JP2003087940A - Electric junction box - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively suppress the production of arcs when a current fuse is blown due to excessive current. SOLUTION: A capacitor 38 for the prevention of the production of arcs when the current fuse 16 is blown is installed in parallel with the current fuse 16 on installation terminals 36 on a bus bar board 14 on which terminals the current fuse is installed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric junction box in which a bus bar board is housed inside an insulating case.

[0002]

2. Description of the Related Art An electric connection box for branching and connecting a wire harness to various electric components is used in a 12V power distribution type low voltage system vehicle such as an automobile. This electrical junction box is constructed by housing a bus bar board with a current fuse attached inside an insulating case, and when an excessive current flows in the circuit in which the current fuse is inserted, the current fuse is The circuit is protected by melting due to self-heating.

[0003]

In recent years, technological innovations in the electric power system of automobiles have led to the development of high-voltage vehicles such as 36V system and 228V system in addition to the conventional low-voltage vehicle of 12V power distribution system. Even in such a high-voltage vehicle, the wire harness can be branched and connected to various electric components by using the electric connection box as in the case of the low-voltage vehicle.

However, in the case of a high-voltage vehicle, an arc is generated when the current fuse is blown by an excessive current, and a conductive material conductive path is formed between both terminals of the current fuse, making it impossible to completely cut off the circuit. There is a risk of becoming. For this reason, there is a demand for measures to prevent arcing when the current fuse is blown.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an electric junction box capable of effectively suppressing generation of an arc when a current fuse is blown by an excessive current. And

[0006]

In order to achieve the above object, the invention of claim 1 is an electric junction box in which a bus bar substrate to which a current fuse is attached is housed in an insulating case. It is characterized in that a capacitor for suppressing the generation of an arc when the current fuse is blown by an excessive current is attached in parallel with the current fuse.

According to this structure, the current fuse is blown when an excessive current flows in the circuit, but the electric energy for generating an arc when the fuse is blown is absorbed by the capacitor. For this reason, generation of an arc between both terminals of the current fuse is effectively suppressed, and a conduction path due to the arc is not formed between both terminals of the current fuse. Further, since it is not necessary to increase the distance between the terminals of the current fuse in order to avoid the occurrence of arc, there is no restriction on downsizing of the electrical junction box.

According to a second aspect of the present invention, in the first aspect, the current fuse is attached to an attachment terminal provided on the bus bar substrate, and the capacitor is formed on the attachment terminal. It is characterized by being attached to.

According to this structure, the current fuse and the capacitor are mounted on the common mounting terminal.
For this reason, the compact structure can be maintained even though the capacitor is attached in addition to the current fuse, and further, the design change of the bus bar circuit is not required.

According to a third aspect of the present invention, according to the second aspect, the mounting terminals are attached to the tab terminals, each of which is a pair of tab terminals in which the tip of the bus bar on the bus bar substrate is bent and stands upright. And a relay terminal formed of a pair having a mounting portion for mounting a current fuse, and the capacitor mounting portion is integrally formed with the tab terminal or the relay terminal.

According to this structure, the current fuse is attached to the relay terminal attached to the tab terminal, and the capacitor is attached to the capacitor attachment portion formed on the tab terminal or the relay terminal. For this reason, two electric components having different current fuses and capacitors are attached to the same attachment terminal in parallel with each other.

According to a fourth aspect of the present invention, in the third aspect, the tab terminal includes a terminal mounting piece to which the mounting portion of the relay terminal is mounted, and the capacitor includes a pair of lead terminals. Wherein the capacitor mounting portion is composed of an upright piece branched from the terminal mounting piece so as to have a gap into which the lead terminal can be inserted between the capacitor mounting portion and the terminal mounting piece. It is characterized by being.

According to this structure, the capacitor is attached by inserting each lead terminal into the gap formed between the terminal mounting piece of the tab terminal and the upright piece. Therefore, the work of mounting the capacitor on the mounting terminal becomes easy.

Further, the invention of claim 5 according to claim 4 is characterized in that the upright piece presses and holds the lead terminal inserted in the gap with the terminal mounting piece. I am trying.

According to this structure, the lead terminal is pressed and sandwiched between the terminal mounting piece and the upright piece to hold the capacitor on the mounting terminal. Therefore, the lead terminal is prevented from being accidentally detached from the mounting terminal, and the capacitor is securely mounted to the mounting terminal.

