JPH09203595A - Radiator device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cause a weight of a radiator to be light and improve thermal radiation efficiency by a method wherein a base section for transmitting heat from a heat generating section and dispersing heat in a wide range and a fin section for use in transmitting heat top air are made of different metals having different material qualities. SOLUTION: In case that a heat generating member 5 of a thermal radiator device is placed at the center of a bottom surface of a base section, heat generated from the heat generating member 5 is transmitted in directions 6, 7, 8, and 9 in the entire region of the base section 1, transmitted to an opposite side of the base section 1 and further transmitted to a fin section 2. During this process of heat transfer, a heat exchanging operation with air is mainly carried out at the surface of the fin section 2, resulting in that the radiator device can be cooled and the heat generating member can be cooled. In this case, the base section 1 and the fin section 2 of the radiator device are made of different kind of metals. That is an aluminum plate or a copper plate is selected and applied to the base section 1 and the fin section 2 in accordance with a shape of the radiator device. Then, the base section 1 and the fin section 2 are connected and fixed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat dissipation device for dissipating heat generated by a semiconductor or the like of a power supply device.

[0002]

2. Description of the Related Art FIG. 5 shows an example of a conventional technique. FIG.
In the heat dissipation device, the base portion 51 and the fin portion 52 are made of the same metal material. It is generally made by extrusion using a high thermal conductivity metal such as aluminum or copper. For example, a heating element 55 attached to the center of the bottom surface of the base portion 51 of the heat dissipation device shown in the shaded portion of FIG. 5C.
The heat generated at is transmitted to the entire area of the base portion 51,
It is transmitted to the opposite side of the base portion 51 and is transmitted to the fin portion 52. In the fin portion 52, heat is transferred in the direction of arrow 53. In the course of this heat transfer, heat is exchanged with the air mainly on the surface of the fin portion 52 to cool the radiator and cool the heating element 55.

Aluminum has a thermal conductivity of about 240 W / mK at a temperature of 100 ° C., and copper has a thermal conductivity of 100 ° C.
Since the heat conductivity of copper is about 395 W / mK, the heat conductivity of copper is about 1.65 times that of aluminum.
Since the transmissivity from the base part 51 to the fin part 52 is higher when copper is used as the heat dissipation material,
The cooling effect of 5 is also high. That is, for a heating element having a large heating value, a higher cooling and hardening can be obtained by forming a copper radiator.

[0004]

A heat dissipation device using an aluminum material is widely used because of its light weight and relatively high heat dissipation efficiency. On the other hand, a copper material having a high thermal conductivity is used for a heating element that generates a large amount of heat. However, while copper has a high thermal conductivity, it has a problem that it cannot be made as lightweight as aluminum because it has a high density.

[0005]

According to the first aspect of the invention, there is provided a heat dissipation device comprising a base part for transferring heat from a heat generating part to disperse the heat in a wide range and a fin part for transferring the heat to air. In the device, a metal of a different material is used for the base portion and the fin portion. In other words, by combining a high thermal conductivity metal and a lightweight metal,
It is a light weight and high heat dissipation device.

A second aspect of the present invention is the heat radiating device according to the first aspect, wherein the base part and the fin part are joined by caulking.

A third aspect of the present invention is the heat radiating device according to the first aspect, wherein the base portion and the fin portion are joined by an adhesive material.

A fourth aspect of the present invention is the heat radiating device according to the first aspect, wherein the base part and the fin part are joined by brazing.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a heat dissipation device according to the first to fourth inventions will be described with reference to FIGS. 1 to 4, respectively.

1 (a), 1 (b) and 1 (c) show the base portion 1 and the fin portion 2 of the heat dissipation device in the front, side and bottom surfaces by trigonometry. FIG. 1 shows the base portion 1 and the fin portion 2 of the heat dissipation device.
Is composed of dissimilar metals. The heat dissipation device is configured using a metal having a high thermal conductivity such as aluminum or copper.
The base portion 1 and the fin portion 2 are joined and fixed.

In FIG. 1C showing the bottom surface of the heat dissipation device, when the heating element 5 shown by the hatched portion is placed at the center of the bottom surface of the base portion, the heat generated from the heating element 5 is generated by the base portion 1.
Is transmitted in the directions of 6, 7, 8 and 9 shown in the figure, is transmitted to the opposite side of the base portion 1 and is transmitted to the fin portion 2. In the fin portion 2, heat is transferred in the direction of arrow 11. In the course of this heat transfer, heat is exchanged with the air mainly on the surface of the fin portion 2, so that the heat dissipation device and the heating element can be cooled.

Aluminum has a thermal conductivity of about 240 W / mK at a temperature of 100 ° C., and copper has a thermal conductivity of 100 ° C.
Is about 395 W / mK. When aluminum or copper is used as the material of the heat dissipation device, the thermal conductivity of copper is about 1.65 times that of aluminum. On the other hand, the density of aluminum is 2.69 grams per cubic centimeter and the density of copper is 8.96 per cubic centimeter.
Since it is in grams, copper is 3.33 times heavier than aluminum. The present invention for constructing a heat dissipation device that is lightweight and has high thermal conductivity by utilizing the above characteristics of metals will be described below.

