An adiabatic demagnetization refrigeration system and method that can be operated without vibration

Abstract

The application provides an adiabatic demagnetization refrigeration system capable of operating without vibration, and particularly relates to the field of low-temperature refrigeration technology, and the adiabatic demagnetization refrigeration system capable of operating without vibration comprises an adiabatic demagnetization module, a framework module and a pre-cooling module. The application sets a thermal switch between the adiabatic demagnetization module and the pre-cooling module to control the conduction of heat. When the thermal switch is closed, the adiabatic demagnetization module keeps a normal refrigeration mode, and when the thermal switch is disconnected and the pre-cooling refrigerator is stopped at the same time, the system can be switched to a refrigeration mode without vibration, mechanical vibration and electromagnetic interference are greatly reduced, and the high-end application demand is met. The system can realize the switching of the two refrigeration modes while keeping the structure of the traditional adiabatic demagnetization module, and the whole system has simple structure and strong operability.

Description

Technical Field

[0001] This invention relates to the field of cryogenic refrigeration technology, and in particular to an adiabatic demagnetizing refrigeration system and refrigeration method that can operate without vibration. Background Technology

[0002] With the development of cutting-edge scientific fields such as condensed matter physics, space measurement, and two-dimensional technology, the demand for cryogenic refrigeration is increasing. Cryogenic refrigeration technology is usually a refrigeration technology that obtains temperatures below 1K and provides a certain amount of cooling capacity. Currently, commonly used cryogenic refrigeration technologies mainly consist of adsorption refrigeration, dilution refrigeration, and adiabatic demagnetization refrigeration.

[0003] Adiabatic demagnetizing refrigeration (ADR), one of the earliest cryogenic refrigeration technologies, boasts advantages such as high efficiency, independence from gravity, and the availability of scarce helium-3 gas. It has become one of the most promising cryogenic refrigeration technologies for space applications. ADR relies on the magnetocaloric effect generated by paramagnetic materials changing with an external magnetic field. Its basic components include a magnetocaloric module, a magnet, a thermal switch, a heat sink, and a cold head. An ideal ADR operates in a reverse Carnot cycle between the heat sink temperature and the cooling temperature, involving isothermal magnetization, adiabatic demagnetization, isothermal demagnetization, and adiabatic magnetization. The magnetocaloric module is magnetized to a high temperature... Once the heat sink reaches a certain temperature, the thermal switch between the heat sink and the magnetocaloric module is closed. The magnetocaloric module undergoes isothermal magnetization, releasing magnetization heat to the heat sink until the upper limit of the target magnetic field is reached. The thermal switch between the heat sink and the magnetocaloric module is then disconnected. The magnetocaloric module undergoes adiabatic demagnetization and cools to the cooling temperature. Under heat load conditions, the demagnetization rate is controlled, allowing the magnetocaloric module to undergo isothermal demagnetization and generate cooling to maintain a constant heat load temperature. When the magnetic field temperature drops to the lower limit of the target magnetic field, the thermal switch remains open, allowing the magnetocaloric module to regenerate under adiabatic conditions. After heating back to the heat sink temperature, the above steps are repeated. However, in some practical applications, a strictly quiet, extremely low-temperature environment is required. For example, modern microscopes with spatial resolutions at the nanometer or even picometer level are highly sensitive to external vibrations, while the compressor unit and cold head of a mechanical 4K refrigerator can generate significant vibrations. Summary of the Invention

[0004] To address the issue of vibration generated by the refrigeration unit during refrigeration, this invention proposes an adiabatic demagnetizing refrigeration system and refrigeration method that can operate without vibration.

[0005] This invention is achieved through the following technical solution:

[0006] This invention proposes a vibration-free adiabatic demagnetizing refrigeration system comprising an adiabatic demagnetizing module, a frame module, and a precooling module, wherein:

[0007] The structural module includes a secondary cold screen fitted around the outside of the thermal insulation and demagnetization module;

[0008] The thermal insulation and demagnetization module includes a magnetic heating module, the bottom of which is connected to a load, and the magnetic heating module is connected to a heat sink via a second thermal switch.

[0009] The magnetocaloric module is connected to the suspension structure on both the upper and lower sides. The outer edge of the suspension structure is fixed to the upper and lower end faces of the magnetic shield. The magnetocaloric module is fixed to the middle of the annular superconducting magnet through the suspension structure. The magnetocaloric module does not contact the superconducting magnet.