[0016]

1 is an exploded perspective view schematically showing a main part of an electric junction box according to an embodiment of the present invention.
In this figure, the electrical junction box 10 is an upper case 1
21 and the lower case 122 are fitted to each other, the insulating case 12 and the bus bar board 14 constituting the wiring unit arranged inside the insulating case 12. A printed circuit board, which constitutes an electronic circuit unit in which a predetermined electronic circuit such as a control circuit is configured, is mounted on the bus bar board 14 as needed, but it is omitted here.

The insulating case 12 is made of synthetic resin or the like, and a plurality of rectangular through holes 123 having a size through which the current fuse 16 can be inserted are arranged in a line at a predetermined position of the upper case 121. The guide portions 18 are formed in a line, and around each through hole 123, a guide portion 18 for guiding the current fuse 16 to the through hole 123 is formed. Further, a plurality of relay sockets 22 for mounting the relay 20 are attached to a predetermined portion of the upper case 121, and a plurality of connector sockets 26 for attaching the external connector 24 adjacent to the relay socket 22 are attached. Has been. The electrical junction box 10
Can be configured such that the current fuse 16 is simply attached to the bus bar substrate 14 without attaching the relay 20, the external connector 24, or the like.

The current fuse 16 disposed in the upper case 121 is, for example, as shown in FIG. 2, a pair of elongated metal plates which are arranged in parallel on the same plane and are opposed to each other at a predetermined interval. The terminal members 161, 162, a holding member 163 for holding the pair of terminal members 161, 162 in a state of being separated by a predetermined distance, and the holding member 163.
And a fusing member 164 disposed inside and connected between the pair of terminal members 161 and 162. The upper half of the pair of terminal members 161, 162 is covered with the holding member 163,
The lower half part is exposed from the holding member 163 and becomes the mounting leg parts 165 and 166 to the mounting terminal.

The busbar substrate 14 is provided with a long-sized busbar 30 formed by punching a metal plate on a rectangular insulating plate 28 made of synthetic resin or the like, and at a predetermined portion of the insulating plate 28. The tab terminals 32 are arranged in an upright state. The bus bar 30 is arranged in a plurality of layers separated from the insulating plate 28. In at least a part of the area, the bus bar 30 in the uppermost layer is the insulating plate 28.
Is exposed on the surface of the. The tab terminal 32 is formed by bending the tip of the bus bar 30 at a right angle, and is formed at a location corresponding to the current fuse 16, the relay 20, the external connector 24, and the like.

FIG. 3 is a view showing the structure around the tab terminal 32 which is formed in a pair on the bus bar substrate 14 at a position corresponding to the current fuse 16. Each of these tab terminals 32 has a terminal mounting piece 321 on which the relay terminal 34 to which the current fuse 16 is mounted is mounted, and a predetermined gap G is provided between the terminal mounting piece 321 and the terminal mounting piece 321. The upright piece 322 forming the capacitor mounting portion formed in this manner is formed.
In the vicinity of the corner of the upper end of the upright piece 322 on the side facing the terminal mounting piece 321, the terminal mounting piece 3 increases toward the top.
The tapered portion 323 is formed so as to be inclined in a direction away from 21.

The relay terminal 34 is bent in the left and right sides in a curved shape to form a mounting portion 341 for mounting on the tab terminal 32, while the upper half portion is bent in the left and right sides to form a box shape. The part 342 is formed, and the mounting part 344 of the current fuse having the press contact piece 343 bent from the upper end into the box-shaped part 342 is formed. In the relay terminal 34, the mounting portion 341 has the tab terminal 32.
Of the current fuse 16 and the mounting leg 165, 166 of the current fuse 16.
Is inserted and pressed by the press contact piece 343 to attach the current fuse 16. The tab terminal 32 and the relay terminal 34 form the mounting terminal 36 of the current fuse 16.

Further, the upright piece 322 is configured such that a pair of lead terminals 381 drawn out in the same direction from the capacitor 38 are pressed and sandwiched by the terminal mounting piece 321. That is, the gap G between the terminal mounting piece 321 and the upright piece 322 is the diameter (or width dimension) of the lead terminal 381.
It is set so as to be narrower than the upright piece 322 by a predetermined dimension.
When the lead terminal 381 is pressed down along the gap 3, the lead terminal 381 is pressed and sandwiched between the terminal mounting piece 321 and the upright piece 322.

