JPH0232200B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Technical Field of the Invention The present invention relates to improving the cooling performance of a shield plate included in a radiation cooler that cools special parts such as infrared detectors mounted on an artificial satellite to an appropriate operating temperature. .

(b) Background of the technology Photon detectors such as Hg Cd Te are used in infrared detectors for infrared cameras mounted on recent satellites for resource exploration. Although these have high sensitivity and fast response speed, they cannot achieve the desired performance unless they are cooled to an ultra-low temperature of 100℃. However, in outer space, where a refrigerant such as liquid nitrogen cannot be used and there is no heat transfer medium, a radiation cooler is used to cool the space by radiating heat into outer space. ing. Therefore, with regard to radiation coolers, there is a strong demand for the development of a technology that can promptly reflect and emit heat rays incident from outer space to outer space without absorbing them, in addition to improving the heat radiation performance.

(c) Prior art and problems Figure 1 is a diagram for comprehensively explaining the configuration of a radiation cooler installed on an artificial satellite, and Figure 2 is a diagram for explaining a conventional radiation cooler. It is a diagram.

As shown in FIG.
an infrared detector 4 that receives infrared rays 10 emitted from the earth 1 and incident from the direction of arrow A through a mirror 3 attached to the satellite 2; The cooling body 5 is cooled by the cooling body 5, and the reflection plate 6 is formed to expand outward from the outer peripheral edge of the cooling body 5 toward the outer space 100 side and is equipped with a cooling surface 6'. It is formed to expand outward on the 100 side, and is composed of a shield plate 7 that covers the detector 4, the cooling main body 5, and the reflector plate 6. The shield plate 7 has a reflecting mirror surface 7' and is structured to reflect and emit the earth's radiant heat 8 incident from the direction of arrow B.

The function of each component will be explained below using FIGS. 1 and 2. The cooling main body 5 is disposed with the opposite side to which the infrared detector 4 is attached facing the outer space 100 side, and radiates heat to the outer space 100 at an environmental temperature of 4〓 by its self-cooling effect. to cool the detector 4. The reflecting plate 6 has a reflecting surface 6' and a cooling surface 6'', and has the function of reflecting heat rays incident from the outer space 100 side on the reflecting surface 6' and radiating them in the outer space 100 direction, and the cooling surface 6''. Therefore, the structure has a heat dissipation function to the outer space 100. Furthermore, when the earth's radiant heat 8 enters from the direction of arrow B, the shield plate 7 reflects it to the outer space 100.
It has a structure in which the infrared rays are emitted to the side and are not irradiated internally, especially to the cooling main body 5, and at the same time, the infrared detector 4,
It is formed to cover the cooling main body 5 and the reflection plate 6, and is provided to protect them from various types of interference light. The infrared detector 4 attached to the radiation cooler 50 configured as described above precisely detects and analyzes the infrared distribution of the earth 1, and various resources on the earth are explored. However, in such a conventional structure, the outgas 9 that gradually flows out from the internal insulation materials of the satellite body 2 and the radiation cooler 50 into the vacuum and ultra-low temperature (4〓) outer space 100 direction (arrow C direction) is On the surface of the reflective mirror surface 7' of the shield plate 7, the kinetic energy is absorbed as thermal energy and the particles adhere. Then, the reflective function of the reflective mirror surface 7' is inhibited,
A situation has arisen in which the reflection angle changes and the reflected light enters the cooling surface 6'', thereby degrading its cooling function.

(d) Purpose of the Invention The present invention has been made to correct the above-mentioned conventional drawbacks, and its purpose is to provide a structure for restoring the reflective function of the shield plate, which has been degraded due to the adhesion of outgas. .

(e) Structure of the Invention According to the present invention, the object is to include an infrared detector mounted on an artificial satellite to detect incoming infrared rays, and an infrared detector to which the detector is attached to detect incoming infrared rays. a cooling main body that cools the cooling main body; a reflecting plate extending outward from the outer peripheral edge of the cooling main body toward the outer space side; and a reflecting plate extending outward from the outer peripheral edge of the reflecting plate toward the outer space side; The shield plate has an outgas release heater attached to the outer surface of the expanded portion, and the outgas release heater is connected to the infrared detector. This is accomplished by providing a radiant cooler controlled by a heater-controlled power supply with a monitor to monitor for degradation in detection performance.

