Non-directional high and low temperature heat transfer structure and high and low temperature thermostat using the structure

Abstract

The present invention discloses a non-directional high-low temperature heat transfer structure and a high-low temperature thermostat using the structure. The heat transfer structure comprises a rear insulation support (2), a thin-walled tube (3) and a front insulation support (5). The rear end of the rear insulation support (2) is fixedly connected to the cold head of a GM refrigerator (1), the front end of the rear insulation support (2) is fixedly connected to the rear end of the thin-walled tube (3), the front end of the thin-walled tube (3) is fixedly connected to the rear end of the front insulation support (5), and the front end of the front insulation support (5) is fixedly connected to a sample stage (6). Tantalum sheets are arranged between the connection surfaces of each component. The high-low temperature thermostat comprises the above-mentioned high-low temperature heat transfer structure, a GM refrigerator (1) and a sample stage (6). The high-low temperature heat transfer structure of the present invention adopts a multi-stage structure, can be placed in any direction, can be assembled and disassembled in sections and can be reused, can span the low temperature and high temperature zones, and has great significance for the development of ultra-low temperature technology.

Description

Technical Field

[0001] The present invention relates to the field of ultra-low temperature and high temperature technology, in particular to the field of material testing technology in a high temperature wide temperature range of -269°C to -700°C and above, and specifically to a non-directional high and low temperature heat transfer structure with high reliability and a high and low temperature thermostat using the structure. Background Art

[0002] With the continuous development of cryogenic technology, many materials need to be tested for their performance parameters at deep low temperatures and high temperatures. As a result, thermostats have received more and more attention, and a large number of vertical thermostats have appeared in major laboratories. However, due to many special restrictions, non-directional high and low temperature thermostats must be used. In this way, the support structure of the vertical one cannot be applied to the horizontal thermostat.

[0003] In addition, in order to improve the test efficiency, it is necessary to realize high and low temperature continuous testing. At the same time, according to different test schemes, the sample installation direction needs to be arbitrary. However, the existing related technologies have three problems: 1. In order to achieve high temperature, the low temperature performance is sacrificed and the test temperature zone is small; 2. Gas is used as the heat transfer medium, and the thermal resistance is controlled by controlling the gas pressure. The structure is complex and difficult to control; 3. Certain special materials are used, but because the material itself is very brittle, it can only be applied vertically. Summary of the invention

[0004] The purpose of the present invention is to provide a high and low temperature heat transfer structure with good thermal insulation effect, long-term stability, reliable support, and non-directionality with thermal insulation low temperature 4K and high temperature 800K, and a high and low temperature thermostat using the structure in order to solve the problems existing in the prior art.

[0005] The purpose of the present invention is to be solved by the following technical solutions:

[0006] A high and low temperature heat transfer structure, characterized in that: the high and low temperature heat transfer structure comprises a rear insulation support, a thin-walled tube and a front insulation support, wherein the rear end of the rear insulation support is fixedly connected to the cold head of a GM refrigerator, the front end of the rear insulation support is fixedly connected to the rear end of the thin-walled tube, the front end of the thin-walled tube is fixedly connected to the rear end of the front insulation support, and the front end of the front insulation support is fixedly connected to the sample stage; at least one layer of tantalum sheet is arranged between the connecting surface between the rear end of the rear insulation support and the cold head of the GM refrigerator, between the connecting surface between the front end of the rear insulation support and the rear end of the thin-walled tube, between the connecting surface between the front end of the thin-walled tube and the rear end of the front insulation support, and between the connecting surface between the front end of the front insulation support and the sample stage.

[0007] The rear insulation support is a structure with an arc-shaped steel pipe in the middle and circular flanges with screw holes at both ends of the arc-shaped steel pipe. The two ends of the rear insulation support are respectively fastened to the cold head of the GM refrigerator and the rear end of the thin-walled tube by screws; the rear insulation support is made of 316L stainless steel.

[0008] The thin-walled tube is a structure with a steel tube in the middle and circular flanges with screw holes at both ends of the steel tube. The two ends of the thin-walled tube are respectively fastened to the front end of the rear insulation support and the rear end of the front insulation support by screws; the thin-walled tube is made of 316L stainless steel.