The capacitance of the capacitor 38 is C, the electric energy when the current fuse 16 is blown is E,
When the power supply voltage is V, the capacitance C is E = (1 /
2) It is set to an approximate value of the value obtained based on the formula of CV ² . Further, this capacitor 38 has a power supply voltage V
A material having a withstand voltage characteristic that is not destroyed even when the above voltage is applied is selected. As such a capacitor 38, for example, an electric double layer capacitor can be used.

In the case of using the electric double layer capacitor as described above, by using a structure in which the sulfuric acid aqueous solution as the electrolytic solution can be replenished, it becomes possible to use it as a replenishing solution for the lead acid battery, and the electric double layer capacitor can be used. Maintenance of the multilayer capacitor becomes easy. In this case, the electric double layer capacitor is preferably provided with a gas vent.

In the electric connection box 10 according to the present embodiment having the above-described structure, the capacitor 38 is connected in parallel with the current fuse 16 attached to the attachment terminal 20, so that the current fuse 16 has an excessive current. The capacitor 38 absorbs the electric energy that generates an arc that is generated when it is melted. For this reason, generation of an arc between both terminals of the current fuse 16 is effectively suppressed, and a conduction path due to the arc is not formed between both terminals of the current fuse 16.

Further, in the electric junction box 10 according to the present embodiment, since the generation of an arc between both terminals of the current fuse 16 is suppressed, it is not necessary to increase the distance between both terminals of the current fuse 16, so that it is large. It is possible to reduce costs because the low-voltage vehicle and the high-voltage vehicle can be commonly used.

The electric junction box 10 according to the present invention is not limited to the above-mentioned embodiment, and various modifications as described below can be adopted.

(1) In the above embodiment, the capacitor 38
The capacitance C is set to an approximate value of the value obtained based on the equation of E = (1/2) CV ² , but it does not necessarily have to be this value. .
The point is that it is possible to effectively suppress the generation of an arc when the current fuse 16 is blown by an excessive current.

(2) In the above embodiment, the upright piece 322 is used.
Attaches the lead terminal 381 of the capacitor 38 to the terminal mounting piece 3
The capacitor 38 is held by pressing and sandwiching the capacitor 38 with 21, but the invention is not limited to this. For example, the gap G between the terminal mounting piece 321 and the upright piece 322 is set to a value larger than the diameter (or width dimension) of the lead terminal 381 of the capacitor 38, and the lead terminal 381 is wound around the upright piece 322. The capacitor 38 may be held by.

(3) In the above embodiment, the capacitor 38
Is attached by the upright piece 322 formed by branching from the terminal mounting piece 321 of the tab terminal 32.
It is not limited to this. For example, without forming the upright piece 322, the capacitor 38 is provided at an appropriate position on the tab terminal 32.
The lead terminals 381 of the
It is also possible to hold the capacitor 38 by inserting the lead terminal 381 of the capacitor 38 into a through hole formed at an appropriate position of 2 and soldering. In this case, a portion of the tab terminal 32 where the lead terminal 381 is soldered or where a through hole is formed constitutes a capacitor mounting portion.

Even when the upright piece 322 is formed, it may be bent at a right angle to the terminal mounting piece 321 as shown in FIG. 4, for example. In this case, the upright piece 322 has a capacitor 38 at the upper center.
It is sufficient to form a recessed portion 324 into which the lead terminal 381 is fitted.

(4) In the above embodiment, the shapes of the portions of the tab terminal 32 where the terminal mounting piece 321 and the upright piece 322 face each other are not particularly mentioned, but, for example, a top view of the main part of the tab terminal 32 is shown. 5, blade-shaped portions (pointed portions) 321a and 322a are formed at the portions of the terminal mounting piece 321 and the upright piece 322 that face each other, and the capacitor 38 is formed between these blade-shaped portions 321a and 322a. The lead terminal 381 may be pressed and sandwiched.

In this way, the blade portions 321a, 32a
Since each tip of 2a bites into the lead terminal 381, it is possible to more reliably prevent the lead terminal 381 from accidentally coming out from between the terminal mounting piece 321 and the upright piece 322. In addition, these blade portions 321a, 32
2a may be provided only on at least one of the portions of the terminal mounting piece 321 and the upright piece 322 that face each other.

