JPH11145000A - Vertical chip-type aluminum electrolytic capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vertical chip-type aluminum electrolytic capacitor in which contact between an external bottom surface of a case and a pair of lead and that between the external bottom surface of the case and a wiring pattern of a printed board are prevented, for stabilized product characteristics. SOLUTION: An external bottom surface 21a of a bottomed cylindrical case 21 which is, sealed with an opening part with a lid member 25, incorporated with a capacitor element 22 comprising a pair of leads 24 together with a driving electrolyte is coated or painted with an insulating material 26, while the pair of leads 24 led outside through a pair of through-holes 23 provided at a bottom part of the case 21 are bent along the external bottom surface 21a of the case 21, on which the insulating material 26 is coated or painted, which is a mounting surface to a printed board.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vertical chip type aluminum electrolytic capacitor used for various electronic devices and surface-mounted on a printed circuit board.

[0002]

2. Description of the Related Art In recent years, in response to demands for downsizing and high-density mounting of electronic components used in various electronic devices, surface mounting components have been widely used in industry. In the case of a capacitor, in such a flow, as one example, a conventional radial type aluminum electrolytic capacitor is applied to form a chip shape that can be surface-mounted on a printed circuit board, that is, as shown in FIGS. The capacitor element 1 and the driving electrolyte are both housed in a bottomed cylindrical case 2 made of aluminum, and a pair of lead wires 3 provided on the capacitor element 1 are provided.
Is drawn out from the opening side of the case 2 through the sealing body 4 provided in the opening of the case 2, and the case 2 is drawn and sealed to perform sealing.
A square insulated terminal plate 5 on the sealing surface of
An external structure that can be surface-mounted on a printed circuit board by passing a pair of lead wires 3 penetrating the sealing body 4 through the insulating terminal plate 5 and then bending the pair of lead wires 3 along the insulating terminal plate surface 5a. A vertical chip type aluminum electrolytic capacitor has been proposed.

The conventional vertical chip type aluminum electrolytic capacitors shown in FIGS. 5 and 6 employ a radial type aluminum electrolytic capacitor. Therefore, in order to reduce the product height, a radial type aluminum electrolytic capacitor is required. Although it is necessary to reduce the height of the capacitor itself, the conventional radial type aluminum electrolytic capacitor has a rubber opening formed in the case 2 for housing the capacitor element 1 in order to prevent leakage and diffusion of the driving electrolyte to the outside. Since the structure is such that the sealing is performed by the sealing member 4 made of a rubber-like elastic body, if the height of the product is reduced as it is, the space for securing the amount of the driving electrolyte decreases, and the thickness of the sealing member 4 also decreases. Therefore, the permeation of the driving electrolyte increases,
The problem is that the life of the capacitor characteristics is greatly affected.

Further, when the thickness of the sealing body 4 is reduced, the sealing strength is also weakened. Therefore, when the pressure inside the capacitor increases when solder reflow is performed during surface mounting on a printed circuit board, the sealing body 4 expands, and This sealing body 4
Since the swelling affects the mounting stability on a printed circuit board and the sealing property, securing the sealing strength has been a major issue.

In order to solve the above-mentioned problems, the present inventors can reduce the height of the product by eliminating the thickness of the sealing body which is required in the conventional structure, and can reduce the height of the sealing body. The life of the capacitor can be extended by drastically reducing the amount of surface permeation of the driving electrolyte.
Furthermore, by increasing the strength of the exterior body, it is possible to ensure sufficient mounting stability and sealing performance during surface mounting on a printed circuit board by solder reflow, and furthermore, utilizing the conventionally used capacitor element, and We have developed a vertical chip type aluminum electrolytic capacitor that can be obtained inexpensively by using a structure that requires less material for the sealing body.