[0010] The thermal insulation and demagnetization module includes the magnetic shield, and one side of the top of the magnetic shield is connected to the heat sink via a copper rod.

[0011] The heat sink is provided with a first thermal switch on one side of its top, and the secondary cold screen is also provided with a secondary cold plate on its top. The secondary cold plate is fixedly connected to the secondary cold screen. The heat sink is connected to the secondary cold plate through the first thermal switch, and the heat sink is fixed to the secondary cold plate through a low thermal conductivity support column.

[0012] The precooling module is located on top of the secondary cold tray and connected to the secondary cold tray.

[0013] Furthermore, it also includes a primary cold screen and a primary cold plate, wherein the primary cold screen is fitted over the secondary cold screen and the primary cold screen is fixedly connected to the primary cold plate.

[0014] Furthermore, the bottom of the primary cold plate is fixedly connected to the top of the secondary cold plate via a low thermal conductivity support column.

[0015] Furthermore, a secondary cold head is provided on one side of the bottom of the primary cold plate, the top side of the secondary cold head is connected to the primary cold plate, and a flexible connector is provided on one side of the bottom of the secondary cold head. The bottom of the secondary cold head is fixedly connected to the secondary cold plate through the flexible connector.

[0016] Furthermore, it also includes a vacuum hood and a sealing plate, wherein the vacuum hood is fitted over the outside of the primary cold shield, and the vacuum hood is fixedly connected to the sealing plate.

[0017] Furthermore, the bottom of the sealing disc is fixedly connected to the primary cold plate via a low thermal conductivity support column.

[0018] Furthermore, the bottom of the sealing plate is also provided with a primary cold head, which is located on the bottom of the sealing plate near the secondary cold head. The top of the primary cold head is connected to the sealing plate, and the bottom of the primary cold head is connected to the primary cold plate.

[0019] Furthermore, it also includes a pre-cooling refrigerator, the room temperature portion of which is located on the side of the sealing plate near the first-stage cold head, and the room temperature portion of the pre-cooling refrigerator is connected to the sealing plate.

[0020] Furthermore, a shock-absorbing bellows is provided between the pre-cooling refrigeration unit and the vacuum hood.

[0021] Furthermore, a refrigeration method for a vibration-free adiabatic demagnetizing refrigeration system includes a normal refrigeration mode and a vibration-free refrigeration mode, wherein the normal refrigeration mode includes the following steps:

[0022] The pre-cooling refrigeration unit starts to cool, closes the first and second thermal switches, and pre-cools the insulation and demagnetization module through the pre-cooling module;

[0023] After precooling to the heat sink temperature, the adiabatic demagnetization module operates. The magnetothermal module is magnetized while being cooled. Once the target magnetic field is reached, the second thermal switch is disconnected, followed by adiabatic demagnetization, isothermal demagnetization cooling, and adiabatic magnetization. Then, the second thermal switch is closed, and isothermal magnetization begins, entering the periodic cooling cycle. In this mode, the precooling refrigerator remains running continuously, and the first thermal switch remains closed, which is the normal cooling mode.

[0024] The vibration-free cooling mode includes the following steps:

[0025] The pre-cooling refrigeration unit starts to cool, closes the first and second thermal switches, and pre-cools the insulation and demagnetization module through the pre-cooling module;

[0026] After precooling to the heat sink temperature, the adiabatic demagnetization module operates. The magnetothermal module is magnetized and cooled simultaneously. Once the target magnetic field is reached, the second thermal switch and the first thermal switch are disconnected. At the same time, the precooling refrigerator stops running. The precooling module and the adiabatic demagnetization module are in a heat transfer disconnected state. The magnetothermal module performs adiabatic demagnetization and isothermal demagnetization refrigeration. In this mode, the precooling refrigerator is always stopped and the first thermal switch is always open, which is a vibration-free refrigeration mode.

[0027] The pre-cooling refrigerator restarts to begin cooling, closes the first and second thermal switches, and the insulation and demagnetization module begins operation. The magnetothermal module is magnetized and cooled simultaneously. Once the target magnetic field is reached, the second and first thermal switches are disconnected, and the pre-cooling refrigerator stops running, starting a new round of vibration-free cooling mode. Attached Figure Description

[0028] Figure 1 This is a structural diagram of the vibration-free adiabatic demagnetizing refrigeration system of the present invention;

[0029] Figure 2 This is a structural diagram of a traditional adiabatic demagnetizing refrigeration system.

