JP2007336701A - Power supply distributor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power supply distributor having a means for dissipating heat in the housing inexpensively and efficiently without requiring an extra component. <P>SOLUTION: In the power supply distributor having a housing and a portion generating heat by switching-on, wall of the housing is provided contiguously to the heating element and the heating element can touch the outer air directly through the wall of the housing. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a power distribution device (hereinafter referred to as JB) used as a power distribution component for automobiles, and more particularly to a structure for efficiently and efficiently dissipating heat generated by energization.

  Conventionally, JBs used as power distribution parts for automobiles, etc. housed in a housing a circuit composed of a bus bar or rigid board, a fuse for the purpose of circuit protection, a relay for energizing and shutting off the circuit, etc. It has a structure. When these parts (fuses, relays) and members (circuits) are energized, they generate heat due to Joule heat, and therefore the temperature inside the JB housing tends to be high. When the temperature inside the housing becomes high, the thermal deterioration of each component is promoted, and the JB life may be shortened.

Conventionally, for example, techniques described in Patent Documents 1 and 2 have been proposed as means for suppressing temperature rise in the housing in JB.
In Patent Document 1, a predetermined circuit is formed, the circuit is housed in a case, and in an automobile electrical junction box in which a heat-generating component is mounted on the case, the heat generating part of the circuit in the case is near the heat generating part. A heat collecting plate separate from the case is provided, the working fluid is enclosed in a sealed tubular body, and the heat absorbing portion of the heat pipe having one end side as a heat radiating portion and the other end side as a heat absorbing portion is used as the heat collecting plate. An automobile electrical junction box is disclosed, characterized in that it is attached and the heat radiating portion protrudes outside the case.
In Patent Document 2, a fuse and / or relay is accommodated in a case, and an exhaust or intake opening is provided in a case or a part of the cover in an electrical junction box in which a cover is mounted, and the exhaust or exhaust is provided in the opening. An electric junction box having an electric fan for intake is attached.
Utility Model Registration No. 2582450 Japanese Utility Model Publication No. 3-91014

  However, in the prior art described in Patent Document 1 and Patent Document 2, extra parts such as a heat pipe and a heat collecting plate (Patent Document 1) and an electric fan (Patent Document 2) are installed on the JB for heat dissipation. There is a problem that leads to an increase in product cost. In addition, there are problems such as installing extra parts, leading to an increase in JB size, and limiting the degree of freedom in JB design.

  On the other hand, in the basic structure of JB not provided with the heat dissipating means described above, the JB housing has less unevenness in appearance for the purpose of not impairing the design. For this reason, the housing is dotted with empty rooms, in other words, rooms where only air exists. Since this room is in a state where there is little air convection, it is an insulating layer that prevents heat transfer between the inside of the housing and the outside air. 1 and 2 are diagrams illustrating a conventional JB 10 having an air chamber 14 as a heat insulating layer. FIG. 1 (a) is a front view of the JB 10, FIG. 1 (b) is a side view, and FIG. It is AA section sectional drawing in Fig.1 (a). In these drawings, reference numeral 10 is JB, 11 is a wall of the housing, 12 is a heating part (circuit part) of the substrate, 14 is an air chamber, and 15 is heat. In this conventional JB 10, as shown in FIG. 2, when the heat generating portion 12 generates heat by energizing the circuit of the substrate, the periphery of the heat generating portion 12 is covered with the wall 11 of the housing to form an air chamber 14. For this reason, good heat transfer is not performed in the heat radiation path indicated by the arrows (the heat generating portion 12 → the air chamber 14 → the housing wall 11 → the outside air surrounding the JB 10). As a result, heat is stored inside the housing, the inside of the housing is likely to become high temperature, the thermal deterioration of each component is promoted, and the JB life may be shortened.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a JB provided with means capable of radiating heat inside the housing inexpensively and efficiently without installing extra parts.

  In order to achieve the above object, according to the present invention, in a JB having a housing and a heat generating portion that generates heat by energization, a wall of the housing is provided adjacent to the heat generating element, and the heat generating element is interposed through the wall of the housing. Provided is a JB having a structure capable of directly contacting with outside air.

