An optical mirror temperature uniformization structure based on cold shield radiation cover and flexible cold chain

Abstract

The present invention discloses a temperature-homogenizing structure for an optical mirror body based on a cold shield radiation cover and a flexible cold chain. The cooling and temperature field homogenization of a large-caliber optical mirror body are achieved through the uniform heat radiation of a low-temperature cold shield radiation cover and the heat conduction effect of a flexible cold chain. The method has the advantages of uniform heat flux density of radiation heat transfer and high heat conduction efficiency. It is suitable for cooling and temperature field homogenization of large-caliber mirror bodies of space remote sensing payloads and large-size components placed in ground vacuum containers.

Description

Technical Field

[0001] The present invention relates to situations where large-aperture mirror bodies of space remote sensing payloads need to be refrigerated and have strict requirements on temperature uniformity. The present invention is also suitable for situations where large-size components placed in vacuum containers need to be refrigerated and have requirements on temperature field uniformity. Specifically, the present invention relates to a structure that achieves cooling of cooled components and isothermalization of the temperature field through uniform heat radiation of a cold shield radiation cover and heat conduction of a flexible cold chain. Background Art

[0002] In order to reduce the background noise of the detection instrument of the space remote sensing payload, the optical system and its structure of the instrument need to be cooled. When the size of the optical mirror body is relatively large, the temperature gradient of the mirror body itself will cause thermal deformation, which will cause the optical mirror surface to deteriorate and affect the detection performance. For this reason, it is necessary to adopt an effective method to reduce the thermal deformation of the mirror body caused by the uneven temperature field distribution after the mirror body is cooled. The present invention adopts a temperature-homogenizing structure based on a cold shield radiation cover and a flexible cold chain for heat transmission to provide an effective solution to the above problem. Summary of the invention

[0003] An optical mirror body temperature equalization structure based on a cold shield radiation cover and a flexible cold chain, characterized in that it includes a cold shield radiation cover 1, a low-temperature heat pipe 2, an insulation component 3, a mounting base plate 4, an optical mirror body back plate 5, a large-aperture optical mirror body 6, a flexible cold chain 7, and an insulation multi-layer component 8.

[0004] The large-caliber optical mirror body 6 in the optical mirror body temperature equalization structure based on the cold shield radiation cover and the flexible cold chain is connected to the optical mirror body back plate 5, the optical mirror body back plate 5 is connected to the mounting base plate 4 through the heat insulation component 3, the large-caliber optical mirror body 6 and the optical mirror body back plate 5 are thermally connected through the flexible cold chain 7, the cold shield radiation cover 1 composed of the cold shield cover plate 1-1, the cold shield side wall 1-2, and the cold shield light hole 1-3 is thermally connected to the optical mirror body back plate 5, the hot ends of the three low-temperature heat pipes 2 are thermally connected to the cold shield cover plate 1-1, and the heat insulation multilayer component 8 is coated on the outside of the cold shield radiation cover 1 and the low-temperature heat pipe 2. The low-temperature heat pipe 2 transfers the cold energy of the cold source to the cold shield radiation cover 1, and the cold shield radiation cover 1 transfers the cold energy to the optical mirror body back plate 5, and the optical mirror body back plate 5 transfers the cold energy to the large-caliber optical mirror body 6 through its inner side wall 5-1 through the flexible cold chain 7. In order to maintain the low-temperature working conditions of the large-aperture optical mirror body 6, an insulation assembly 3 consisting of a connector 3-1, a thin-wall insulation support 3-2, and an insulation pad 3-3 is used between the optical mirror body back plate 5 and the mounting base plate 4 to reduce the heat conduction between the higher temperature mounting base plate 4 and the lower temperature optical mirror body back plate 5.

[0005] The cold shield radiation cover 1 is composed of a cold shield cover plate 1-1, a cold shield side wall 1-2, and a cold shield light hole 1-3. It is made of 2mm thick aluminum plate, and temperature equalization measures are adopted to improve the uniformity of the temperature field of the cold shield radiation cover 1 itself. The inner sides of the cold shield cover plate 1-1 and the cold shield side wall 1-2 are sprayed with a high infrared emissivity coating, and the outer surface is processed into a low infrared emissivity surface.

[0006] The low-temperature heat pipe 2 is a high-efficiency heat transfer component based on phase change heat transfer. There are three of them, and their cold ends are connected to the cold source to transfer the cold energy of the cold source to the hot end.