[0030] In the diagram, the components are: thermal insulation and demagnetization module 1, magnetothermal module 11, load 12, second thermal switch 13, heat sink 14, suspension structure 15, magnetic shield 16, superconducting magnet 17, high thermal conductivity copper rod 18, frame module 2, secondary cold shield 21, secondary cold plate 22, primary cold plate 23, primary cold shield 24, vacuum hood 25, sealing plate 26, low thermal conductivity support column 27, precooling module 3, precooling refrigerator 31, primary cold head 32, secondary cold head 33, flexible connector 34, and first thermal switch 4.

[0031] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0032] To more clearly and completely illustrate the technical solution of the present invention, the present invention will be further described below with reference to the accompanying drawings.

[0033] Please refer to Figures 1-2 This invention proposes a vibration-free adiabatic demagnetizing refrigeration system, comprising an adiabatic demagnetizing module 1, a frame module 2, and a precooling module 3, wherein:

[0034] The structural module 2 includes a secondary cold shield 21 that is fitted over the outside of the thermal insulation and demagnetization module 1;

[0035] The thermal insulation and demagnetization module 1 includes a magnetic thermal module 11, the bottom of which is connected to a load 12, and the magnetic thermal module 11 is connected to a heat sink 14 through a second thermal switch 13.

[0036] The magnetic thermal module 11 is connected to the suspension structure 15 on both the upper and lower sides. The outer edge of the suspension structure 15 is fixed to the upper and lower end faces of the magnetic shield 16. The magnetic thermal module 11 is fixed to the middle of the annular superconducting magnet 17 through the suspension structure 15. The magnetic thermal module 11 does not contact the superconducting magnet 17.

[0037] The thermal insulation and demagnetization module 1 includes the magnetic shield 16, and one side of the top of the magnetic shield 16 is connected to the heat sink 14 through a high thermal conductivity copper rod 18.

[0038] A first thermal switch 4 is provided on one side of the top of the heat sink 14. The secondary cold shield 21 is fixed to the secondary cold plate 22 on the top. The heat sink 14 is connected to the secondary cold plate 22 through the first thermal switch 4. The heat sink 14 is fixed to the secondary cold plate 22 through the low thermal conductivity support column 27.

[0039] The precooling module 3 is located on top of the secondary cold plate 22 and connected to the secondary cold plate 22.

[0040] Specifically, the second thermal switch 13 and the first thermal switch 4 are used to control the conduction and disconnection of heat transfer. The precooling module 3 performs cooling, closes the first thermal switch 4 and the second thermal switch 13, and precools the adiabatic demagnetizing module 1 through the precooling module 3. When the precooling reaches the required temperature of the heat sink 14, the adiabatic demagnetizing module 1 operates, and the magnetothermal module 11 is magnetized and cooled at the same time. After reaching the target magnetic field, it enters the adiabatic demagnetizing process.

[0041] In normal cooling mode, the pre-cooling refrigerator 31 remains running, and the first thermal switch 4 is always closed. During the adiabatic demagnetization process, when the temperature of the magnetothermal module 11 drops to the cooling temperature, the second thermal switch 13 remains open, and the isothermal demagnetization cooling process begins, with a certain load 12 applied. When the magnetic field is reduced to zero, the first cooling cycle ends, and the second thermal switch 13 remains open, entering the adiabatic magnetization process. When the magnetothermal module 11 heats up to slightly above the temperature of the heat sink 14, the second thermal switch 13 is closed, and the magnetothermal module 11 isothermally magnetized, generating magnetization heat, which is released to the heat sink 14 through the second thermal switch 13. When the magnetothermal module 11 is magnetized to the maximum magnetic field, the periodic cooling process begins.

[0042] In some practical applications, a strictly quiet, extremely low-temperature environment is required, which necessitates stopping the pre-cooling refrigerator 31 for vibration-free cooling. If there is no thermal switch connecting the pre-cooling module 3 and the thermal insulation and demagnetization module 1, the pre-cooling module 3, which contains many metal components, can act as a heat conductor. The large amount of heat leakage from the high-temperature zone causes the heat sink 14 to heat up rapidly, and the superconducting magnet 17 will fail to function properly due to quenching failure, thus preventing the thermal insulation and demagnetization cooling process.

