JPH071828Y2 - Natural cooling type radiator for electric elements - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a naturally cooled radiator for an electric element. More specifically, a heat-generating component such as a transistor, a diode, or a thyristor is attached to a metal substrate, and air or the like is naturally circulated from one to the other in each cross-section rectangular channel of the fin fixed to the metal substrate, The present invention relates to a natural cooling type radiator for electric elements that dissipates heat generated inside a heat generating component.

[Conventional technology]

A fin provided with a large number of rectangular cross-section flow paths is fixed to a metal substrate, and air or the like is circulated from one side to the other in the cross-section square flow path of the fins so that heat from heat-generating components attached to the metal substrate is removed. As a radiator for electric elements that radiates heat, Shokai 62-19635
As can be seen in Japanese Patent Publication No. 3, the fin is formed to have a thicker wall in accordance with the metal substrate side, and the hydraulic radius of each cross-section rectangular channel of the fin (the hydraulic radius in the present specification means a cross section through which a fluid such as air flows). A device is provided in which the cross-sectional area of a rectangular channel is divided by the perimeter of the cross-section of the rectangular channel) is formed so as to increase along the metal substrate side.

This conventional product facilitates the transfer of heat generated from the heat-generating components to the fins, and further improves the heat dissipation efficiency by allowing more fluid such as air to flow in the rectangular cross-section flow path on the metal substrate side. It was done.

[Problems to be solved by the device]

The above-mentioned conventional product is most suitable as a so-called forced cooling type radiator for electric elements in which a fluid is forced to flow into each rectangular cross section by a fan or the like. However, it is not always satisfactory as a natural cooling type radiator for electric elements that allows a fluid such as air to flow naturally.

The present invention was devised in view of the fact that in the case of natural cooling, the greater the temperature difference between the fin and the fluid, the better the fluid flow. (EN) Provided is a naturally cooled radiator for electric elements, which has good heat dissipation efficiency, reduces the fin material, and is downsized by forming the hydraulic radius of the rectangular flow path to be smaller as it approaches.

[Means for Solving the Problems]

According to the present invention, there is provided a natural cooling type radiator for electric elements, in which a fin provided with a large number of rectangular cross-section flow passages is fixed to a metal substrate on which heat-generating components are mounted, and a fluid such as air is flowed in each cross-section square flow path. It is designed to flow naturally in the channel, and the hydraulic radius of the cross-section rectangular channel of the fin is formed small near the mounting position of the heat generating component, and the hydraulic radius becomes larger as it goes away from the mounting position. It is characterized by being.

[Function of device]

The naturally cooled radiator for electric elements of the present invention has a metal substrate on which heat-generating components such as transistors are attached, and air is naturally circulated from one side to the other in each cross-section rectangular channel of the fin to generate heat. The heat generated inside the component is transferred to the fin through the metal substrate to radiate the heat.

In the present invention, the hydraulic radius of the cross-section rectangular flow path near the mounting position of the heat-generating component of each cross-section square flow path of the fin is formed to be small, so that the fin material can be reduced accordingly and the size can be reduced. Become. Also, in the case of the natural cooling type, the larger the difference between the fin temperature and the fluid temperature, the better the fluid flows even if the hydraulic radius of the rectangular cross section is small. The flow of the fluid becomes good also in the cross-section rectangular flow path in the vicinity.

〔Example〕

 Next, an embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a perspective view with one portion cut away, FIG. 2 is a front view, and FIG. 3 is a front view showing another embodiment.

