JPS6014498A - Forcible air cooling heat sink unit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a forced air cooling radiator used by being attached to a housing of a heat generating element such as a power amplifier of a broadcasting transmitter.

Conventionally, this type of radiator has provided a part of the radiator fin with a cut extending in a direction perpendicular to the flow direction of the cooling air in order to reduce weight and improve the heat radiation effect.

As a result, turbulence noise was generated around the entire outer periphery of the heat dissipation fin, and the amount of heat dissipated was two to three times that of a laminar flow fin under the same conditions, and the heat dissipation fin was lighter by the amount of the cut. However, since it causes turbulence noise, under certain conditions (such as the pitch of the notch, the size of the fins, and the wind speed), resonance noise may be generated from the radiator.

FIG. 1 is a diagonal Dt diagram of a conventional lightweight forced air cooling radiator. A plate-shaped radiation fin 2 that stands up perpendicularly to the surface of the bottom plate 1
are installed in parallel. A large number of cuts (gaps) 5 are formed which pass in a direction perpendicular to the air flow 4 that cools the fins 2. Heat dissipation fin 2 is created by inserting a cut like this.
The air flow is forcibly disturbed by the air upstream end 21 and downstream end 22 of the air flow, and a vortex is generated in a wide range behind the flow.

FIG. 2 is a plan view showing a portion of the radiation fins and air flow shown in FIG. 1. FIG. The radiation fin 2 generates turbulent flow 6 not only at its upstream end 21 but also around the entire outer circumference, and has a turbulent flow 6 of 2 to 3 turbulent flow compared to laminar flow.
Double the amount of heat dissipated. Moreover, the heat dissipation fin becomes lighter by 50 minutes at the cut end.

However, due to the turbulent flow, certain conditions (
(values such as the pitch of the bonfire, the width of the fin, and the wind speed) had the disadvantage that resonance fragments were generated from the radiator and the noise was large.

An object of the present invention is to provide a strong ft1lJ air cooling radiator with low scratching noise.

The radiator for forced air cooling according to the present invention includes a large number of radiating fins arranged in a plurality of rows, a cooling air guide body that causes the entire cooling airflow to follow the radiating fins, and a cooling airflow guide that directs the entire cooling airflow along the radiating fins in the vicinity of some of the rows. The cooling air flow Hk is provided with means for differentiating the streamlines of the cooling air flow in the vicinity of the rows in other portions.

It is well known that noise is generated when airflow hits the heat dissipation fins in a duct. The generated sound is a pure tone, and the frequency increases with the airflow velocity, but the change is step-like. -tL, the frequency is almost close to the Karman vortex shedding frequency, which indicates that the sound generation phenomenon and the Karman vortex shedding are connected. The present invention is to reduce the discharge of Karman vortices and prevent the generation of stone chips by varying the flow of cooling air in all parts.5 Next, the present invention will be described in detail with reference to the drawings.

FIG. 3 is a perspective view of the first practical example of the present invention, in which seven wind leak prevention plates are provided at the tips of the fins.

As shown in this figure, by inserting one or more partition plates 8 between the fins, changing the shape, and making them a fitting for cooling air to flow between the vicinity of the partition plate 8 and the remaining parts, there is no resonance point. It is possible to prevent the generation of resonance noise. Also, instead of inserting a partition plate, the same effect can be obtained by not cutting out part of the fin metal.

FIG. 4 is a perspective view of a second practical example of the present invention. As shown in FIG. I'm here.

FIG. 5 is a perspective view of a modification of the second actual example in which a part of the chassis 10 of the device to be cooled is made of metal plate 9 in order to block the cooling air outlet; FIG. It is a perspective view of another modification of the second real sister example in which the cooling air outlet is blocked by the plate 9 by bending the entire extension of the IE plate 7.These modifications can also obtain the same effect as the previous embodiment. is clear.

As explained above, according to the present invention, it is possible to provide a radiator for forced air cooling that does not generate resonance noise and has low noise.

[Brief explanation of drawings]

Figure 1 is a perspective view of a conventional lightweight forced air cooling radiator;
The figure is a plan view showing part of the heat dissipation fins and the air flow shown in Fig. 1, Fig. 3 is a partially cutaway perspective view of the embodiment @l of the present invention, and Fig. 4 is a second actual sister of the present invention. FIGS. 5 and 6 are partially cutaway perspective views of the example, and FIGS. 5 and 6 are partially cutaway perspective views showing modifications of the second example, respectively. , heat dissipation fin, 4.
・Mark・Cooling air flow, 5...Gap between fins, 6・
Old... whirlpool, 7... river/wind leak prevention city board, 8... partition plate, 9... board, 100. . . . . Chassis, 21 . . . Air upstream end of the radiation fin 2, 22 . . . Air downstream end of the radiation fin 2. Agent Masashi Uchihara Shinkin 2nd Ward

Claims (1)

[Claims] A large number of radiation fins arranged in a plurality of rows, a cooling air guide body that guides the cooling air flow along the radiation fins, and a streamline of the cooling air flow in the vicinity of some of the rows; A radiator for forced air cooling comprising means for anisotropically interfering with the streamlines of the cooling air flow.