JP2679564B2 - Film capacitor exterior method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film capacitor used in electronic equipment and electric equipment.

[0002]

2. Description of the Related Art In recent years, film capacitors have been widely used in the fields of consumer and industrial equipment, and also in the field of space because of their excellent performance such as low loss and stable temperature characteristics and high reliability. However, with the recent trend toward smaller and lighter equipment, there is a strong demand for smaller and lighter film capacitors and higher reliability.

A film capacitor is composed of a film capacitor element obtained by winding or laminating a dielectric film and an electrode, and an exterior body for the purpose of improving electrical / mechanical protection and weather resistance of the film capacitor element. The film capacitor element itself must be miniaturized in order to realize a small size and light weight, but the exterior is simplified,
Weight reduction is just as important.

A conventional method for packaging a film capacitor will be described below. The film capacitor packaging methods are roughly classified into case packaging and resin coating packaging.
The resin coating has a problem of mechanical strength and dimensional accuracy and a problem of attachment to a substrate, and thus the packaging of a large capacitor is generally a case packaging.

FIG. 2 shows the structure of a conventional film capacitor having a case exterior, in which a film capacitor element 5 to which a lead terminal 6 is connected is housed in a box-shaped case 9 and thereafter, A film capacitor is formed by injecting the filling resin 8 and solidifying the filling resin 8 to form an exterior.

[0006]

However, in the above-mentioned packaging method, since the cross section of the film capacitor element is usually oval or round, an excessive amount of filling resin is filled below and above the case. Has a drawback that the resin becomes large and heavy, and in the thermal shock test, cracks occur in the filled resin due to expansion and contraction of the outer case.

In order to solve this problem, as shown in FIG. 3, there is a method in which the case shape is matched with the shape of the film capacitor element 5 and the film capacitor element is housed in the vertical direction. The longer the contact terminals, the larger the loss, and the problems of performance degradation and filling resin cracks cannot be solved.

There are other tape packaging methods and resin molding packaging methods other than the above, which are effective in terms of downsizing and weight reduction, but the tape packaging is inferior in mechanical strength and weather resistance. In addition, the resin mold exterior has problems such as lead terminal disconnection due to high pressure during molding, and the fact that the molding machine and molding die are expensive, both of which are compact, lightweight and highly reliable. Both were not possible exterior methods.

The present invention solves the above-mentioned conventional problems, and an object thereof is to provide a compact, lightweight and highly reliable film capacitor packaging method.

[0010]

In order to achieve this object, a method of packaging a film capacitor according to the present invention comprises a set of cylinders each having a continuous elongated kerf in the longitudinal direction. A film capacitor element to which a lead terminal is connected is housed, an outer case is joined with a filling resin, and then the filling resin is injected from the cut groove portion and solidified.

[0011]

According to this packaging method, by using a cylinder having a round or oval cross-sectional shape according to the cross-sectional shape of the film capacitor element to be housed as the packaging case, the amount of resin to be filled is greatly reduced. Further, the thickness of the outer package is substantially uniform around the film capacitor element, stress concentration at the time of thermal shock is relieved, and thermal shock resistance can be improved.

Further, by using the filling resin as the adhesive material of the joint portion, there is no stress of expansion and contraction of the outer case which is one cause of the cracking of the filling resin. In addition, the material of the cylinder and the filling resin can be used as the case exterior material, which has a proven record of mechanical strength, weather resistance, and other performance and reliability. A high film capacitor can be obtained.

[0013]

An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1A, a male part 1 and a female part 3
A pair of cylinders each having an open end on one side and provided with a kerf 7 in the longitudinal direction.
The film capacitor element 5 connected to is inserted from the open portion of each cylinder. At that time, the lead terminal 6 is housed while passing through the cut groove portion 7. After the thermosetting filling resin is applied to the male part joining surface 2 and the female part joining surface 4 and joined and heat-treated, the kerf 7
Further, the same thermosetting filling resin 8 as the resin used for joining the joining surfaces is injected into the cylinder and thermoset to obtain a film capacitor.

The film capacitor formed as described above can be reduced in volume and weight by about 20 to 30% as compared with the conventional case exterior product shown in FIG.

In this embodiment, the film capacitor element has a round cross-sectional shape. However, even if an oval element is used, the tubular cross-sectional shape can be changed to an oval shape according to the shape of the element. The same effect can be obtained and the present invention is not limited thereto.

[0017]

As described above, the present invention provides a film capacitor element in which a lead terminal is connected to the inside of a set of cylinders each having a continuous elongated kerf in the longitudinal direction and one end of which is open. The lead terminals are housed by inserting them into the cut grooves of each cylinder, one side at a time, and then the film capacitor element is packaged by a method of injecting a filling resin from the cut groove portions and solidifying it. Moreover, a film capacitor with high reliability can be realized.

[Brief description of the drawings]

1A is a perspective view of a film capacitor according to an embodiment of the present invention, FIG. 1B is a side sectional view of a film capacitor according to an embodiment of the present invention, and FIG. 1C is a sectional view taken along line AA ′ of FIG. 1B.

FIG. 2A is a side sectional view of a conventional film capacitor, and FIG. 2B is a sectional view taken along the line A-A ′ in FIG.

FIG. 3 (a) is a side sectional view of a film capacitor considered to solve the problem (b) a top view of (a)

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Male part 2 Male part joint surface 3 Female part 4 Female part joint surface 5 Film capacitor element 6 Lead terminal 7 Cut groove part 8 Filling resin 9 Box case

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Shunsuke Ono 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) Reference JP-A-4-338618 (JP, A) JP-A-61- 84012 (JP, A)

Claims (1)

(57) [Claims] 1. A film capacitor element having a lead terminal connected to the inside of a set of cylinders, each having a continuous elongated slit in the longitudinal direction and having an open end on one side. A method for packaging a film condensate, in which each tube is housed by being inserted through the cut groove portions of the respective cylinders, the outer case is joined by using a filling resin, and then the filling resin is injected from the cut groove portions and solidified.