The naturally cooled radiator for an electric element according to the present invention comprises a metal substrate 1 and fins 2 as shown in FIGS. 1 to 3, and these metal substrate 1 and fins 2 are For example, the heat conducting member is made of aluminum alloy, copper or the like. A plurality of heat-generating components 3 such as transistors and diodes are attached to the metal substrate 1, and a plurality of flow paths 21, 22, 23 having a rectangular cross section are provided in the fin 2, and the fin 2 is made of the above-mentioned metal. It is fixed to the substrate 1. The fin 2 is fixed to the metal substrate 1 by brazing, for example. The horizontal radii of the rectangular flow paths 21, 22, 23 of the fin 2 are formed to be small in the vicinity of the mounting position of the heat-generating component 3 mounted on the metal substrate 1 and increase as the distance from the mounting position increases. It is formed on. That is, the hydraulic radius of the rectangular cross-section channel 21 is smaller than that of the rectangular cross-section channel 22, and the hydraulic radius of the rectangular cross-section channel 22 is smaller than that of the rectangular cross-section channel 23. To reduce the hydraulic radius, the perimeter of the cross section of the flow channel should be made as long as possible and the cross-sectional area should be small. Conversely, to increase the hydraulic radius of the flow channel, The peripheral length of the cross section may be made as short as possible so that the cross sectional area of the flow channel is increased. However, the means does not matter. First
As shown in FIG. 2 and FIG. 2, the wall thickness of the fin 2 is sequentially changed, and the hydraulic radius of the rectangular cross-sectional flow passage 21 on the side of the metal substrate 1 on which the heat-generating component 3 is attached is small, and the hydraulic radius increases every several steps as it goes downward. Alternatively, as illustrated in FIG. 3, the fins 2 may be formed to have the same thickness so that a portion near the heat-generating component 3 on the side of the metal substrate 1 is reduced.

In the radiator for electric elements of the present invention, a heat-generating component 3 such as a transistor is mounted on the metal substrate 1. Then, air or the like is naturally circulated from one side to the other inside each of the cross-section rectangular flow paths 21, 22, 23 of the fin 2, and the heat generated inside the heat generating component 3 is transmitted to the fin 2 through the metal substrate 1. It radiates heat. In the present invention, each cross-section rectangular channel 21 of the fin 2,
Of 22 and 23, the hydraulic radius of the cross-section rectangular flow passage 21 close to the heat-generating component 3 is smaller than the hydraulic radius of the cross-section square flow passage 22, and the hydraulic radius of the cross-sectional rectangular flow passage 22 is the farthest cross-section from the heat-generating component 3. Since it is formed to be smaller than the hydraulic radius of the rectangular flow path 23, the area can be increased by the amount corresponding to the reduction of the hydraulic radii, and hence the size is reduced. Further, in the case of the natural cooling type, the flow of the fluid is improved in the rectangular flow channel having the large difference between the fin temperature and the fluid temperature. Therefore, since the temperature of the fins 2 near the mounting position of the heat-generating component 3 rises higher than other parts, even if the hydraulic radius of the rectangular flow passage in the vicinity of the mounting position of the heat-generating component 3 is reduced, the fluid such as air is more likely to flow. Many flows and efficient heat exchange is performed.

[Effect of device]

As described above, according to the present invention, the fin material can be saved, and the radiator is an inexpensive and small natural cooling type electric element. Also,
Since more fluid flows in the rectangular flow path near the mounting position of the heat generating component, even if the hydraulic radius of the flow path near the mounting position of the heat generating component is smaller than other parts, the heat dissipation efficiency of the radiator as a whole is extremely high. It is a good radiator for electric elements.

[Brief description of drawings]

The drawings show an embodiment of a radiator for an electric device according to the present invention. FIG. 1 is a perspective view with one part cut away, FIG. 2 is a front view, and FIG. 3 is a front view showing another embodiment. is there. In the figure, 1 is a metal substrate, 2 is a fin, 3 is a heat-generating component, 21,
Reference numerals 22 and 23 denote flow channels having a rectangular cross section provided in the fin.

Claims (1)

[Scope of utility model registration request] 1. A natural cooling system in which a fin having a large number of rectangular cross-section flow paths is fixed to a metal substrate on which heat-generating components are mounted so that a fluid such as air naturally flows in each flow path of the fin. In the radiator for electric elements, a natural cooling type is characterized in that the hydraulic radius of the cross-section rectangular flow path of the fin is small near the mounting position of the heat-generating component and increases as it goes away from the mounting position. Radiator for electric elements.