(f) Examples of the invention Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 3 is a diagram for explaining one embodiment of a radiation cooler structure according to the present invention. In this figure, the same parts as in the previous figure are given the same reference numerals. Since the present invention relates to a structural improvement of a component of a radiation cooler, this will be explained with emphasis.

As shown in the figure, the present invention is characterized in that an outgas release heater 20 is attached to the outer surface 7'' of the expanded portion of the shield plate 7 constituting the radiation cooler, and a heater control power source 30 for controlling the heater 20 is provided. In other words, if outgas 9 adheres to the reflective mirror surface 7' of the shield plate 7 and the reflective function of the mirror surface 7' deteriorates, or the direction of reflection is disturbed and the outgas 9 enters the cooling surface 6'' of the reflective plate 6. Thermal energy is accumulated in the shield plate 7 and the reflector plate 6, and the infrared detector 4
As the temperature inevitably rises and the detection performance of the infrared ray 10 decreases, the heater control power supply 30 equipped with a monitor to monitor this is activated and the heater 20 is energized.

When the temperature of the shield plate 7 rises temporarily due to this energization, the outgas 9 adhering to the reflective mirror surface 7' receives thermal energy from the reflective mirror surface 7' and undergoes intense molecular motion, and eventually It separates from above the reflecting mirror surface 7'. Then, so that heat is radiated from the high temperature part to the low temperature part, the outgas 9 separated from the reflecting mirror surface 7' is emitted toward the extremely low temperature of outer space 100. Due to the reflective mirror surface 7' whose function has been restored in this way, the earth's radiant heat 8 incident from the direction of arrow B, for example, is reflected by the mirror surface 7' and returns to the outer space 10.
0, and the incidence of heat rays on the cooling surface 6'' is also reduced, so the radiation cooler recovers its original cooling function.Thus, the conditions for cooling the infrared detector 4 to the optimum operating temperature (100〓) are established. Naturally, when the maintenance is completed, the power supply to the heater 20 is stopped.Since each of the figures used in the explanation so far is a side sectional view, the reflector plate 6, shield plate 7, etc. are shown only on the upper and lower sides. However, it goes without saying that all of these are four-sided structures: top, bottom, left, and right.

In this way, the radiation cooler of the present invention has the shield plate 7
When the outgas 9 adheres to the reflective mirror surface 7' and the function of the infrared detector 4 becomes obstructed, the outgas release heater 20 is energized to temporarily heat the reflective mirror surface 7' and remove the adhered outgas 9. It has a structure that emits light in 100 directions into outer space. If the present invention is applied to a simulation of a ground experiment, the temperature of the shield plate 7 housed in the space chamber can be freely controlled from the outside.

(g) Effects of the Invention As explained in detail above, the radiation cooler of the present invention eliminates outgas that inhibits the function of infrared detectors mounted on artificial satellites by installing a heater that releases the outgas into space. This has a great effect in that the function of the detector which has deteriorated due to adhesion can be accurately and quickly restored.

[Brief explanation of drawings]

Figure 1 is a diagram for comprehensively explaining the configuration of a radiation cooler installed on an artificial satellite, Figure 2 is a diagram for explaining a conventional radiation cooler, and Figure 3 is a diagram for explaining the radiation cooler of the present invention. It is a figure for explaining one example of a cooler structure. In the drawing, 1 is the earth, 2 is the artificial satellite, 3 is the mirror, 4 is the infrared detector, 5 is the cooling body, 6 is the reflector, 6' is the reflective surface, 6'' is the cooling surface, 7 is the shield plate, 7' 8 represents a reflecting mirror surface, 8 represents earth's radiant heat, 9 represents outgas, 10 represents infrared rays, 20 represents an outgas release heater, 30 represents a heater control power source, 50 represents a radiation cooler, and 100 represents outer space.

Claims (1)

[Claims] 1. An infrared detector mounted on an artificial satellite to detect incoming infrared rays, a cooling body to which the detector is attached and which cools it by heat radiation into outer space, and the cooling a reflector extending outward from the outer periphery of the main body towards outer space; and a reflector extending further outward towards outer space from the outer periphery of the reflector and covering the detector, the cooling main body, and the reflector. and a shield plate, the shield plate having an outgas release heater attached to the outer surface of the expansion forming part, and the outgas release heater serving as a monitor for monitoring a decrease in the detection performance of the infrared detector. A radiation cooler characterized in that it is controlled by a heater control power source comprising: