JPH09289137A - Axial chip aluminum electrolytic capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an axial chip aluminum electrolytic capacitor which can stabilize its characteristics by preventing contact between an outer bottom face of a case and a pair of lead wires as well as contact between the outer bottom face of the case and a wiring pattern on a printed circuit board. SOLUTION: A cylindrical bottomed case 21 containing a capacitor element 21 having a pair of lead wires 24 together with a driving electrolyte solution, is sealed with a lid member 28, and is provided on its outer bottom with an insulating terminal plate 25. The pair of leads 24 externally led out through a pair of through holes 23 made in the bottom of the case 21 and through a pair of through holes 26 made in the insulating terminal plate 25, is bent along a surface 25a of the insulating terminals plate. The insulating terminal plate surface 25a faces a printed circuit board when mounted.

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 in various electronic devices and surface-mounted on a printed circuit board.

[0002]

2. Description of the Related Art In recent years, surface mount components have been widely used in the industrial world in response to demands for miniaturization and high density packaging of electronic components used in various electronic devices. In the case of capacitors as well, in this flow, as an 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, FIG.
As shown in FIG. 2, the capacitor element 1 and the driving electrolytic solution are both housed in a bottomed cylindrical case 2 made of aluminum, and a pair of lead wires 3 provided in the capacitor element 1 is provided.
Is pulled out to the outside from the opening side of the case 2 by penetrating the sealing body 4 arranged in the opening of the case 2, and the case 2 is drawn and sealed.
A rectangular insulating terminal plate 5 is arranged on the sealing surface of
An external structure capable of surface mounting on a printed circuit board by penetrating a pair of lead wires 3 penetrating the sealing body 4 into 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.

Since the conventional vertical chip type aluminum electrolytic capacitors shown in FIGS. 5 and 6 described above use the radial type aluminum electrolytic capacitors, the radial type aluminum electrolytic capacitors can be used to reduce the height of the product. Although it is necessary to reduce the height itself, the conventional radial type aluminum electrolytic capacitor has a rubber opening at the opening of the case 2 for accommodating 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 body 4 made of the elastic body is used for sealing, if the height of the product is reduced as it is, the space for securing the amount of the driving electrolytic solution becomes small and the thickness of the sealing body 4 becomes thin. Therefore, the permeation of the driving electrolyte increases,
The problem is that the life of the capacitor characteristics is greatly affected.

Further, as the thickness of the sealing body 4 becomes thinner, the sealing strength also becomes weaker. Therefore, when the pressure inside the capacitor rises when solder reflow is performed at the time of surface mounting on a printed circuit board, the sealing body 4 swells, and This sealing body 4
Since the swelling of the resin affects the mounting stability on the 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 inventors of the present invention can reduce the height of the product by eliminating the thickness of the sealing body, which is required in the conventional structure, and at the same time, the sealing body. By significantly reducing the surface permeation amount of the driving electrolyte from, the life of the capacitor characteristics can be extended, and by further increasing the strength of the exterior body,
A configuration that ensures sufficient mounting stability and sealing performance during surface mounting on a printed circuit board by solder reflow, uses conventional capacitor elements, and requires less material for the sealing body. By doing so, we have developed a vertical chip-type aluminum electrolytic capacitor that can be obtained at low cost. That is, as shown in FIG. 7 and FIG. 8, a pair of through holes 13 are provided in the bottom of a cylindrical case 12 having a bottom, which houses a capacitor element 11 together with a driving electrolytic solution, and the capacitor is provided in the pair of through holes 13. The pair of lead wires 14 provided in the element 11 are penetrated and drawn out to the outside, and the gap between the pair of through holes 13 and the pair of lead wires 14 is sealed by a sealing body 15, and the bottomed cylindrical case is formed. A vertical chip type aluminum electrolytic capacitor having a structure in which the opening of 12 is sealed by a lid member 16 and a pair of lead wires 14 drawn out to the outside is bent along the outer bottom surface 12a of the case 12 has been developed.

[0006]

However, in the vertical chip type aluminum electrolytic capacitor having the structure shown in FIGS. 7 and 8, the capacitor element is provided in the pair of through holes 13 provided at the bottom of the cylindrical case 12 having a bottom. Since the pair of lead wires 14 provided in the connector 11 are penetrated and led out to the outside, and the pair of lead wires 14 pulled out to the outside are bent along the outer bottom surface 12a of the case 12 to form a mounting surface on the printed circuit board. When the case 12 is made of a conductive material such as metal, contact between the outer bottom surface 12a of the case 12 and the pair of lead wires 14 bent along the outer bottom surface 12a,
Alternatively, there is a problem that a short circuit occurs due to the contact between the outer bottom surface 12a of the case 12 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 the case and the pair of lead wires and contact between the outer bottom surface of the case and the wiring pattern of the printed circuit board. Therefore, it is an object of the present invention to provide a vertical chip type aluminum electrolytic capacitor capable of stabilizing product characteristics.

