JPH0950938A - Electric double-layer capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a gap small between lead terminals in a crosswise mounting- type electric double-layer capacitor without a decrease in stability for mounting a printed circuit board and mount an insulating board on an electrode face opposite the printed circuit board without using an additional special holding part. SOLUTION: A capacitor body 10 has coin-shaped capacitor cells 2 and 3, and lead terminals 12 and 13 are fixed to each electrode face. When both inserting legs 123 and 133 on each free end side are bent at right angles to the electrode face, a heat-resistant insulating plate 11 made of insulating material and smaller in diameter than the capacitor body 10 is put on the electrode- face side opposite the printed circuit board. In addition, the insulating plate 11 is held by middle parts 122 and 132 of each lead terminal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric double layer capacitor, and more specifically, it is equipped with a coin-type capacitor cell and is mounted in a horizontal position so that one electrode surface thereof faces a printed circuit board. It relates to an electric double layer capacitor.

[0002]

2. Description of the Related Art An electric double layer capacitor has a coin-shaped capacitor cell as a minimum unit and is used in a state in which a plurality of stacked capacitor cells are stacked according to the application, but since it is not provided with a terminal member itself. For example, when mounting on a printed circuit board, lead terminals are attached to the respective electrode surfaces.

FIG. 5 shows a capacitor body 1 as a conventional example thereof. That is, the capacitor body 1 is formed by stacking two capacitor cells 2 and 3. According to this, a cup-shaped coupling member 4 is attached to one of the capacitor cells 2 on the cathode surface 2a side by welding. The anode surface 3b side of the other capacitor cell 3 is fitted and held and welded to the same coupling member 4.

The capacitor body 1 is covered with a sleeve 5 made of a heat-shrinkable and electrically insulating resin, and lead terminals 6 and 7 are provided on the anode surface 2b and the cathode surface 3a located at both ends of the laminated body. Are attached respectively. In addition,
Since the cases of the capacitor cells 2 and 3, the coupling member 4, and the lead terminals 6 and 7 are each made of a stainless material, they are attached by, for example, laser welding.

As a mounting form of the capacitor body 1 on a printed circuit board (not shown), a so-called vertical type in which the electrode surfaces 2b and 3a are orthogonal to the printed circuit board surface, and one of the electrode surfaces 2b and 3a is the printed circuit board surface. There is a so-called horizontal type in which they are opposed to each other in parallel with each other, and they are appropriately selected depending on the design. However, when mounting in the horizontal state, as shown in FIG. , 7 are bent in the same direction so that their free ends (insertion legs) are substantially perpendicular to the electrode surfaces 2b, 3a of the same capacitor body 1.

That is, in this example, the lead terminal 7 attached to the cathode surface 3a on the side facing the printed circuit board is bent at a substantially right angle directly from its attachment base and attached to the other anode surface 2b. Lead terminal 6
Is bent substantially at right angles from the periphery of the capacitor body 1 along the side surface of the sleeve 5 so as to be parallel to the lead terminals 7 (see, for example, Japanese Utility Model Laid-Open No. 3730/1993).

[0007]

However, in this horizontal type, the lead terminals 6, 7 are provided on the capacitor body 1 for the purpose of enhancing the stability when mounting on a printed circuit board.
When attaching the lead terminals 6 and 7 with their attachment directions oriented so that their free ends are opposite to each other.
Since the space D between them is wide, it occupies a large space on the printed circuit board, and restricts the wiring of other mounting components. Also, the electrode surface on the side facing the printed circuit board, in this example, the cathode surface 3
Since a is exposed to heat during soldering, the characteristics of the capacitor may be adversely affected.

An electric double layer capacitor having a capacitor body similar to the one described above and surface-mounted by bending the free end side of each lead terminal to the outside is described in, for example, Japanese Utility Model Laid-Open No. 5-28023. As can be seen in the publication, the seat plate can be held by the respective lead terminals on the electrode surface side facing the printed circuit board. However, this inevitably requires a seat plate that is larger than the capacitor body, so that the occupied space on the printed circuit board becomes large, which is not preferable when high-density mounting is required. In addition, since the free end side of each lead terminal is bent outward to form a surface mount type, the seat plate can be held by using the lead terminal. The technique of this prior art cannot be directly applied to a so-called discrete type electric double layer capacitor that is inserted into a hole.

