JP2000049059A - Manufacture of aluminum electrolytic capacitor and its manufacturing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for accurately manufacturing an aluminum electrolytic capacitor in a short time including a capacitor element impregnation with an electrolyte solution and moreover for which the manufacturing facility be reduced in size. SOLUTION: After a capacitor element 1 is impregnated in an electrolyte solution 9 in an impregnating bath 2, it is picked up from the impregnating bath 2, and the amount of electrolyte solution impregnated in the capacitor element 1 is adjusted to a specified amount. Thus the capacitor element 1 can be impregnated with the electrolyte solution 9 in a very short time and accurately.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aluminum electrolytic capacitor used for various electronic devices, and more particularly to a method of manufacturing an aluminum electrolytic capacitor mainly using a method of impregnating a capacitor element with an electrolytic solution and an apparatus for manufacturing the same. .

[0002]

2. Description of the Related Art A conventional method of manufacturing this type of aluminum electrolytic capacitor will be described with reference to the drawings. FIG.
(A) and (b) show an impregnating device for impregnating the capacitor element with an electrolytic solution.
1 is a capacitor element formed by winding an anode foil and a cathode foil with a separator interposed therebetween, 32
Is an impregnation tank for impregnating the capacitor element 31 with an electrolyte, 33 is a vacuum pump connected to the impregnation tank 32, 34 is an electrolyte tank filled with an electrolyte 35, and 36 is an open / close valve.

Next, a method for impregnating the capacitor element 31 with the electrolytic solution 35 by using the impregnating apparatus thus constructed will be described. First, as shown in FIG. And the pressure inside the impregnation tank 32 is reduced to 5300 Pa (about 40 mmHg) or less by the vacuum pump 33. Next, as shown in FIG. 15B, the electrolytic solution 35 is injected into the impregnating tank 32 from the electrolytic solution tank 34, and then the impregnating tank 32 is opened to the atmospheric pressure state. 35 was impregnated.

However, in such a vacuum impregnation method, when the electrolytic solution 35 is sufficiently impregnated inside the capacitor element 31, the capacitor element 31 is immersed in the electrolytic solution 35 after the vacuum impregnation is performed. Since it is necessary to leave it for a long time, the productivity of the aluminum electrolytic capacitor is significantly reduced.

[0005] Further, in this vacuum impregnation method, since the impregnation time is long, equipment for winding an anode foil and a cathode foil having lead wires for external drawing with a separator interposed therebetween is used. And inserting the wound capacitor element 31 into a bottomed cylindrical case, and connecting the equipment for sealing the opening of the case with a sealing member as a series of equipment is extremely difficult in terms of equipment configuration. And
This not only increases the size of the equipment, but also makes it difficult to suppress variations in the amount of the electrolytic solution 35 impregnated in the capacitor element 31, and furthermore, the capacitor element 31 is kept in the electrolytic solution 35 exposed to the atmosphere for a long time. Since it has to be immersed, there is also a problem that it is difficult to cope with a change in the moisture content of the electrolytic solution 35 in the impregnation tank 32.

Further, in the capacitor element 31 having a high viscosity of the electrolytic solution 35 to be used, there is another problem that insufficient impregnation adversely affects electric characteristics such as capacitance and dielectric loss (tan δ).

Therefore, in order to improve these problems, the capacitor element 31 is formed by a method as shown in FIG.
A method of impregnating the electrolyte solution 35 with the electrolyte solution has been proposed. That is, first, as shown in FIG.
1 is put into the impregnation tank 32, and then the pressure inside the impregnation tank 32 is reduced to 5300 Pa (about 40 mmHg) or less by the vacuum pump 33, whereby the air in the capacitor element 31 is evacuated.

