JPS6226167B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a chip type capacitor, and more particularly to an improvement in the structure of a chip type solid electrolytic capacitor.

In general, chip-type solid electrolytic capacitors, for example, as shown in FIG. 1, are made by press-molding and sintering tantalum metal powder having a valve action, and forming a capacitor element 1 with a tantalum wire as an anode lead 2 in advance.
The first plate-shaped metal terminal 3 is welded to the protruding portion of the anode lead 2, and the second plate-shaped metal terminal 4 is attached to the circumferential surface of the capacitor element 1 with a dielectric oxide film layer 5 and a semiconductor layer. The capacitor element 1 is connected to the cathode electrode extraction layer 7 formed through the capacitor element 6, and the entire circumferential surface of the capacitor element 1 is covered with an exterior resin material 8, and then the second
As shown in the figure and Fig. 3, plate metal terminals 3, 4
In the process of bending at the bending points 3a, 3b, 4a, and 4b, as shown in Fig. 2, first the capacitor body (hereinafter referred to as the body) of the plate metal terminals 3 and 4 is folded.
Bend points 3a and 4a at the base protruding from 9
are bent along the left and right side surfaces 9a of the main body 9, and then the bent portions 3b and 4b at the tip are bent along the bottom surface 9b of the main body 9.
For this reason, as shown in FIG.
The inner angles of the bending points 3a, 3b and 4a, 4b of 4 are larger than the inner angles during the bending process shown in FIG.
4 can no longer maintain parallel and close contact with the side surfaces 9a and bottom surface 9b of the main body 9, and the side surfaces 9a and bottom surface 9
I had drifted away from b.

For this reason, it had the following drawbacks.

(a) The height and longitudinal dimensions of the capacitor become large, resulting in poor volumetric efficiency when mounted on a printed wiring board.

(b) The capacitor does not sit well when mounted on the printed wiring board.

(c) When performing temporary fixing work with adhesive before soldering and mounting on a printed wiring board, the adhesive must be applied thickly to the bottom of the capacitor.

It is an object of the present invention to provide a chip type capacitor which eliminates such conventional drawbacks.

According to the present invention, in a chip-type capacitor having a resin-sheathed capacitor body and a plate-shaped metal terminal led out from the body and formed by bending a plurality of places along the outer surface of the body, the plate-shaped A chip-type capacitor is obtained, which is characterized in that a tapered notch is formed on at least one surface of the outer surface of the main body along which the metal terminal extends, the taper-shaped notch becoming deeper toward the tip of the metal terminal.

Embodiments of the present invention will be described below with reference to FIGS. 4 to 8.

FIG. 4 is a front view showing the state before the plate metal terminals 3 and 4 of the chip type capacitor according to the first embodiment of the present invention are bent. A tapered notch 9c having an angle of A with respect to the other end is formed. The angle A of this notch 9c is determined by the bending points 3a and 3b or 4a of the plate metal terminals 3 and 4 shown in FIG.
and 4b, and are formed in opposite directions.

FIG. 5 shows the condition during bending of the plate-shaped metal terminals 3 and 4 of a chip-type capacitor in which tapered notches 9c are formed at both ends of the bottom surface of the main body 9 as described above. Metal terminals 3, 4
along the side surface 9a of the main body 9 at the bending point 3a,
4a, and then the bottom part 9 of the main body 9.
A bending process is performed at the bending points 3b and 4b along the surface of the tapered notch 9c formed at both ends of b.

The plate metal terminals 3 and 4 which have been bent in this way have bent portions 3a, 3b and 4.
Spring back occurs at the bending points 3a, 3 and 4a, 4 as shown in FIG.
The interior angle b is larger than the interior angle during the bending process shown in FIG. However, as shown in FIG.
Since a tapered notch 9c is formed with an angle A approximately equal to the sum of the springback angles a and 4b, the bending point 3 is formed as shown in FIG.
b and 4b are bent more by an angle A shown in FIG. 4 than the plate-shaped metal terminal of the conventional structure. Therefore, as shown in FIG. 6, after the bending process, the mounting surfaces 3c and 4c of the plate metal terminals 3 and 4 are
The main body 9 is formed so as to be substantially parallel to the bottom surface 9 of the main body 9 and substantially in contact with an extended surface of the bottom surface 9b of the main body 9.