However, Japanese Utility Model Laid-Open No. 5-28023 discloses that in a discrete type electric double layer capacitor,
It has been proposed that a seat plate be interposed between the capacitor body and the printed circuit board to provide heat resistance. This electric double layer capacitor is a type in which a plurality of coin-shaped capacitor cells are housed in a cylindrical metal case with a bottom, an electrode plate is attached to the sealing part, and a pair of lead terminals is pulled out therefrom. Therefore, a seat plate smaller than the capacitor body can be used, but it cannot be denied that the number of parts is large and the cost is high as a whole.

The present invention has been made to solve such conventional problems, and an object thereof is to include at least one coin-shaped capacitor cell, and a lead terminal is provided on each electrode surface of the capacitor cell. Each of the lead terminals has a capacitor body formed by bending the free end side of each lead terminal in the same direction substantially perpendicular to the electrode surface, and is mounted so that one electrode surface of the capacitor body faces the printed circuit board. In the electric double layer capacitor, the space between the lead terminals can be narrowed without impairing the stability at the time of mounting on the printed circuit board, and the side facing the printed circuit board can be used without using a special holder as a separate component. An electric double layer capacitor with good heat resistance that allows an insulating plate smaller than the capacitor body to be attached to the electrode surface. There to be provided.

[0011]

To achieve the above object, the invention of claim 1 includes at least one coin-shaped capacitor cell, and a lead terminal is attached to each electrode surface of the capacitor cell. An electric double layer capacitor provided with a capacitor body formed by bending the free end side of each lead terminal in the same direction which is substantially perpendicular to the electrode surface, and one electrode surface of which faces the printed circuit board. In the above, an insulating plate made of a heat-resistant electric insulating material having a diameter smaller than that of the capacitor body is arranged on the one electrode surface side, and a holding portion for holding the insulating plate is provided on each of the lead terminals. It is characterized by According to this, the insulating plate can be attached to the electrode surface on the side facing the printed circuit board without using a special holder or the like as a separate component.

Further, according to a second aspect of the present invention, the holding portion is composed of a bent portion that is bent toward the center of the capacitor body so as to press the insulating plate at the intermediate portion of each lead terminal. According to this, the space between the lead terminals can be narrowed, and accordingly, the degree of freedom in drawing the wiring pattern on the printed circuit board is relaxed, and the wiring density can be increased in some cases. Becomes

In this case, as described in claim 3, the insertion legs for the printed circuit board which are connected to the bent portions of the lead terminals are arranged symmetrically with respect to the center of the capacitor body. Thereby, the interval between the lead terminals can be narrowed without impairing the stability when mounting on the printed circuit board.

On the other hand, according to a fourth aspect of the present invention, the insulating plate is bonded and held to the one electrode surface side via an adhesive material before being held by the lead terminals. According to this, the work of bending the lead terminal with respect to the insulating plate can be easily performed.

In this case, it is preferable that an ultraviolet curable adhesive material is used as the adhesive material. Further, in this connection, as described in claim 6,
It is preferable to form a through hole that allows the ultraviolet ray curable adhesive to be irradiated with ultraviolet rays at least in substantially the center of the insulating plate.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, specific examples of the electric double layer capacitor of the present invention will be described in more detail with reference to FIGS. In each of these drawings, the same reference numerals are used for constituent elements that are the same as or can be regarded as the same as those of the conventional example described above with reference to FIG.

FIG. 1 shows a completed view of a capacitor body 10 of an electric double layer capacitor according to the present invention. According to this, the insulating plate 11 is arranged on the electrode surface side facing the printed circuit board (not shown), and the insulating plate 11 is held so as to be held by the lead terminals 12 and 13.