[0008]

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 incorporated together with a driving electrolytic solution. And a pair of through-holes provided at the bottom of the case and through which the pair of lead wires of the capacitor element penetrate and are drawn out of the case, and a gap between the pair of through-holes and the pair of lead wires is sealed. A pair of sealing bodies, a lid member that seals the opening of the bottomed cylindrical case, an insulating terminal plate disposed on the outer bottom portion of the case, and the insulating terminal plate, and A pair of through-holes through which a pair of lead wires penetrates and is drawn out to the outside, and a pair of lead-wires that extend through the pair of through-holes provided in the insulating terminal plate and are drawn out to the insulating terminal plate surface. Fold along, The insulating terminal board surface of is the mounting surface on the printed circuit board.With this configuration, 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 on the printed circuit board are prevented. It is possible to prevent this, and thereby to stabilize the product characteristics.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention is provided with a bottomed cylindrical case that houses a capacitor element having a pair of lead wires together with a driving electrolyte solution, and is provided at the bottom of this case. A pair of through-holes through which the pair of lead wires of the capacitor element penetrate and are drawn out of the case; and a pair of sealing bodies that seal a gap between the pair of through-holes and the pair of lead wires; A lid member that seals the opening of the bottom cylindrical case, an insulating terminal plate disposed on the outer bottom of the case, and an insulating terminal plate provided on the insulating terminal plate and through which the pair of lead wires penetrates to the outside. And a pair of through-holes that are pulled out to the insulating terminal board, and a pair of lead wires that are pulled out to the outside through the pair of through-holes provided in the insulating terminal board are bent along the insulating terminal board surface. The surface was surface-mounted on the printed circuit board. Since, according to this configuration, even when the configuration of a conductive material such as a metal case,
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 terminal board, which also prevents the occurrence of a 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 built in together with the driving electrolytic solution is a bottomed rectangular tube. According to this structure, the conventional rectangular insulating terminal plate occupies the case. Since the mounting space can be used to the maximum extent, the amount of the driving electrolyte contained in the case that constitutes the exterior body of the capacitor can be greatly increased, which further extends the life of the capacitor characteristics. It can be achieved.

Embodiments of the present invention will be described below with reference to the accompanying drawings. (Embodiment 1) FIG. 1 shows a perspective view of a vertical chip type aluminum electrolytic capacitor according to Embodiment 1 of the present invention.
FIG. 2 is a vertical sectional view of the same capacitor. In FIGS. 1 and 2, reference numeral 21 is a case made of bottomed cylindrical aluminum, and a capacitor element 22 is incorporated in the case 21 together with a driving electrolytic solution. A pair of through holes 23 are provided at the bottom of the case 21, and a pair of lead wires 24 included in the capacitor element 22 are passed through the pair of through holes 23.

Reference numeral 25 denotes an insulating terminal plate disposed on the outer bottom portion of the case 21 and made of a heat-resistant insulating material such as resin or ceramic. The insulating terminal plate 25 has a pair of through holes 26. The pair of through holes 26 are provided with a pair of lead wires 24 penetrating the bottom of the case 21 and penetrating to the outside. The pair of lead wires 24 led out to the outside are bent along the insulating terminal plate surface 25a, and the insulating terminal plate surface 25a is used as a mounting surface on the printed circuit board.

The gap between the pair of through holes 23 and the pair of lead wires 24 is a pair of sealing bodies 2 made of a rubber-like elastic body.
7, the pair of sealing bodies 27 are formed in a ring shape, and the ring-shaped sealing body 27 is located near the capacitor element 22 side and press-fitted into the pair of lead wires 24. Is what you are doing.

Further, 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 smaller than the outer diameter of the pair of lead wires 24 into which the pair of sealing bodies 27 are press-fitted. The above structure is formed by press-fitting them to seal the gap between the pair of through holes 23 and the pair of lead wires 24. In this case, if the inner diameter of the pair of through holes 23 is tapered so as to decrease from the inside to the outside of the case 21, 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 adhesive suitable for liquid sealing may be applied.

Reference numeral 28 denotes a circular lid member made of aluminum for sealing the opening of the bottomed cylindrical case 21.
The lid member 28 is attached to the open end of the case 21 by joining. The joining may be any of laser joining, welding joining, adhesive joining, and fitting joining, and the inside of the case 21 is sealed by this joining.

The bottomed cylindrical case 21 and the lid member 28 are made of aluminum. In this case, if the ring-shaped sealing body 27 is electrically insulated, a short circuit occurs between the anode and the cathode. There is no problem.

In the vertical chip type aluminum electrolytic capacitor according to the first embodiment of the present invention described above, the gap between the pair of through holes 23 provided in the bottom of the case 21 and the pair of lead wires 24 is provided by the pair of sealing bodies 27. Since the structure is hermetically sealed, the sealing body 27 need only be extremely small, and this can significantly reduce the height of the product.

