Mechanical thermal switch and low-temperature system

Abstract

The invention relates to the technical field of low temperature, and provides a mechanical thermal switch and a low-temperature system. The screw rod is static relative to the fixing assembly in the first direction; the movable block is provided with a threaded hole, the periphery of the screw rod is sleeved with the movable block, and the movable block is in threaded connection with the screw rod; the pair of multi-connecting-rod mechanisms is hinged to the two sides of the moving block respectively, and the multi-connecting-rod mechanisms are hinged to the fixing assembly; the clamping blocks are correspondingly hinged to the multi-connecting-rod mechanisms respectively; under the rotating action of the screw rod, the moving block moves in the first direction, and the moving block can drive the pair of clamping blocks to be opened and closed in parallel in the second direction through the multi-connecting-rod mechanism. According to the mechanical thermal switch and the low-temperature system provided by the invention, through parallel opening and closing of the clamping blocks, uniform stress on the contact surface is ensured, the clamping blocks are driven by the screw, the clamping torque is increased, and the heat conduction efficiency can also be improved.

Description

Technical Field

[0001] The present invention relates to the field of cryogenic technology, and particularly to a mechanical thermal switch and a cryogenic system. Background Art

[0002] Ultra-low temperature refrigeration technology refers to the refrigeration technology for obtaining temperatures below 1 K, which is currently mainly applied to space observation and quantum computers, etc. For space observation, at ultra-low temperatures, the thermal noise of the detection device itself can be reduced, the thermal interference of the space environment can be effectively shielded, the accuracy and sensitivity of the detector can be improved, and the effective measurement of weak signals can be achieved. For superconducting quantum computers, ultra-low temperatures can maintain the coherent characteristics of quantum computing to ensure the accuracy of quantum computing.

[0003] Currently, there are three commonly used technologies to achieve ultra-low temperatures: adsorption refrigeration, dilution refrigeration, and adiabatic demagnetization refrigeration. Compared with the first two refrigeration technologies, adiabatic demagnetization refrigeration has high thermodynamic efficiency and is easy to couple with the pre-stage. An adiabatic demagnetization refrigerator uses the magnetocaloric effect of paramagnetic substances to achieve refrigeration. A thermal switch is one of its key components, which is used to control the heat exchange between the magnetocaloric module and the radiator, and its performance is one of the key factors determining the overall efficiency of the adiabatic demagnetization refrigerator.

[0004] There are usually four commonly used thermal switches, namely superconducting thermal switches, magnetoresistive thermal switches, gas-gap thermal switches, and mechanical thermal switches. Superconducting thermal switches work based on the characteristics of superconductors, and use the significant difference in thermal conductivity between their normal state and superconducting state to control the on-off of heat flow. Their operating temperature is relatively low, and generally there will be a large switching ratio only below 0.5 K. Magnetoresistive thermal switches use the characteristic that the thermal conductivity of metal materials changes with the external magnetic field to achieve conduction and cutoff, and they are applicable to a wide temperature range, but a large magnetic field needs to be provided. Gas-gap thermal switches achieve conduction by raising the temperature of the adsorption pump to fill the closed metal cavity with 4 He or 3 He gas, and reduce the temperature of the adsorption pump, and the gas is re-adsorbed by the adsorbent particles such as activated carbon in the adsorption cavity to achieve the disconnection of the thermal switch. This type of thermal switch has a simple and compact structure, but there is an inevitable parasitic heat load and a slow response speed. Mechanical thermal switches use mechanical motion to control the contact and separation of two surfaces to achieve two states of conduction and disconnection. This type of switch is not restricted by the temperature range, is easy to operate, and there is no conduction heat leakage in the off state.

[0005] In the prior art, mechanical thermal switches usually have problems such as uneven surface force on the opening and closing surfaces and insufficient clamping force, resulting in low heat transfer efficiency. Summary of the Invention

[0006] The present invention provides a mechanical thermal switch and a cryogenic system, which are used to solve the defects of uneven force and insufficient clamping force in the prior art, resulting in low heat transfer efficiency, and to achieve uniform force on the surface of the clamping block, increase the clamping torque, and be beneficial to improving the heat transfer efficiency in the closed state.