[0043] This application adds a first thermal switch 4 between the precooling module 3 and the insulation and demagnetizing module 1. The precooling refrigerator 31 stops running and the first thermal switch 4 is disconnected, cutting off the heat transfer between the precooling module 3 and the insulation and demagnetizing module 1. This allows the insulation and demagnetizing module 1 to maintain the load 12 at the cooling temperature for a longer period of time and provide a vibration-free environment. At the same time, high-power components such as the compressor and rotary valve in the precooling refrigerator stop running, greatly reducing electromagnetic interference.

[0044] The precooling module 3 performs cooling, closes the first thermal switch 4 and the second thermal switch 13, and precools the insulation and demagnetizing module 1 through the precooling module 3. When the precooling reaches the required temperature of the heat sink 14, the insulation and demagnetizing module 1 operates, and the magnetothermal module 11 is magnetized and cooled at the same time. After reaching the target magnetic field, it enters the vibration-free cooling mode.

[0045] In the vibration-free operation mode, the precooling refrigerator 31 remains stationary, and the first thermal switch 4 remains open. When the magnetothermal module 11 is cooled and simultaneously magnetized to the target magnetic field, the second thermal switch 13 and the first thermal switch 4 are disconnected, and the precooling refrigerator 31 stops operating. The precooling module 3 and the adiabatic demagnetizing module 1 are in a heat transfer disconnected state, and the magnetothermal module 11 undergoes adiabatic demagnetization. When the temperature of the magnetothermal module 11 drops to the cooling temperature, the second thermal switch 13 remains open, and the isothermal demagnetization cooling process begins, implementing vibration-free cooling for the load 12. When the isothermal demagnetization reaches zero magnetic field, the precooling refrigerator 31 restarts for cooling, the first thermal switch 4 and the second thermal switch 13 are closed, the adiabatic demagnetizing module 1 operates, and the magnetothermal module 11 is magnetized and cooled simultaneously. After reaching the target magnetic field, the second thermal switch 13 and the first thermal switch 4 are disconnected, and the precooling refrigerator 31 stops operating, initiating a new round of vibration-free cooling mode.

[0046] In one embodiment, Figure 2 Compared with the traditional thermal insulation and demagnetization refrigeration system, this application adds a first thermal switch 4 between the precooling module 3 and the thermal insulation and demagnetization module 1. The whole system has a simple structure, strong operability, and meets the more stringent requirements for ultra-low temperature refrigeration. At the same time, the first thermal switch 4 and the second thermal switch 13 can also accelerate the cooling rate.

[0047] Furthermore, it also includes a primary cold shield 24 and a primary cold plate 23. The primary cold shield 24 is fitted over the secondary cold shield 21, and the primary cold shield 24 and the primary cold plate 23 are fixedly connected.

[0048] The bottom of the primary cold plate 23 is fixedly connected to the top of the secondary cold plate 22 via a low thermal conductivity support column 27;

[0049] A secondary cold head 33 is provided on one side of the bottom of the primary cold plate 23. The top side of the secondary cold head 33 is fixedly connected to the primary cold plate 23. A flexible connector 34 is provided on one side of the bottom of the secondary cold head 33. The bottom of the secondary cold head 33 is connected to the secondary cold plate 22 through the flexible connector 34.

[0050] Specifically, the flexible connector 34 can reduce vibration. The flexible connector 34 is made of high-purity copper foil or copper braid. The bottom of the second cold head and the second-stage cold plate 22 are flexibly thermally connected through the flexible connector 34. The first-stage cold plate 23 and the second-stage cold plate 22 are both made of oxygen-free high-purity copper. The surface of the second-stage cold plate 22 is gold-plated. The gold plating treatment enhances the thermal contact of the 4K temperature zone components and prevents oxidation. The first-stage cold screen 24 and the second-stage cold screen 21 are made of polished aluminum and wrapped with multiple layers of heat insulation material to reduce radiative heat leakage. The low thermal conductivity support column 27 supports and connects the first-stage cold plate 23, the second-stage cold plate 22 and the heat sink 11. The low thermal conductivity support column 27 here is supported by a thin-walled stainless steel tube.

[0051] Furthermore, it also includes a vacuum cover 25 and a sealing plate 26. The vacuum cover 25 is fitted over the outside of the primary cold shield 24, and the vacuum cover 25 is fixedly connected to the sealing plate 26.

