Double-layer structure for low-temperature Dewar and assembly method, disassembly method and temperature control method of double-layer structure

Abstract

The invention belongs to the technical field of precision measurement, and discloses a double-layer structure for a low-temperature Dewar and an assembly method, a disassembly method and a temperature control method of the double-layer structure. The double-layer structure comprises an outer sleeve, an inner sleeve and a sealing cover, an outer pipe joint is arranged on the outer sleeve, at least part of the outer pipe joint is located outside the low-temperature Dewar flask, and the outer pipe joint is connected with the low-temperature Dewar flask in a sealed mode so that the outer sleeve can be arranged in the low-temperature Dewar flask in a sealed mode; an inner pipe joint is arranged on the inner sleeve, at least part of the detection insertion rod is inserted into the inner sleeve, the detection insertion rod is used for detecting a sample, the inner sleeve is inserted into the outer sleeve, the inner pipe joint is in sealed connection with the outer pipe joint, and refrigerants are placed in the outer sleeve and the inner sleeve; and the sealing cover hermetically covers the top end of the inner sleeve. By means of the double-layer structure, it is guaranteed that the detection inserting rod can stably conduct detection work, and damage to the detection inserting rod caused by sample replacement and rewarming can be prevented.

Description

Technical Field

[0001] The present invention relates to the field of precision measurement technology, and in particular to a double-layer structure for a low-temperature dewar, an assembly method thereof, a disassembly method thereof and a temperature control method thereof. Background Art

[0002] Cryogenic Dewar is widely used in a variety of precision measuring equipment because of its ability to maintain extremely low temperatures for a long time, to ensure that these devices can operate stably in ultra-low temperature environments. At present, a detection rod with an operating temperature below the liquid helium temperature range is usually inserted into a cryogenic Dewar filled with liquid helium, and a single-layer cavity is usually set to isolate the liquid helium and the detection rod.

[0003] However, the detection rod often needs to be pulled out of the low-temperature Dewar for sample replacement and other operations. In order to prevent the influence of large-scale temperature changes on the detection rod, in the prior art, one method is to first heat the low-temperature components on the detection rod for reheating, and then directly pull out the detection rod. However, due to uneven heating and other reasons, it is easy for the component area far away from the heat source to form condensed water when it contacts the air, which affects the life and working condition of the detection rod; another method is to pull out the single-layer cavity and the detection rod at the same time, which will cause the liquid helium in the low-temperature Dewar to contact with the air for a long time, which is easy to cause the liquid helium to volatilize and pollute, etc., which is not conducive to the recovery of liquid helium.

[0004] In addition, in precision measurement experiments, a heating component needs to be set up to keep the temperature at the sample position constant. The heating component is usually set on the probe of the detection rod, and the probe is used to conduct heat to control the temperature at the sample position to be constant. However, this type of heat conduction method has a temperature gradient, and there are differences in temperature between different heat conduction areas. In the experiment, this temperature difference will affect the accuracy of the measurement results.

[0005] Therefore, it is necessary to provide a double-layer structure for a low-temperature Dewar, an assembly method thereof, a disassembly method thereof, and a temperature control method thereof to solve the above problems. Summary of the invention

[0006] The purpose of the present invention is to provide a double-layer structure for a low-temperature Dewar, an assembly method thereof, a disassembly method thereof and a temperature control method thereof, so as to ensure that a detection plug can stably perform detection work, prevent damage to the detection plug caused by sample replacement and reheating, and prevent the cold source in the low-temperature Dewar from evaporating into the air; during disassembly, the rate and amplitude of increase of the air pressure in the inner sleeve can be reduced; during the temperature control process, the influence of the temperature gradient can be eliminated to ensure the accuracy of the measurement results.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] A double-layer structure for a low-temperature Dewar, comprising:

[0009] An outer sleeve, wherein the outer sleeve is provided with an outer pipe joint, wherein the outer pipe joint is at least partially located outside the cryogenic Dewar, and the outer pipe joint is sealingly connected to the cryogenic Dewar so that the outer sleeve is sealingly arranged in the cryogenic Dewar;

[0010] An inner sleeve, wherein an inner pipe joint is provided on the inner sleeve, a detection rod is at least partially inserted in the inner sleeve, the detection rod is used to detect a sample, the inner sleeve is inserted in the outer sleeve, and the inner pipe joint is detachably connected to the outer pipe joint, and a refrigerant is placed in both the outer sleeve and the inner sleeve;

[0011] A sealing cover is arranged at the top end of the inner sleeve.

[0012] Preferably, the double-layer structure for the low-temperature Dewar further includes a temperature control unit, and the temperature control unit includes:

[0013] A heating component, the heating component is arranged at the bottom of the inner sleeve;

[0014] A temperature measuring component, which is arranged on the detection plug rod and is used to collect temperature information in the inner sleeve;

[0015] A temperature control component is communicatively connected with the heating component and the temperature measuring component.

[0016] Preferably, the temperature control unit further comprises a pressure measuring piece, which is used to collect the air pressure in the outer sleeve, and the pressure measuring piece is communicatively connected with the temperature control component.

[0017] Preferably, the temperature control component includes a main controller and a sub-controller which are communicatively connected, the main controller is communicatively connected to the temperature measuring component, and the sub-controller is communicatively connected to both the pressure measuring component and the heating component.

[0018] An assembly method of the double-layer structure for a low-temperature Dewar as described above comprises:

[0019] S1, inserting the outer sleeve into the low-temperature Dewar and fixing the two together;

[0020] S2, inserting the detection rod into the inner sleeve, installing the sealing cover on the top of the inner sleeve, and sealingly inserting the wiring end of the lead wire of the detection rod into the wiring hole of the inner sleeve;

[0021] S3, evacuating the inner sleeve through the inner pipe joint, inserting the inner sleeve into the outer sleeve and fixing the two together, and evacuating the outer sleeve through the outer pipe joint;

[0022] S4. Fill the inner sleeve with refrigerant through the inner pipe joint, and fill the outer sleeve with refrigerant through the outer pipe joint.

[0023] Preferably, a mounting piece is fixed on the detection rod, and after the detection rod is inserted into the inner sleeve, the mounting piece is fixedly connected to the inner pipe joint.

[0024] A disassembly method of the double-layer structure for a low-temperature Dewar as described above comprises:

[0025] S1, evacuating the refrigerant in the outer tube through the outer tube joint;

[0026] S2, disassembling the inner sleeve from the outer sleeve;

[0027] S3, connecting the exhaust pipe to the inner pipe joint, taking the inner sleeve out of the outer sleeve and keeping it for a set time;

[0028] S4. Evacuate the refrigerant in the inner sleeve through the inner pipe joint, disassemble the sealing cover and then take out the detection rod from the inner sleeve.

[0029] A temperature control method for a double-layer structure of a low-temperature Dewar as described above comprises:

[0030] S1, the temperature measuring component collects temperature information at the sample position and transmits the temperature information to the temperature control component;

[0031] S2, comparing the temperature information with the set temperature, and determining whether the temperature information deviates from the set temperature, if so, executing step S3;

[0032] S3. The temperature control component generates a control signal and outputs it to the heating component to control the operation of the heating component.

[0033] Preferably, the inner sleeve is made of heat-conducting material.

[0034] Preferably, in step S3, the temperature control component generates the control signal according to the temperature information and the collected air pressure information in the outer sleeve.

[0035] Preferably, the temperature control component includes a main controller and a sub-controller that are communicatively connected. In step S3, the main controller of the temperature control component generates an intermediate variable according to the temperature information, and the sub-controller of the temperature control component adjusts the intermediate variable according to the air pressure information to generate the control signal.

[0036] Beneficial effects of the present invention:

[0037] The present invention provides a double-layer structure used in a low-temperature dewar, the double-layer structure comprises an outer sleeve, an inner sleeve and a sealing cover, the outer sleeve is provided with an outer pipe joint, the outer pipe joint is at least partially located outside the low-temperature dewar, the outer pipe joint is sealed and connected to the low-temperature dewar so that the outer sleeve is sealed and arranged in the low-temperature dewar; the inner sleeve is provided with an inner pipe joint, a detection rod is at least partially inserted in the inner sleeve, the detection rod is used to detect samples, the inner sleeve is inserted in the outer sleeve, and the inner pipe joint is sealed and connected to the outer pipe joint, refrigerant is placed in both the outer sleeve and the inner sleeve; the sealing cover is arranged at the top of the inner sleeve.

[0038] The double-layer structure is arranged in the low-temperature dewar, which can not only provide the required ambient temperature for the detection plug placed in the double-layer structure during the low-temperature test, but also isolate the cold source and the detection plug in the low-temperature dewar, wherein the refrigerant placed in the inner sleeve and the outer sleeve can effectively transfer the low-temperature energy of the cold source, ensure that the detection plug can work normally in the test temperature zone, and prevent it from being damaged or affecting the detection accuracy due to temperature fluctuations; by arranging an outer pipe joint on the outer sleeve, the outer pipe joint is sealed and connected with the low-temperature dewar so that the outer sleeve is sealed and arranged in the low-temperature dewar, it can be ensured that the low-temperature dewar has good sealing performance, and the cold source therein will not contact the outside air; an inner pipe joint is arranged on the inner sleeve, and after the inner sleeve is inserted into the outer sleeve, the inner sleeve can be fixed in the outer sleeve through the sealing connection between the inner pipe joint and the outer pipe joint, which is simple and convenient to operate, and can prevent the refrigerant contained in the outer sleeve from leaking; a sealing cover is arranged at the top of the inner sleeve, so that the inner sleeve has good airtightness and prevents the refrigerant contained in the inner sleeve from leaking. When it is necessary to change the sample, the fixing relationship between the outer tube joint and the inner tube joint is released and the inner sleeve is pulled out, so that the detection plug rod is reheated in the inner sleeve. At this time, the detection plug rod will not contact the air to produce condensed water, and the outer sleeve is always sealed in the low-temperature Dewar, that is, the low-temperature Dewar is always in a sealed state, and the cold source inside it will not contact the air. Through this double-layer structure, it is ensured that the detection plug rod can perform detection work stably, and it can also prevent the damage to the detection plug rod caused by sample change and reheating.

[0039] The present invention provides a disassembly method for the above-mentioned double-layer structure for low-temperature Dewar, and the specific steps include: S1, evacuating the refrigerant in the outer sleeve through the outer pipe joint; S2, disassembling the inner sleeve from the outer sleeve; S3, after connecting the exhaust pipe with the inner pipe joint, taking out the inner sleeve from the outer sleeve and keeping it for a set time; S4, evacuating the refrigerant in the inner sleeve through the inner pipe joint, disassembling the sealing cover and taking out the detection rod from the inner sleeve.

[0040] The refrigerant in the outer sleeve is evacuated through the outer pipe joint to prevent the refrigerant in the outer sleeve from flowing into the air after the inner sleeve is removed and removed, thereby polluting the environment; the inner sleeve is removed from the outer sleeve, that is, the fixed connection between the inner pipe joint and the outer pipe joint is released; when the inner sleeve is removed, in order to allow the detection rod in the inner sleeve to return to room temperature faster and not be affected by condensed water, the refrigerant needs to be retained in the inner sleeve during the temperature recovery process. However, due to the increase in temperature, the air pressure in the inner sleeve will rise rapidly, which may damage the probe of the detection rod and other devices Parts, therefore, connect the exhaust pipe with the inner pipe joint and then take the inner sleeve out of the outer sleeve, and connect the inner sleeve with the exhaust pipe through the inner pipe joint, which can reduce the rate and amplitude of the increase of the air pressure in the inner sleeve, which can prevent the air pressure in the inner sleeve from rising sharply, and enable the detection rod to quickly return to temperature in the refrigerant environment, and the detection rod will return to room temperature after the set time; after the detection rod returns to room temperature, the refrigerant in the inner sleeve is evacuated through the inner pipe joint to prevent the refrigerant in the inner sleeve from flowing out into the air after the sealing cover is removed, causing pollution to the environment.

[0041] The present invention provides a temperature control method for a double-layer structure of a low-temperature Dewar, and the specific steps include: S1, a temperature measuring component collects temperature information at a sample position, and transmits the temperature information to a temperature control component;

[0042] S2. Compare the temperature information with the set temperature and determine whether the temperature information deviates from the set temperature. If so, execute step S3. S3. The temperature control component generates a control signal and outputs it to the heating component to control the operation of the heating component.

[0043] After the temperature measuring component collects the temperature information inside the inner sleeve in real time, the temperature information is transmitted to the temperature control component. The temperature control component compares the temperature information with the set temperature and determines whether the temperature information deviates from the set temperature. If it deviates, the temperature control component generates a control signal based on the temperature information and the set temperature and outputs it to the heating component to control the operation of the heating component. The heating component arranged at the bottom of the inner sleeve heats the inner sleeve so that the temperature at the sample position is at the set temperature. It can be understood that the set temperature is the test temperature zone. By controlling the heating component to ensure that the temperature at the sample position is constant, the temperature fluctuation is prevented from affecting the test conditions and the test results of the detection rod, and because the refrigerant has a convection effect, the influence of the temperature gradient can be effectively eliminated. In this embodiment, the temperature measuring component is arranged on the probe of the detection rod so as to accurately collect the temperature at the sample position arranged on the probe. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a cross-sectional view of a double-layer structure for a low-temperature Dewar provided by the present invention;

[0045] Figure 2It is a partial cross-sectional view of a double-layer structure for a low-temperature Dewar provided by the present invention;

[0046] Figure 3 It is a flow chart of the assembly method of the double-layer structure for the low-temperature Dewar provided by the present invention;

[0047] Figure 4 It is a flow chart of the disassembly method of the double-layer structure for low-temperature Dewar provided by the present invention;

[0048] Figure 5 The present invention provides a flow chart of a temperature control method for a double-layer structure of a low-temperature Dewar.

[0049] In the figure:

[0050] 100. Low temperature Dewar; 1001. Cover plate; 1002. Double-layer bottle body;

[0051] 1. Outer casing; 11. Outer pipe joint; 111. Outer pipe interface;

[0052] 2. Inner casing; 21. Inner pipe joint; 211. Inner pipe interface;

[0053] 3. Detection rod; 31. Lead wire; 311. Wiring terminal; 32. Probe;

[0054] 4. Sealing cover; 41. Wiring hole;

[0055] 5. Installation parts. DETAILED DESCRIPTION

[0056] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0057] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0058] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0059] In the description of this embodiment, the terms "upper", "lower", "right", etc., directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0060] Embodiment 1

[0061] At present, a detection rod with an operating temperature below the liquid helium temperature zone is usually inserted into a cryogenic dewar filled with liquid helium, and a single-layer cavity is usually set to isolate the liquid helium and the detection rod. However, the detection rod often needs to be pulled out of the cryogenic dewar for sample replacement and other operations. In order to prevent the influence of large-scale temperature changes on the detection rod, one method in the prior art is to first heat the low-temperature components on the detection rod for reheating, and then directly pull out the detection rod. However, due to uneven heating and other reasons, it is easy for the component area far away from the heat source to condense water when it contacts the air, which affects the life and working condition of the detection rod; another method is to pull out the single-layer cavity and the detection rod at the same time, which will cause the liquid helium in the cryogenic dewar to contact the air for a long time, which is easy to cause helium volatilization and pollution, etc., which is not conducive to the recovery of liquid helium.

[0062] To solve the above problems, Figure 1 , Figure 2As shown, this embodiment provides a double-layer structure for a low-temperature Dewar (hereinafter referred to as the double-layer structure), which includes an outer sleeve 1, an inner sleeve 2 and a sealing cover 4. The outer sleeve 1 is provided with an outer pipe joint 11, and the outer pipe joint 11 is at least partially located outside the low-temperature Dewar 100. The outer pipe joint 11 is sealed and connected to the low-temperature Dewar 100 so that the outer sleeve 1 is sealed and arranged in the low-temperature Dewar 100; the inner sleeve 2 is provided with an inner pipe joint 21, and the detection rod 3 is at least partially inserted in the inner sleeve 2, and the detection rod 3 is used to detect the sample. The inner sleeve 2 is inserted in the outer sleeve 1, and the inner pipe joint 21 is sealed and connected to the outer pipe joint 11, and refrigerant is placed in both the outer sleeve 1 and the inner sleeve 2; the sealing cover 4 is arranged at the top of the inner sleeve 2.

[0063] The double-layer structure is arranged in the low-temperature dewar 100, which can not only provide the required ambient temperature for the detection plug rod 3 placed in the double-layer structure during the low-temperature test, but also isolate the cold source in the low-temperature dewar 100 and the detection plug rod 3. The refrigerant placed in the inner sleeve 2 and the outer sleeve 1 can effectively transfer the low-temperature energy of the cold source, ensuring that the detection plug rod 3 can work normally in the test temperature zone and prevent it from being damaged or affecting the detection accuracy due to temperature fluctuations. By arranging an outer pipe joint 11 on the outer sleeve 1, the outer pipe joint 11 is sealed and connected to the low-temperature dewar 100 so that the outer sleeve 1 is sealed in the low-temperature dewar 100, which can ensure that the low-temperature dewar 100 has good sealing performance, and the cold source inside it will not contact the outside air; an inner pipe joint 21 is set on the inner sleeve 2, and after the inner sleeve 2 is inserted into the outer sleeve 1, the inner sleeve 2 can be fixed in the outer sleeve 1 through the sealing connection between the inner pipe joint 21 and the outer pipe joint 11, which is simple and convenient to operate, and can prevent the refrigerant contained in the outer sleeve 1 from leaking; the sealing cover 4 is set at the top of the inner sleeve 2, so that the inner sleeve 2 has good airtightness and prevents the refrigerant contained in the inner sleeve 2 from leaking. When it is necessary to change the sample, the fixing relationship between the outer pipe joint 11 and the inner pipe joint 21 is released and the inner sleeve 2 is pulled out, so that the detection plug rod 3 is reheated in the inner sleeve 2. At this time, the detection plug rod 3 will not contact the air to produce condensed water, and the outer sleeve 1 is always sealed in the low-temperature dewar 100, that is, the low-temperature dewar 100 is always in a sealed state, and the cold source inside it will not contact the air. This double-layer structure not only ensures that the detection rod 3 can stably perform detection work, but also prevents the detection rod 3 from being damaged by sample replacement and reheating.

[0064] It should be noted that the cold source is selected according to the test temperature zone required for testing the detection plug 3, and this embodiment does not limit this. In this embodiment, the cold source in the low temperature dewar 100 is liquid nitrogen.

[0065] Specifically, this double-layer structure also includes a temperature control unit (not shown in the figure), which includes a heating component, a temperature measuring component and a temperature control component. The heating component is arranged at the bottom of the inner sleeve 2, and the temperature measuring component is arranged on the detection plug 3. The temperature measuring component is used to collect temperature information in the inner sleeve 2, and the temperature control component is communicatively connected with the heating component and the temperature measuring component. The temperature in the double-layer structure can be actively adjusted by the temperature control unit so that the temperature at the sample position remains constant. The temperature measuring component measures and monitors the temperature information in the inner sleeve 2 in real time, and transmits the temperature information to the temperature control component. The temperature control component controls the heating component to heat according to the temperature information, so that the temperature in the inner sleeve 2 is constant and is in the test temperature zone of the detection plug 3.

[0066] Specifically, the temperature control unit also includes a pressure measuring piece, which is used to collect the air pressure in the outer sleeve 1, and the pressure measuring piece is connected to the temperature control component. The pressure measuring piece measures and monitors the pressure information in the outer sleeve 1 in real time, and transmits the pressure information to the temperature control component, and the temperature control component controls the heating component to heat according to the temperature information and pressure information. It can be understood that in the closed outer sleeve 1, the pressure information is the temperature information in the reaction outer sleeve 1, and the temperature fluctuation at the sample position comes from the temperature fluctuation in the inner sleeve 2 and the outer sleeve 1. The temperature is controlled only by the temperature information in the inner sleeve 2, which may be affected by the temperature fluctuation in the outer sleeve 1. The temperature fluctuations in the inner sleeve 2 and the outer sleeve 1 are considered together, and precise control can be performed.

[0067] In this embodiment, the temperature control component includes a main controller and a sub-controller that are communicatively connected, the main controller is communicatively connected to the temperature measuring component, and the sub-controller is communicatively connected to the pressure measuring component and the heating component. The main controller outputs an intermediate variable to the sub-controller based on the temperature information fed back by the temperature measuring component, and the sub-controller adjusts the intermediate variable based on the pressure information fed back by the pressure measuring component and outputs it to the heating component to control the heating power of the heating component, taking into account the temperature fluctuations in the inner sleeve 2 and the outer sleeve 1, so as to accurately control the temperature.

[0068] Embodiment 2

[0069] like Figure 1-Figure 3 As shown, this embodiment provides an assembly method of the double-layer structure for low-temperature Dewar described in Embodiment 1, and the specific steps include:

[0070] S1, insert the outer sleeve 1 into the low-temperature Dewar 100 and fix the two together;

[0071] S2, insert the detection rod 3 into the inner sleeve 2; install the sealing cover 4 on the top of the inner sleeve 2, and seal the wiring end 311 of the lead wire 31 of the detection rod 3 through the wiring hole 41 of the inner sleeve 2;

[0072] S3, evacuate the inner sleeve 2 through the inner pipe joint 21, insert the inner sleeve 2 into the outer sleeve 1 and fix the two together, and evacuate the outer sleeve 1 through the outer pipe joint 11;

[0073] S4. Fill the inner sleeve 2 with refrigerant through the inner pipe joint 21 , and fill the outer sleeve 1 with refrigerant through the outer pipe joint 11 .

[0074] The outer sleeve 1 is fixedly inserted into the low-temperature dewar 100 so that the outer pipe joint 11 seals the low-temperature dewar 100; after the detection rod 3 is inserted into the inner sleeve 2, the sealing cover 4 is installed on the top of the inner sleeve 2 so that the inner sleeve 2 is in a sealed state. Specifically, the sealing cover 4 is sealed and connected with the inner pipe joint 21 to achieve a sealed installation on the top of the inner sleeve 2; the wiring terminal 311 of the lead wire 31 of the detection rod 3 is sealed and inserted into the wiring hole 41 of the inner sleeve 2 to achieve mechanical connection and functional connection, and the wiring terminal 311 It can ensure air tightness and ensure that air will not enter the inner sleeve 2 through the wiring hole 41, so as to prevent water vapor and other components in the air from condensing in the inner sleeve 2 and damaging the detection rod 3; the inner sleeve 2 and the outer sleeve 1 are vacuumed respectively through the inner pipe joint 21 and the outer pipe joint 11, which can prevent water vapor in the air in the inner sleeve 2 from affecting subsequent detection, and the vacuum environment helps to improve the heat transfer efficiency of the refrigerant; the filling of the refrigerant can provide the necessary cooling effect. It should be noted that the selection and filling amount of the refrigerant are determined according to the test temperature zone of the detection rod 3.

[0075] Specifically, if Figure 1 and Figure 2 As shown, the cryogenic Dewar 100 includes a double-layer bottle body 1002 and a cover plate 1001. The cover plate 1001 is provided with an opening for inserting an outer sleeve 1. After the outer sleeve 1 is inserted into the cryogenic Dewar 100, the outer pipe joint 11 is located outside the cryogenic Dewar 100, and the outer pipe joint 11 is sealed and connected to the cover plate 1001.

[0076] It should be noted that if Figure 1As shown, the outer tube joint 11 is provided with an outer tube interface 111, which is connected to the outer sleeve 1, and the inner tube joint 21 is provided with an inner tube interface 211, which is connected to the inner sleeve 2. When vacuuming, the air extraction pipeline is connected to the outer tube interface 111 so that the air extraction pipeline is connected to the outer sleeve 1 to vacuumize the inside; the air extraction pipeline is connected to the inner tube interface 211 so that the air extraction pipeline is connected to the inner sleeve 2 to vacuumize the inside. When charging refrigerant, the charging pipeline is connected to the outer tube interface 111 so that the charging pipeline is connected to the outer sleeve 1 to charge refrigerant therein; the charging pipeline is connected to the inner tube interface 211 so that the charging pipeline is connected to the inner sleeve 2 to charge refrigerant therein. At other times, the inner tube interface 211 and the outer tube interface 111 are respectively blocked with sealing plugs to ensure good sealing of the inner sleeve 2 and the outer sleeve 1.

[0077] Specifically, Figure 2 As shown, a mounting member 5 is fixed on the detection rod 3. After the detection rod 3 is inserted into the inner sleeve 2, the mounting member 5 is fixedly connected to the inner pipe joint 21. The fixed connection between the mounting member 5 and the inner pipe joint 21 provides a stable support point for the detection rod 3, reducing the risk of loosening or displacement of the detection rod 3 due to vibration or external force; the fixed connection of the mounting member 5 makes it easier to disassemble and replace the detection rod 3 when changing samples, saving detection time.

[0078] Embodiment 3

[0079] like Figure 1 , Figure 2 and Figure 4 As shown, this embodiment provides a method for disassembling the double-layer structure for the low-temperature Dewar described in Embodiment 1, and the specific steps include:

[0080] S1, evacuating the refrigerant in the outer sleeve 1 through the outer pipe joint 11;

[0081] S2, disassembling the inner sleeve 2 from the outer sleeve 1;

[0082] S3, after the exhaust pipe is connected to the inner pipe joint 21, the inner sleeve 2 is taken out from the outer sleeve 1 and kept for a set time;

[0083] S4. The refrigerant in the inner sleeve 2 is evacuated through the inner pipe joint 21 , and the sealing cover 4 is disassembled to remove the detection rod 3 from the inner sleeve 2 .

[0084] The refrigerant in the outer sleeve 1 is evacuated through the outer pipe joint 11 to prevent the refrigerant in the outer sleeve 1 from flowing into the air after the inner sleeve 2 is disassembled and taken out, thereby polluting the environment; the inner sleeve 2 is disassembled from the outer sleeve 1, that is, the fixed connection between the inner pipe joint 21 and the outer pipe joint 11 is released; when the inner sleeve 2 is taken out, in order to enable the detection plug rod 3 in the inner sleeve 2 to recover to room temperature faster and not be affected by condensed water, the refrigerant needs to be retained in the inner sleeve 2 during the temperature recovery process. However, due to the increase in temperature, the air pressure in the inner sleeve 2 will rise rapidly, which may damage the probe 32 of the detection plug rod 3, etc. Device, therefore, the inner sleeve 2 is taken out from the outer sleeve 1 after the exhaust pipe is connected with the inner pipe joint 21, and the inner sleeve 2 is connected with the exhaust pipe through the inner pipe joint 21, which can reduce the rate and amplitude of the increase of the air pressure in the inner sleeve 2, which can prevent the air pressure in the inner sleeve 2 from rising sharply, and enable the detection rod 3 to quickly return to temperature in the refrigerant environment, and the detection rod 3 will return to room temperature after the set time; after the detection rod 3 returns to room temperature, the refrigerant in the inner sleeve 2 is evacuated through the inner pipe joint 21 to prevent the refrigerant in the inner sleeve 2 from flowing into the air after the sealing cover 4 is disassembled, causing pollution to the environment.

[0085] It should be noted that after the inner sleeve 2 is taken out, a sealing plug is used to seal the outer pipe joint 11 to prevent a large amount of condensed water from being generated on the inner wall of the outer sleeve 1 .

[0086] Embodiment 4

[0087] like Figure 1 , Figure 2 and Figure 5 As shown, this embodiment provides a temperature control method for the double-layer structure of the low-temperature Dewar described in Embodiment 1, and the specific steps include:

[0088] S1, the temperature measuring component collects the temperature information at the sample position and transmits the temperature information to the temperature control component;

[0089] S2, comparing the temperature information with the set temperature, and determining whether the temperature information deviates from the set temperature, if so, executing step S3;

[0090] S3. The temperature control component generates a control signal and outputs it to the heating component to control the operation of the heating component.

[0091] After the temperature measuring component collects the temperature information inside the inner sleeve 2 in real time, the temperature information is transmitted to the temperature control component. The temperature control component compares the temperature information with the set temperature and determines whether the temperature information deviates from the set temperature. If it deviates, the temperature control component generates a control signal based on the temperature information and the set temperature and outputs it to the heating component to control the operation of the heating component. The heating component arranged at the bottom of the inner sleeve 2 heats the inner sleeve 2 so that the temperature at the sample position is at the set temperature. It can be understood that the set temperature is the test temperature zone. By controlling the heating component to ensure that the temperature at the sample position is constant, the temperature fluctuation is prevented from affecting the test conditions and the detection results of the detection rod 3, and because the refrigerant has a convection effect, the influence of the temperature gradient can be effectively eliminated. In this embodiment, the temperature measuring component is arranged on the probe 32 of the detection rod 3 so that the temperature at the sample position arranged on the probe 32 can be accurately collected.

[0092] Specifically, the temperature control component also includes a host computer, which is used to set the set temperature.

[0093] In this embodiment, the material of the inner sleeve 2 is a heat-conducting material. The heating component is arranged at the bottom of the inner sleeve 2, and the inner sleeve 2 is made of a heat-conducting material so that the heat generated by the heating component can be transferred through the inner sleeve 2 and the refrigerant in the inner sleeve 2, so that the temperature at the sample position is constant, and because the refrigerant has a convection effect, it can effectively eliminate the influence of the temperature gradient, so that the temperature in different areas is the same, there will be no difference, and the test result is more accurate.

[0094] Exemplarily, the material of the inner sleeve 2 is a metal material such as copper, aluminum, iron, etc. It is understandable that any material with good thermal conductivity can be used to make the inner sleeve 2 in this embodiment, and this embodiment does not limit this.

[0095] Since the inner sleeve 2 is made of heat-conducting material, the temperature change of the refrigerant in the outer sleeve 1 will also be transmitted to the refrigerant in the inner sleeve 2 through the inner sleeve 2 to affect the temperature at the sample position, and when the heating component heats the refrigerant in the inner sleeve 2, the heat will also be transferred to the refrigerant in the outer sleeve 1. Therefore, the operation of the heating component is controlled only by the temperature information in the inner sleeve 2. Due to the interference of the refrigerant in the outer sleeve 1, the temperature after heating will still deviate from the set temperature, requiring multiple adjustments and controls, and the temperature control efficiency is low.

[0096] To solve the above problem, in the above step S3, the temperature control component generates a control signal based on the temperature information and the collected air pressure information in the outer sleeve 1. Since the outer sleeve 1 is in a sealed state, the air pressure information in it can indirectly reflect the temperature information in the outer sleeve 1. The temperature control component generates a control signal based on the temperature information in the inner sleeve 2 and the air pressure information in the outer sleeve 1 to control the heating of the heating component. By combining the temperature information and the air pressure information, the influence of the temperature fluctuation of the refrigerant in the outer sleeve 1 on the temperature at the sample position is reduced, and the temperature control efficiency can be improved.

[0097] Specifically, in the above step S3, the main controller of the temperature control component generates an intermediate variable according to the temperature information, and the sub-controller of the temperature control component adjusts the intermediate variable according to the air pressure information to generate a control signal. The temperature measuring component collects the temperature information and transmits it to the main controller. The main controller outputs the intermediate variable to the sub-controller based on the temperature information and the set temperature. The sub-controller generates a control signal based on the air pressure information and the intermediate variable to control the heating of the heating component. Through two-layer control, the tracking ability of the set temperature can be enhanced while maintaining the stability of the system; the main controller can ensure the overall stability of the temperature control, and the sub-controller can adjust the intermediate variable according to the air pressure information in the outer sleeve 1 to achieve precise control of the temperature.

[0098] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A double-layer structure for a low-temperature Dewar, characterized in that: include: An outer sleeve (1), the outer sleeve (1) being provided with an outer pipe joint (11), the outer pipe joint (11) being at least partially located outside the cryogenic dewar (100), the outer pipe joint (11) being sealingly connected to the cryogenic dewar (100) so that the outer sleeve (1) is sealingly arranged inside the cryogenic dewar (100); An inner sleeve (2), wherein an inner pipe joint (21) is provided on the inner sleeve (2), a detection rod (3) is at least partially inserted into the inner sleeve (2), the detection rod (3) is used to detect a sample, the inner sleeve (2) is inserted into the outer sleeve (1), and the inner pipe joint (21) is detachably connected to the outer pipe joint (11), and a refrigerant is placed in both the outer sleeve (1) and the inner sleeve (2); A sealing cover (4), wherein the sealing cover (4) is arranged at the top end of the inner sleeve (2).

2. The double-layer structure for low-temperature Dewar according to claim 1, characterized in that: The double-layer structure for the low-temperature Dewar also includes a temperature control unit, and the temperature control unit includes: A heating component, the heating component being arranged at the bottom of the inner sleeve (2); a temperature measuring element, the temperature measuring element being arranged on the detection plug rod (3) and being used to collect temperature information inside the inner sleeve (2); A temperature control component is communicatively connected with the heating component and the temperature measuring component.

3. The double-layer structure for low-temperature Dewar according to claim 2, characterized in that: The temperature control unit further comprises a pressure measuring piece, which is used to collect the air pressure in the outer sleeve (1), and the pressure measuring piece is communicatively connected with the temperature control component.

4. The double-layer structure for low-temperature Dewar according to claim 3, characterized in that: The temperature control component includes a main controller and a sub-controller which are communicatively connected. The main controller is communicatively connected to the temperature measuring component, and the sub-controller is communicatively connected to both the pressure measuring component and the heating component.

5. A method for assembling a double-layer structure for a low-temperature Dewar according to any one of claims 1 to 4, characterized in that: include: S1, inserting the outer sleeve (1) into the low-temperature Dewar (100) and fixing the two together; S2, inserting the detection plug rod (3) into the inner sleeve (2), installing the sealing cover (4) on the top of the inner sleeve (2), and sealingly inserting the wiring end (311) of the lead wire (31) of the detection plug rod (3) into the wiring hole (41) of the inner sleeve (2); S3, evacuating the inner sleeve (2) through the inner pipe joint (21), inserting the inner sleeve (2) into the outer sleeve (1) and fixing the two together, and evacuating the inner sleeve (1) through the outer pipe joint (11); S4. Fill the inner sleeve (2) with refrigerant through the inner pipe joint (21), and fill the outer sleeve (1) with refrigerant through the outer pipe joint (11).

6. The method for assembling a double-layer structure for a low-temperature Dewar according to claim 5, characterized in that: A mounting piece (5) is fixed on the detection rod (3); after the detection rod (3) is inserted into the inner sleeve (2), the mounting piece (5) is fixedly connected to the inner pipe joint (21).

7. A method for disassembling a double-layer structure for a low-temperature Dewar according to any one of claims 1 to 4, characterized in that: include: S1, evacuating the refrigerant in the outer sleeve (1) through the outer pipe joint (11); S2, disassembling the inner sleeve (2) from the outer sleeve (1); S3, connecting the exhaust pipe to the inner pipe joint (21), taking the inner sleeve (2) out of the outer sleeve (1) and keeping it for a set time; S4. The refrigerant in the inner sleeve (2) is evacuated through the inner pipe joint (21), and the sealing cover (4) is disassembled to remove the detection rod (3) from the inner sleeve (2).

8. A temperature control method for a double-layer structure of a low-temperature Dewar according to any one of claims 2 to 4, characterized in that: include: S1, the temperature measuring component collects temperature information at the sample position and transmits the temperature information to the temperature control component; S2, comparing the temperature information with the set temperature, and determining whether the temperature information deviates from the set temperature, if so, executing step S3; S3. The temperature control component generates a control signal and outputs it to the heating component to control the operation of the heating component.

9. The temperature control method for a double-layer structure of a low-temperature Dewar according to claim 8, characterized in that: The inner sleeve (2) is made of heat-conducting material.

10. The temperature control method for a double-layer structure of a low-temperature Dewar according to claim 9, characterized in that: In the step S3, the temperature control component generates the control signal according to the temperature information and the collected air pressure information in the outer sleeve (1).

11. The temperature control method for a double-layer structure of a low-temperature Dewar according to claim 10, characterized in that: In the step S3, the main controller of the temperature control component generates an intermediate variable according to the temperature information, and the sub-controller of the temperature control component adjusts the intermediate variable according to the air pressure information to generate the control signal.

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