JP2001244143A - Capacitor housed in case - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a capacitor housed in a case, which is easy to manufacture and easily mounted, and enables an increase in density of a printed wiring board or the like and a miniaturization of the printed wiring board or the like. SOLUTION: In a capacitor 16 housed in a case of a structure, where a capacitor element 1 is housed in the case 3 and at the same time, a cover 7 having terminals 13a and 13b penetrating the cover 7 is mounted on the case 3 for sealing the element 1 in the case 3, the end, which is situated on the side of the element 1, of a terminal 14 for reinforcement is buried in the cover 7 made of an insulating resin to provide the terminal 14 on the cover 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cased capacitor.

[0002]

2. Description of the Related Art A capacitor in a case such as an aluminum electrolytic capacitor has a structure in which, for example, a capacitor element is housed in a metal or resin case, and a lid is attached to the case to seal the case. By the way, a self-supporting aluminum electrolytic capacitor or the like is used by inserting a terminal into a printed wiring board or the like and fixing it by soldering or the like. For this reason, the lid 20 has a structure as shown in FIG. 2, for example. That is, the bakelite 21 is made of rubber 22 such as EPT.
Is used. Then, the anode terminal 23 and the cathode terminal 24 are provided to penetrate the lid 20. Further, in order to firmly fix the capacitor 25 to the printed wiring board and improve vibration resistance, a reinforcing terminal 27 not connected to the capacitor element 26 is provided through the lid 20. The lid 20 is attached to the case 28 and hermetically seals it. A thin explosion-proof mechanism 2 is provided on the bottom of the case 28.
9 are provided. The case 28 is covered with an insulating tube 30.

[0003]

However, the conventional lid 20
In the structure of (1), the capacitor element 26 is housed in the case 28, and when the lid 20 is attached to the case 28, the lead wire 31 pulled out from the capacitor element 26 is arranged in contact with the reinforcing terminal 27 on the way. Sometimes. The reinforcing terminal 27 is usually a cathode, but has the polarity of the anode when the lead wire 31 contacts. For this reason, when using a self-standing substrate type aluminum electrolytic capacitor or the like connected to a printed wiring board or the like, it is necessary to design a place where the reinforcing terminal 27 is connected to be sufficiently insulated from other circuits.
There is a disadvantage that it is difficult to increase the density and reduce the size of the printed wiring board.
Further, in the conventional capacitor 25, since the end of the reinforcing terminal 27 is also drawn out from the bakelite 21 side of the lid 20, the lead wire 31 of the capacitor element 26 is formed.
Must not contact the reinforcing terminal 27,
It has the disadvantage that it is very difficult to manufacture. Further, the end of the reinforcing terminal 27 may be covered with an insulating sheet.
It also has the disadvantage of being difficult to manufacture.

An object of the present invention is to provide a capacitor in a case which improves the above-mentioned drawbacks, is easy to manufacture, and can be mounted on a printed circuit board or the like with high density and small size. .

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a capacitor in a case, in which a capacitor element is housed in a case, and a lid having a penetrating terminal is attached to the case and hermetically sealed. The reinforcing terminal is provided by embedding the end on the capacitor element side in the lid made of insulating resin.

That is, according to the present invention, since the end of the reinforcing terminal on the capacitor element side is embedded in the lid,
It is possible to completely prevent the capacitor element from contacting the reinforcing terminal without the end of the reinforcing terminal protruding into the case. Therefore, when the capacitor element is housed in the case and the lid is attached to the case, the lead wire drawn out of the capacitor element is arranged so as not to contact the end of the reinforcing terminal, or the insulating sheet is coated on the end. This makes it easier to manufacture the capacitor without the necessity of performing any processing such as slipping. Also,
Since the reinforcing terminals are completely insulated, there is no need to use an insulating structure around the reinforcing terminals when the capacitor is connected to a printed wiring board, etc., making it possible to increase the density and size of the printed wiring board. Become.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 1 denotes a capacitor element. This capacitor element 1 has a structure in which an anode foil and a cathode foil are laminated via electrolytic paper, wound, and an anode lead wire 2a and a cathode lead wire 2b are drawn out. The anode foil is formed by forming an oxide film on a valve metal foil such as an etched high-purity aluminum foil and connecting the anode lead wire 2a. As the cathode foil, one obtained by connecting a cathode lead wire 2b to a valve action metal foil such as an etched aluminum foil is used. Manila paper or kraft paper is used as the electrolytic paper. The capacitor element 1 may have a structure in which the cathode foil protrudes from the bottom surface of the anode lead wire 2a or the like opposite to the drawing direction, and the protruded cathode foil contacts the inner bottom surface of the case 3, thereby providing heat dissipation. The effect can be improved, and the allowable ripple current can be increased. Further, as the capacitor element 1, a metallized paper or a metallized film obtained by vacuum-depositing zinc or the like on a capacitor paper or a plastic film is wound, and a metallikon is provided on both end faces, and a lead wire is connected to the metallikon. May be used.

[0008] The case 3 is made of a metal material such as aluminum.
It is formed in a cylindrical shape in appearance. The bottom 4 of the case 3 has a thick peripheral portion 5a with a protruding edge portion 5a, and a groove-shaped explosion-proof mechanism 6 is provided at the center portion 5b. The peripheral portion 5a and the central portion 5b do not have a step on the inner surface side. By contacting the bottom surface of the capacitor element 1 with these, the heat dissipation is superior to the case where there is a step.

Reference numeral 7 denotes a lid, made of an insulating resin such as polyphenylene sulfide or phenol, and having a thickness of 3 mm to 10 mm.
It has a thickness of about mm and is placed on a protrusion 9 provided on the inner peripheral surface near the square 8 of the case 3, and is mounted on the case 3 by curling the square 8. The peripheral portion 10 of the lid 7 has a small thickness and forms a step with respect to the central portion, a projection 11 having a triangular cross section is provided, and an elastic band 12 made of an elastic material such as rubber is arranged. The bent end of the bent square 8 of the case 4 is inserted into the elastic band 12 to improve the sealing performance. The lid 7 has an anode terminal 13a.
And the cathode terminal 13b. The anode lead 2a is connected to the anode terminal 13a by riveting or ultrasonic welding, and the cathode lead 2b is connected to the cathode terminal 13b by a similar method. Further, a reinforcing terminal 14 is provided on the lid 7. The reinforcing terminal 14 has one end 15a protruding out of the case 3 to the same height as the anode terminal 13a and the cathode terminal 13b, but the other end 15b of the capacitor element 1 is embedded in the lid 7 and is inserted into the case 3. Does not protrude. The reinforcing terminal 14
May be provided not only one but also two or more. In particular,
When the diameter of the capacitor is large, the larger the number, the better the vibration resistance. The case 3 is covered with an insulating tube 16.

Next, a method of manufacturing the above-described cased capacitor 17 will be described. First, an anode lead wire 2a is connected to an anode foil having an oxide film formed by subjecting a valve metal such as aluminum to an etching treatment and anodizing treatment by a cold welding method, a caulking method, or the like. Further, a cathode lead wire 2b is connected to the cathode foil by a cold welding method or the like. Then, the anode foil and the cathode foil are overlapped and wound via an electrolytic paper to form the capacitor element 1. Next, the capacitor element 1 is impregnated with an electrolytic solution by a vacuum impregnation method, a vacuum pressure impregnation method, or the like. Also, the anode terminal 13a and the cathode terminal 13
Both ends of b and one end of the reinforcing terminal 14 are pulled out, molded by resin, and the elastic band 12 is fitted thereon to form the lid 7. Further, the case 3 is manufactured by molding an aluminum plate or the like into a mold. Then, the anode lead 2a and the cathode lead 2b drawn from the capacitor element 1 are connected to the anode terminal 13a and the cathode terminal 13b, respectively, so that the capacitor element 1 and the lid 7 are integrated. After this, the capacitor element 1
Is stored in the case 3, the square 8 of the case 3 is curled, the lid 7 is attached to the case 3, and the case 8 is sealed. After sealing, aging is performed by applying a voltage higher than the rated voltage while gradually increasing the pressure in a high-temperature atmosphere.

[0011]

As described above, according to the present invention, in a capacitor in a case in which a capacitor element is housed in a case and a lid having a penetrating terminal is attached to the case and hermetically sealed, Since the reinforcing terminals are provided by embedding the ends on the side of the capacitor element, a cased capacitor can be obtained which can be easily manufactured and which can be mounted with a high density and compact printed wiring board. And because the lid is made of insulating resin,
Ripple resistance can be improved, and when used in inverter circuits, etc., many capacitors were conventionally connected and used.However, the number of connected capacitors can be reduced, making connection work easier,
A capacitor in a case can be obtained in which a device incorporating the circuit can be miniaturized.

[Brief description of the drawings]

FIG. 1 shows a sectional view of an embodiment of the present invention.

FIG. 2 shows a cross-sectional view of a conventional cased capacitor.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Capacitor element 3 ... Case 7 ... Lid 13a
... Anode terminal, 13b ... Cathode terminal, 14 ... Reinforcing terminal,
17… Capacitor in case. Reference number P2532

Claims (1)

[Claims] 1. A capacitor in a case in which a capacitor element is housed in a case and a lid having a penetrating terminal is attached to the case and hermetically sealed, and an end of the capacitor element side is buried in the lid made of insulating resin to reinforce the capacitor. A case-containing capacitor characterized by providing terminals for use.