[0052] The bottom of the sealing plate 26 is fixedly connected to the primary cold plate 23 via a low thermal conductivity support column 4. The bottom of the sealing plate 26 is also provided with a primary cold head 32, which is located on the bottom of the sealing plate 26 near the secondary cold head 33. The top of the primary cold head 32 is connected to the sealing plate 26, and the bottom of the primary cold head 32 is connected to the primary cold plate 23.

[0053] Specifically, the support column 27 between the sealing plate 26 and the first-stage cold plate 23 is made of high-strength glass fiber material with low thermal conductivity. The vacuum cover 25 and the sealing plate 26 are fitted on the outside of the first-stage cold screen 24. The vacuum cover 25 and the sealing plate 26 are used to isolate the outside from the first-stage cold screen 24. The vacuum treatment reduces heat transfer and prevents external heat energy from being transferred to the inside of the vacuum cover 25.

[0054] Furthermore, it also includes a pre-cooling refrigerator 31, the room temperature portion of which is located on the side of the sealing plate near the first-stage cold head, and the room temperature portion of the pre-cooling refrigerator is connected to the sealing plate.

[0055] A shock-absorbing bellows is provided between the pre-cooling refrigeration unit 31 and the vacuum hood 25.

[0056] Specifically, the precooling refrigerator 31 is used for precooling. It adopts a two-stage GM type pulse tube precooling refrigerator 31. The precooling refrigerator 31 is used to provide cooling capacity. The vibration damping corrugated pipe can reduce the vibration of the precooling refrigerator 31. The cooling capacity transmitted by the precooling refrigerator 31 passes through the first-stage cold head 32, the first-stage cold plate 23, the second-stage cold head 33, the flexible connector 34, and the second-stage cold plate 22 in sequence, and is finally transmitted to the insulation and demagnetization module through the first thermal switch 4.

[0057] Furthermore, it includes a normal cooling mode and a vibration-free cooling mode, wherein the normal cooling mode includes the following steps:

[0058] The pre-cooling refrigerator 31 starts to cool, closes the first thermal switch 4 and the second thermal switch 13, and pre-cools the insulation and demagnetization module 1 through the pre-cooling module 3;

[0059] After pre-cooling to the temperature of heat sink 14, the adiabatic demagnetization module 1 operates, and the magnetothermal module 11 is magnetized while being cooled. After reaching the target magnetic field, the second thermal switch 13 is disconnected, followed by adiabatic demagnetization, isothermal demagnetization cooling, adiabatic magnetization, and then the second thermal switch 13 is closed for isothermal magnetization, entering periodic cooling. In this mode, the pre-cooling refrigerator 31 remains running, and the first thermal switch 4 remains closed, which is the normal cooling mode.

[0060] The vibration-free cooling mode includes the following steps:

[0061] The pre-cooling refrigerator 31 starts to cool, closes the first thermal switch 4 and the second thermal switch 13, and pre-cools the insulation and demagnetization module 1 through the pre-cooling module 3;

[0062] After precooling to the temperature of heat sink 14, the adiabatic demagnetization module 1 operates. The magnetothermal module 11 is magnetized and cooled at the same time. After reaching the target magnetic field, the second thermal switch 13 and the first thermal switch 4 are disconnected. At the same time, the precooling refrigerator 31 stops running. The precooling module 3 and the adiabatic demagnetization module 1 are in a heat transfer disconnected state. The magnetothermal module 11 performs adiabatic demagnetization and isothermal demagnetization refrigeration. In this mode, the precooling refrigerator 31 is always in a stopped state, and the first thermal switch 4 is always in a disconnected state, which is a vibration-free refrigeration mode.

[0063] The pre-cooling refrigerator 31 restarts to cool, closes the first thermal switch 4 and the second thermal switch 13, and the insulation demagnetization module 1 starts to operate. The magnetothermal module 11 is magnetized and cooled at the same time. After reaching the target magnetic field, the second thermal switch 13 and the first thermal switch 4 are disconnected, and the pre-cooling refrigerator 31 stops running and starts a new round of vibration-free cooling mode.

[0064] Specifically, firstly, the vacuum chamber 25 is evacuated until the pressure is below 0.1 Pa. Then, the pre-cooling refrigerator 31 is started, and the first thermal switch 4 and the second thermal switch 13 are closed. The pre-cooling module 3 pre-cools the adiabatic demagnetizing module 1. The first-stage cold head 32 is cooled to around 30 K, and the second-stage cold head 33 is cooled to around 4 K. At the same time, the adiabatic demagnetizing module is pre-cooled to around 4 K. The adiabatic demagnetizing module 1 is then in operation. The magnetothermal module 11 is magnetized and cooled at the same time. After reaching the target magnetic field, the adiabatic demagnetizing process begins.

