space. The airtightness of an electrolytic capacitor comprising a frame member installed near the opening of the electrolytic capacitor and a sensing device installed in a closed container or frame member to check for the presence of a specific component in air in the closed container or frame member. Using an inspection device, heat-treat the electrolytic capacitor and place it in a closed container, or install a frame member near the opening of the electrolytic capacitor, and check for the presence or absence of specific components after a predetermined time in air in the closed container or the frame member. This is to check the airtightness of the electrolytic capacitor by checking with a sensing device installed on the closed container or frame member.If a specific component in the closed container or frame member is detected after a predetermined time has elapsed Within a particular component of the electrolytic capacitor became inspected is that the external leakage, it is possible to change the determination of the poor airtightness. On the other hand, if the electrolytic capacitor to be inspected is a good one, even if the pressure inside the electrolytic capacitor rises, the specific components inside do not leak out, and even after a predetermined time, the sealed container or the frame member The specific component is not detected in the inside, and it can be determined in a short time whether the product is good or defective. Therefore, by incorporating this device into a production line, it is possible to perform a 100% inspection of the airtightness of the electrolytic capacitor.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a configuration of an electrolytic capacitor airtightness inspection apparatus showing an embodiment according to the present invention.

FIG. 2 is a sectional view showing the configuration of an airtightness inspection device for an electrolytic capacitor showing another embodiment according to the present invention.

FIG. 3 is a sectional view showing the configuration of an airtightness inspection device for an electrolytic capacitor showing another embodiment according to the present invention.

FIG. 4 is a sectional view showing the configuration of an electrolytic capacitor airtightness inspection apparatus showing another embodiment according to the present invention.

FIG. 5 is a sectional view showing a general electrolytic capacitor.

FIG. 6 is a partial sectional view showing a cause of poor airtightness of a general electrolytic capacitor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrolytic capacitor 2 Capacitor element 3 Anode electrode foil 4 Cathode electrode foil 5 Separator 6 Lead 7 Outer case 8 Sealing member 9 Terminal 10 Defective part 20 Sealing container 21 Sensing device 22 Sensing part 23 Heating means 24 Frame member 25 Elastic member 26 Space 27 Frame member 28 Pressing jig 29 Space

Claims (10)

[Claims] 1. A capacitor element is housed in an outer case,
A sealed container that forms an enclosed space by housing an electrolytic capacitor in which the opening of the outer case is sealed with a sealing member, and a sensing device that is installed in the sealed container and inspects the presence or absence of a specific component in air in the sealed container. An airtightness inspection device for an electrolytic capacitor comprising: 2. The airtightness inspection apparatus for an electrolytic capacitor according to claim 1, wherein a heating means for performing a heat treatment on the electrolytic capacitor is provided in the closed container. 3. A capacitor element is housed in an outer case,
A frame member that covers at least the opening of the electrolytic capacitor in which the opening of the outer case is sealed with a sealing member, and a sensing device that is installed on the frame member and inspects for the presence or absence of a specific component in the air surrounded by the frame member. An airtightness inspection device for an electrolytic capacitor comprising: 4. The airtightness inspection apparatus for an electrolytic capacitor according to claim 3, wherein the frame member includes an elastic member that is in close contact with an opening of the electrolytic capacitor. 5. The airtightness inspection apparatus for an electrolytic capacitor according to claim 1, further comprising a pressing jig for pressing an opening of the electrolytic capacitor with a constant pressure. 6. A capacitor element is housed in an outer case,
The electrolytic capacitor in which the opening of the outer case was sealed with a sealing member was housed in a sealed container after heat treatment, and the presence or absence of a specific component after a predetermined time in air in the sealed container was set in the sealed container. A method for checking the tightness of an electrolytic capacitor by checking the airtightness of the electrolytic capacitor by checking with a sensing device. 7. A capacitor element is housed in an outer case,
After the electrolytic capacitor in which the opening of the outer case is sealed with a sealing member is housed in a closed container and subjected to a heat treatment by a heating means installed in the closed container, after a predetermined time in air in the closed container, A method for checking the tightness of an electrolytic capacitor by checking the presence or absence of a specific component with a sensing device installed in a closed container. 8. A capacitor element is housed in an outer case,
After performing heat treatment on the electrolytic capacitor in which the opening of the outer case is sealed with a sealing member, a frame member in which the sensing device is disposed is disposed so as to cover at least the opening of the electrolytic capacitor, and is surrounded by the frame member. An airtightness inspection method for an electrolytic capacitor, wherein the airtightness of the electrolytic capacitor is inspected by checking the presence or absence of a specific component after a predetermined time in the air using the sensing device. 9. A capacitor element is housed in an outer case,
In the electrolytic capacitor in which the opening of the outer case is sealed with a sealing member, a frame member in which the sensing device is arranged is arranged so as to cover at least the opening of the electrolytic capacitor,
After subjecting the electrolytic capacitor to a heat treatment, the airtightness of the electrolytic capacitor is checked by checking the presence or absence of a specific component in the air surrounded by the frame member after a predetermined time has passed by the sensing device to check whether the electrolytic capacitor is airtight. Method. 10. The method according to claim 6, wherein the sealing member of the electrolytic capacitor is pressed with a predetermined pressure after or before the heat treatment.