JPH0950937A - Electric double layer capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a gap small between lead terminals without a decrease in stability when a printed circuit board is mounted, by using a heat-resistant insulating plate made of insulating material and not larger than the size of a capacitor, and providing the insulating plate on an electrode side face. SOLUTION: An insulating plate 11 is put on an electrode side opposite a printed circuit board, while the insulating board 11 is held by first and second lead terminals 12 and 13. In addition, good heat-resistant characteristics are ensured during a soldering step. Since the insulating plate 11 is held at each middle bent part of the lead terminals 12 and 13, the insulating board 11 can be held surely without using an additional part. In addition, a spaced width between their legs inserted to the printed circuit board can be reduced, and thereby a wiring pattern region can be increased on the printed circuit board. The flexibility in drawing a pattern on the circuit board can be increased, and at the same time the wiring density can be increased.

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. 6 shows a capacitor body 1 as a conventional example. 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, 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. Excellent heat resistance with the ability to attach an insulating plate to the electrode surface that has a diameter that is approximately the same as or smaller than that of the capacitor body. It is to provide a double-layer capacitor.

[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, one of the leads attached to the one electrode surface is provided with an insulating plate made of a heat-resistant electric insulating material having a diameter substantially equal to or smaller than that of the capacitor body on the one electrode surface side. The terminal penetrates through the insulating plate, and the above-mentioned capacitor is formed in the middle part of the other lead terminal attached to the other electrode surface. Bent toward the center of the main body is characterized by holding portions for holding a peripheral portion of the insulating plate is formed. 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, since the other lead terminal is bent toward the center of the capacitor body, the distance between the lead terminals can be narrowed.

According to a second aspect of the present invention, the insulating plate is provided with a slit-shaped lead insertion hole through which the one lead terminal is forcibly inserted. According to this, the insulating plate is formed. Until it is held by the holding portion of the other lead terminal, the insulating plate is held on the one electrode surface by the frictional force between the lead insertion hole and the one lead terminal. The lead insertion hole may be a lead insertion hole having a size in which the one lead terminal is loosely fitted, as described in claim 3.

Further, as described in claim 4,
A holding portion, which is bent toward the center of the capacitor body and holds the insulating plate, may be formed in the middle portion of the one lead terminal as in the other lead terminal.

According to a fifth aspect of the present invention, the insertion legs of the lead terminals with respect to the printed circuit board are symmetrically arranged with respect to the center of the capacitor body. The distance between the lead terminals can be reduced without impairing the stability when mounting on the board.

[0015]

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. 1 to 5. In each of these drawings, the same reference numerals are used for the 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 by the first and second lead terminals 12 and 13.

The insulating plate 11 is made of a heat-resistant electric insulating material (for example, glass epoxy resin), and in this example,
The outer diameter is substantially the same as that of the capacitor body 10. The insulating plate 11 may have a smaller diameter than this, but the lower limit of the insulating plate 11 covers the mounting base 131 of the second lead terminal 13 described later and is exposed outside the intermediate portion 132 of the terminal 13. It is sized and may have any thickness.

Further, as shown in FIG. 2, the insulating plate 11 has lead insertion holes for inserting the second lead terminals 13. In this case, the lead insertion hole is formed in the second lead terminal 1 as shown in FIG.
3 is either a slit hole 11a forcibly inserted, or a rectangular hole 11b sized to allow the second lead terminal 13 to be loosely fitted, as shown in FIG. Good. When the slit hole 11a of FIG. 2A is used, the insulating plate 11 is held by the frictional force,
For example, it is possible to prevent accidental dropping due to a shock during transportation.

The middle portion of each lead terminal 12, 13 is bent toward the center of the capacitor body 10 so as to hold the insulating plate 11, whereby the lead terminal 1 is formed.
The distance D between 2 and 13 is narrower than in the conventional example. In addition,
Even if the distance D is narrowed in this way, the lead terminal 1
By arranging the free ends 2 and 13 (insertion legs with respect to the printed circuit board) symmetrical with respect to the center of the capacitor body 10, the stability when mounting the printed circuit board 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. Further, the insulating plate 11 has a lead insertion hole formed as a rectangular hole 11b in FIG. 2B.

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

That is, the first lead terminal 12 is the anode surface 2
mounting base 121 welded to b and capacitor body 1
Mounting base 121 along the sleeve 5 from the periphery of 0
An intermediate portion 122 bent substantially at a right angle to
On the free end side of the intermediate portion 122, the insertion leg 123 for the printed circuit board bent outward at a substantially right angle.
And

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 outside.