[0065] In normal cooling mode, the pre-cooling refrigerator 31 remains running, and the first thermal switch 4 is always closed. During the adiabatic demagnetization process, when the temperature of the magnetothermal module 11 drops to the cooling temperature, the second thermal switch 13 remains open, and the isothermal demagnetization cooling process begins, with a certain load 12 applied. When the magnetic field is reduced to zero, the first cooling cycle ends, and the second thermal switch 13 remains open, entering the adiabatic magnetization process. When the magnetothermal module 11 heats up to a temperature slightly higher than that of the heat sink 14, the second thermal switch 13 is closed, and the magnetothermal module 11 isothermally magnetized, generating magnetization heat, which is released to the heat sink 14 through the second thermal switch 13. When the magnetothermal module 11 is magnetized to the maximum magnetic field, the normal periodic cooling process begins.

[0066] In the vibration-free operation mode, the precooling refrigerator 31 remains stationary, and the first thermal switch 4 remains open. When the magnetothermal module 11 is cooled and simultaneously magnetized to the target magnetic field, the second thermal switch 13 and the first thermal switch 4 are disconnected, and the precooling refrigerator 31 stops operating. The precooling module 3 and the adiabatic demagnetizing module 1 are in a heat transfer disconnected state, and the magnetothermal module 11 undergoes adiabatic demagnetization. When the temperature of the magnetothermal module 11 drops to the cooling temperature, the second thermal switch 13 remains open, and the isothermal demagnetization cooling process begins, implementing vibration-free cooling for the load 12. When the isothermal demagnetization reaches zero magnetic field, the precooling refrigerator 31 restarts for cooling, the first thermal switch 4 and the second thermal switch 13 are closed, the adiabatic demagnetizing module 1 operates, and the magnetothermal module 11 is magnetized and cooled simultaneously. After reaching the target magnetic field, the second thermal switch 13 and the first thermal switch 4 are disconnected, and the precooling refrigerator 31 stops operating, initiating a new round of vibration-free cooling mode.

[0067] In one embodiment, the type of precooling refrigerator and the cooling temperature range of the precooling refrigerator can be selected according to actual conditions. This invention is a single-stage adiabatic demagnetization system, but it can also be configured with multi-stage adiabatic demagnetization, multiple cooling temperatures, and multiple heat sink temperatures according to actual needs. The magnetocaloric material of the adiabatic demagnetization module 1 can also be selected according to actual needs. In a single-stage adiabatic demagnetization system, it can be gadolinium gallium garnet or gadolinium lithium fluoride, etc. In a multi-stage adiabatic demagnetization system, the lower temperature stage can be potassium chromium alum or iron ammonium alum, etc., all of which can be selected according to actual needs. The first thermal switch 4 and the second thermal switch 13 in this application can also be selected according to actual cooling needs, such as air gap thermal switches, superconducting thermal switches, magnetoresistive thermal switches, and mechanical thermal switches, etc. Similarly, the material types of other components of this invention can also be selected according to actual conditions and needs.

[0068] Of course, the present invention may have many other embodiments. Based on this embodiment, other embodiments obtained by those skilled in the art without any creative effort are all within the scope of protection of the present invention.

Claims

1. A vibration-free, adiabatic demagnetizing refrigeration system, characterized in that, It includes an insulation and demagnetization module, a framework module, and a precooling module, wherein: The structural module includes a secondary cold screen fitted around the outside of the thermal insulation and demagnetization module; The thermal insulation and demagnetization module includes a magnetic heating module, the bottom of which is connected to a load, and the magnetic heating module is connected to a heat sink via a second thermal switch. The magnetocaloric module is connected to the suspension structure on both the upper and lower sides. The outer edge of the suspension structure is fixed to the upper and lower end faces of the magnetic shield. The magnetocaloric module is fixed to the middle of the annular superconducting magnet through the suspension structure. The magnetocaloric module does not contact the superconducting magnet. The thermal insulation and demagnetization module includes the magnetic shield, and one side of the top of the magnetic shield is connected to the heat sink via a high thermal conductivity copper rod. The heat sink is provided with a first thermal switch on one side of its top, and the secondary cold screen is also provided with a secondary cold plate on its top. The secondary cold plate is fixedly connected to the secondary cold screen. The heat sink is connected to the secondary cold plate through the first thermal switch, and the heat sink is fixed to the secondary cold plate through a low thermal conductivity support column. The precooling module is located on top of the secondary cold tray and connected to the secondary cold tray.