Next, as shown in FIG. 16B, the electrolytic solution 35 is forcibly injected from the electrolytic solution tank 34 into the impregnation tank 32 by using a pressure feed pump 37, thereby forming the capacitor element 3
1 is impregnated with the electrolytic solution 35. Then, once the impregnation tank 32
The inside of the impregnation tank 32 is filled with the electrolyte 35 by injecting the electrolyte 35 in the electrolyte tank 34 by a pressure feed pump 37 into the gap located at the upper part of the impregnation tank 32, Thereafter, from this state, as shown in FIG.
The pressure of [10 × 10 ^{5 to} 500 × 10 ⁵ Pa (approximately 10 to 500 kgf / cm ² )] is applied to the electrolyte 35 itself in the impregnation tank 32 by pumping the electrolyte 35 in the inside. 31 indicates the liquid pressure of the electrolytic solution 35, that is, [10 × 10 ^{5 to} 500 × 10 ⁵ Pa (about 1 × 10 ⁵ Pa).
0 to 500 kgf / cm ² )], so that the electrolytic solution 35 held in the capacitor element 31 is instantaneously impregnated into the inside of the capacitor element 31.

[0009]

However, in the above-mentioned conventional method for manufacturing an aluminum electrolytic capacitor, even when the vacuum impregnation method and the pressurization method shown in FIG. 16 are combined, the impregnation time can be greatly reduced. However, there is a quality problem that the electrolytic solution 35 is excessively impregnated into the capacitor element 31 more than the vacuum impregnation method. In the life test of the aluminum electrolytic capacitor assembled in such a state, the The bottomed cylindrical case that swells, or the capacitance or dielectric loss (tan δ)
However, there is a problem that the variation of the electrical characteristics such as the above becomes large. In addition, as a problem on the manufacturing apparatus, the pressure pump 3
In the case where the pressure of the electrolyte 35 itself is increased in step 7, when a part of the electrolyte 35 is broken due to a tear in a pipe or the like, there is a problem that the electrolyte 35 having high-pressure energy is scattered around.

When the electrolytic solution 35 is injected into the upper gap (atmospheric pressure) of the impregnation tank 32, the air in the upper gap is compressed and an air layer having high-pressure energy is formed above the impregnation tank 32. Is left, and this air is
Therefore, it is extremely difficult to continuously fill and pressurize the electrolytic solution 35 by the pressure feed pump 37.

Therefore, in order to solve these problems, development of equipment capable of continuously filling and pressurizing the electrolytic solution 35 into the impregnation tank 32, and a pressurizing method capable of instantaneously increasing the pressure. There are many technical issues, such as establishment of a small-diameter and short-distance piping system that can use a large number of electrolytes 35 and establishment of a method that can discharge the electrolyte 35 inside the impregnation tank 32 in a short time. It was.

On the other hand, when the pressure is increased by pushing the electrolyte 35 by the pressure pump 37, the pressure rise curve and the set value cannot be easily changed, so that it is most suitable for a wide variety of electrolytes and materials constituting capacitor elements. There is also a problem that it is difficult to establish appropriate impregnation conditions.

[0013]

In order to solve the above-mentioned problems, a method of manufacturing an aluminum electrolytic capacitor according to the present invention is to reduce the pressure in an impregnation tank containing a capacitor element and fill the impregnation tank with an electrolytic solution. After the electrolytic solution is impregnated in the capacitor element by pressurizing the electrolytic solution, the amount of the electrolytic solution impregnated in the capacitor element is adjusted and then incorporated in the case.

According to this manufacturing method, since the electrolytic solution held by the capacitor element is adjusted to a predetermined amount and then assembled, an aluminum electrolytic capacitor with little variation in electric characteristics and stable quality can be obtained. Instead, the electrolytic solution can be accurately impregnated into the capacitor element in a very short time, so that the manufacturing equipment can be downsized.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the first aspect of the present invention, a capacitor element is formed by winding an anode foil and a cathode foil provided with external lead wires with a separator interposed therebetween. After forming the capacitor element in the impregnation tank, the inside of the impregnation tank is depressurized, and then the electrolyte is filled in the entire impregnation tank in the depressurized state, and the electrolyte is pressurized. After the capacitor element is impregnated with the electrolytic solution, the electrolytic solution in the impregnating tank is removed and the pressure in the impregnating tank is returned to the atmospheric pressure.Then, the capacitor element impregnated with the electrolytic solution is taken out of the impregnating tank and the capacitor is removed. Adjust the amount of electrolyte impregnated in the element to a predetermined amount,
This method is a method for manufacturing an aluminum electrolytic capacitor in which a capacitor element having an adjusted amount of electrolyte is inserted into a bottomed cylindrical case, and an opening of the case is sealed with a sealing member. In order to assemble after adjusting the electrolyte held by to a predetermined amount,
Small variations in electrical characteristics, not only can obtain an aluminum electrolytic capacitor of stable quality, but also the impregnation of the capacitor element with the electrolytic solution in a very short time with high precision allows the production equipment to be downsized. It has the effect of being able to.

According to a second aspect of the present invention, in the first aspect, a capacitor element having a terminal plate connected to a terminal wire connected to a lead wire drawn from the capacitor element is used as the capacitor element. Things,
According to this manufacturing method, even when a capacitor element with a terminal plate is used, the same operation as the operation according to the first aspect of the present invention is obtained.

According to a third aspect of the present invention, in the first or the second aspect of the present invention, when the electrolytic solution is impregnated into the capacitor element in the impregnation tank in a pressurized state, the electrolytic solution is heated to a temperature higher than room temperature. This manufacturing method has an effect that the electrolytic solution can be easily and accurately impregnated with this manufacturing method.

According to a fourth aspect of the present invention, there is provided an element assembling section for assembling a capacitor element by winding an anode foil and a cathode foil having lead wires for external lead-out with a separator interposed therebetween. An impregnating section for impregnating the assembled capacitor element with an electrolytic solution using an impregnation tank, a liquid amount adjusting section for adjusting the amount of the electrolytic solution impregnated in the capacitor element, and a capacitor element impregnated with the electrolytic solution. This is a manufacturing apparatus having a configuration including an assembly portion that is inserted into a bottomed cylindrical case and seals the opening of the case, and the capacitor element can be accurately impregnated with the electrolytic solution in a very short time. Therefore, the impregnating tank is
It can be downsized to the size of 00 to 1/300,
This has the effect that the entire equipment can be downsized.

According to a fifth aspect of the present invention, in accordance with the fourth aspect of the present invention, there is provided a pressure reducing mechanism in which the impregnating section decompresses the inside of the impregnating tank, an electrolytic solution filling mechanism for filling the impregnating tank with the electrolytic solution, It is equipped with an electrolytic solution pressurizing mechanism that pressurizes the electrolytic solution filled in the tank and a control mechanism that controls each of these operations, so that the electrolytic solution in the impregnation tank can be in direct contact with the atmosphere. In addition, since the electrolytic solution can be filled in the capacitor element in a short time, an aluminum electrolytic capacitor having a stable quality can be obtained.

According to a sixth aspect of the present invention, in the fifth aspect of the present invention, an air cylinder is used as an electrolyte pressurizing mechanism, and a speed controller is provided in an air introduction path of the air cylinder to connect a piston in the cylinder. It is driven and has the effect that the pressure and the rate of pressure rise of the electrolyte filled in the impregnation tank can be easily adjusted.

According to a seventh aspect of the present invention, in the fifth aspect of the present invention, a motor drive system for driving a piston in a cylinder by a motor is used as an electrolyte pressurizing mechanism, and a servo motor is used as the motor. The piston is driven in the cylinder, and has the same operation as the operation according to the sixth aspect of the present invention.

According to an eighth aspect of the present invention, in accordance with the fourth aspect of the present invention, a holding unit for individually holding the capacitor elements impregnated with the liquid amount adjusting unit, and a suction mechanism connected to the holding unit. This has the effect that the amount of the electrolytic solution impregnated in the capacitor element can be accurately adjusted to a predetermined amount.

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

FIGS. 1 to 6 show an impregnating device for impregnating a capacitor element with an electrolytic solution in the method of manufacturing an aluminum electrolytic capacitor according to the embodiment.
In the figure, 1 is a capacitor element formed by winding an anode foil and a cathode foil with a separator interposed therebetween, 2 is an impregnation tank for impregnating the capacitor element 1 with an electrolytic solution, and 5 is A vacuum pump connected to the impregnation tank 2 via a vacuum valve 3 and a sensor 4 for measuring the absolute vacuum pressure, 6 is an electrolyte filling section, 7 is an electrolyte pressurization section, 8 is an electrolyte supply valve, and 9 is an electrolyte supply valve. Liquid.