[0007] There are three thermal insulation components 3, which are composed of a connector 3-1, a thin-walled thermal insulation support 3-2, and a thermal insulation pad 3-3. The connector 3-1 is made of titanium alloy material, the thin-walled thermal insulation support 3-2 is a hollow thin-walled structure with low thermal conductivity, and the thermal insulation pad 3-3 is made of polyimide material.

[0008] The mounting base plate 4 is made of composite material and serves as the mounting reference and thermal boundary of the optical system.

[0009] The optical mirror body back plate 5 is made of high thermal conductivity material, and six groups of mounting interfaces are reserved on the inner side wall 5 - 1 as heat transfer contact surfaces.

[0010] The flexible cold chain 7 is made of forty layers of 0.1 mm high thermal conductivity graphite sheets stacked and processed using special tooling.

[0011] The heat-insulating multilayer assembly 8 is composed of a wire mesh, a double-sided aluminized polyester film and a polyimide film. The polyimide film is the innermost layer, and the rest are wire mesh and double-sided aluminized polyester film alternately placed, with a total of thirty groups of wire mesh and double-sided aluminized polyester film alternately laid.

[0012] The advantages of the present invention are:

[0013] 1. The flexible cold chain made of pyrolytic graphite sheets with high thermal conductivity has the advantages of lighter weight and lower heat transfer resistance under the same size conditions compared with the traditional cold chain made of copper, aluminum and other metal sheets;

[0014] 2. By evenly distributing six flexible cold chains on the back plate of the optical mirror body and the back of the large-diameter optical mirror body, efficient cold transmission and uniformity of cold distribution between the back plate of the optical mirror body and the large-diameter optical mirror body are achieved, thereby improving the uniformity of the temperature field of the mirror body;

[0015] 3 After the cold shield radiation cover is cooled by the temperature-uniform treatment, its high-emissivity inner surface is used to radiate uniform heat flow to the back of the large-aperture optical mirror body, thereby achieving the radiation cooling effect on the mirror body and improving the uniformity of the temperature field of the mirror body;

[0016] 4. The flexible cold chain can customize the flexible structure according to the needs of the space layout, reduce the stress transfer between the optical mirror back plate and the large-diameter optical mirror body, and eliminate the adverse effects of possible external stress on the mirror surface;

[0017] 5 The optical mirror body back plate and the mounting base plate are connected by a heat insulation component, which can effectively reduce the heat conduction from the mounting base plate to the low-temperature optical mirror body back plate, which is conducive to maintaining the mirror body in a low-temperature working state.

[0018] 6. Covering the outer surface of the cold shield radiation cover with a heat-insulating multi-layer component can effectively reduce the heat radiation of the external thermal environment to the low-temperature components in the cold shield radiation cover. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Attached Figure 1 The diagram shows a structure including a cold shield radiation cover, a low-temperature heat pipe, a thermal insulation assembly and a mounting base.

[0020] Attached Figure 2 This is the structural layout diagram of the six flexible cold chains in the cold shield radiation cover.

[0021] Attached Figure 3 A cutaway view of the entire assembly. DETAILED DESCRIPTION

[0022] The specific implementation of the optical mirror body temperature equalization structure based on the cold shield radiation cover and the flexible cold chain involved in the present invention is:

[0023] 1. Connect the heat insulation assembly to the end of the primary mirror back plate, adjust the installation accuracy of the three heat insulation assemblies according to the optical design requirements, and then connect the heat insulation assembly to the installation base plate.

[0024] 2. Cut 0.1mm thick graphite sheets according to the actual heat transfer requirements and design dimensions, and make a flexible cold chain according to the actual space layout requirements and actual installation interfaces;

[0025] 3. Connect the two ends of the flexible cold chain to the inner side wall of the optical mirror back plate and the back of the large-diameter optical mirror respectively;

[0026] 4. Connect the cold shield radiation cover to the optical mirror back plate with screws. To enhance the heat exchange effect between the two, place a thermal conductive film on the thermal contact surface to reduce the contact thermal resistance.

[0027] 5. Connect the three low-temperature channel heat pipes to the cold shield radiation cover for thermal conductivity;

[0028] 6. The cold shield radiation cover and the low-temperature heat pipe are covered with a thermal insulation multi-layer component.