2. The vibration-free adiabatic demagnetizing refrigeration system according to claim 1, characterized in that, It also includes a primary cold screen and a primary cold plate, wherein the primary cold screen is fitted over the secondary cold screen and the primary cold plate are fixedly connected.

3. The vibration-free adiabatic demagnetizing refrigeration system according to claim 2, characterized in that, The bottom of the primary cold plate is fixedly connected to the top of the secondary cold plate via a low thermal conductivity support column.

4. The vibration-free adiabatic demagnetizing refrigeration system according to claim 3, characterized in that, A secondary cold head is provided on one side of the bottom of the primary cold plate. The top side of the secondary cold head is connected to the primary cold plate. A flexible connector is provided on one side of the bottom of the secondary cold head. The bottom of the secondary cold head is fixedly connected to the secondary cold plate through the flexible connector.

5. The vibration-free adiabatic demagnetizing refrigeration system according to claim 4, characterized in that, It also includes a vacuum hood and a sealing plate, wherein the vacuum hood is fitted over the outside of the primary cold shield and the vacuum hood is fixedly connected to the sealing plate.

6. The vibration-free adiabatic demagnetizing refrigeration system according to claim 5, characterized in that, The bottom of the sealing plate is fixedly connected to the first-stage cold plate via a low thermal conductivity support column.

7. The vibration-free adiabatic demagnetizing refrigeration system according to claim 6, characterized in that, The bottom of the sealing plate is also provided with a primary cold head, which is located on the side of the bottom of the sealing plate close to the secondary cold head. The top of the primary cold head is connected to the sealing plate, and the bottom of the primary cold head is connected to the primary cold plate.

8. The vibration-free adiabatic demagnetizing refrigeration system according to claim 7, characterized in that, It also includes a pre-cooling refrigerator, the room temperature portion of which is located on the side of the sealing plate near the first-stage cold head, and the room temperature portion of the pre-cooling refrigerator is connected to the sealing plate.

9. The vibration-free adiabatic demagnetizing refrigeration system according to claim 8, characterized in that, A shock-absorbing corrugated pipe is provided between the pre-cooling refrigeration unit and the vacuum hood.

10. A refrigeration method for a vibration-free adiabatic demagnetizing refrigeration system according to any one of claims 1-9, characterized in that, It includes a normal cooling mode and a vibration-free cooling mode, wherein the normal cooling mode includes the following steps: The pre-cooling refrigeration unit starts to cool, closes the first and second thermal switches, and pre-cools the insulation and demagnetization module through the pre-cooling module; After precooling to the heat sink temperature, the adiabatic demagnetization module operates. The magnetothermal module is magnetized and cooled simultaneously. Once the target magnetic field is reached, the second thermal switch is disconnected, followed by adiabatic demagnetization, isothermal demagnetization refrigeration, adiabatic magnetization, and then the second thermal switch is closed for isothermal magnetization, entering the periodic refrigeration phase. In this mode, the precooling refrigeration unit remains running, and the first thermal switch is always closed, which is the normal refrigeration mode. The vibration-free cooling mode includes the following steps: The pre-cooling refrigeration unit starts to cool, closes the first and second thermal switches, and pre-cools the insulation and demagnetization module through the pre-cooling module; After precooling to the heat sink temperature, the adiabatic demagnetization module operates. The magnetothermal module is magnetized and cooled simultaneously. Once the target magnetic field is reached, the second thermal switch and the first thermal switch are disconnected. At the same time, the precooling refrigerator stops running. The precooling module and the adiabatic demagnetization module are in a heat transfer disconnected state. The magnetothermal module performs adiabatic demagnetization and isothermal demagnetization refrigeration. In this mode, the precooling refrigerator is always stopped and the first thermal switch is always open, which is a vibration-free refrigeration mode. The pre-cooling refrigerator restarts to begin cooling, closes the first and second thermal switches, and the insulation and demagnetization module begins operation. The magnetothermal module is magnetized and cooled simultaneously. Once the target magnetic field is reached, the second and first thermal switches are disconnected, and the pre-cooling refrigerator stops running, starting a new round of vibration-free cooling mode.

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