The insulating plate 11 is made of a heat-resistant electric insulating material (for example, glass epoxy resin) and has an outer diameter smaller than that of the capacitor body 10. In this embodiment, the insulating plate 11 is formed in a disc shape, but may be a polygonal shape such as a triangle, a quadrangle, or a hexagon.
Moreover, the thickness is set arbitrarily.

The middle portion of each lead terminal 12 and 13 is bent toward the center of the capacitor body 10 so as to hold the insulating plate 11 from both sides thereof, whereby the distance D between the lead terminals 12 and 13 is conventionally reduced. It is narrower than the example. Even if the distance D is narrowed in this way, by mounting the free ends (insertion legs with respect to the printed circuit board) of the lead terminals 12 and 13 symmetrically with respect to the center of the capacitor body 10, the printed circuit board mounting is performed. The stability of time is not impaired.

Next, an example of a method of attaching the insulating plate 11 to the capacitor body 10 will be described with reference to FIGS. In these figures, the capacitor body 10 is drawn in an opposite manner to that of FIG.

As shown in FIG. 2, the capacitor body 10 is composed of two capacitor cells 2 and 3 laminated with a coupling member 4 interposed therebetween, which is similar to the conventional example.
One lead terminal 12 is attached to the anode surface 2b and the other lead terminal 13 is attached to the cathode surface 3a side. In this case, the lead terminals 12 and 13 are formed in advance as follows. .

That is, the lead terminal 12 has a mounting base 121 welded to the anode surface 2b, and an intermediate portion 122 bent from the peripheral edge of the capacitor body 10 along the sleeve 5 at substantially right angles to the mounting base 121. On the free end side of the intermediate portion 122, there is provided an inserting leg 123 for the printed circuit board, which is bent outward at a substantially right angle.

The intermediate portion 122 extends around the axial length of the capacitor body 10 toward the cathode surface 3a side, and the insulating plate 11
The length of the insertion leg 123 is such that the insertion leg 123 is substantially perpendicular to the printed circuit board (not shown) when the intermediate portion 122 is bent toward the cathode surface 3a side. It is bent almost at a right angle to.

The other lead terminal 13 has a mounting base 131 welded to the cathode surface 3a, an intermediate portion 132 raised substantially at a right angle from the mounting base 131, and a free end side of the intermediate portion 132 outwardly. The insert leg 133 for the printed circuit board bent at a substantially right angle is provided.

In this case, the intermediate portion 132 has a length capable of pressing the peripheral edge portion of the insulating plate 11 when the intermediate portion 132 is bent by approximately 90 degrees toward the center of the capacitor body 10. When bent in this manner, it is previously bent substantially at right angles to the intermediate portion 132 so as to be substantially perpendicular to a printed circuit board (not shown).

When the intermediate portions 122 and 132 are bent as described above to press the insulating plate 11,
The insertion legs 123 and 133 are the main body 10 of the capacitor.
The length is preferably such that it is arranged symmetrically with respect to the center of. Further, the lead terminals 12 and 13 are attached to the capacitor body 10 such that the insertion legs 123 and 133 thereof face in opposite directions.

When the insulating plate 11 is provided on the electrode surface facing the printed circuit board, in this example, on the cathode surface 3a side (actually, on the mounting base 131 of the lead terminal 13), in this example, an ultraviolet curable resin is used as an adhesive material. 14 is used to hold the insulating plate 11 by adhesion. Along with this, a through hole 111 for irradiating ultraviolet rays to the ultraviolet curable resin 14 is formed in the substantially central portion of the insulating plate 11.

After the insulating plate 11 is temporarily fixed by the ultraviolet curable resin 14, the intermediate portions 122 and 132 of the lead terminals 12 and 13 are directed toward the center of the capacitor body 10 as shown in FIG. And each of them can be bent approximately 90 degrees.

