JP2001314019A - Electric connection box using busbar - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric junction box using bus-bars, which makes it possible to improve the efficiency of heat radiation and uniformize the temperature. SOLUTION: Though large current flows in a bus-bar 3 in a first layer, heat generation is suppressed as the board is made thick. In addition, it is possible to uniformize the temperature between bus-bars radiating heat efficiently, since the bus-bar 3 is nearest to the open air.

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 using a laminated bus bar in which bus bars are laminated on an insulating substrate.

[0002]

2. Description of the Related Art Conventionally, as a structure of a bus bar constituting an internal circuit of an electric junction box such as a junction block or a relay box of an automobile, for example, Japanese Utility Model Laid-Open No.
There is a bus bar as disclosed in Japanese Patent No. 27968.

[0003] An electric connection box 10 shown in FIG.
As shown in FIG. 1, there is a laminated type in which the bus bar 103 is laminated inside the insulating substrate 105.

[0004]

However, the bus bar disclosed in Japanese Utility Model Laid-Open Publication No. 64-27968 has a heat radiation effect in a size regulated by using a thin sheet metal having the same thickness. Although the cross-sectional area can be increased in order to increase the height, there is a problem that the cross-sectional shape has to be processed into a corrugated or saw-toothed shape and the processing is troublesome.

In the case of the laminated type shown in FIG. 3, since the thickness t of the conductive thin plates constituting the bus bar 103 is all the same (for example, 0.64 mm), the current value is large. For example, the temperature rise is partially large in a portion connected to a (FAN RLY) fan relay or a (HTR RLY) heater relay, and particularly when such a fan relay or a heater relay portion is inside the laminate, heat is generated. There is a problem in that the insulating substrate 105 is easily trapped inside and may cause deformation or melting of the insulating substrate 105.

Accordingly, an object of the present invention has been made in view of the above-mentioned problems of the prior art, and uses a bus bar capable of improving heat radiation efficiency and achieving uniform temperature. An electrical junction box is provided.

[0007]

In order to achieve the above object, an electric connection box using a bus bar according to the first aspect of the present invention comprises an insulating bus bar made of a conductive sheet metal constituting a predetermined circuit. An electrical junction box used by laminating a plurality of bus bars at predetermined intervals in a substrate, wherein the thickness of the first layer bus bar closest to the outside air is the thickness of the bus bar of another layer among the plurality of bus bars. The first layer busbar is used for a large current.

Accordingly, although a large current flows through the first-layer bus bar, heat generation is suppressed because the plate thickness is increased.
In addition, since the first layer is closest to the outside air, the heat generated by the first layer bus bar is efficiently radiated to the outside air, and the temperature becomes uniform as a whole.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows an enlarged cross section of a main part of an electric junction box 1 according to the present invention, and FIG. 2 shows an example of an internal circuit of the electric junction box 1.

As shown in FIG. 1, in this electric junction box 1, the bus bars 3, 5, 7, 9 and the insulating portion 11
3 are alternately stacked to form a branch circuit, and the thickness T1 (for example, 0.8 mm) of the first-layer bus bar 3 (here, the first layer from the top) closest to the surface is: The other busbars 5, 7, and 9 are thicker than the plate thickness T2 (for example, 0.6 mm). Note that a tab 15 as a connection terminal is raised upward from the bus bar 3. A female-female relay terminal for connection with a terminal such as a relay is connected to the tab 15.

The first-layer bus bar 3 is connected to, for example, a power supply or an HTRRLY or FAN R shown in FIG.
When the current value such as LY is used, the thickness of the first-layer bus bar 3 is increased, so that even if a large current flows, heat generation can be suppressed and the first-layer bus bar 3 can be used. Since the bus bar 3 is closest to the outside air 17, heat can be efficiently radiated and the temperature rise of each of the insulating portions 11 in the lower stage can be made uniform. Further, since the bus bar 3 of the first layer is started up, the wiring of the second layer and thereafter is easy.

It should be noted that the present invention is not limited to the above-described embodiment of the present invention, but by making appropriate changes,
It can be implemented in other aspects. That is, in the above-described embodiment, the uppermost bus bar is the first-layer bus bar 3, but the lowermost bus bar may be the first-layer bus bar.

[0014]

As described above, in the electric connection box using the bus bar according to the first aspect of the present invention, a large current flows through the first-layer bus bar, but heat is generated because the plate thickness is increased. In addition to being able to suppress the temperature, it is possible to radiate heat efficiently because it is closest to the outside air, so that the temperature between the bus bars can be made uniform throughout.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view of a main part of an electric junction box using a bus bar according to the present invention.

FIG. 2 is an example of an internal circuit of an electric junction box using the bus bar of FIG. 1;

FIG. 3 is a partially enlarged sectional view of an electric junction box using a conventional bus bar.

[Description of Signs] 1 Electrical connection box 3 First-layer bus bar 5, 7, 9 Bus bar of other layer

Claims (1)

[Claims] 1. An electric connection box comprising a plurality of bus bars made of conductive sheet metal forming a predetermined circuit and laminated at predetermined intervals in an insulating substrate, wherein the plurality of bus bars are The thickness of the bus bar of the first layer closest to the outside air is made thicker than the thickness of the bus bar of the other layer, and the bus bar of the first layer is used for a large current. An electrical junction box using a bus bar.