  In the JB of the present invention, it is preferable that the heat generating portion is a circuit configured by a bus bar or a rigid substrate.

  In the JB of the present invention, it is preferable that one or both of grease and a rubber sheet are interposed between the heat generating portion and the wall of the housing.

The JB according to the present invention has a housing wall adjacent to the heating element and a structure in which the heating element can come into direct contact with the outside air through the housing wall, so that a heat insulating layer is formed in the housing. The air chamber can be eliminated, good heat transfer can be performed, and the temperature rise in the housing can be suppressed.
Further, since the temperature rise in the housing can be kept low, the thermal deterioration of the parts can be suppressed, and the JB life can be extended.
Furthermore, in order to keep the temperature rise in the housing low, if there is a margin for the temperature rise, increase the circuit density to reduce the size, or reduce the arrangement interval of fuses, relays, etc. The degree of freedom can be expanded.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 3 is a view showing an embodiment of the JB according to the present invention. In the figure, reference numeral 12 denotes a heat generating part (circuit part), 13 denotes a rigid board, 20 denotes a JB, 21 denotes a housing wall, and 22 denotes heat. Represents each.

  The JB 20 of the present embodiment includes a housing and a heat generating portion 12 that generates heat when energized. A wall 21 of the housing is provided adjacent to the heat generating body 12, and the heat generating body 12 is outside air through the housing wall. It can be directly contacted with.

  In the present embodiment, a circuit unit provided on the rigid board 13 mounted on the JB 20 is illustrated as the heat generating unit 12, but the heat generating element is not limited to this, and for example, a circuit or circuit configured with a bus bar. It may be a fuse for the purpose of protection, a relay for energizing / cutting off the circuit, or the like.

  The JB 20 of the present embodiment can eliminate the air chamber (see reference numeral 14 in FIG. 2), which is a heat insulating layer, by providing the housing wall 21 adjacent to the heat generating portion 12. Thereby, the heat generating part 12 can be made into a structure which can be in direct contact with outside air through the wall of the housing. When the rigid substrate 13 is energized, heat 22 is generated in the heat generating part 12, but in this JB 20, the heat generating part 12 is in direct contact with the outside air through the wall of the housing. Heat is radiated directly to the outside of the housing.

The JB 20 of the present embodiment is provided with a housing wall 21 adjacent to the heat generating portion 12 and has a structure in which the heat generating portion 12 can be in direct contact with the outside air via the housing wall. The layered air chamber can be eliminated, good heat transfer can be performed, and temperature rise in the housing can be suppressed.
Moreover, since the temperature rise in the housing can be kept low, the thermal deterioration of the parts can be suppressed, and the life of the JB 20 can be extended.
Furthermore, in order to keep the temperature rise in the housing low, if there is a margin for the temperature rise, the circuit density is increased to reduce the size, or the arrangement interval of fuses, relays, etc. is reduced to reduce the size. The degree of freedom can be expanded.

In addition, this invention is not limited to the said embodiment, A various correction and change are possible.
For example, grease or a rubber sheet having good thermal conductivity may be inserted between the heat generating portion 12 and the wall 21 of the housing so that heat can be transmitted satisfactorily.

An example of conventional JB is shown, (a) is a front view of JB, and (b) is a side view. It is AA section sectional drawing of Fig.1 (a). It is a figure which shows one Embodiment of JB of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 12 ... Heat generating part (circuit part), 13 ... Rigid board | substrate, 20 ... JB, 21 ... Wall of housing, 22 ... Heat.

Claims (3)

In a power distribution device having a housing and a heat generating portion that generates heat when energized,
A power distribution apparatus comprising a housing wall adjacent to the heating element and a structure in which the heating element can directly contact outside air through the housing wall.   The power distribution device according to claim 1, wherein the heat generating unit is a circuit formed of a bus bar or a rigid board. 3. The power distribution device according to claim 1, wherein one or both of grease and a rubber sheet are interposed between the heat generating portion and the wall of the housing.

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