(5) In the above-described embodiment, the capacitor mounting portion composed of the upright piece 322 is formed on the tab terminal 32, but the invention is not limited to this. For example, in FIG.
As shown in FIG.
5 may be provided, and a recess 346 into which the lead terminal 381 of the capacitor 38 is fitted may be formed at the upper center of the cut-and-raised piece 345 to serve as a capacitor mounting portion.

(6) In the above embodiment, the relay terminal 34
, The mounting portion 344 of the current fuse 16 is composed of the box-shaped portion 342 and the pressure contact piece 343, but is not limited to this. For example, as shown in FIG. 7, the mounting portion 344 may be configured by bending the left and right sides in a curved shape similarly to the mounting portion 341 in the lower half portion.

(7) In the above embodiment, the current fuse 16 is attached to the tab terminal 32 by using the relay terminal 34, but the present invention is not limited to this. For example, by forming a bifurcated portion to be fitted to the terminal mounting piece 321 at the tips of the mounting legs 165 and 166 of the current fuse 16, and fitting the bifurcated portion to the terminal mounting piece 321, the current fuse 16 is tabbed. It may be attached to the terminal 32.

(8) In the above embodiment, the capacitor 38
Uses a lead wire 381, but the present invention is not limited to this. For example, it is also possible to use a surface mount type having a terminal electrode. In this case, the terminal electrode may be attached to a part of the tab terminal 32 by soldering or the like.

[0038]

As described above, according to the present invention,
An electric junction box, in which a bus bar board to which a current fuse is attached is housed inside an insulating case,
A capacitor is installed in parallel with the current fuse to suppress arcing when the current fuse blows due to excessive current, so it is effective to prevent arcing when the current fuse blows due to excessive current. Can be suppressed.

[Brief description of drawings]

FIG. 1 is an exploded perspective view schematically showing a main part of an electrical junction box according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a configuration of a current fuse used in the electric junction box shown in FIG.

FIG. 3 is a diagram showing a configuration around a tab terminal of a bus bar board in the electrical junction box shown in FIG.

FIG. 4 is a diagram showing another configuration example of the tab terminal shown in FIG.

5 is a top view showing only a main part of the tab terminal shown in FIG.

6 is a diagram showing an example in which a capacitor mounting portion formed on the tab terminal shown in FIG. 3 is formed on a relay terminal.

FIG. 7 is a diagram showing another configuration example of the relay terminal shown in FIG.

[Explanation of symbols]

10 electrical junction box 12 Insulation case 14 Busbar board 16 current fuse 30 bus bars 32 tab terminals 34 Relay terminal 36 mounting terminals 38 capacitors 321 Terminal mounting piece 322 Upright piece 341 mounting part 344 mounting part 381 Capacitor lead terminal

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Fumiaki Mizuno             1-7-10 Kikuzumi, Minami-ku, Nagoya-shi, Aichi             Auto Network Technical Laboratory Co., Ltd. (72) Inventor Takahiro Onizuka             1-7-10 Kikuzumi, Minami-ku, Nagoya-shi, Aichi             Auto Network Technical Laboratory Co., Ltd. F-term (reference) 5G361 BA03 BB01 BB03 BC01                 5G502 AA01 BA05 CC14 CC25 EE02

Claims (5)

[Claims] 1. An electric junction box comprising a bus bar substrate to which a current fuse is attached and which is housed inside an insulating case, for suppressing the generation of an arc when the current fuse is blown by an excessive current. An electric junction box, wherein a capacitor is attached in parallel with the current fuse. 2. The current fuse is attached to a mounting terminal provided on the bus bar substrate, and the capacitor is mounted to a capacitor mounting portion formed on the mounting terminal. Electrical junction box. 3. The mounting terminal is composed of a pair of tab terminals in which a tip of the bus bar on the bus bar substrate is bent and stands upright, and a pair of mounting portions for mounting the tab terminals and mounting portions for mounting a current fuse. 3. The electrical junction box according to claim 2, wherein the electrical connection box comprises a relay terminal, and the capacitor mounting portion is integrally formed with the tab terminal or the relay terminal. 4. The tab terminal includes a terminal mounting piece to which the mounting portion of the relay terminal is mounted, the capacitor includes a pair of lead terminals, and the capacitor mounting portion includes the terminal. The electrical connection box according to claim 3, wherein the electrical connection box is formed by branching from the terminal mounting piece so as to have a gap into which the lead terminal can be inserted. . 5. The electrical junction box according to claim 4, wherein the upright piece presses and holds the lead terminal inserted in the gap with the terminal mounting piece.