Vibration reduction and heat insulation type low-temperature temperature control system

Abstract

The invention discloses a vibration reduction and heat insulation type low-temperature temperature control system, and relates to the technical field of low-temperature temperature control tests.A refrigeration unit comprises a lower cavity wall and a cold head, the refrigeration unit is connected to an external structure through a lower mounting part of the lower cavity wall, and a first-stage cold head of the cold head is provided with a cold head flange; the lower cavity wall and the cold head flange are connected through a first flexible corrugated pipe and jointly define a lower cavity heat insulation space surrounding the first-stage cold head and the second-stage cold head, a first heat exchanger connected with the second-stage cold head is arranged in the lower cavity heat insulation space, and a gaseous refrigerant enters the lower cavity heat insulation space through an input pipeline; and a gaseous refrigerant in the lower cavity heat insulation space exchanges heat with the second-stage cold head through the first heat exchanger and is converted into a liquid refrigerant, and the liquid refrigerant flows through the load, exchanges heat with the load and then enters the output pipeline. In the operation process of the system, high-frequency vibration impact energy generated by the cold head can be effectively isolated, and a plurality of heat insulation parts, loads and samples to be tested on the periphery of the cold head are protected.

Description

Technical Field

[0001] This application relates to the field of low-temperature temperature control testing technology, specifically to a vibration-damping and heat-insulating low-temperature temperature control system. Background Technology

[0002] In scientific research, materials testing, semiconductor processing, superconducting materials and other technical fields, it is crucial to accurately measure the physical properties (such as electrical, magnetic, and optical properties) of samples under low-temperature (e.g., 4K in the liquid helium range) and variable-temperature environments. Such tests typically employ a fixed-mount cold head to provide cooling to a load, with the sample placed on the load.

[0003] However, existing low-temperature temperature control systems of this type have many shortcomings. On the one hand, during the refrigeration process, the cold head generates vibrations and shocks during operation (such as compressor piston movement and cold head expansion and contraction). Since the cold head is usually rigidly connected to an external structure or related support components, this vibration and shock energy is directly transmitted to the entire system's installation structure and the surrounding environment. This not only affects the system's own stability and service life but may also interfere with vibration-sensitive loads or test samples, leading to deviations in the test results. For example, in some scenarios using high-precision optical paths for detection, vibrations exceeding the specified threshold may alter the optical path or cause sample displacement, affecting the accuracy of the detection. Furthermore, for systems that use refrigerant to exchange heat through the cold head to achieve load cooling, high-frequency vibrations and shocks can easily loosen the connections in the refrigerant pipelines, increasing the risk of refrigerant leakage. Simultaneously, they can induce refrigerant turbulence and pulses within the pipelines, affecting the stability of refrigerant delivery and heat exchange efficiency.

[0004] Therefore, there is room for improvement in existing low-temperature temperature control systems in terms of vibration reduction, and there is an urgent need for a low-temperature temperature control system that can effectively solve the above problems. Summary of the Invention

[0005] The present invention aims to provide a vibration-damping and heat-insulating low-temperature temperature control system, which overcomes the shortcomings of existing low-temperature temperature control systems in terms of vibration reduction, reduces the impact of vibration on the system and the sample under test, and improves the overall reliability and applicability of the system. The technical solution adopted in this application is as follows: A vibration-damping and heat-insulating low-temperature temperature control system includes a load, an input pipeline, an output pipeline, and a refrigeration unit. The refrigeration unit includes a lower cavity wall and a cold head. The lower cavity wall has a lower mounting portion, and the refrigeration unit is connected to an external structure through the lower mounting portion. The cold head includes a primary cold head and a secondary cold head. The primary cold head has a cold head flange. The lower cavity wall and the cold head flange are connected by a first flexible corrugated pipe and together define a lower cavity heat-insulating space surrounding the primary and secondary cold heads. A first heat exchanger connected to the secondary cold head is provided in the lower cavity heat-insulating space. Gaseous refrigerant enters the lower cavity heat-insulating space through the input pipeline to isolate the vibration generated by the cold head on the lower mounting portion by the flexible deformation of the first flexible corrugated pipe. The gaseous refrigerant in the lower cavity heat-insulating space exchanges heat with the secondary cold head through the first heat exchanger and is converted into liquid refrigerant. The liquid refrigerant flows through the load and exchanges heat with the load before entering the output pipeline.

[0006] In this technical solution, a new vibration reduction function is given to the gaseous refrigerant that is traditionally used only for heat exchange and refrigeration, realizing a dual function. The lower cavity insulation space is formed by connecting the lower cavity wall and the cold head flange of the first-stage cold head through the first flexible bellows. The first flexible bellows isolates the cold head from the lower cavity wall and constitutes the intermediate component for the cold head to transmit vibration to the lower cavity wall, thereby isolating the cold head from transmitting vibration to the lower cavity wall, significantly reducing the vibration transmitted to the external structure and environment, and effectively protecting the insulation components, load and sample under test around the cold head. Meanwhile, the gaseous refrigerant environment not only serves as a highly efficient vibration damping medium, but also, together with the first flexible corrugated pipe structure, constitutes an effective thermal insulation barrier. This significantly reduces the cold loss of the cold head and the intrusion of external heat, helping to maintain the stability and efficiency of heat exchange between the cold head and the gaseous refrigerant, thereby improving the stability of the low-temperature state in the load area and reducing energy consumption. In addition, this vibration reduction scheme directly reduces the risk of loose connections in the input and output pipes, as well as refrigerant turbulence and pulses caused by vibration, improving the stability of refrigerant delivery and heat exchange, and the reliability of the system. To achieve reliable isolation between the cold head and the lower cavity wall and to ensure the cold head is stable within the lower cavity insulation space, preferably, the cold head can be suspended on an external equipment structure or positioned using other suitable methods.