[0009] The front insulation support is a structure with an arc-shaped steel pipe in the middle and circular flanges with screw holes at both ends of the arc-shaped steel pipe. The two ends of the front insulation support are respectively fastened to the front end of the thin-walled tube and the sample table by screws; the front insulation support is made of 316L stainless steel; and a square hole is opened on the arc-shaped steel pipe of the front insulation support.

[0010] A sapphire rod is arranged in the thin-walled tube, and both ends of the sapphire rod are respectively connected to the cold head and the sample stage of the GM refrigerator through oxygen-free copper soft connections; at least one layer of indium sheet is arranged between the connection surface of the cold head of the GM refrigerator and the oxygen-free copper soft connection, between the connection surface of the oxygen-free copper soft connection and the rear end of the sapphire rod, between the connection surface of the front end of the sapphire rod and the oxygen-free copper soft connection, and between the connection surface of the oxygen-free copper soft connection and the sample stage.

[0011] The oxygen-free copper soft connection includes a soft connection block and an L-shaped soft connection. The soft connection block is used to lock the two ends of the sapphire rod. The soft connection block is connected to the cold head and the sample table of the GM refrigerator through the L-shaped soft connection respectively, and at least one layer of indium sheet is arranged between the connection surfaces of the soft connection block and the L-shaped soft connection.

[0012] The soft connection block includes a rear end soft connection block and a front end soft connection block, the rear end soft connection block is used to lock the rear end of the sapphire rod, and at least one layer of indium sheet is arranged between the connection surface of the rear end soft connection block and the sapphire rod; the front end soft connection block is used to lock the front end of the sapphire rod, and at least one layer of indium sheet is arranged between the connection surface of the front end soft connection block and the sapphire rod.

[0013] The L-shaped flexible connection includes a rear-end L-shaped flexible connection and a front-end L-shaped flexible connection, the horizontal part of the rear-end L-shaped flexible connection is used to connect the cold head of the GM refrigerator and the vertical part of the rear-end L-shaped flexible connection is used to connect the flexible connection block; the horizontal part of the front-end L-shaped flexible connection is used to connect the sample table and the vertical part of the front-end L-shaped flexible connection is used to connect the soft connection block.

[0014] A high and low temperature thermostat, characterized in that: the high and low temperature thermostat has a high and low temperature heat transfer structure, the rear end of the high and low temperature heat transfer structure is fixedly connected to the cold head of a GM refrigerator, and the front end is fixedly connected to a sample stage, a low temperature sensor is provided on the cold head of the GM refrigerator; the low temperature sensor and the high temperature sensor are respectively arranged on the upper and lower surfaces of the sample stage.

[0015] The high and low temperature thermostat has two heat transfer paths. The first heat transfer path is from the GM refrigerator to the rear insulation support, through the rear insulation support to the thin-walled tube, through the thin-walled tube to the front insulation support, and finally to the sample stage; the second heat transfer path is from the GM refrigerator through the oxygen-free copper flexible connection to the sapphire rod set in the thin-walled tube, and then to the sample stage through the oxygen-free copper flexible connection at the other end of the sapphire rod.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] The high and low temperature heat transfer structure of the present invention adopts a multi-stage structure, can be placed in any direction, has a strong load-bearing capacity and is easy to install, and is convenient to disassemble. With clever structural design and appropriate coordination, the high and low temperature heat transfer structure can span both low temperature and high temperature zones, which is of great significance to the development of ultra-low temperature technology.

[0018] The high and low temperature heat transfer structure of the present invention solves the problem of sample installation direction limitation through the connection of multiple sections, and also solves the problem of low temperature cooling and high temperature insulation required by the high and low temperature thermostat, thus killing two birds with one stone. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Attached Figure 1 It is a structural schematic diagram of the high and low temperature thermostat of the present invention;

[0020] Attached Figure 2 A three-dimensional diagram of the high and low temperature heat transfer structure of the present invention connected to a sample stage;

[0021] Attached Figure 3 It is a plan view of the high and low temperature heat transfer structure of the present invention when it is connected to the sample stage;

[0022] Attached Figure 4 This is a cross-sectional view of the high and low temperature heat transfer structure of the present invention when connected to the sample stage.