Next, a method for impregnating the capacitor element 1 with the electrolytic solution 9 by using the impregnating apparatus thus constructed will be described. First, as shown in FIG. 1, the capacitor element 1 is put in the impregnation tank 2. After that, as shown in FIG. 2, the vacuum pump 5 is driven to open the vacuum valve 3 so that
By reducing the pressure to 0 Pa (about 20 mmHg) or less, the air in the capacitor element 1 is diffused and diffused. Next, as shown in FIG.
Is opened, and the electrolytic solution filling section 6 fills the impregnation tank 2 with the electrolytic solution 9 so as to be full.

Thereafter, after confirming that the inside of the impregnation tank 2 is fully filled with the electrolytic solution 9, as shown in FIG. The pressure inside the impregnation tank 2 is instantaneously increased to about 1 (MP) by forcibly pushing the inside of the impregnation tank 2 filled with the electrolyte 9 by the electrolyte pressurizing section 7.
a) The electrolyte solution 9 is instantaneously impregnated from both ends into the inside of the capacitor element 1 by increasing the pressure to more than (10 (kgf / cm ² )) and keeping the increased internal pressure of the impregnation tank 2 for a certain period of time. Things.

Thereafter, after the electrolytic solution 9 inside the impregnation tank 2 is removed, as shown in FIG.
Then, as shown in FIG. 6, the capacitor element 1 is put into a liquid amount adjusting tank 10, and the amount of the electrolytic solution 9 impregnated in the capacitor element 1 by sucking air from the liquid amount adjusting tank 11 by a suction pump 11. Can be adjusted to an optimal amount to perform efficient electrolyte impregnation.

In the electrolytic solution pressurizing step shown in FIG. 4, while maintaining the raised internal pressure of the impregnation tank 2 for a certain period of time,
As in the device charging step of FIG. 1, the electrolyte supply valve 8 is closed and the electrolyte 9 is filled in the electrolyte filling unit 6 and the electrolyte pressurizing unit 7 to prepare for the next cycle. In this case, the time can be shortened, and the electrolytic solution can be impregnated with higher productivity.

Further, a plurality of different types of electrolytes are filled in a tank (not shown) and connected to each other, and these are switched to be used. It is also possible to produce

As described above, the method for manufacturing an aluminum electrolytic capacitor according to the present embodiment can impregnate the capacitor element 1 with the electrolytic solution 9 with high efficiency and accuracy, and in a very short time. This can be reduced to about 1/180 of the conventional example. Further, since the impregnation of the capacitor element 1 with the electrolytic solution 9 can be performed in a very short time, the impregnating apparatus can be extremely miniaturized, and the size can be reduced to about 1/240 of the conventional size. It is possible to realize a compact manufacturing apparatus in which manufacturing steps are connected.

The impregnation method of the electrolytic solution 9 according to the present embodiment shown in FIGS. 1 to 6 and the conventional impregnation method shown in FIGS. .2m
F, a capacitor element having a size of φ35 × L50 was manufactured, and the results of measuring the variation in electrical characteristics of the capacitor element 1 immediately after aging with respect to the capacitance, the dielectric loss (tan δ), and the leakage current are shown in Table 1. .

[0032]

[Table 1]

As is apparent from Table 1, the manufacturing method according to the present embodiment has a slightly higher capacitance than the conventional impregnation method, and further has values of dielectric loss (tan δ) and leakage current. , The electrolyte 9 was sufficiently impregnated into the inside of the capacitor element 1 in a shorter time than the conventional impregnation time, and the dispersion of electric characteristics was small, and the aluminum electrolytic capacitor of stable quality was obtained. Can be obtained.

Further, the rated voltage is 160 V, 680 μF, and the size is φ.
A capacitor element 1 of 30 × L30 was manufactured, and the result of measuring the amount of the electrolytic solution 9 impregnated inside the capacitor element 1 is shown in Table 2 below.

