JPH0444409B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for forming an exterior body of a cylindrical solid electrolytic capacitor.

[Conventional example]

First, the structure of a cylindrical solid electrolytic capacitor will be briefly explained with reference to FIG. The capacitor 1 has a capacitor element 2 made of a sintered body of a valve metal such as tantalum, and a cathode terminal 5 in the form of a cap is connected to the cathode part 3 via an adhesive layer 4 made of solder or conductive adhesive. is fixed. Further, one end of an anode lead 6 made of a valve metal such as tantalum is embedded in the capacitor element 2, and an anode terminal 7 made of, for example, a convex metal body is welded to the other end. In this way, a capacitor assembly 10 (see FIG. 3) is obtained, and then an exterior body 8 made of synthetic resin is formed between the cathode terminal 5 and the anode terminal 7.

Conventionally, when forming the exterior body 8, a roll transfer method is used. That is, in this roll transfer method, as illustrated in FIG.
Both terminals 5,
An exterior body 8 made of resin 8a is formed between the holes 7 and 7.

[Problem that the invention seeks to solve]

However, in the roll transfer method, the coating roll 9
There is a restriction that the width of the anode lead 6 cannot be greater than the length of the anode lead 6. For this reason, it is not possible to obtain a sufficient coating film in one coat, and several coats are therefore required, resulting in poor productivity.

[Means for solving problems]

In order to solve the above-mentioned conventional drawbacks, in the present invention, a cap-shaped cathode terminal is attached to the cathode part of a capacitor element made of a valve metal sintered body through a predetermined adhesive means, and one end is connected to the capacitor element. When forming a resin exterior body on a capacitor assembly in which the anode terminal is welded and fixed to the other end of the anode lead buried in the capacitor assembly, the cathode terminal is The exterior body is formed by dropping and filling a synthetic resin liquid of a predetermined viscosity between the anode terminal and the anode terminal.

[Effect]

According to the above method, a sufficient amount of resin can be filled between the cathode terminals of the capacitor assembly without being restricted by the length of the anode lead.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to FIG. In this embodiment, the same parts as in the conventional example described above are given the same reference numerals.

In this invention, when forming the exterior body 8 on the capacitor assembly 10, a resin liquid 12 of a predetermined viscosity is filled between the cathode terminal 5 and the anode terminal 7 using, for example, a dispenser nozzle 11. .

That is, as shown in FIG. 1a, while rotating the capacitor assembly 10 about its anode lead 6 (rotation axis), a predetermined amount of resin liquid 12 is first dispensed, for example, by the dispenser nozzle 11. The resin liquid 12 is supplied to the anode terminal 7 side, and the resin liquid 12 is deposited in a heaped shape as shown in FIG. In this embodiment, the resin 12 is of an ultraviolet curing type. Next, as shown in FIG. A predetermined amount of resin liquid 12 is supplied in a heaped manner (see d in the same figure). When the capacitor assembly 10 is allowed to stand for a predetermined period of time while continuing to rotate in this state, the resin liquids 12 and 12 will adsorb each other and become familiar, forming a compact, drum-like shape as shown in FIG. Combine. After this, the resin liquid 12 is cured by irradiation with ultraviolet rays, thereby forming the exterior body 8 made of ultraviolet curable resin. The outer shape is further adjusted using the roll transfer method. That is, as shown in FIG.
A is applied and the outer shape is shaped into a substantially cylindrical shape (see g in the same figure). In addition, when attaching a color code to indicate the type of capacitor, capacitance value, etc. on the exterior body 8, as shown in FIG. The curable synthetic resin liquid 8b may be applied in a ring shape and heated.

In the above embodiment, an ultraviolet curable resin is used for the resin 12 that forms most of the exterior body 8, but the present invention is not limited to this. In addition, the order in which the same resin 12 is applied is as follows: cathode terminal 5,
It is optional whether one of the anode terminals 7 is placed first, and furthermore, two dispenser nozzles 11 may be prepared and the resin liquid 12 may be simultaneously filled into each terminal side from each of them.

〔Effect of the invention〕

As described above, according to the present invention, an exterior body made of synthetic resin can be efficiently formed between the cathode terminal and the anode terminal of a capacitor assembly, thereby achieving a significant improvement in productivity.

[Brief explanation of drawings]

Fig. 1 a to h are explanatory diagrams showing each step of this invention, Fig. 2 is a sectional view to explain the internal structure of a general cylindrical solid electrolytic capacitor, and Fig. 3 shows a conventional example. FIG. 2 is a schematic cross-sectional view. In the figure, 1 is a cylindrical solid electrolytic capacitor, 2 is a capacitor element, 3 is a cathode part, 4 is an adhesive layer, 5 is a cathode terminal, 6 is an anode lead, 7 is an anode terminal, 8 is an exterior body, 9 and 9a are 10 is a capacitor assembly, 11 is a dispenser nozzle, and 12 is a resin liquid.

Claims (1)

[Scope of Claims] 1. A cap-shaped cathode terminal is attached to the cathode portion of a capacitor element made of a valve metal sintered body through a predetermined adhesive means, and an anode lead whose one end is embedded in the capacitor element In a method of forming a resin exterior body on a capacitor assembly having an anode terminal welded and fixed to the other end, the capacitor assembly is rotated about its anode lead as an axis of rotation, and a predetermined distance is set between the cathode terminal and the anode terminal. A method for forming an exterior body of a cylindrical solid electrolytic capacitor, characterized in that the exterior body is formed by dripping and filling a viscous synthetic resin liquid. 2. The method for forming an exterior body of a cylindrical solid electrolytic capacitor according to claim 1, wherein the dropwise filling of the synthetic resin liquid is performed using a dispenser nozzle. 3. The method for forming an exterior body of a cylindrical solid electrolytic capacitor according to claim 1 or 2, wherein the synthetic resin is an ultraviolet curable resin. 4. The method for forming a casing of a cylindrical solid electrolytic capacitor according to claim 1, wherein a thermosetting resin coating film for shaping the outer shape is formed on the casing by a roll transfer method.