As a result, as shown in FIG.
The peripheral edge of the insulating plate 11 is pressed by the intermediate portions 122 and 132 and held on the cathode surface 3a, and the insertion legs 123 and 133 are oriented in the vertical direction. During the bending work, the insulating plate 11 is made of the adhesive material 1.
Since it has been bonded and held in advance at 4, there is no fear of falling off, and therefore the bending work can be performed easily.

[0030]

As described above, according to the present invention,
In a horizontal mounting type electric double layer capacitor, it becomes possible to attach an insulating plate made of a heat-resistant electric insulating material that is smaller than the capacitor element on the electrode surface side facing the printed circuit board, especially when soldering. An electric double layer capacitor having good heat resistance to heat is provided.

Even if the insulating plate is held on the electrode surface, the intermediate portion of each lead terminal is bent toward the center of the capacitor body, and the bent portion holds the insulating plate. The insulating plate can be reliably held without requiring new additional parts.

Further, as the middle portion of each lead terminal is bent toward the center of the capacitor body, the space between the respective insertion legs with respect to the printed circuit board is narrowed, so that the wiring pattern area on the printed circuit board is correspondingly reduced. Can be made large, the degree of freedom in drawing a wiring pattern can be relaxed, and the wiring density can be increased.

Even if the middle part of each lead terminal is bent toward the center of the capacitor body, the insertion leg for the printed circuit board connected to the bent part is symmetrical with respect to the center of the capacitor body. By arranging them, not only the spacing between the lead terminals can be narrowed without impairing the stability at the time of mounting on the printed circuit board, but also the spacing between the insertion legs can be adjusted according to the needs of the user side. It can be changed arbitrarily.

[Brief description of drawings]

FIG. 1 is an external perspective view of a capacitor body that substantially constitutes the electric double layer capacitor of the present invention.

FIG. 2 is a side view partially including a cross-section for explaining a preparation process for attaching an insulating plate to a capacitor body.

FIG. 3 is a side view partially including a cross section for explaining a state in which an insulating plate is temporarily fixed to a capacitor body and an intermediate portion of each lead terminal is bent.

FIG. 4 is a side view including a cross section in a part corresponding to FIG. 1 showing a state in which an intermediate portion of each lead terminal is bent and an insulating plate is held.

FIG. 5 is a side view showing a partial cross-section of a conventional horizontal mounting type electric double layer capacitor.

[Explanation of symbols]

 2,3 Coin-shaped capacitor cell 4 Coupling member 5 Sleeve 10 Capacitor body 11 Insulating plate 12,13 Lead terminal 121,131 Attachment base 122,132 Intermediate part 123,133 Insertion leg 14 Adhesive

Claims (6)

[Claims] 1. At least one coin-shaped capacitor cell is provided, and a lead terminal is attached to each electrode surface of the capacitor cell, and the free end side of each lead terminal is substantially the same as the electrode surface. In an electric double layer capacitor that is equipped with a capacitor body that is bent in one direction, and is mounted such that one electrode surface faces the printed circuit board, the electric double layer capacitor is formed on the one electrode surface side with a smaller diameter than the capacitor body. An electric double layer capacitor, wherein an insulating plate made of a heat-resistant electric insulating material is arranged, and each of the lead terminals is provided with a holding portion for holding the insulating plate. 2. The holding part comprises a bent part in which the middle part of each lead terminal is bent toward the center of the capacitor body so as to press the insulating plate. Electric double layer capacitor. 3. The insertion leg for a printed circuit board, which is connected to the bent portion of each of the lead terminals, is symmetrically arranged with respect to the center of the capacitor body. Electric double layer capacitor. 4. The electric double layer according to claim 1, wherein the insulating plate is adhesively held on the one electrode surface side via an adhesive material before being held by the lead terminals. Capacitors. 5. The electric double layer capacitor according to claim 4, wherein an ultraviolet curable adhesive is used as the adhesive. 6. The through hole according to claim 5, wherein at least a substantially central portion of the insulating plate is provided with a through hole that allows the ultraviolet curable adhesive to be irradiated with ultraviolet rays. Electric double layer capacitor.