The second lead terminal 13 is provided with a mounting base 131 welded to the cathode surface 3a, an intermediate portion 132 standing up from the mounting base 131 at a substantially right angle, and linearly connected to the intermediate portion 132. And the insert leg 133 for the printed circuit board.

In this case, the intermediate portion 132 has such a length as to be able to press the peripheral edge portion of the lead insertion hole 11b when it is bent approximately 90 degrees toward the center of the capacitor body 10, and the insertion leg 133 has the intermediate portion 132 thereof. Is bent so as to be substantially vertical to the printed circuit board, and has a length substantially the same as the insertion leg 123 of the first lead terminal 12.

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.

The insulating plate 11 is provided on the electrode surface facing the printed board, that is, on the cathode surface 3a side in this example.
In this case, the lead insertion hole 11b is formed in the second lead terminal 1
It is arranged on the cathode surface 3a by being inserted into the surface 3.

This state is shown in FIG. Then, the intermediate portions 122, 13 of the lead terminals 12, 13
2 are bent by approximately 90 degrees toward the center of the capacitor body 10. In this case, the second lead terminal 1
3 has its insertion leg 133 held vertically, and only its intermediate portion 132 is bent 90 degrees.

Unlike this, the second lead terminal 1
The insertion leg 133 of No. 3 is the insertion leg 1 of the first lead terminal 12.
As in the case of No. 23, it is bent in the outward direction at a substantially right angle in advance, and the insulating plate 11 is laterally inserted into the insertion leg 133.
After being placed on the cathode surface 3a so as to be inserted into the
The middle portion 132 of the lead terminal 13 may be bent 90 degrees.

As a result, as shown in FIG.
The peripheral portion of the insulating plate 11 is the intermediate portion 1 of the first lead terminal 12.
22 and the lead insertion hole 11b is pressed by the intermediate portion 132 of the second lead terminal 13,
The insulating plate 11 is held on the cathode surface 3a, and the insertion legs 123 and 133 are vertically oriented.

The lead insertion hole of the insulating plate 11 is shown in FIG.
In the case of the slit hole 11a of (a), the insulating plate 11 is held by the fitting frictional force, so in some cases, without bending the intermediate portion 132 of the second lead terminal 13 as described above, You may keep it straight.

[0032]

As described above, according to the present invention,
In a horizontal mounting type electric double layer capacitor, it is possible to attach an insulating plate made of a heat-resistant electric insulating material that does not protrude outside the capacitor body to the electrode surface side facing the printed circuit board. Provided is an electric double layer capacitor having good heat resistance against heat applied.

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

Further, as the middle portion of each lead terminal is bent toward the center of the capacitor body, the distance between the respective insertion legs with respect to the printed circuit board is narrowed, and 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 portion 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 portion 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 plan view showing an insulating plate attached to the capacitor body.

FIG. 3 is a side view including a part of a cross section for explaining a preparation process for attaching an insulating plate to a capacitor body.

FIG. 4 is a side view including a cross section for explaining a state in which an insulating plate is arranged on a capacitor body and an intermediate portion of each lead terminal is bent.

FIG. 5 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. 6 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 11a, 11b Lead insertion hole 12 First lead terminal 13 Second lead terminal 121,131 Mounting base 122,132 Intermediate part 123,133 Insert leg

Claims (5)

[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 one of its electrode surfaces is mounted so as to face the printed circuit board, the one electrode surface side has approximately the same diameter as the capacitor body or An insulating plate made of a heat-resistant electric insulating material having a smaller diameter is arranged, and one lead terminal attached to the one electrode surface penetrates the insulating plate and at the other electrode surface. In the middle part of the other attached lead terminal,
An electric double layer capacitor, comprising: a holding portion that is bent toward the center of the capacitor body and holds a peripheral portion of the insulating plate. 2. The electric double layer capacitor according to claim 1, wherein the insulating plate is provided with a slit-shaped lead insertion hole through which the one lead terminal is forcibly inserted. 3. The electric double layer capacitor according to claim 1, wherein the insulating plate is provided with a lead insertion hole having a size into which the one lead terminal is loosely fitted. 4. The intermediate portion of the one lead terminal,
The electric double layer capacitor according to claim 1, further comprising a holding portion that is bent toward the center of the capacitor body to hold the insulating plate. 5. The electric double layer capacitor according to claim 1, wherein the insertion legs of the lead terminals with respect to the printed circuit board are symmetrically arranged with respect to the center of the capacitor body.