Next, a second embodiment of the present invention is shown in FIGS. 7 and 8.
This will be explained using figures.

FIG. 7 is a diagram showing the state before bending of the plate-shaped metal terminal of a chip-type capacitor according to the second embodiment of the present invention, and shows both sides of the main body 9 molded in the same manner as in FIG. 4 of the first embodiment. A tapered notch 9a having an angle B is formed at the lower end of the surface 9a. The angle B of this tapered notch 9d is the bending point 3a, 4a of the plate metal terminal 3, 4 shown in FIG.
The angle is approximately equal to the springback angle of the spring.

FIG. 8 shows the state after the plate metal terminals 3 and 4 of the chip type capacitor having the body 9 molded in this manner are successively bent in the same manner as in the first embodiment.
The plate metal terminals 3 and 4 that have been bent are
Spring back occurs at the bending points 3a, 4a, and the side surfaces 3d, 4d of the plate metal terminals 3, 4 become almost parallel to the side surface 9a of the main body 9, and almost touch the extended surface of the side surface 9a of the main body 9. It is formed. The plate metal terminals 3 and 4 used in the first and second embodiments of the present invention are the same in shape, size, and material.

As described above, the present invention allows the plate-shaped metal terminals protruding from the side surfaces of the capacitor to be bent while maintaining the bottom surface or the bottom surface and the side surfaces of the capacitor body in a substantially parallel state. The longitudinal dimension is reduced, and the volume efficiency and area efficiency when mounted on a printed wiring board are improved.

(ii) Improved seating when mounting the capacitor on the board.

(iii) The thickness of the adhesive used to temporarily fasten the capacitor during board mounting can be reduced.

It has the following effects, and its industrial value is enormous.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a conventional chip-type capacitor, and FIGS. 2 and 3 are front views of the conventional chip-type capacitor during and after bending a plate-shaped metal terminal. FIG. 4 is a front view of the chip-type capacitor according to the first embodiment of the present invention before bending the plate metal terminal. 5 and 6 are front views of a plate-shaped metal terminal of a chip-type capacitor according to the first embodiment of the present invention during and after bending. FIG. 7 is a front view of a chip-type capacitor according to a second embodiment of the present invention before bending a plate-shaped metal terminal. FIG. 8 is a front view of a chip-type capacitor according to a second embodiment of the present invention after the plate-shaped metal terminal is bent. 1... Capacitor element, 2... Anode lead,
3, 4...first and second plate metal terminals, 3a, 3
b, 4a, 4b...bending points of the first and second plate metal terminals, 3C, 4C...mounting surfaces of the first and second plate metal terminals, 3d, 4d...first and second side surface of the plate-shaped metal terminal, 5...dielectric oxide film layer,
6... Semiconductor layer, 7... Cathode electrode extraction layer, 8
... Exterior resin material, 9 ... (chip type capacitor)
Main body, 9a...Side surface of the main body, 9b...Bottom surface of the main body, 9c...Tapered notch (on the bottom of the main body), 9d...Tapered notch (on the side of the main body), A... Angle of the notch (on the bottom of the main body), B...
...The angle of the notch (on the side of the main body).

Claims (1)

[Claims] 1. A chip-type capacitor having a resin-sheathed capacitor body and a plate-shaped metal terminal extending from the body and formed by bending two places along the outer surface of the body, the body along which the plate-shaped metal terminal runs along. 1. A chip-type capacitor, characterized in that a tapered notch is formed on at least the bottom surface of the outer surface of the plate-shaped metal terminal so that it becomes deeper toward the tip.