[0007] The vibration-damping and heat-insulating low-temperature temperature control system also includes a bracket, which is connected to the upper side of the cold head. In this technical solution, fixing the cold head with the bracket reduces the force on the first flexible bellows, significantly increases its lifespan, and enhances the stability of the entire system. Furthermore, the bracket can be directly installed on the external structure and separated from other components of the vibration-damping and heat-insulating low-temperature temperature control system to prevent the vibration of the cold head from being transmitted to other components, thereby further enhancing the vibration damping and isolation effect.

[0008] The bracket is connected to the upper side of the first-stage cold head via at least one of a damper, an elastic element, or an upper elastic buffer structure; or, the bracket is rigidly connected to the upper side of the first-stage cold head.

[0009] The upper elastic buffer structure includes a suspension mounting part and a lower connecting part located below the suspension mounting part. The suspension mounting part and the lower connecting part are connected by an elastic body. The first-stage cold head is fixedly connected to the lower connecting part, and the suspension mounting part is connected to the bracket.

[0010] In this technical solution, by adding an upper elastic buffer structure including a suspension mounting part, a lower connecting part, and an elastic body, and fixing the first-stage cold head to the lower connecting part, the upper elastic buffer structure can form an intermediate bridge structure connecting the cold head to the external equipment structure. The deformation of the elastic body provides additional vibration isolation effect, which can isolate and buffer the vibration energy transmitted from the cold head. The upper elastic buffer structure and the first flexible bellows form a bidirectional vibration reduction structure, further reducing the upward transmission of vibration through the suspension mounting part, enhancing the vibration suppression capability of the entire system, and is particularly helpful in isolating vibrations of different frequencies.

[0011] The elastic body is configured as a second flexible bellows. The suspension mounting part, the second flexible bellows, and the lower connecting part together define an upper cavity buffer space. A positive pressure environment is formed in the upper cavity buffer space by gaseous refrigerant, so as to use the compressibility of gaseous refrigerant and the flexible deformation of the second flexible bellows to isolate the vibration impact energy generated by the cold head on the suspension mounting part.

[0012] In this technical solution, the elastomer is specifically a second flexible bellows. This bellows, together with the suspension mounting part and the lower connecting part, forms an upper cavity buffer space. A positive pressure environment is created in this space by gaseous refrigerant. Combining the compressibility of the gaseous refrigerant and the flexible deformation of the second flexible bellows, an active and efficient vibration isolation mechanism is provided. This mechanism can more effectively dissipate the vibration impact energy generated by the cold head on the suspension mounting part, improving the vibration reduction performance of the upper buffer structure. At the same time, the bellows structure itself also has good sealing performance. The elastomer can adopt the same bellows structure as the first flexible bellows, preferably a bellows of the same material and structure. This ensures that when the vibration energy of the cold head is transmitted through the upper cavity buffer space and the lower cavity insulation space, its damping characteristics, resonant frequency, and energy dissipation mechanism are highly matched. This avoids vibration transmission phase differences or uncoordinated deformation caused by differences in structural types, significantly improving the overall isolation efficiency of high-frequency vibration energy and the system stability. Corrugated pipes of the same material and structure exhibit highly consistent coefficients of thermal expansion, thermal contraction, and low-temperature deformation characteristics under drastic temperature changes (such as cycling from 4K to room temperature). They can coordinate deformation synchronously, significantly reducing the risk of structural fatigue, sealing failure, or stress corrosion at connection points caused by thermal stress concentration, and enhancing the long-term reliability and lifespan of the system under extreme temperature environments.

[0013] The lower cavity insulation space and the upper cavity buffer space are connected by an airflow channel to achieve pressure balance, so that the pressure of the gaseous refrigerant working fluid acting on the cold head and its cold head flange can cancel each other out, so that the position of the cold head will not change with the change of refrigerant pressure.

[0014] The input pipe connects to the upper cavity buffer space, allowing gaseous refrigerant to enter at least one of the upper cavity buffer space and the lower cavity insulation space through the input pipe.

[0015] In this technical solution, the airflow channel connecting the lower insulation space and the upper buffer space helps to achieve pressure balance between the two chambers. An input pipeline is set to connect the upper buffer space, and the input pipeline supplies air to both the lower insulation space and the upper buffer space in a unified manner. This helps to simplify the system design and ensures that both the upper buffer space and the lower insulation space can obtain gaseous refrigerant to maintain the required positive pressure environment. Pressure balance helps to maintain the stable shape of the two flexible corrugated pipe structures, avoids stress or deformation caused by pressure difference, and enhances the overall stability of system operation and the reliability of vibration reduction and heat insulation effects.

[0016] A second heat exchanger is provided between the lower cavity wall and the primary cold head.

[0017] In this technical solution, a second heat exchanger is installed between the lower cavity wall and the primary cold head. This second heat exchanger is a non-contact type, capable of cooling the refrigerant through the primary cold head. In some cases, the cooled refrigerant can also transfer some of its cooling capacity to the lower cavity wall. This helps lower the temperature of the lower cavity wall, reducing radiative heat transfer from the environment to the insulated space through the lower cavity wall, thereby improving the system's insulation performance and increasing cooling capacity utilization efficiency. Lowering the temperature of the lower cavity wall reduces its thermal expansion stress, preventing structural deformation or sealing failure due to excessive internal and external temperature differences, thus extending the system's lifespan.

[0018] The load includes a third heat exchanger, a first cold shield, and a refrigerant pipeline connecting the third heat exchanger and the first cold shield. The first cold shield supports the third heat exchanger at intervals through a first insulation structure. The third heat exchanger is connected to the first heat exchanger, and the first cold shield is connected to the output pipeline, so that the liquid refrigerant discharged from the first heat exchanger first passes through the third heat exchanger to release its cooling capacity, then enters the first cold shield through the refrigerant pipeline to release its cooling capacity, and finally is output through the output pipeline.

