JPS6142849B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an electrolytic capacitor impregnation method that prevents the impregnating liquid from adhering to the lead terminals of an electrolytic capacitor element. Generally, the impregnation method for electrolytic capacitors is to connect the anode and cathode electrode foils to aluminum tabs with respective lead terminals welded to them by caulking or other methods, and then wrap the electrolytic paper around the foils to form an electrolytic capacitor element. The capacitor elements are randomly stored in impregnation boxes made of aluminum or the like, and the impregnation boxes are placed in an impregnation tank and filled with electrolyte, and the capacitor elements are impregnated with the electrolyte by applying vacuum or pressurization. However, when capacitor elements are impregnated with electrolyte using the above method, the impregnating liquid can penetrate and impregnate the capacitor elements even if the capacitor elements are stored in an impregnating box randomly or in alignment. The impregnating liquid also adheres to the surface. This adhesion of the impregnating liquid to the lead terminals may result in poor solderability of the terminals of the completed electrolytic capacitor, or may cause bending of the lead terminals during the impregnation process, which may impede the assembly work of the capacitor after impregnation. Significantly bad. Furthermore, since it cannot be connected to an automated line, it becomes a semi-automatic operation. Therefore, the disadvantage was that it was not possible to reduce the cost of the work process. The present invention eliminates the above-mentioned drawbacks and improves the impregnation method for electrolytic capacitors.It facilitates the automation of the impregnation method, greatly simplifies the process, and prevents corrosion of the lead terminals due to electrolyte adhesion. The aim is to improve quality. Hereinafter, the present invention will be explained in detail with reference to Examples. First, the anode and cathode electrode foils are welded to the respective lead terminals 1 and connected to the aluminum tabs 2 by crimping or other methods, and the electrolytic capacitor element 3, which is wound around the foils with electrolytic paper interposed therebetween, is attached to the electrode foils. As shown in Figures 1 and 2, the lead terminal 1 was continuously taped so as to be covered with an adhesive tape 4 made of crepe paper or flat paper using a natural rubber adhesive that does not react with the chemicals contained in the impregnating liquid. After, impregnation box 5
Insert by folding or rolling inside. When taping continuously, pull out lead terminal 1
It is better to make sure that the welded part between the aluminum tab 2 and the aluminum tab 2 does not protrude too much from the adhesive tape 4, or it goes inside the adhesive tape. Further, the surface of the lead terminal 1 is covered with the above-mentioned adhesive tape without any gaps by hot rolling, hot pressing, or the like. 1st
Figure A is an example in which a wide adhesive tape is used to cover almost the entire area from the welded part of the lead terminal 1 to the aluminum tab 2 to the tip, and Figure B is an example in which a wide adhesive tape is used to cover a part of the lead terminal 1 to hold it. This is an example of using narrow-width adhesive tape. Figure 3 shows an impregnating box, which is generally made of metal such as aluminum and has many holes 6 on the side and bottom to allow the impregnating liquid to easily flow in, and the shape may be arbitrary, such as a columnar shape rather than a rectangular parallelepiped. Any material that can accommodate the taped capacitor element will suffice. Next, after inserting the taped capacitor element 3 into the impregnation box 5, as shown in FIG. The liquid is poured to a level that covers the capacitor element, and impregnation is performed while controlling the liquid level of the impregnating liquid. At this time, it is preferable that the liquid surface be immersed up to the top of the capacitor element 3 and not the entire adhesive tape 4. After impregnation, the impregnation box containing the taped capacitor element 3 can be directly set in an automatic assembly machine for the next process, so that conventional semi-automatic work is no longer necessary. Since the present invention is impregnated as described above, during impregnation, the lead terminal 1 and the aluminum tab 2 are
Since the welded parts are immersed in the impregnating liquid so that they do not come in contact with the welded parts, terminal corrosion does not occur in the completed electrolytic capacitor product. In addition, poor soldering and poor contact of the lead terminal 1 due to corrosion will not occur. Since the capacitor element 3 can be impregnated with continuous taping and transferred to the next assembly process, it can be easily connected to an automated assembly line, and the lead terminal 1 will not be bent, making it easier for later assembly and inspection processes. Insertion errors almost never occur in automatic machines used in Since the capacitor elements are impregnated by being aligned in the same direction by taping, the gaps between the capacitor elements are larger than in the conventional method, and the impregnation liquid can easily flow in, so the impregnation time can be shortened and the impregnation rate can be significantly increased. The electrical characteristics of electrolytic capacitors can be significantly improved. Next, an electrolytic capacitor element having a rating of 25 WV and 100 μF was impregnated with the same impregnating liquid by the conventional method and the method of the present invention to produce electrolytic capacitors, and the results of comparison are shown in the table. Fig. 5 shows the capacitance and tan δ vs. frequency characteristics of the same capacitor.

[Table] As is clear from the table and Figure 5, the electrolytic capacitor produced by the method of the present invention has a significantly reduced defective rate in various automatic machines for assembly and inspection, and the frequency characteristics of the capacitor have also been significantly improved, as well as reducing the number of manufacturing steps. Shortened by 1/5. As described above, in the present invention, the lead terminals of the electrolytic capacitor element are held with adhesive tape, and the position of the capacitor element is kept uniform and continuous taping is performed to impregnate the element, thereby preventing the impregnating liquid from adhering to the lead terminals. This greatly reduces the cost of electrolytic capacitors, contributes significantly to lowering the defective rate and improving characteristics, and has great industrial and practical value.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a perspective view of a large number of taped capacitor elements before impregnation, and FIG. 2 is a perspective view of taped capacitor elements folded and stored in an impregnation box. Figure, 3rd
The figure is a perspective view of the impregnation box, FIG. 4 is a perspective view of a capacitor element housed in the impregnation box, and FIG. 5 is a capacitance and tan δ-frequency characteristic diagram of an electrolytic capacitor. 1: Drawer lead terminal, 2: Aluminum tab, 3: Capacitor element, 4: Adhesive tape, 5: Impregnated box.

Claims (1)

[Scope of Claims] 1. A continuous taped product in which a large number of capacitor elements are arranged in an array by holding the lead terminals of the capacitor elements with adhesive tape is stored in a folded or spiral shape in an impregnated box made of aluminum or the like. Place the impregnating box horizontally in the impregnating tank so that the capacitor element is on the bottom, and place the impregnating liquid in a position where the impregnating liquid covers the capacitor element and does not come into contact with the welded part between the pull-out lead terminal and the aluminum tab. An electrolytic capacitor impregnation method characterized by controlling the liquid level of the electrolytic capacitor. 2. The method of impregnating an electrolytic capacitor according to claim 1, wherein at least the connecting portion of the lead terminal led out from the capacitor element to the aluminum tab is held with an adhesive tape.