JPH0311882Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] This invention relates to solid electrolytic capacitors, and in particular, to prevent undesired exposure of external lead members connected to the electrode lead layer of a capacitor element from a resin material. It concerns the lead structure.

[Prior art]

Generally, this type of solid electrolytic capacitor is
As shown in the figure, a metal wire having a valve action is attached in advance to a capacitor element A which is formed by press-forming metal powder having a valve action into a prismatic shape and sintering it, and an anode lead B.
A plate-shaped first external lead member C is welded to this anode lead B, and a plate-shaped second external lead member C is welded to the anode lead B.
The external lead member D is connected to the electrode lead layer E formed on the circumferential surface of the capacitor element A via an oxide layer and a semiconductor layer using a conductive adhesive F, and the entire circumferential surface of the capacitor element A is covered with resin. It is constructed by mold-covering with material G.

By the way, the second external lead member D is connected to the electrode lead layer E by the conductive adhesive F applied to the inner end portion, but when making the connection, for example, a capacitor element If A is eccentric with respect to the anode lead B, or if the anode lead B is deformed, the end of the second external lead member D is pushed by the capacitor element A and deforms as shown by the dotted line in the figure. However, it is exposed from the resin material G. For this reason, not only the appearance but also the moisture resistance is impaired.

[Problem that the invention attempts to solve]

Therefore, as shown in Utility Application No. 1987-872, the present applicant has previously installed the capacitor elements mounted on the first and second external lead members of the lead frame into the upper mold and the lower mold. The first and second external lead members are housed in a cavity formed of a mold, and the first and second external lead members are placed on the parting surfaces of the bottom mold and the bottom mold by a protrusion formed on the upper inner surface of the bottom mold. We have proposed a solid electrolytic capacitor constructed by sandwiching the second external lead member so that the outward positional shift is corrected, and then injecting a resin material into the cavity.

According to this proposal, even if the second external lead member is deformed when connecting the anode lead of the capacitor element to the first external lead member, the protrusion of the upper mold forcibly corrects the deformation. Although it is possible to reliably prevent the second external lead member from being exposed from the resin material, the hole formed in the resin material by the protruding part of the upper mold is a separate process from the viewpoint of appearance and moisture resistance. There is a problem in that workability is impaired because the area must be closed.

Therefore, an object of the present invention is to provide a solid electrolytic capacitor that has a simple structure and can completely eliminate exposure of the external lead member from the resin material without impairing workability.

[Means to solve the problem]

Therefore, in order to achieve the above-mentioned purpose, the present proposal:
An electrode lead layer is formed on the circumferential surface of a capacitor element made of a metal member having a valve action, from which a metal wire having a valve action is led out as an anode lead, and a plate-shaped layer is formed from the anode lead and the electrode lead layer. The first and second external lead members are led out, and the main part including the capacitor element is molded and covered with a resin material, and an L-shaped bent part is formed at the inner end portion of the second external lead member. At the same time, a concave portion into which a capacitor element is inserted is formed in this bent portion, the width of which is sequentially increased from the lead-out side to the non-lead-out side of the anode lead.

[Effect]

According to this invention, the capacitor elements, which are successively formed in width, are inserted into the recess of the bent part of the second external lead member from the outlet side (narrow width part) of the anode lead, and the second external lead member upon connection of the anode lead to the first external lead member in an electrically connected and mechanically rigidly bonded relationship. Even if the lead member is pushed by the capacitor element, the deformation will not expand much because the deformed portion is integrated with the capacitor element.
Therefore, exposure of the second external lead member from the resin material can also be prevented.

〔Example〕

Next, an embodiment of the present invention will be described with reference to FIGS. 1 and 2.

In the figure, reference numeral 1 denotes a capacitor element formed by press-forming metal powder having a valve action into a prismatic shape and sintering it. A wire is installed as an anode lead 2. The capacitor element 1 is formed so as to become wider in order from the lead-out side of the anode lead 2 toward the non-lead-out side. Then, an oxide layer is formed on the circumferential surface of the capacitor element 1.
An electrode lead layer 3 is formed with a semiconductor layer interposed therebetween. On the other hand, a plate-shaped first external lead member 4 is welded to the anode lead 2, and a plate-shaped second external lead member 5 is connected to the electrode lead layer 3. An L-shaped bent portion 6 is formed at the inner end portion of the second external lead member 5, and a U-shaped recessed portion 7 is formed in the bent portion 6. Capacitor elements 1, which are sequentially formed to have wider widths, are inserted into this recess 7 from the lead-out side (narrow part) of the anode lead and moved to the non-lead side (wider part), thereby engaging the capacitor elements 1. electrically and mechanically connected. At this time, a conductive adhesive 8 can also be used. The entire circumferential surface of the capacitor element 1 is coated with a resin material 9 by molding. First and second external lead members 4 and 5 derived from this resin material 9
are bent along the side and bottom surfaces of the resin material 9.

[Effect of idea]

As described above, according to the present invention, the capacitor elements formed to have wider widths are inserted into the second external lead member from the lead-out side (narrow width part) of the anode lead into the recessed part of the second outer lead member, and the capacitor elements are successively formed to have wider widths. When the anode lead is welded to the first external lead member, the second Even when the external lead member is pushed by the capacitor element, the amount of deformation is not increased because it is deformed integrally with the capacitor element. Therefore, it is possible to prevent the second external lead member from being exposed from the resin material.

In addition, in this way, the capacitor elements, which are successively formed in width, can be inserted into the recess from the narrow part and then moved to the wide part for engagement. In addition to improving the engagement state, deformation of the second external lead member during welding of the anode lead to the first external lead member can be suppressed.

In the present invention, the capacitor element may have a cylindrical shape as well as a prismatic shape. or,
The recessed portion of the second external lead member can be appropriately formed into a rectangular shape, a semicircular shape, etc. depending on the outer shape of the capacitor element.

[Brief explanation of the drawing]

Figure 1 is a front sectional view showing one embodiment of the present invention, Figure 2
The figure is a perspective view showing an exploded state, and FIG. 3 is a front sectional view of a conventional example. In the figure, 1... Capacitor element, 2... Anode lead, 3... Electrode lead layer, 4... First external lead member, 5... Second external lead member, 6
. . . bent portion, 7 . . . recessed portion, 9 . . . resin material.

Claims (1)

[Claims for Utility Model Registration] (1) Forming an electrode lead layer on the circumferential surface of a capacitor element made of a metal member having a valve action, from which a metal wire having a valve action is led out as an anode lead. The plate-shaped first and second external lead members are led out from the anode lead and electrode lead-out layer, and the main parts including the capacitor element are molded and covered with a resin material, wherein the second external lead member is An L-shaped bent portion is formed at the inner end portion of the anode lead, and a recess into which the capacitor element is inserted is formed in the bent portion, the width of which is sequentially widened from the lead-out side to the non-lead-out side of the anode lead. A solid electrolytic capacitor featuring: (2) Utility model registration claim 1, characterized in that the capacitor element is fitted into the recess of the second external lead member and electrically and mechanically connected.
Solid electrolytic capacitors as described in section.