Claims

1. An optical mirror body temperature equalization structure based on a cold shield radiation cover and a flexible cold chain, comprising a cold shield radiation cover (1), a low-temperature heat pipe (2), a heat insulation component (3), a mounting base plate (4), an optical mirror body back plate (5), a large-diameter optical mirror body (6), a flexible cold chain (7), and a heat insulation multi-layer component (8), characterized in that: The large-aperture optical mirror body (6) is connected to the optical mirror body back plate (5), the optical mirror body back plate (5) is connected to the mounting base plate (4) via a heat insulation component (3), the large-aperture optical mirror body (6) and the optical mirror body back plate (5) are heat-conductively connected via a flexible cold chain (7), a cold shield radiation cover (1) composed of a cold shield cover plate (1-1), a cold shield side wall (1-2), and a cold shield light hole (1-3) is heat-conductively connected to the optical mirror body back plate (5), the hot ends of the three low-temperature heat pipes (2) are heat-conductively connected to the cold shield cover plate (1-1), and a heat insulation multilayer component (8) is coated on the outside of the cold shield radiation cover (1) and the low-temperature heat pipe (2); The heat pipe (2) transfers the cold energy of the cold source to the cold shield radiation cover (1), and the cold shield radiation cover (1) transfers the cold energy to the optical mirror body back plate (5), and the optical mirror body back plate (5) transfers the cold energy to the large-diameter optical mirror body (6) through its inner wall (5-1) and the flexible cold chain (7). In order to maintain the low-temperature working conditions of the large-diameter optical mirror body (6), a heat insulation component (3) composed of a connecting piece (3-1), a thin-walled heat insulation support (3-2), and a heat insulation pad (3-3) is used between the optical mirror body back plate (5) and the mounting base plate (4) to reduce the heat conduction between the higher-temperature mounting base plate (4) and the lower-temperature optical mirror body back plate (5).

2. According to claim 1, an optical mirror body temperature equalization structure based on a cold shield radiation cover and a flexible cold chain is characterized in that: The cold shield radiation cover (1) is composed of a cold shield cover plate (1-1), a cold shield side wall (1-2), and a cold shield light hole (1-3), and is made of a 2 mm thick aluminum plate. Temperature equalization measures are adopted to improve the uniformity of the temperature field of the cold shield radiation cover (1). The inner sides of the cold shield cover plate (1-1) and the cold shield side wall (1-2) are sprayed with a high infrared emissivity coating, and the outer surfaces are processed into a low infrared emissivity surface.

3. According to claim 1, an optical mirror body temperature equalization structure based on a cold shield radiation cover and a flexible cold chain is characterized in that: The low-temperature heat pipe (2) is a high-efficiency heat transfer component based on phase change heat transfer, and has three pipes in total, the cold ends of which are connected to a cold source, so as to transfer the cold energy of the cold source to the hot end.

4. According to claim 1, an optical mirror body temperature equalization structure based on a cold shield radiation cover and a flexible cold chain is characterized in that: The thermal insulation components (3) are three in total and are composed of a connecting piece (3-1), a thin-walled thermal insulation support (3-2), and a thermal insulation pad (3-3). The connecting piece (3-1) is made of titanium alloy material, the thin-walled thermal insulation support (3-2) is a hollow thin-walled structure with low thermal conductivity, and the thermal insulation pad (3-3) is made of polyimide material.

5. According to claim 1, an optical mirror body temperature equalization structure based on a cold shield radiation cover and a flexible cold chain is characterized in that: The mounting base plate (4) is made of composite material and serves as the mounting reference and thermal boundary of the optical system.

6. According to claim 1, an optical mirror body temperature equalization structure based on a cold shield radiation cover and a flexible cold chain is characterized in that: The optical mirror body back plate (5) is made of a high thermal conductivity material, and six groups of mounting interfaces are reserved on its inner side wall (5-1) as a heat transfer contact surface.

7. According to claim 1, an optical mirror body temperature equalization structure based on a cold shield radiation cover and a flexible cold chain is characterized in that: The flexible cold chain (7) is made of forty layers of 0.1 mm high thermal conductivity graphite sheets stacked together.

8. According to claim 1, an optical mirror body temperature equalization structure based on a cold shield radiation cover and a flexible cold chain is characterized in that: The thermal insulation multilayer assembly (8) is composed of a wire mesh, a double-sided aluminized polyester film and a polyimide film, wherein the polyimide film is the innermost layer, and the rest are wire mesh and double-sided aluminized polyester film alternately placed, with a total of thirty groups of wire mesh and double-sided aluminized polyester film alternately placed.

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