Since the sealing body 27 is very small,
The projected area of the sealing body 27 becomes extremely small, and thus the surface permeation amount of the driving electrolyte solution from the sealing body 27 can be significantly reduced, so that the capacitor characteristics can have a long life. is there.

Since the exterior body of the chip-type aluminum electrolytic capacitor is made up of the case 21 and the lid member 28 made of aluminum, the strength of the exterior body becomes extremely strong, which allows the printed circuit board to be reflowed by solder reflow. At the time of surface mounting, even if the pressure inside the capacitor rises, the case 21 and the lid member 28 do not deform in appearance, so that the mounting stability and the sealing property can be sufficiently ensured.

Further, the capacitor element 22 is constructed in the same manner as the capacitor element having the structure which has been conventionally used, and the sealing body 27 can be extremely small.
It can be obtained at low cost.

Furthermore, in the first embodiment of the present invention, since the insulating terminal plate 25 is sandwiched between the outer bottom surface 21a of the case 21 and the pair of bent lead wires 24, Contact between the outer bottom surface 21a of the case 21 and the pair of lead wires 24 and the outer bottom surface 2 of the case 21
The contact between 1a and the wiring pattern of the printed circuit board can be surely prevented by the insulating terminal plate 25.
Since the occurrence of short circuit is eliminated, the product characteristics can be stabilized.

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

The vertical chip type aluminum electrolytic capacitor according to the second embodiment of the present invention shown in FIGS. 3 and 4 is the vertical chip type aluminum electrolytic capacitor according to the first embodiment of the present invention shown in FIGS. In place of the case 21 made of cylindrical aluminum having a bottom and the circular lid member 28 made of aluminum for sealing the opening of the case 21 in the electrolytic capacitor, a case 31 made of aluminum having a rectangular cylinder with a bottom and a case 31 made of aluminum A rectangular lid member 38 made of aluminum for sealing the opening of the case 31 is used, and other configurations are the same as those 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 electrolytic solution is in the shape of a bottomed rectangular tube, FIG. 5 and FIG.
The maximum space can be utilized in the printed circuit board mounting surface in the conventional structure shown in FIG. 6, that is, in the same space as the mounting space occupied by the rectangular-shaped insulating terminal board 5, and as a result, it is built in the case 31. Since the amount of the driving electrolytic solution can be greatly increased, the life of the capacitor characteristics can be further extended.

[0026]

As described above, the vertical chip type aluminum electrolytic capacitor of the present invention has a bottomed cylindrical case that houses a capacitor element having a pair of lead wires together with a driving electrolytic solution, and a bottom case. A pair of through holes that are provided and through which a pair of lead wires of the capacitor element penetrates and is drawn out of the case, and a pair of sealing bodies that seal the gap between the pair of through holes and the pair of lead wires, A lid member for sealing the opening of the bottomed cylindrical case, an insulating terminal plate arranged on the outer bottom of the case, and a pair of lead wires provided on the insulating terminal plate and penetrating therethrough. And a pair of through holes that are pulled out to the outside, and a pair of lead wires that are pulled out to the outside through the pair of through holes provided in the insulating terminal plate are bent along the surface of the insulating terminal plate, Print the terminal board surface With this configuration, even if the case is made of a conductive material such as metal, the contact between the outer bottom surface of the case and the pair of lead wires and the printing of the outer bottom surface of the case and the printed board The contact with the wiring pattern of the substrate can be surely prevented by the insulating terminal plate, and thus the occurrence of short circuit can be prevented, so that the product characteristics can be stabilized.

[Brief description of 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 vertical 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 vertical sectional view of the capacitor.

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

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

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

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

[Explanation of symbols]

 21, 31 Case 22 Capacitor Element 23 Pair of Through Holes 24 Pair of Lead Wires 25 Insulation Terminal Plate 25a Insulation Terminal Plate Surface 26 Pair of Through Holes 27 Pair of Sealing Body 28, 38 Lid Member

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tetsuo Sonoda 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (2)

[Claims] 1. A bottomed cylindrical case containing a capacitor element having a pair of lead wires together with a driving electrolytic solution,
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 for sealing a gap between the pair of through-holes and the pair of lead wires. A sealing member, a lid member that seals the opening of the bottomed cylindrical case, an insulating terminal plate disposed on the outer bottom portion of the case, and the pair of the pair of insulating terminals provided on the insulating terminal plate. A pair of through-holes through which lead wires penetrate and are drawn out to the outside, and a pair of lead wires that are drawn out to the outside through a pair of through-holes provided in the insulating terminal plate are arranged along the insulating terminal plate surface. Vertically mounted chip-type aluminum electrolytic capacitor characterized in that the surface of this insulated terminal plate is used as the mounting surface on the printed circuit board. 2. The vertical chip-type aluminum electrolytic capacitor according to claim 1, wherein the case in which the capacitor element is built in together with the driving electrolytic solution has a bottomed rectangular tubular shape.