[0019] In this technical solution, the liquid refrigerant flowing from the first heat exchanger sequentially flows through the third heat exchanger and the first cold shield to release its cooling capacity, achieving cascaded utilization of the cooling capacity. The liquid refrigerant releases its cooling capacity in the third heat exchanger, which is used to transfer cooling capacity to the sample for detection. A portion of the cooling capacity is further released into the first cold shield, which acts as a radiative heat shield layer to protect the core area of ​​the load, significantly reducing the impact of radiative heat load on the target low-temperature region and greatly improving the system's insulation effect and low-temperature maintenance capability. The first cold shield, through a first insulation structure, supports the third heat exchanger, reducing heat transfer between the first cold shield and the load, thus helping to maintain the load temperature in a stable state.

[0020] The vibration-damping and heat-insulating low-temperature temperature control system further includes a sealing wall and a second cold shield. The sealing wall is connected and cooperates with the lower mounting part to form a temperature control cavity capable of vacuuming. The temperature control cavity surrounds the load and the lower cavity wall. The second cold shield is disposed in the temperature control cavity. The second cold shield is connected and cooperates with the lower cavity wall and is arranged around the load. The inner wall of the second cold shield supports the first cold shield at intervals through a second heat insulation structure. The inner wall of the temperature control cavity supports the second cold shield at intervals through a third heat insulation structure.

[0021] In this technical solution, a vacuum-capable temperature-controlled cavity is formed by the cooperation of the sealing wall and the lower mounting part, and a second cold screen is set in the temperature-controlled cavity and supported by the second heat insulation structure and the sealing wall at intervals. The second cold screen surrounds the load and is supported by the first cold screen at intervals through the third heat insulation structure. This forms a multi-layer heat insulation structure composed of the sealing wall, the second cold screen, the first cold screen, the first heat insulation structure, the second heat insulation structure, and the third heat insulation structure arranged from the outside to the inside. Combined with the vacuum environment, it maximizes the isolation of external heat conduction, convection, and radiation, providing a stable ultra-low temperature environment for the load. At the same time, the design of the multi-level cold screen and heat insulation structure itself also has a certain vibration isolation and thermal isolation effect. Its stability is due to the core vibration reduction design of the upper cavity buffer space and the lower cavity heat insulation space, which effectively reduces the risk of vibration cracking of the sealing wall and ensures the vacuum heat insulation effect and detection accuracy.

[0022] The lower mounting part can be installed on the vibration isolation table to further isolate the vibration of the external environment.

[0023] A non-contact heat exchanger is installed between the secondary cold head and the lower cavity wall.

[0024] At least one of the input pipe and the output pipe is provided with a filter, and the filter is capable of filtering impurities in the refrigerant.

[0025] In this technical solution, the filter can effectively filter impurity particles that may be carried during the refrigerant circulation process, preventing these impurities from clogging the micro channels of the heat exchanger, wearing pump and valve components, or affecting the flow and heat exchange performance of the refrigerant. This ensures the long-term reliable operation of the refrigerant circulation system, reduces maintenance requirements, and thus indirectly maintains the stability of the system and the accuracy of low-temperature control.

[0026] The input pipeline and the output pipeline are connected by a circulation pump, which can pump the refrigerant flowing through the load back into the input pipeline; the vibration damping and heat insulation low temperature control system also includes a gas storage tank, which can replenish the refrigerant to the input pipeline or return the refrigerant output from the output pipeline.

[0027] In this technical solution, a closed-loop refrigerant circulation system is established by connecting the input and output pipelines through a circulating pump, realizing the recycling of refrigerant and improving refrigerant utilization and system energy efficiency. At the same time, an additional gas storage tank is added to replenish refrigerant to the input pipeline and supply refrigerant return flow. This allows the system to flexibly adjust the refrigerant pressure and total amount in the entire loop (including the lower cavity insulation space and the upper cavity buffer space) according to the operating status (such as load changes and temperature fluctuations), ensuring the stable maintenance of a positive pressure environment. This is crucial for vibration isolation and heat insulation effects, and improves the system's adaptability to different operating conditions and the accuracy of control. Attached Figure Description

[0028] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a schematic diagram illustrating the structural principle of the vibration-damping and heat-insulating low-temperature temperature control system provided in the embodiments of this application. Figure 1 ; Figure 2 This is a partial structural schematic diagram of the vibration-damping and heat-insulating low-temperature temperature control system provided in an embodiment of this application. Figure 3 This is a schematic diagram illustrating the structural principle of the vibration-damping and heat-insulating low-temperature temperature control system provided in the embodiments of this application. Figure 2 It uses arrows to indicate the circulation path of the refrigerant.

[0029] List of components and reference numerals: 10 Load, 101 Third heat exchanger, 102 First cold shield, 103 Refrigerant piping, 104 First insulation structure, 11 Inlet piping, 12 Outlet piping, 13 Lower cavity wall, 131 Lower mounting part, 14 First-stage cold head, 141 Cold head flange, 15 Second-stage cold head, 16 First flexible corrugated pipe, 17 Lower cavity insulation space, 18 First heat exchanger, 19 Suspension mounting part, 20 Lower connection part, 21 Insulation component, 22 Second flexible corrugated pipe, 23 Upper cavity buffer space 24 Second heat exchanger, 25 Refrigerant flow pipeline, 26 Throttling element, 27 Sealing wall, 28 Second cold shield, 29 Temperature control chamber, 30 Second insulation structure, 31 Third insulation structure, 32 Cold chain, 33 Filter, 34 Second filter, 35 Circulation pump, 36 Gas tank, 37 Refrigerant inlet / outlet control valve, 38 Gas tank connection pipeline, 39 Bypass pipeline, 40 Bypass valve, 41 Flow meter, 42 Needle valve, 43 Pressure gauge, 44 Safety valve, 45 Bracket. Detailed Implementation

[0030] To more clearly illustrate the overall concept of this application, a detailed explanation is provided below with reference to the accompanying drawings.

[0031] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.

