JPS59156900A - Thermal louver - 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 [Field of the Invention] The present invention relates to a thermal louver which is a heat radiation control device for a spacecraft such as an artificial satellite.

[Prior art and its problems]

Generally, most of the surface of a spacecraft such as an artificial satellite is covered with a vacuum insulation material, and the other part is used as a heat dissipation surface. A heat radiation control device that can increase or decrease the amount of heat radiation depending on the amount of internal heat generation is mounted on a part or all of the heat radiation surface to keep the internal temperature constant. Thermal louver is one such heat radiation control device.

FIG. 1 shows a conventional thermal louver.

The blade 3, which is moved by the driving force of the bimetal 2 that operates at the temperature of the heat dissipation surface 1, acts like a blind.
The amount of heat dissipated is controlled by increasing or decreasing the area exposed toward space.

On the back side of the heat dissipation surface 1, a heat transfer element 5 for transmitting heat from the screw device 4 and electronic devices located at other positions is installed. Heat radiation surface 1
The blade 3 is made of a material such as silver Teflon, which has surface characteristics such as a low solar absorption rate and a high emissivity, and the entire surface of the blade 3 is made of an aluminum mirror surface with a very low emissivity. When the blade 3 is fully closed (FIG. 1(b)), the heat dissipation surface 1 is covered by the blade 3 and is in a thermally insulated state covered by a single metal plate having both mirror surfaces. When blade 3 is fully open (1st
In Figure (d)), the heat dissipation surface 1 is almost exposed and has a large amount of heat dissipation.

In the intermediate state (FIG. 1(C)), the heat radiation amount also shows an intermediate value, but the controllability during this period is dependent on the bimetal 2.

ing.

However, when using a bimetal as a temperature sensitive device, it is quite difficult to select the material and adjust its temperature sensitivity, which causes malfunction.

[Purpose of the invention]

The present invention improves on the above-mentioned drawbacks of bimetals and provides a bimetal louver that is easier and more reliable to control.

[Summary of the invention]

The present invention uses a two-way memory shape alloy in place of traditional bimetals. This two-way memory shape alloy is an alloy that can repeatedly undergo reversible shape changes above and below a certain transformation temperature simply by changing temperature. Therefore, by setting this transformation temperature as the set temperature for opening and closing the blade, the alloy can have the same effect as bimetal. In other words, the alloy is deformed so that the blade closes at low temperatures, and then deformed so that the blade opens fully at a certain set temperature. Then, at temperatures above the set temperature, the blades remain fully open, and at intermediate temperatures, the intermediate blades open and close.

The change is reversible.

[Effects of the invention j Because it takes advantage of the feature of the two-way memory shape alloy that it operates as a sharp temperature-sensitive device just by being deformed at the set temperature, it is more reliable than the conventional bimetal drive. This forms a highly flexible and easy-to-manufacture control device.

[Embodiments of the invention]

FIG. 2 shows an embodiment of the present invention.

The blade 3, which is moved by the driving force of the two-way memory shape alloy 6 that operates at the temperature of the heat dissipation surface 1, works like a blind to increase or decrease the area of the heat dissipation surface 1 that is exposed toward outer space, thereby increasing the amount of heat dissipation. It's in control. The two-way memory shape memory alloy 6 is deformed so that the blade 3 is fully open at a certain set temperature, and the blade 3 is fully closed at a low temperature. Since the opening and closing of 3 is reversible, it constitutes a thermal louver that is easy to manufacture and highly reliable.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram showing a conventional thermal louver, Figure 2 is a schematic diagram showing a conventional thermal louver.
The figure is a schematic diagram showing an embodiment of the invention. DESCRIPTION OF SYMBOLS 1... Heat radiation surface, 2... Bimetal, 3... Blade, 4... Electronic equipment 1.5... Heat transfer element, 6...
Two-way self-memory shape alloy. Figure 1 (61, n (b) (C) tb 2 C

Claims (1)

[Claims] This thermal louver is a heat dissipation control device for spacecraft, and is characterized by using a two-way memory shape alloy to control the driving force of the blade.