[0023] Among them: 1—GM refrigerator; 2—rear insulation support; 3—thin-wall tube; 4—sapphire rod; 5—front insulation support; 6—sample table; 7—L-type soft connection; 71—front L-type soft connection; 72—rear L-type soft connection; 8—soft connection block; 81—front soft connection block; 82—rear soft connection block. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0025] like Figure 1-4 As shown: a high and low temperature heat transfer structure, the high and low temperature heat transfer structure includes a rear insulation support 2, a thin-walled tube 3 and a front insulation support 5, wherein the rear end of the rear insulation support 2 is fixedly connected to the cold head of the GM refrigerator 1, the front end of the rear insulation support 2 is fixedly connected to the rear end of the thin-walled tube 3, the front end of the thin-walled tube 3 is fixedly connected to the rear end of the front insulation support 5, and the front end of the front insulation support 5 is fixedly connected to the sample stage 6. The sample stage 6 is placed at the front end of the structure. The entire sample stage 6 is supported on the GM refrigerator 1 by the rigid high and low temperature heat transfer structure. The verticality of the mounting surface of the sample stage 6 is ensured by adjusting the position of the screws; at least one layer of tantalum sheet is arranged between the connection surface between the rear end of the rear insulation support 2 and the cold head of the GM refrigerator 1, between the connection surface between the front end of the rear insulation support 2 and the rear end of the thin-walled tube 3, between the connection surface between the front end of the thin-walled tube 3 and the rear end of the front insulation support 5, and between the connection surface between the front end of the front insulation support 5 and the sample stage 6, and the tantalum sheet plays a role in isolating high temperature.

[0026] like Figure 1-4 As shown: Further, a sapphire rod 4 is provided in the thin-walled tube 3, and the two ends of the sapphire rod 4 are respectively connected to the cold head of the GM refrigerator 1 and the sample stage 6 through oxygen-free copper soft connections; at least one layer of indium sheet is arranged between the connection surface of the cold head of the GM refrigerator 1 and the oxygen-free copper soft connection, between the connection surface of the oxygen-free copper soft connection and the rear end of the sapphire rod 4, between the front end of the sapphire rod 4 and the connection surface of the oxygen-free copper soft connection, and between the connection surface of the oxygen-free copper soft connection and the sample stage 6.

[0027] The sapphire rod 4 used in the high and low temperature heat transfer structure of the present invention has a high thermal conductivity at low temperatures, and can transfer cold to the sample on the sample stage 6, meeting the low temperature requirements of the sample; at high temperatures, the thermal conductivity of the sapphire rod 4 is very low, which isolates the heat and indirectly protects the cold head of the GM refrigerator 1. At the same time, considering that the material of the sapphire rod 4 is relatively brittle, in order to avoid deformation due to temperature rise and fall and damage due to horizontal force, a stainless steel thin-walled tube 3 is provided on its outer side to play a supporting role. The two ends of the sapphire rod 4 are respectively connected to the cold head of the GM refrigerator 1 and the sample stage 6 through oxygen-free copper soft connections, and are not directly subjected to force, thereby ensuring the safety and reliability of the sapphire rod 4 cooling structure.

[0028] like Figure 2As shown, the oxygen-free copper flexible connection includes a flexible connection block 8 and an L-shaped flexible connection 7. The flexible connection block 8 is used to lock the two ends of the sapphire rod 4. The flexible connection block 8 is connected to the cold head of the GM refrigerator 1 and the sample stage 6 through the L-shaped flexible connection 7, and at least one layer of indium sheet is arranged between the connection surfaces of the flexible connection block 8 and the L-shaped flexible connection 7. The indium sheet plays a role in increasing heat conduction. Specifically, the flexible connection block 8 includes a rear-end flexible connection block 82 and a front-end flexible connection block 81. The rear-end flexible connection block 82 is used to lock the rear end of the sapphire rod 4, and at least one layer of indium sheet is arranged between the connection surfaces of the rear-end flexible connection block 82 and the sapphire rod 4; the front-end flexible connection block 81 is used to lock the front end of the sapphire rod 4, and at least one layer of indium sheet is arranged between the connection surfaces of the front-end flexible connection block 81 and the sapphire rod 4. The L-shaped flexible connection 7 made of oxygen-free copper adopts an L-shaped structural design and has a threaded hole on it. The L-shaped flexible connection 7 includes a rear-end L-shaped flexible connection 72 and a front-end L-shaped flexible connection 71. The horizontal part of the rear-end L-shaped flexible connection 72 is used to connect the cold head of the GM refrigerator 1 and the vertical part of the rear-end L-shaped flexible connection 72 is used to connect the flexible connection block 8; the horizontal part of the front-end L-shaped flexible connection 71 is used to connect the sample table 6 and the vertical part of the front-end L-shaped flexible connection 71 is used to connect the flexible connection block 8.

[0029] like Figure 2 As shown, the rear insulation support 2 is made of 316L stainless steel, the middle of the rear insulation support 2 is an arc-shaped steel pipe, and the two ends of the arc-shaped steel pipe are circular flanges with screw holes. The two ends of the rear insulation support 2 are respectively fastened to the cold head of the GM refrigerator 1 and the rear end of the thin-walled tube 3 by screws.

[0030] like Figure 2 As shown, the thin-walled tube 3 is made of 316L stainless steel, the middle of the thin-walled tube 3 is a steel tube, and both ends of the steel tube are circular flanges with screw holes, and the two ends of the thin-walled tube 3 are respectively fastened to the front end of the rear insulation support 2 and the rear end of the front insulation support 5 by screws.

[0031] like Figure 2 As shown, the front insulation support 5 is made of 316L stainless steel, the middle of the front insulation support 5 is an arc-shaped steel pipe, and the two ends of the arc-shaped steel pipe are circular flanges with screw holes, and the two ends of the front insulation support 5 are respectively fastened to the front end of the thin-walled tube 3 and the sample table 6 by screws; a square hole is opened on the arc-shaped steel pipe of the front insulation support 5 to reduce the gravity of the front end without changing the structural strength, so that it can bear its own weight and the gravity of all parts without deformation.

[0032] like Figure 1As shown: a high and low temperature thermostat, which includes a high and low temperature heat transfer structure, the rear end of which is fixedly connected to the cold head of the GM refrigerator 1, and the front end is fixedly connected to the sample stage 6, and a low temperature temperature sensor is provided on the cold head of the GM refrigerator 1; the sample stage 6 is distributed at the front end of the high and low temperature heat transfer structure, and its outside is connected to the sample, and different samples are fixed by screws. The low temperature temperature sensor and the high temperature temperature sensor are respectively arranged on the upper and lower surfaces of the sample stage 6 for measuring the temperature of the sample stage 6, and a heating rod is arranged in the center of the sample stage 6 for controlling the temperature of the sample stage 6. The high and low temperature thermostat has two heat transfer paths. The first heat transfer path is from the GM refrigerator 1 to the rear insulation support 2, through the rear insulation support 2 to the thin-walled tube 3, through the thin-walled tube 3 to the front insulation support 5, and finally reaches the sample table 6; the second heat transfer path is from the GM refrigerator 1 to the rear end L-shaped flexible connection 72, through the rear end L-shaped flexible connection 72 to the rear end flexible connection block 82, through the rear end flexible connection block 82 to the sapphire rod 4, through the sapphire rod 4 to the front end flexible connection block 81, through the front end flexible connection block 81 to the front end L-shaped flexible connection 71, and finally reaches the sample table 6.

[0033] At low temperature of 4K, the heat transfer path 1 of the GM refrigerator 1 has a very small amount of heat transferred from the cold head through the high and low temperature heat transfer structure, which mainly plays a supporting role; the heat transfer path 2 has a very large amount of heat transferred from the cold head through the sapphire rod 4, which mainly plays a cooling role. At high temperature of 800K, the heat transfer path 1 of the GM refrigerator 1 has a very small amount of heat transferred from the cold head through the high and low temperature heat transfer structure, which mainly plays a supporting role and heat insulation role; the heat transfer path 2 has a very small amount of heat transferred from the cold head through the sapphire rod 4, which mainly plays a heat insulation role.

[0034] like Figure 1-4 As shown, the high and low temperature heat transfer structure is arranged between the GM refrigerator 1 and the sample table 6 of the high and low temperature thermostat to provide a support function, which includes a rear insulation support 2, a thin-walled tube 3, and a front insulation support 5. Each component is circular or arched and can be arranged horizontally or vertically on one side of the cold head of the GM refrigerator 1 as needed. Each structure is fixed by screws to facilitate disassembly and repeated positioning; the thin-walled tube 3 is distributed in the middle of the high and low temperature heat transfer structure, and a sapphire rod 4 is wrapped inside it. The left and right ends are connected to the rear insulation support 2 and the front insulation support 5 through flange surfaces and are fixed by screws.

[0035] like Figure 1-4As shown, on the basis of the heat transfer path 1 of the high and low temperature heat transfer structure, a heat transfer structure of the heat transfer path 2 is further added. The heat transfer structure includes a sapphire rod 4 located in a thin-walled tube 3. The left and right ends of the sapphire rod 4 are locked by a front soft connection block 81 and a rear soft connection block 82. The front soft connection block 81 and the rear soft connection block 82 are respectively fixed to the front L-shaped soft connection 71 and the rear L-shaped soft connection 82 by screws, and the front L-shaped soft connection 71 is used to connect the sample stage 6, and the rear L-shaped soft connection 72 is used to connect the cold head of the GM refrigerator 1. At low temperatures, the sapphire rod 4 acts as a conductor to transfer the cold of the cold head to the sample stage 6. At high temperatures, the sapphire rod 4 acts as an insulator to block the high temperature of the sample stage 6, reduce the heat transferred to the GM refrigerator 1, and play a protective role. The GM refrigerator 1 is distributed at the rear end of the high and low temperature heat transfer structure, and is externally connected to the rear insulation support 2 and the rear end soft connection block 82. It mainly provides sufficient cooling source for the sample on the sample table 6. At the same time, it serves as the relay point of the high and low temperature heat transfer structure, and all the structural weight of the front end is placed on it.

[0036] like Figure 1-4 As shown, the rigid structure of the high and low temperature heat transfer structure of the present invention is distributed on the upper side, and all the flexible connections are distributed on the lower side. The installation order of the high and low temperature heat transfer structure is from left to right and from top to bottom, first installing the rigid structure and then the flexible connection. All installations are screw-locked for easy adjustment and reuse.

[0037] The high and low temperature thermostat of the present invention is targetedly provided with a low temperature sensor and a high temperature sensor according to the different temperatures of the low temperature 4K and the high temperature 800K. With 300K as the boundary, the low temperature sensor is used for 4K to 300K; and the high temperature sensor is used for 300K to 800K. The high temperature sensor may not be removed during low temperature experiments, because the low temperature will not damage the high temperature sensor. The low temperature sensor must be removed during high temperature experiments, otherwise, the low temperature sensor will be burned, causing unnecessary losses.

[0038] The present invention is verified by using low temperature 4K and high temperature 800K. The high-low temperature heat transfer structure can play a supporting and cooling role at low temperature. The sapphire rod 4 timely and effectively transfers the coldness of the cold head of the GM refrigerator 1 to the sample stage 6, thereby improving the cooling efficiency of the GM refrigerator 1; the high-low temperature heat transfer structure can play a supporting and insulating role at high temperature. The sapphire rod 4 timely and effectively blocks the high-temperature heat of the sample stage 6 from being transferred to the cold head of the GM refrigerator 1, thereby protecting the cold head of the GM refrigerator 1. By arranging a low-temperature temperature sensor and a high-temperature temperature sensor, low-temperature and high-temperature measurements are achieved, thereby ensuring the accuracy of the working environment of the sample stage 6. The high-low temperature heat transfer structure can adjust the structure in time and facilitate disassembly and assembly through segmented combination, thereby ensuring that the structure can be reused and is easy to install.

[0039] The above embodiments are only for illustrating the technical idea of ​​the present invention, and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the present invention; any technology not involved in the present invention can be realized by existing technologies.

Claims

1. A high and low temperature heat transfer structure, characterized in that: The high-low temperature heat transfer structure comprises a rear insulation support (2), a thin-walled tube (3) and a front insulation support (5), wherein the rear end of the rear insulation support (2) is fixedly connected to the cold head of the GM refrigerator (1), the front end of the rear insulation support (2) is fixedly connected to the rear end of the thin-walled tube (3), the front end of the thin-walled tube (3) is fixedly connected to the rear end of the front insulation support (5), and the front end of the front insulation support (5) is fixedly connected to the sample stage (6); at least one layer of tantalum sheet is arranged between the connection surface between the rear end of the rear insulation support (2) and the cold head of the GM refrigerator (1), between the connection surface between the front end of the rear insulation support (2) and the rear end of the thin-walled tube (3), between the connection surface between the front end of the thin-walled tube (3) and the rear end of the front insulation support (5), and between the connection surface between the front end of the front insulation support (5) and the sample stage (6); The rear insulation support (2) is a structure with an arc-shaped steel pipe in the middle and circular flanges with screw holes at both ends of the arc-shaped steel pipe. The two ends of the rear insulation support (2) are respectively fastened to the cold head of the GM refrigerator (1) and the rear end of the thin-walled tube (3) by screws; the rear insulation support (2) is made of 316L stainless steel; A sapphire rod (4) is arranged in the thin-walled tube (3), and the two ends of the sapphire rod (4) can be connected to the cold head of the GM refrigerator (1) and the sample stage (6) respectively through oxygen-free copper flexible connections; at least one layer of indium sheet is arranged between the connection surface between the cold head of the GM refrigerator (1) and the oxygen-free copper flexible connection, between the connection surface between the oxygen-free copper flexible connection and the rear end of the sapphire rod (4), between the connection surface between the front end of the sapphire rod (4) and the oxygen-free copper flexible connection, and between the connection surface between the oxygen-free copper flexible connection and the sample stage (6).