[0035]

[Table 2]

As is clear from Table 2, the production method according to the present embodiment is capable of adjusting the amount of the electrolytic solution 9 accurately and in a shorter time than the conventional impregnation method without variation, and impregnating it. It is possible to obtain a stable quality aluminum electrolytic capacitor.

(Embodiment 2) Hereinafter, a second embodiment of the present invention will be described with reference to FIGS. Note that the present embodiment uses the capacitor element 1 having a configuration in which a terminal plate is connected to the capacitor element used in the first embodiment, and is otherwise the same as the first embodiment. Therefore, detailed description is omitted here.

As described above, even when the capacitor element 1 having the structure in which the terminal plate is connected to the lead wire drawn from the capacitor element is used, the electrolytic solution 9 is applied to the capacitor element 1 in the same manner as in the first embodiment. Impregnation in a very short time,
In addition, the manufacturing can be performed with high accuracy, and the size of the manufacturing apparatus can be significantly reduced.

(Embodiment 3) Hereinafter, a third embodiment of the present invention will be described with reference to FIGS.
This will be described with reference to (a) and (b).

FIG. 13A shows a configuration in which an air cylinder is used as the electrolytic solution pressurizing section 7, and a speed controller 12 is provided in an air introduction path of the air cylinder to drive the piston 13. FIG. 13B shows a case where a piston 14 is used as the electrolytic solution pressurizing unit 7, and the piston 14 is driven by a servomotor 15. With such a configuration, FIG.
As shown in (a) and (b), the pressure of the electrolytic solution 9 filled in the impregnation tank 2 and the pressure rising speed are controlled by a speed controller 1.
2 and the servomotor 15 can be adjusted very easily, and even when the capacitor elements 1 of different types are impregnated with the electrolytic solution 9, the impregnation operation can be performed under optimal conditions.

[0041]

As described above, in the method for manufacturing an aluminum electrolytic capacitor of the present invention, when the capacitor element is impregnated with the electrolytic solution, the air inside the capacitor element is diluted and diffused while the pressure in the impregnation tank is reduced. By filling the inside of the tank with the electrolyte solution and immediately compressing the electrolyte solution, the pressure of the electrolyte solution is instantaneously increased, and the pressure is maintained for a certain time to impregnate the capacitor element with the electrolyte solution. By providing a step of adjusting the amount of the electrolytic solution later, variation in the amount of the electrolytic solution held by the capacitor element can be greatly reduced, and a stable quality aluminum electrolytic capacitor can be obtained.

Further, since the above-mentioned capacitor element can be impregnated with the electrolytic solution in a very short time and with high precision, it is possible to realize a great improvement in production efficiency and a reduction in the size of the equipment at the same time. It is possible to realize a compact manufacturing apparatus in which a series of manufacturing processes from a manufacturing process of a capacitor element to an assembly and an inspection process are connected.

Therefore, by increasing or decreasing the pressure or increasing or decreasing the pressure holding time for various types of capacitor elements having different materials, sizes, and shapes, it is also suitable for various types of capacitor elements. The conditions are easily determined, and the impregnation under the optimum conditions can be stably performed.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a step of inserting a capacitor element in a method for manufacturing an aluminum electrolytic capacitor according to a first embodiment of the present invention.

FIG. 2 is an explanatory view illustrating the vacuum depressurizing step.

FIG. 3 is an explanatory view showing the electrolytic solution supply step.

FIG. 4 is an explanatory view showing the electrolytic solution processing step.

FIG. 5 is an explanatory view showing the element removing step.

FIG. 6 is an explanatory view showing an electrolytic solution amount adjusting step.

FIG. 7 is an explanatory view showing an element input step of the method for manufacturing an aluminum electrolytic capacitor according to the second embodiment of the present invention.

FIG. 8 is an explanatory view showing the vacuum depressurizing step.

FIG. 9 is an explanatory view showing the electrolytic solution supply step.

FIG. 10 is an explanatory view showing the electrolytic solution processing step.

FIG. 11 is an explanatory view showing a device removing step.

FIG. 12 is an explanatory view showing an electrolytic solution amount adjusting step.

FIGS. 13A and 13B are cross-sectional views illustrating an example of an electrolyte pressurizing unit according to a third embodiment of the present invention.