That is, as shown in FIGS. 7 and 8, a pair of through holes 13 are provided at the bottom of a bottomed cylindrical case 11 in which a capacitor element is incorporated together with a driving electrolyte. The pair of lead wires 14 provided in the capacitor element 12 is penetrated and drawn out, and the gap between the pair of through holes 13 and the pair of lead wires 14 is sealed by a sealing body 17, and the bottomed cylindrical shape is formed. A vertical chip type aluminum electrolytic capacitor having a configuration in which the opening of the case 11 is sealed with a lid member 15 and a pair of lead wires 14 drawn out to the outside are bent along the outer bottom surface 11a of the case 11 has been developed. .

[0007]

However, the vertical chip type aluminum electrolytic capacitor having the structure shown in FIGS. 7 and 8 has a pair of through holes 13 formed in the bottom of a cylindrical case 11 having a bottom. Since the pair of lead wires 14 provided in 12 is penetrated and drawn out, and the pair of lead wires 14 drawn out is bent along the outer bottom surface 11a of the case 11 to form a mounting surface on a printed circuit board. When the case 11 is made of a conductive material such as a metal, contact between the outer bottom surface 11a of the case 11 and the pair of lead wires 14 bent along the outer bottom surface 11a,
Alternatively, there is a problem that a short circuit occurs due to contact between the outer bottom surface 11a of the case 11 and the wiring pattern of the printed circuit board.

The present invention has been made to solve the above problems, and can prevent contact between the outer bottom surface of a case and a pair of lead wires and contact between the outer bottom surface of a case and a wiring pattern of a printed circuit board. It is an object of the present invention to provide a vertical chip type aluminum electrolytic capacitor capable of stabilizing product characteristics.

[0009]

In order to achieve the above object, a vertical chip type aluminum electrolytic capacitor of the present invention has a bottomed cylindrical case in which a capacitor element having a pair of lead wires is built in together with a driving electrolyte. And a pair of through holes provided at the bottom of the case and through which a pair of lead wires of the capacitor element penetrate and are drawn out of the case, and sealing a gap between the pair of through holes and the pair of lead wires. It has a pair of sealing bodies and a lid member for sealing the opening of the bottomed cylindrical case, and coated or coated with an insulating material on the outer bottom surface of the case, and was pulled out of the case. A pair of lead wires are bent along the outer bottom surface of the case coated or coated with an insulating material to form a mounting surface on a printed circuit board. It is possible to prevent the contact between the outer bottom and the printed circuit board wiring pattern of contact and the case of the lead wire, thereby, in which stabilization of the product characteristics can be achieved.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An invention according to claim 1 of the present invention is a bottomed cylindrical case in which a capacitor element having a pair of lead wires is built in together with a driving electrolyte, and is provided at the bottom of the case. A pair of through holes through which a pair of lead wires of the capacitor element penetrates and is drawn out of the case; a pair of sealing bodies for sealing a gap between the pair of through holes and the pair of lead wires; A lid member for sealing an opening of the cylindrical case, and coating or applying an insulating material to an outer bottom surface of the case, and coating the pair of lead wires drawn out of the case with the insulating material. Alternatively, the case is bent along the outer bottom surface of the applied case to form a mounting surface on a printed circuit board. According to this configuration, even when the case is formed of a conductive material such as metal, The contact between the bottom surface and a pair of lead wires and the contact between the outer bottom surface of the case and the wiring pattern of the printed circuit board can be reliably prevented by the insulating material coated or applied to the outer bottom surface, thereby preventing the occurrence of short circuit. Therefore, the product characteristics can be stabilized.

According to a second aspect of the present invention, the case in which the capacitor element is incorporated together with the driving electrolyte is formed in a rectangular tube having a bottom, and according to this configuration, the case is occupied by the conventional square insulated terminal plate. Since the mounting space can be maximized, the amount of the driving electrolyte contained in the case that constitutes the external body of the capacitor can be significantly increased, which further extends the life of the capacitor characteristics. It can be planned.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. (Embodiment 1) FIG. 1 is a perspective view of a vertical chip type aluminum electrolytic capacitor according to Embodiment 1 of the present invention.
FIG. 2 is a longitudinal sectional view of the capacitor. In FIGS. 1 and 2, reference numeral 21 denotes a case made of aluminum having a bottomed cylindrical shape, and a capacitor element 22 is built in the case 21 together with a driving electrolyte. A pair of through-holes 23 are provided at the bottom of the case 21, and a pair of lead wires 24 provided in the capacitor element 22 are passed through the pair of through-holes 23 and drawn out to the outside. Is sealed by a lid member 25 made of aluminum, and an outer bottom surface 21a of the case 21 is coated or coated with a heat-resistant insulating material 26 such as a resin.