[0032] Furthermore, it should be understood in the description of this application that the terms "upper," "lower," "top," "bottom," "inner," "outer," "axial," "radial," "circumferential," "lateral," and "longitudinal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0033] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0034] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0035] In the embodiments of this application, such as Figures 1 to 3 As shown, a vibration-damping and heat-insulating low-temperature temperature control system is provided. For ease of explanation and understanding, the following content provided in this application is based on the illustrated product structure. Of course, those skilled in the art will understand that the above structure is only a specific example and illustrative illustration, and does not constitute a specific limitation on the technical solution provided in this application.

[0036] like Figure 1As shown, the vibration-damping and heat-insulating low-temperature temperature control system includes a load 10, an input pipe 11, an output pipe 12, and a refrigeration unit. The refrigeration unit includes a lower cavity wall 13 and a cold head. The lower cavity wall 13 is provided with a lower mounting part 131. The refrigeration unit is connected to an external structure (such as a test bench, operating table, etc.) through the lower mounting part 131. The cold head includes a primary cold head 14 and a secondary cold head 15. The primary cold head 14 is provided with a cold head flange 141. The lower cavity wall 13 and the cold head flange 141 are connected by a first flexible corrugated pipe 16 and jointly define a lower cavity heat-insulating space 17 surrounding the primary cold head 14 and the secondary cold head 15. A first heat exchanger 18 connected to the secondary cold head 15 is provided in the lower cavity heat-insulating space 17. Gaseous refrigerant enters the lower cavity heat-insulating space 17 through the input pipe 11, which can form a positive pressure environment in the lower cavity heat-insulating space 17. There is no direct contact between the lower cavity walls 13 of the cold head, so that under the premise that there is a vibration at the level of hundreds of micrometers at the cold head, the vibration impact on other equipment can be reduced to the nanometer level. The gaseous refrigerant in the lower cavity insulation space 17 exchanges heat with the first heat exchanger 18 and the second-stage cold head 15 and is converted into liquid refrigerant. The liquid refrigerant flows through the load 10 and exchanges heat with the load 10 before entering the output pipeline 12.

[0037] In some cases, the first heat exchanger 18 can be a plug-in structure, including an upper heat exchanger connected to the secondary cold head 15 and a lower heat exchanger connected to the lower cavity wall 13. The upper heat exchanger and the lower heat exchanger are close to each other by fin plugging, and the refrigerant can flow between the upper heat exchanger and the lower heat exchanger to exchange heat with the secondary cold head 15.

[0038] In a preferred embodiment, the lower mounting portion 131 can be rigidly connected to the external structure via a flange structure. Specifically, the lower mounting portion 131 can be rigidly mounted on a vibration isolation platform to further isolate vibrations from the external environment. The outer edge of the cold head flange 141 of the first-stage cold head 14 can be machined with an annular groove. The two ends of the first flexible bellows 16 are respectively welded to the lower cavity wall 13 and the annular groove to form a sealed lower cavity heat insulation space 17. The first flexible bellows 16 is preferably made of stainless steel, such as 316L stainless steel, 304L stainless steel, etc., and can also be made of alloy materials, such as titanium alloy. In some cases, rubber, nylon, etc. can also be used to meet the core requirements such as ultra-low temperature toughness, high fatigue strength, low thermal conductivity, cold weld resistance, and vibration damping characteristics. The air inlet of the lower cavity insulation space 17 can be located on the cold head flange 141, the lower mounting part 131, or the lower cavity wall 13. The upper end of the first-stage cold head 14 can be exposed above the lower cavity insulation space 17 and is provided with an inlet for the refrigerant fluid required for the cold head to enter. The refrigerant fluid forms a low temperature in the first-stage cold head 14 and the second-stage cold head 15, and the low temperature heat is transferred to the first heat exchanger 18, where it exchanges heat with the gaseous refrigerant entering the first heat exchanger 18, and the gaseous refrigerant is converted into a low-temperature liquid refrigerant. In addition, in a preferred embodiment, a pressure sensor can also be installed at the outlet of the input pipe 11 or in the lower cavity insulation space 17 to monitor the air pressure in the lower cavity insulation space 17 in real time and feed it back to the external air source that delivers the gaseous refrigerant, ensuring that the positive pressure is controlled within a preset range.

[0039] In this technical solution, a new vibration reduction function is given to the gaseous refrigerant that is traditionally only used for heat exchange and refrigeration, realizing a dual-purpose device. The lower cavity wall 13 is connected to the cold head flange 141 of the first-stage cold head 14 through the first flexible bellows 16 to form the lower cavity insulation space 17. The first flexible bellows 16 isolates the cold head from the lower cavity wall 13 and constitutes the intermediate component between the cold head and the lower cavity wall 13. During the heat exchange and refrigeration process, the gaseous refrigerant establishes a positive pressure environment in the lower cavity insulation space 17. Combining the compressibility of the gaseous refrigerant and the flexible deformation of the first flexible bellows 16, the vibration impact energy generated by the cold head during operation on the lower mounting part 131 is effectively isolated, significantly reducing the vibration transmitted to the external structure and environment, and effectively protecting the insulation component 21, load 10 and the sample to be tested around the cold head. Meanwhile, this positive-pressure gaseous refrigerant environment not only serves as a highly efficient vibration damping medium, but also, together with the first flexible corrugated pipe 16 structure, constitutes an effective thermal insulation barrier. This significantly reduces the cold loss of the cold head and the intrusion of external heat, helping to maintain the stability and efficiency of heat exchange between the cold head and the gaseous refrigerant, thereby improving the stability of the low-temperature state in the load 10 area and reducing energy consumption. The positive-pressure gaseous refrigerant environment formed in the lower cavity insulation space 17 can also pressurize the liquid refrigerant into the refrigerant flow pipe 25, increasing the circulation efficiency of the liquid refrigerant. In addition, this vibration reduction scheme directly reduces the risk of loose connections, refrigerant turbulence, and pulses in the refrigerant pipes 103, such as the input pipe 11 and output pipe 12, caused by vibration, improving the stability of refrigerant delivery and heat exchange, as well as the reliability of the system.

[0040] In a preferred embodiment, the gaseous refrigerant can be helium, an inert gas capable of efficient cooling in the 4K temperature range, meeting the requirements for ultra-low temperature fluidity, chemical inertness, high thermal conductivity, and safety in use. In other alternative embodiments, the gaseous refrigerant can also be hydrogen, neon, or other suitable gases, which can be selected according to the specific needs of the detection scenario.

[0041] As one embodiment of this application, the vibration-damping and heat-insulating low-temperature temperature control system also includes a bracket 45, which is connected to the upper side of the cold head. This bracket reduces the force on the first flexible bellows 16, significantly increases the lifespan of the first flexible bellows 16, and enhances the stability of the entire system. Please refer to [link / reference]. Figure 1 The bracket 45 can be directly installed on the external structure and separated from other components of the vibration-damping and heat-insulating low-temperature temperature control system to prevent the vibration of the cold head from being transmitted to other components, thereby further enhancing the vibration reduction and isolation effect.

[0042] Regarding the connection method between the bracket 45 and the cold head, the cold head can be fixed directly by a rigid connection, or it can be connected by at least one of the following as intermediate elements: a damper, an elastic element, or an upper elastic buffer structure. It should be noted that when using a rigid connection or using elements such as a damper, an elastic element, or an upper elastic buffer structure to connect the cold head and the bracket 45, the bracket 45 can at least partially bear the weight of the cold head to reduce the force on the first flexible bellows 16.

[0043] As a preferred embodiment of this application, such as Figure 1 As shown, the vibration-damping and heat-insulating low-temperature temperature control system also includes an upper elastic buffer structure. This upper elastic buffer structure includes a suspension mounting part 19 and a lower connecting part 20 located below the suspension mounting part 19. The suspension mounting part 19 and the lower connecting part 20 are connected by an elastic body. The first-stage cold head 14 is fixedly connected to the lower connecting part 20. By fixing the first-stage cold head 14 to the lower connecting part 20, the upper elastic buffer structure can form an intermediate bridge structure connecting the cold head to the external equipment structure. Specifically, the suspension mounting part 19 can be fixed to the external equipment structure, such as the bracket 45, using bolts, flanges, etc. Since the first-stage cold head 14 is fixed to the lower connecting part 20, the deformation of the elastic body provides additional vibration isolation, which can isolate and buffer the vibration energy transmitted vertically from the cold head. This allows the upper elastic buffer structure and the first flexible bellows 16 to form a bidirectional vibration-damping structure, further reducing the upward transmission of vibration through the suspension mounting part 19, enhancing the vibration suppression capability of the entire system, and particularly helping to isolate vibrations of different frequencies. In a preferred embodiment, the end of the first-stage cold head 14 exposed above the lower cavity insulation space 17 can be fixedly connected to the lower connecting part 20 through the insulation component 21. The insulation component 21 (such as a support structure made of fiber composite material, a support structure made of ceramic matrix composite material, etc.) not only meets the function of cold head suspension, but also meets the requirements of ultra-low thermal conductivity, high mechanical strength, excellent low temperature toughness and vibration fatigue resistance.

[0044] This embodiment does not limit the structure of the elastomer; for example, a helical spring can be used. However, as a more preferred embodiment, such as... Figure 1As shown, the elastic body is configured as a second flexible bellows 22. The suspension mounting part 19, the second flexible bellows 22, and the lower connecting part 20 together define the upper cavity buffer space 23. A positive pressure environment is formed in the upper cavity buffer space 23 by gaseous refrigerant. The compressibility of the gaseous refrigerant and the flexible deformation of the second flexible bellows 22 are used to isolate the vibration impact energy generated by the cold head on the suspension mounting part 19, providing an active and efficient vibration isolation mechanism. This can more effectively dissipate the vibration impact energy generated by the cold head on the suspension mounting part 19, improving the vibration reduction performance of the upper buffer structure. At the same time, the bellows structure itself also has good sealing performance. In specific operation, the external air source can be controlled to simultaneously supply gaseous refrigerant to the upper cavity buffer space 23 and the lower cavity insulation space 17, so that the upper and lower buffers can work synchronously to reduce vibration. The elastomer adopts the same bellows structure as the first flexible bellows 16, preferably using the same material and structure. This ensures that the damping characteristics, resonant frequency, and energy dissipation mechanism of the cold head vibration energy are highly matched when it is transmitted through the upper cavity buffer space 23 and the lower cavity insulation space 17. This avoids vibration transmission phase differences or uncoordinated deformation caused by structural differences, significantly improving the overall isolation efficiency and system stability for high-frequency vibration energy. Under drastic temperature changes (such as cycling from 4K to room temperature), the bellows of the same material and structure exhibit highly consistent coefficients of thermal expansion, thermal contraction, and low-temperature deformation characteristics, allowing for synchronized deformation. This significantly reduces the risk of structural fatigue, sealing failure, or stress corrosion at connection points caused by thermal stress concentration, enhancing the long-term reliability and lifespan of the system in extreme temperature environments. Furthermore, the use of the same bellows structure as the first flexible bellows 16 allows for standardized production processes, molds, and testing standards, reducing manufacturing costs and supply chain complexity. Simultaneously, enhanced component interchangeability simplifies subsequent maintenance and spare parts management processes.

[0045] Furthermore, the lower cavity insulation space 17 and the upper cavity buffer space 23 are connected by an airflow channel to achieve pressure balance, so that the forces acting on the cold head and its cold head flange 141 by the gaseous refrigerant can cancel each other out, ensuring that the position of the cold head does not change with the refrigerant pressure. The input pipe 11 is connected to the upper cavity buffer space 23, allowing the gaseous refrigerant to enter at least one of the upper cavity buffer space 23 and the lower cavity insulation space 17 through the input pipe 11. By connecting the lower cavity insulation space 17 and the upper cavity buffer space 23 through the airflow channel and setting the input pipe 11 to connect the upper cavity buffer space 23, the input pipe 11 supplies gas to both the lower cavity insulation space 17 and the upper cavity buffer space 23. When the input pipe 11 supplies gas to the lower cavity insulation space 17, the airflow overflowing from the lower cavity insulation space 17 enters the upper cavity buffer space 23 through the airflow channel, gradually achieving pressure balance between the two cavities. This approach helps simplify system design while ensuring that both the upper cavity buffer space 23 and the lower cavity insulation space 17 receive a gaseous refrigerant supply to maintain the required positive pressure environment. Pressure balance helps maintain the stable shape of the two flexible bellows structures, avoids stress or deformation caused by pressure difference, and enhances the overall stability of system operation and the reliability of vibration reduction and heat insulation effects.

[0046] As a preferred embodiment of this application, such as Figure 1 As shown, a second heat exchanger 24 is provided between the lower cavity wall 13 and the first-stage cold head 14 to cool the refrigerant through the first-stage cold head 14. In some cases, the temperature of the lower cavity wall 13 can also be reduced by the refrigerant cooled by the first-stage cold head 14, reducing the radiative heat transfer from the environment to the lower cavity insulation space 17 through the lower cavity wall 13, thereby improving the system's insulation performance and increasing the efficiency of cooling capacity utilization. Simultaneously, the second heat exchanger 24 can be a non-contact heat exchanger, meaning that the heat exchange structures on the cold head and lower cavity wall can be interlocked, without direct contact, resulting in good heat exchange performance. The lack of direct contact between the lower cavity wall 13 and the first-stage cold head 14 also isolates vibration transmission. Lowering the temperature of the lower cavity wall 13 reduces its thermal expansion stress, preventing structural deformation or sealing failure due to excessive internal and external temperature differences, thereby extending the system's lifespan. To achieve both efficient heat conduction and prevent the cold head from directly transmitting vibrations to the lower cavity wall 13 in the second heat exchanger 24, in a preferred embodiment, the second heat exchanger 24 can adopt a non-rigid contact heat transfer structure. For example, a plug-in heat exchanger can be used, including multiple first heat exchange forks connected to the inner wall of the lower cavity wall 13 and multiple second heat exchange forks connected to the cold head (the first and second heat exchange forks can be made of rigid metal materials). The first and second heat exchange forks are arranged at intervals. The first and second heat exchange forks transfer cooling capacity through convective heat transfer of the gaseous refrigerant flowing between them. Furthermore, the separation between the first and second heat exchange forks effectively isolates vibration transmission.

[0047] As a preferred embodiment of this application, such as Figure 1 As shown, the load 10 includes a third heat exchanger 101, a first cold shield 102, and a refrigerant pipeline 103 connecting the third heat exchanger 101 and the first cold shield 102. The first cold shield 102 supports the third heat exchanger 101 at intervals through a first insulation structure 104. The third heat exchanger 101 is connected to the first heat exchanger 18, and the first cold shield 102 is connected to the output pipeline 12, so that the liquid refrigerant discharged through the first heat exchanger 18 first passes through the third heat exchanger 101 to release its cooling capacity, and then enters the first cold shield 102 through the refrigerant pipeline 103 to release its cooling capacity, and finally is output through the output pipeline 12. Because the liquid refrigerant releases its cooling capacity by sequentially flowing through the third heat exchanger 101 and the first cold shield 102, a cascaded utilization of the cooling capacity is achieved. The liquid refrigerant releases its cooling capacity in the third heat exchanger 101, which is used to transfer cooling capacity from the third heat exchanger 101 to the sample, thereby keeping the sample at a low temperature for detection. Preferably, a cold-conducting detection stage for placing the sample can be provided on the third heat exchanger 101, through which the third heat exchanger 101 transfers its cooling capacity to the sample. After being discharged from the third heat exchanger 101, the refrigerant enters the first cold shield 102, where its cooling capacity is further released. The first cold shield 102 acts as a radiative heat shield layer, protecting the core area of ​​the load 10, significantly reducing the impact of radiative heat load on the target low-temperature area, and greatly improving the system's insulation effect and low-temperature maintenance capability. The first cold shield 102 supports the third heat exchanger 101 at intervals through the first insulation structure 104, reducing heat transfer between the first cold shield 102 and the load 10, which helps maintain the temperature of the load 10 in a stable state. Based on the aforementioned embodiment using helium as the gaseous refrigerant, in a further preferred embodiment, a throttling element 26 (such as a JT valve or capillary tube) can be installed on the refrigerant flow pipeline 25 between the first heat exchanger 18 and the second-stage cold head 15. This allows the liquid refrigerant to be converted into superfluid helium through the throttling element 26 and flow into the third heat exchanger. Due to thermal radiation, heat conduction and leakage from the supporting structure, and the thermal load of the leads, a portion of the flowing superfluid helium evaporates and flows out as helium gas. The sample is directly thermally connected to the heat exchanger via oxygen-free copper with high thermal conductivity, cooling the sample to the 1.6K temperature range. The ultra-low temperature helium vapor formed by the evaporation of superfluid helium during heat exchange in the third heat exchanger 101 releases its cooling energy onto the sample, lowering the sample's minimum temperature and widening the controllable temperature range.

[0048] It should be noted that after the refrigerant undergoes heat exchange in the third heat exchanger 101 and releases its cooling capacity in the first cold screen 102, it enters the output pipe 12 in a gaseous state. At this point, the converted gaseous refrigerant can be transported back to the next heat exchange and cooling process through the input pipe 11, thus forming a cycle for operation.

[0049] As a preferred embodiment of this implementation, such as Figure 1 and Figure 2 As shown, the vibration-damping and heat-insulating low-temperature temperature control system also includes a sealing wall 27 and a second cold shield 28. The sealing wall 27 is connected and cooperates with the lower mounting part 131 to form a temperature control cavity 29 capable of vacuuming. The temperature control cavity 29 surrounds the load 10 and the lower cavity wall 13. The second cold shield 28 is disposed in the temperature control cavity 29. The second cold shield 28 is connected and cooperates with the lower cavity wall 13 and is arranged around the load 10. The inner wall of the second cold shield 28 supports the first cold shield 102 at intervals through the second heat insulation structure 30. The inner wall of the temperature control cavity 29 supports the second cold shield 28 at intervals through the third heat insulation structure 31. In this technical solution, the sealing wall 27 and the lower mounting part 131 cooperate to form a vacuum-capable temperature-controlled cavity 29, and a second cold shield 28 is set in the temperature-controlled cavity 29 and supported by the second heat insulation structure 30 and the sealing wall 27 at intervals. The second cold shield 28 surrounds the load 10 and supports the first cold shield 102 at intervals through the third heat insulation structure 31. This forms a multi-layer heat insulation structure composed of the sealing wall 27, the second cold shield 28, the first cold shield 102, the first heat insulation structure 104, the second heat insulation structure 30, and the third heat insulation structure 31 arranged from the outside to the inside. Combined with the vacuum environment, it maximizes the isolation of external heat conduction, convection, and radiation, providing a stable ultra-low temperature environment for the load 10. At the same time, the design of the multi-level cold shield and heat insulation structure itself also has a certain vibration isolation and thermal isolation effect. Its stability is due to the core vibration reduction design of the upper cavity buffer space 23 and the lower cavity heat insulation space 17, which effectively reduces the impact of the vibration of the sealing wall 27 on the sealing effect, ensuring the vacuum heat insulation effect and detection accuracy. Preferably, the specific forms of the first heat insulation structure 104, the second heat insulation structure 30, and the third heat insulation structure 31 are not limited. For example, they can all be support structures made of fiber composite materials or ceramic matrix composite materials. Specifically, the second cold shield 28 can be a closed structure surrounding the load 10, with gaps left on it, so that the gas inside the second cold shield 28 can be extracted from the gaps to the outside of the second cold shield 28 when vacuuming. After the temperature control cavity 29 is evacuated, both the inside and outside of the second cold shield 28 are in a vacuum state.

[0050] As a preferred embodiment of this implementation, such as Figure 1 and Figure 2As shown, a cold chain 32 connects the secondary cold head 15 and the third heat exchanger 101, enabling the secondary cold head 15 to transfer cooling capacity to the third heat exchanger 101 via the cold chain 32. In this technical solution, the addition of a cold chain 32 between the secondary cold head 15 and the third heat exchanger 101 provides a direct solid-state heat transfer path, allowing the cooling capacity of the secondary cold head 15 to be transferred to the third heat exchanger 101 more quickly and directly. This enhances the cooling capacity transfer efficiency between the secondary cold head 15 and the third heat exchanger 101, accelerates the cooling process of the load 10, and improves the response speed and control capability of the load 10's temperature. This is particularly beneficial for applications requiring rapid temperature changes or high-precision temperature control. Specifically, the cold chain 32 connects the secondary cold head 15 and the third heat exchanger 101. This can be achieved by connecting the cold chain 32 to the first heat exchanger 18 and then to the third heat exchanger 101, or by having the cold chain 32 pass through the lower cavity wall 13 and connect to the secondary cold head 15. Preferably, the cold chain 32 can be made of copper braid, which has high thermal conductivity and can prevent vibrations from the objects at both ends of the cold chain 32 from being transmitted through it, thereby ensuring the vibration isolation effect of the load 10.

[0051] As a preferred embodiment of this implementation, such as Figure 1 As shown, at least one of the inlet pipe 11 and the outlet pipe 12 is equipped with a filter 33, which can at least filter impurities in the refrigerant. The figure shows an embodiment where the inlet pipe 11 is equipped with a filter 33. The filter 33 can effectively filter impurity particles that may be carried during the refrigerant circulation process, preventing these impurities from clogging the micro-channels of the heat exchanger, wearing pump and valve components, or affecting the flow and heat exchange performance of the refrigerant. This ensures the long-term reliable operation of the refrigerant circulation system, reduces maintenance requirements, and thus indirectly maintains the system's stability and low-temperature control accuracy. In another preferred embodiment, where a throttling element 26 is provided in the refrigerant flow pipe 25 between the first heat exchanger 18 and the secondary cold head 15, a second filter 34 can also be provided in the refrigerant flow pipe 25. The second filter 34 is located upstream of the throttling element 26. Preferably, the filter 33 can adopt a filter element structure with a pre-sintered filter element and an electrostatic adsorption module. The pre-sintered filter element can intercept metal debris, and the electrostatic adsorption module can capture charged particles. Other materials can also be combined to meet corresponding filtration requirements. The second filter 34 can be used to filter hydrogen fixation, nitrogen fixation, and oxygen fixation.

[0052] As a preferred embodiment of this application, such as Figure 1As shown, the input pipeline 11 and the output pipeline 12 are connected by a circulation pump 35. The circulation pump 35 can pump the gaseous refrigerant, which is converted from liquid refrigerant after heat exchange through the load 10, back into the input pipeline 11. The vibration-damping and heat-insulating low-temperature temperature control system also includes a gas storage tank 36, which is used to replenish refrigerant to the input pipeline 11 or return the refrigerant output from the output pipeline 12. Specifically, a refrigerant inlet / outlet control valve 37 can be installed at the outlet of the gas storage tank 36. The refrigerant inlet / outlet control valve 37 is connected to the input pipeline 11 through the gas storage tank connecting pipeline 38, and the output pipeline 12 is connected to the refrigerant inlet / outlet control valve 37 through a bypass pipeline 39. A bypass valve 40 is installed on the bypass pipeline 39. In this embodiment, a closed-loop refrigerant circulation system is established by connecting the input pipeline 11 and the output pipeline 12 through the circulation pump 35, realizing the recycling of gaseous refrigerant, improving the refrigerant utilization rate and system energy efficiency, such as Figure 3 As shown, the refrigerant flow path in the system's cyclic operating mode is illustrated by arrows. In some cases, the liquid refrigerant can be converted into a gaseous state before being pumped into the input line 11 by the circulation pump 35. When the refrigerant inlet / outlet control valve 37 is open and both the needle valve 42 and the bypass valve 40 are closed, the output line 12 can return gaseous refrigerant to the gas storage tank 36 via the circulation pump 35 and the gas storage tank connection line 38; when the refrigerant inlet / outlet control valve 37 and the needle valve 42 are open and the bypass valve 40 is closed, the gas storage tank 36 can output gaseous refrigerant to the input line 11 via the gas storage tank connection line 38. Therefore, by utilizing the gas supply function of the gas storage tank 36, the system can flexibly adjust the pressure and total amount of gaseous refrigerant in the entire circuit (including the lower cavity insulation space 17 and the upper cavity buffer space 23) according to the operating status (such as load 10 changes, temperature fluctuations, and pressure status), ensuring the stable maintenance of the positive pressure environment. This is crucial for vibration isolation and heat insulation effects, and improves the system's adaptability to different operating conditions and the accuracy of control.