14 (a), (b) are characteristic diagrams showing the state of pressurization of the electrolytic solution by the electrolytic solution pressurizing portions of FIGS. 13 (a), (b).

15A and 15B are manufacturing process diagrams illustrating a method for impregnating a capacitor element with an electrolytic solution in a conventional method for manufacturing an aluminum electrolytic capacitor.

16 (a) to 16 (c) are manufacturing process diagrams illustrating a method for impregnating another capacitor element with an electrolytic solution in a conventional method for manufacturing an aluminum electrolytic capacitor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Capacitor element 2 Impregnation tank 3 Vacuum valve 4 Sensor 5 Vacuum pump 6 Electrolyte filling part 7 Electrolyte pressurization part 8 Electrolyte supply valve 9 Electrolyte 10 Liquid amount adjustment tank 11 Suction pump 12 Speed controller 13, 14 Piston 15 Servo motor

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kiyoshi Sakamoto 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Kunihiro Nishida 1006 Kadoma, Kazuma, Osaka Pref.F-term in Matsushita Electric Industrial Co., Ltd. (Reference)

Claims (8)

[Claims] 1. A capacitor element is formed by winding an anode foil and a cathode foil provided with external lead wires with a separator interposed therebetween to form a capacitor element, and then put the capacitor element into an impregnation tank. After that, the inside of the impregnation tank was depressurized, and then the entire inside of the impregnation tank in the depressurized state was filled with the electrolytic solution, and the electrolytic solution was pressurized to impregnate the capacitor element with the electrolytic solution. The electrolytic solution in the tank is removed and the inside of the impregnation tank is returned to the atmospheric pressure.Then, the capacitor element impregnated with the electrolytic solution is taken out of the impregnation tank, and the amount of the electrolytic solution impregnated in the capacitor element is reduced to a predetermined amount. A method for manufacturing an aluminum electrolytic capacitor in which the capacitor element having been adjusted and the amount of the electrolytic solution is adjusted is inserted into a bottomed cylindrical case, and the opening of the case is sealed with a sealing member. 2. The method of manufacturing an aluminum electrolytic capacitor according to claim 1, wherein a capacitor element having a terminal plate connected to a lead wire drawn from the capacitor element is used as the capacitor element. 3. The aluminum electrolytic device according to claim 1, wherein when the electrolytic solution is impregnated into the capacitor element in the impregnation tank in a pressurized state, the electrolytic solution is heated to a liquid temperature higher than room temperature. Manufacturing method of capacitor. 4. An element assembling section for assembling a capacitor element by winding an anode foil and a cathode foil provided with external lead wires with a separator interposed therebetween, and a capacitor element having been assembled. An impregnating section for impregnating the electrolytic solution using the impregnation tank, a liquid amount adjusting section for adjusting the amount of the electrolytic solution impregnated in the capacitor element, and a capacitor element impregnated with the electrolytic solution in a bottomed cylindrical case. An aluminum electrolytic capacitor manufacturing device consisting of an assembly part that is inserted into the case and seals the opening of the case. 5. A decompression mechanism in which the impregnation section decompresses the inside of the impregnation tank, an electrolyte filling mechanism for filling the electrolyte in the impregnation tank, and an electrolyte pressurization mechanism for pressurizing the electrolyte filled in the impregnation tank. The apparatus for manufacturing an aluminum electrolytic capacitor according to claim 4, further comprising a control mechanism for controlling each of these operations. 6. The aluminum electrolytic capacitor according to claim 5, wherein an air cylinder is used as an electrolyte pressurizing mechanism, and a speed controller is provided in an air introduction path of the air cylinder to drive a piston in the cylinder. apparatus. 7. The method according to claim 5, wherein a motor drive system for driving a piston in a cylinder by a motor is used as the electrolyte pressurizing mechanism, and the piston is driven in the cylinder by using a servo motor for the motor. Manufacturing equipment for aluminum electrolytic capacitors. 8. The liquid amount adjusting section includes a holding section for individually holding the capacitor elements impregnated with the electrolytic solution, and a suction mechanism connected to the holding section.
2. A manufacturing apparatus for an aluminum electrolytic capacitor according to claim 1.