A pair of lead wires 24 drawn out of the case 21 are bent along the outer bottom surface 21a of the case 21 coated or coated with the insulating material 26, and the insulating material 26 is coated or coated. The outer bottom surface 21a of the case 21 is used as a mounting surface on a printed circuit board.

The gap between the pair of through holes 23 and the pair of lead wires 24 is sealed by a pair of sealing members 27 made of a rubber-like elastic material.
Is formed in a ring shape, and this ring-shaped sealing body 27 is located near the capacitor element 22 side and press-fitted into a pair of lead wires 24.

The dimensional relationship between the pair of through-holes 23 and the pair of lead wires 24 is such that the inner diameter of the pair of through-holes 23 is larger than the outer diameter of the pair of lead wires 24 into which the pair of sealing bodies 27 are press-fitted. The gap between the pair of through-holes 23 and the pair of lead wires 24 is sealed by making them smaller and press-fitting them. In this case, if the inner diameter of the pair of through-holes 23 is formed in a tapered shape that decreases from the inside of the case 21 to the outside, the fitting effect can be further enhanced.

Although the ring-shaped sealing member 27 is made of synthetic rubber such as butyl rubber, an elastomer or an adhesive suitable for liquid sealing may be applied.

A circular lid member 25 made of aluminum for sealing the opening of the bottomed cylindrical case 21 is attached to the opening end of the case 21 by joining. Any of joining, joining by welding, joining with an adhesive, and joining by fitting may be used, and the inside of the case 21 is sealed by this joining.

The bottomed cylindrical case 21 and the lid member 25 are made of aluminum. In this case, if the ring-shaped sealing body 27 is provided with electrical insulation, a short circuit between the anode and the cathode can be achieved. There is no problem.

In the above-described vertical chip-type aluminum electrolytic capacitor according to the first embodiment of the present invention, a gap between a pair of through holes 23 provided on the bottom of case 21 and a pair of lead wires 24 is formed by a pair of sealing members 27. Because of the hermetically sealed configuration, the sealing body 27 need only be extremely small, which can greatly reduce the height of the product.

Also, since the sealing body 27 is very small, the projected area of the sealing body 27 becomes extremely small, whereby the amount of the permeation of the driving electrolyte from the sealing body 27 can be greatly reduced. Therefore, the life of the capacitor can be further extended.

The exterior body of the chip type aluminum electrolytic capacitor has a case 21 made of aluminum.
And the lid member 25, the strength of the exterior body becomes extremely high. As a result, when the internal pressure of the capacitor rises during surface mounting on a printed circuit board by solder reflow, the case 21 and the lid member 25 are formed. Does not cause external deformation, so that sufficient mounting stability and sealing property can be ensured.

Further, the capacitor element 22 is configured in the same manner as a capacitor element having a conventionally used structure, and the sealing body 27 can be extremely small, so that it can be obtained at a low cost. Things.

Further, in the first embodiment of the present invention, since the insulating material 26 is sandwiched between the outer bottom surface 21a of the case 21 and the pair of bent lead wires 24, Contact between outer bottom surface 21a of case 21 and a pair of lead wires 24 and outer bottom surface 21 of case 21
The contact between a and the wiring pattern of the printed circuit board can be reliably prevented by the insulating material 26, thereby preventing a short circuit from occurring, thereby stabilizing the product characteristics.

(Embodiment 2) FIG. 3 is a perspective view of a vertical chip type aluminum electrolytic capacitor according to Embodiment 2 of the present invention, and FIG. 4 is a longitudinal sectional view of the capacitor.