[0053] In a preferred embodiment, such as Figure 1 As shown, a flow meter 41, a needle valve 42, a pressure gauge 43, and a safety valve 44 can also be installed on the input pipeline 11. The flow meter 41 and the needle valve 42 regulate the flow rate of the gaseous refrigerant to match the heat load of the load 10. The pressure gauge 43 and the safety valve 44 monitor and protect the pipeline pressure in real time. The collaboration of multiple components ensures the high efficiency and safety of the circulation loop.

[0054] For any parts not mentioned in this application, existing technologies may be used or referenced.

[0055] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0056] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A vibration-damping and heat-insulating low-temperature temperature control system, characterized in that, include: load; Inlet piping; Output piping; A refrigeration unit includes a lower cavity wall and a cold head. The lower cavity wall is provided with a lower mounting part. The refrigeration unit is connected to an external structure through the lower mounting part. The cold head includes a primary cold head and a secondary cold head. The primary cold head is provided with a cold head flange. The lower cavity wall and the cold head flange are connected by a first flexible bellows and together define a lower cavity insulation space surrounding the primary cold head and the secondary cold head. A first heat exchanger connected to the secondary cold head is provided in the lower cavity insulation space. Gaseous refrigerant enters the lower cavity insulation space through the input pipeline to isolate the vibration generated by the cold head on the lower mounting part by utilizing the flexible deformation of the first flexible bellows. The gaseous refrigerant in the lower cavity insulation space exchanges heat with the secondary cold head through the first heat exchanger and is converted into liquid refrigerant. The liquid refrigerant flows through the load and exchanges heat with the load before entering the output pipeline.

2. The vibration-damping and heat-insulating low-temperature temperature control system according to claim 1, characterized in that, The vibration-damping and heat-insulating low-temperature temperature control system also includes a bracket, which is connected to the upper side of the cold head through at least one of a damper, an elastic element, and an upper elastic buffer structure, or the bracket is rigidly connected to the upper side of the cold head.

3. The vibration-damping and heat-insulating low-temperature temperature control system according to claim 2, characterized in that, The upper elastic buffer structure includes a suspension mounting part and a lower connecting part located below the suspension mounting part. The suspension mounting part and the lower connecting part are connected by an elastic body. The first-stage cold head is fixedly connected to the lower connecting part, and the suspension mounting part is connected to the bracket.

4. The vibration-damping and heat-insulating low-temperature temperature control system according to claim 3, characterized in that, The elastic body is configured as a second flexible bellows. The suspension mounting part, the second flexible bellows, and the lower connecting part together define an upper cavity buffer space. A positive pressure environment is formed in the upper cavity buffer space by gaseous refrigerant, so as to use the compressibility of gaseous refrigerant and the flexible deformation of the second flexible bellows to isolate the vibration impact energy generated by the cold head on the suspension mounting part.

5. The vibration-damping and heat-insulating low-temperature temperature control system according to claim 4, characterized in that, The lower cavity insulation space and the upper cavity buffer space are connected by an airflow channel to achieve pressure balance.

6. The vibration-damping and heat-insulating low-temperature temperature control system according to claim 1, characterized in that, A second heat exchanger is provided between the lower cavity wall and the first-stage cold head. The second heat exchanger is a non-contact heat exchanger.

7. The vibration-damping and heat-insulating low-temperature temperature control system according to claim 1, characterized in that, The load includes a third heat exchanger, a first cold shield, and a refrigerant pipeline connecting the third heat exchanger and the first cold shield. The first cold shield supports the third heat exchanger at intervals through a first insulation structure. The third heat exchanger is connected to the first heat exchanger, and the first cold shield is connected to the output pipeline, so that the liquid refrigerant discharged from the first heat exchanger first passes through the third heat exchanger to release its cooling capacity, then enters the first cold shield through the refrigerant pipeline to release its cooling capacity, and finally is output through the output pipeline.

8. The vibration-damping and heat-insulating low-temperature temperature control system according to claim 7, characterized in that, The vibration-damping and heat-insulating low-temperature temperature control system further includes a sealing wall and a second cold shield. The sealing wall is connected and cooperates with the lower mounting part to form a temperature control cavity capable of vacuuming. The temperature control cavity surrounds the load and the lower cavity wall. The second cold shield is disposed in the temperature control cavity. The second cold shield is connected and cooperates with the lower cavity wall and is arranged around the load. The inner wall of the second cold shield supports the first cold shield at intervals through a second heat insulation structure. The inner wall of the temperature control cavity supports the second cold shield at intervals through a third heat insulation structure.

9. The vibration-damping and heat-insulating low-temperature temperature control system according to claim 7, characterized in that, A non-contact heat exchanger is provided between the secondary cold head and the lower cavity wall.

10. The vibration-damping and heat-insulating low-temperature temperature control system according to any one of claims 1-9, characterized in that, The input pipeline and the output pipeline are connected by a circulation pump, which can pump the refrigerant flowing through the load back into the input pipeline; The vibration-damping and heat-insulating low-temperature temperature control system also includes a gas storage tank, which can replenish refrigerant to the input pipeline or return the refrigerant output from the output pipeline.

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