2. The high and low temperature heat transfer structure according to claim 1, characterized in that: The thin-walled tube (3) is a structure in which a steel tube is in the middle and circular flanges with screw holes are formed at both ends of the steel tube. The two ends of the thin-walled tube (3) are respectively fastened to the front end of the rear insulation support (2) and the rear end of the front insulation support (5) by screws; the thin-walled tube (3) is made of 316L stainless steel.

3. The high and low temperature heat transfer structure according to claim 1, characterized in that: The front thermal insulation support (5) is a structure with an arc-shaped steel pipe in the middle and circular flanges with screw holes at both ends of the arc-shaped steel pipe. The two ends of the front thermal insulation support (5) are respectively fastened to the front end of the thin-walled tube (3) and the sample table (6) by screws; the front thermal insulation support (5) is made of 316L stainless steel; and the arc-shaped steel pipe of the front thermal insulation support (5) is provided with a square hole.

4. The high and low temperature heat transfer structure according to claim 1, characterized in that: The oxygen-free copper flexible connection comprises a flexible connection block (8) and an L-shaped flexible connection (7), wherein the flexible connection block (8) is used to lock the two ends of the sapphire rod (4), and the flexible connection block (8) is connected to the cold head of the GM refrigerator (1) and the sample stage (6) through the L-shaped flexible connection (7), and at least one layer of indium sheet is arranged between the connection surfaces of the flexible connection block (8) and the L-shaped flexible connection (7).

5. The high and low temperature heat transfer structure according to claim 4, characterized in that: The flexible connection block (8) comprises a rear end flexible connection block (82) and a front end flexible connection block (81); the rear end flexible connection block (82) is used to lock the rear end of the sapphire rod (4), and at least one layer of indium sheet is arranged between the connection surfaces of the rear end flexible connection block (82) and the sapphire rod (4); and the front end flexible connection block (81) is used to lock the front end of the sapphire rod (4), and at least one layer of indium sheet is arranged between the connection surfaces of the front end flexible connection block (81) and the sapphire rod (4).

6. The high and low temperature heat transfer structure according to claim 4, characterized in that: The L-shaped flexible connection (7) comprises a rear L-shaped flexible connection (72) and a front L-shaped flexible connection (71), wherein the horizontal portion of the rear L-shaped flexible connection (72) is used to connect to the cold head of the GM refrigerator (1) and the vertical portion of the rear L-shaped flexible connection (72) is used to connect to the flexible connection block (8); the horizontal portion of the front L-shaped flexible connection (71) is used to connect to the sample stage (6) and the vertical portion of the front L-shaped flexible connection (71) is used to connect to the flexible connection block (8).

7. A high and low temperature thermostat, characterized in that: The high and low temperature thermostat comprises a high and low temperature heat transfer structure as claimed in any one of claims 1 to 6, wherein the rear end of the high and low temperature heat transfer structure is fixedly connected to the cold head of the GM refrigerator (1), and the front end is fixedly connected to the sample stage (6).

8. The high and low temperature thermostat according to claim 7, characterized in that: The high and low temperature thermostat has two heat transfer paths. The first heat transfer path is from the GM refrigerator (1) to the rear insulation support (2), through the rear insulation support (2) to the thin-walled tube (3), through the thin-walled tube (3) to the front insulation support (5), and finally to the sample stage (6); the second heat transfer path is from the GM refrigerator (1) to the sapphire rod (4) arranged in the thin-walled tube (3) through the oxygen-free copper flexible connection, and reaches the sample stage (6) through the oxygen-free copper flexible connection at the other end of the sapphire rod (4).

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