The vertical chip type aluminum electrolytic capacitor according to the second embodiment of the present invention shown in FIGS. 3 and 4 is the same as the vertical chip type aluminum electrolytic capacitor according to the first embodiment of the present invention shown in FIGS. In place of the bottomed cylindrical aluminum case 21 and the circular aluminum lid member 25 for sealing the opening of the case 21 in the electrolytic capacitor, a bottomed rectangular cylindrical aluminum case 31 and a case 31 are provided. A rectangular lid member 35 made of aluminum for sealing the opening of the case 31 is used, and the other configuration is the same as that of the first embodiment of the present invention.

In the above-described second embodiment of the present invention, since the case 31 in which the capacitor element 22 is incorporated together with the driving electrolyte is formed in a rectangular tube having a bottom, FIGS.
The maximum space can be utilized in the mounting surface on the printed circuit board in the conventional structure shown in FIG. 2, that is, the same space as the mounting space occupied by the square insulated terminal plate 5, and thus, the built-in Since the amount of the driving electrolyte to be used can be greatly increased, the life of the capacitor can be further extended.

[0027]

As described above, the vertical chip type aluminum electrolytic capacitor of the present invention has a bottomed cylindrical case in which a capacitor element having a pair of lead wires is built in together with a driving electrolyte, and a bottom portion of the case. A pair of through holes provided and through which a pair of lead wires of the capacitor element penetrate and are drawn out of the case, a pair of sealing bodies for sealing a gap between the pair of through holes and the pair of lead wires, A lid member for sealing an opening of the bottomed cylindrical case, coating or applying an insulating material on an outer bottom surface of the case, and insulating a pair of lead wires drawn out of the case with the insulating material. Is bent along the outer bottom surface of the coated or coated case to form a mounting surface on the printed circuit board. According to this configuration, the case is made of a conductive material such as metal. Also, the contact between the outer bottom surface of the case and the pair of lead wires and the contact between the outer bottom surface of the case and the wiring pattern of the printed circuit board can be reliably prevented by the insulating material coated or applied to the outer bottom surface of the case. ,
As a result, the occurrence of a short circuit can be prevented, so that the product characteristics can be stabilized.

[Brief description of the drawings]

FIG. 1 is a perspective view of a vertical chip type aluminum electrolytic capacitor according to a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of the capacitor.

FIG. 3 is a perspective view of a vertical chip type aluminum electrolytic capacitor according to a second embodiment of the present invention.

FIG. 4 is a longitudinal sectional view of the capacitor.

FIG. 5 is a perspective view of a conventional vertical chip type aluminum electrolytic capacitor.

FIG. 6 is a longitudinal sectional view of the capacitor.

FIG. 7 is a perspective view of a vertical chip type aluminum electrolytic capacitor developed by the present inventors.

FIG. 8 is a longitudinal sectional view of the capacitor.

[Explanation of symbols]

 21, 31 Case 21a, 31a Outer bottom surface of case 22 Capacitor element 23 A pair of through holes 24 A pair of lead wires 25, 35 Cover member 26 Insulating material 27 A pair of sealing bodies

Claims (2)

[Claims] 1. A bottomed cylindrical case containing a capacitor element having a pair of lead wires together with a driving electrolyte,
A pair of through-holes provided at the bottom of the case and through which a pair of lead wires of the capacitor element penetrate and are drawn out of the case, and a pair of through-holes sealing a gap between the pair of through-holes and the pair of lead wires. A sealing body, having a lid member for sealing the opening of the bottomed cylindrical case, and coating or applying an insulating material to the outer bottom surface of the case,
A vertical chip type aluminum electrolytic capacitor in which a pair of lead wires drawn out of the case is bent along the outer bottom surface of the case coated or coated with an insulating material to be a mounting surface on a printed circuit board. 2. A vertical chip-type aluminum electrolytic capacitor according to claim 1, wherein a case in which the capacitor element is incorporated together with the driving electrolyte is formed in a rectangular tube having a bottom.