In the first aspect of the invention, the heat conductivity of the entire heat dissipation device can be adjusted by using different metals for the base portion 1 and the fin portion 2. For a heat dissipation device whose bottom surface area shown in FIG. 1C is larger than that of the heating element 5, the heat generated by the heating element 5 is 6,
It is transmitted in the directions of 7, 8 and 9. The degree of heat transfer is determined by the thermal conductivity of the metal in the directions of 6, 7, 8 and 9. Therefore, when the area of the bottom surface is large, it is desirable to use a material having a high thermal conductivity so that heat is transferred from corner to corner. Therefore, copper is used for the base portion 1 rather than aluminum. On the other hand, in the case where the area of the bottom surface of the base portion 1 is equal to that of the heating element and the fin portion 2 is relatively long, a material having a high thermal conductivity is used for the fin portion 2 so that heat can be transmitted to the tip. Use metal. That is, copper is used rather than aluminum. That is, depending on the shape of the heat dissipation device,
A plate made of aluminum or copper is selected and used for the base portion 1 and the fin portion 2.

An embodiment of the second invention is shown in FIG. FIG. 2 shows the inside of the dotted line 10 of the radiator corner of FIG.
It is an enlarged view which changed into invention of this. FIG. 2 illustrates a method of joining the base portion 11 and the fin portion 12,
A cross-sectional view of a joint portion between the base portion 11 and the fin portion 12 is shown. The base portion 11 is provided with a groove 4, the fin portion 12 is inserted into the groove 4, and both sides of the groove 4 are caulked by a caulking tool having a sharp tip to form a caulking recess 3. By forming the depression 3, the entrance of the groove 4 is narrowed and the fin portion 12 is tightened. By tightening the fin portion 12 in this manner, the base portion 11 and the fin portion 12 are firmly fixed.

An embodiment of the third invention is shown in FIG. FIG. 3 is an enlarged view in which the dotted line inside 10 of the heat dissipation device corner of FIG. 1B is changed to the third invention. In the invention of FIG. 3, the base portion 3
1 is provided with a groove 34 for the fin portion 32, and an adhesive 33 having a high thermal conductivity for metal is applied to the groove 34 to form the fin portion 3
When 2 is inserted, the base 33 and the fins 32 are firmly fixed after the adhesive 33 is solidified.

An embodiment of the fourth invention is shown in FIG. FIG. 4 is an enlarged view in which the dotted line inside 10 of the heat dissipation device corner of FIG. 1B is changed to the fourth invention. In the invention of FIG. 4, the base portion 4
A groove 44 for the fin portion 42 is formed in the groove 1, and a brazing material 43 is inserted between the base portion 41 and the fin portion 42 to perform brazing at high temperature. Brazed base portion 41 and fin portion 4
2 is firmly fixed.

[0017]

The thermal conductivity of aluminum has a temperature of 100 ° C.
Is about 240 W / mK, and the thermal conductivity of copper is 100
It is about 395 W / mK at ° C. When aluminum or copper is used as the material of the heat dissipation device, the thermal conductivity of copper is about 1.65 times that of aluminum. On the other hand, the density of aluminum is 2.69 grams per cubic centimeter and the density of copper is 8.9 per cubic centimeter.
At 6 grams, copper is 3.33 times heavier than aluminum. The above uses different metals having different properties of thermal conductivity and different density, and the base part 1 and the fin part 2 of the heat dissipation device shown in FIG. 1 are made of metal such as aluminum or copper. By composing the heat dissipation device in combination, it is possible to provide a heat dissipation device that is lighter in weight than the heat dissipation device made of all copper and has a higher thermal conductivity than the heat dissipation device made of all aluminum.

[Brief description of drawings]

FIG. 1 is a drawing of an embodiment of the first invention.

FIG. 2 is a drawing of an embodiment of the second invention.

FIG. 3 is a drawing of an embodiment of the third invention.

FIG. 4 is a drawing of an embodiment of the fourth invention.

FIG. 5 is a connection diagram of an embodiment of the prior art.

[Explanation of symbols]

1, 31, 41 Base portion 2, 32, 42 Fin portion 3 Recessed portion 4, 34, 44 Groove 5 Heating element 6, 7, 8, 9, 56, 57, 58, 59 Heat conduction direction 10 Radiator corner 11, 53 direction of heat conduction 33 adhesive 43 brazing material 51 base portion 52 fin portion

Claims (4)

[Claims] 1. A radiator comprising a base portion for transmitting heat from a heat generating portion to disperse the heat in a wide range and a fin portion for transmitting the heat to air, wherein the base portion and the fin portion are made of different materials. A heat dissipation device characterized by using metal. 2. The heat dissipation device according to claim 1, wherein the base part and the fin part are joined by caulking. 3. The heat dissipation device according to claim 1, wherein the base part and the fin part are joined by an adhesive material. 4. The heat dissipation device according to claim 1, wherein the base part and the fin part are joined by brazing.