[0007] The present invention provides a mechanical thermal switch, including: A fixed component, fixedly arranged; A screw rod, which is relatively stationary with respect to the fixed component in the first direction; A moving block, which has a threaded hole. The moving block is sleeved on the outer periphery of the screw rod, and the moving block is threadedly connected to the screw rod; A pair of multi-link mechanisms, which are respectively hinged to both sides of the moving block, and the multi-link mechanism is hinged to the fixed component; A pair of clamping blocks, which are respectively correspondingly hinged to the multi-link mechanism; Under the rotation of the screw rod, the moving block moves in the first direction, and the moving block can drive a pair of the clamping blocks to open and close in parallel through the multi-link mechanism.

[0008] According to the mechanical thermal switch provided by the present invention, the fixed component includes: A support member, on which the screw rod is embedded; A pair of cover plates, which are arranged on both sides of the support member. A pair of the cover plates and the support member enclose an accommodation space, and the moving block and the multi-link mechanism are located in the accommodation space; the second end of the screw rod is fixedly connected to the cover plate.

[0009] According to the mechanical thermal switch provided by the present invention, the multi-link mechanism includes: A first link, the first end of which is hinged to the moving block; A second link, the first end of which is hinged to the second end of the first link; A third link, the first end of which is hinged to the second end of the second link, and the second end of the third link is hinged to the cover plate; A lifting rod, one end of which is hinged to the cover plate, and the other end of the lifting rod is hinged to the clamping block.

[0010] According to the mechanical thermal switch provided by the present invention, the clamping block includes: A pair of side plates, which are oppositely arranged; A connecting plate, the two sides of which are respectively connected to the side plates; a third link and a lifting rod are hinged between the pair of side plates, and the lifting rod is closer to the opening and closing surface of the clamping block than the third link.

[0011] According to the mechanical thermal switch provided by the present invention, the fixed component further includes: The fixed block has its two side walls fixedly connected to the cover plate, and the top of the fixed block is rotatably abutted against the second end of the screw.

[0012] According to a mechanical thermal switch provided by the present invention, the clamping block is a copper block, and the fixing assembly, the screw, and the multi-link mechanism are all stainless steel parts.

[0013] The present invention also provides a cryogenic system, including: a vacuum cover plate, with the first side at room temperature and the second side being the vacuum side; A primary cold plate and a secondary cold plate, which are sequentially arranged at intervals on the vacuum side of the vacuum cover plate; The mechanical thermal switch as described above is arranged on the side of the secondary cold plate facing away from the primary cold plate; A rotating rod penetrates through the vacuum cover plate and the primary cold plate, and the rotating rod is connected to the screw of the mechanical thermal switch.

[0014] According to a cryogenic system provided by the present invention, the rotating rod is a stainless steel rotating rod, and further includes: An adapter is arranged between the rotating rod and the screw, and the heat conduction efficiency of the adapter is lower than that of the rotating rod.

[0015] According to a cryogenic system provided by the present invention, it further includes: A limit block is sleeved on the outer periphery of the rotating rod, and the limit block is arranged on the top of the primary cold plate, and the limit block is in clearance fit with the rotating rod.

[0016] According to a cryogenic system provided by the present invention, a side sealing device is arranged between the spiral rod and the vacuum cover plate.

[0017] For the mechanical thermal switch provided by the present invention, on the one hand, under the action of the screw, the moving block moves in the first direction, and the moving block can drive a pair of clamping blocks to open and close parallelly in the second direction through the multi-link mechanism, so that the force on the surface of the clamping blocks is uniform. On the other hand, using the screw to drive the clamping blocks increases the clamping torque. Through the above two aspects of settings, it is beneficial to enhance the heat conduction efficiency in the closed state.

[0018] For the cryogenic system provided by the present invention, since it includes the mechanical switch as described above, it has various advantages as described above. In addition, it can also reduce the heat leakage of the thermal switch and avoid the problem of vacuum leakage during use. Description of the Drawings

[0019] To more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0020] Figure 1 It is a schematic structural diagram of a mechanical thermal switch provided by the present invention.

[0021] Figure 2 It is a schematic structural diagram of the mechanical thermal switch provided by the present invention in the off state.

[0022] Figure 3 It is a schematic structural diagram of the mechanical thermal switch provided by the present invention in the on state.

[0023] Figure 4 It is an installation schematic diagram of the mechanical thermal switch provided by the present invention in a cryogenic system.

[0024] Figure 5 It is a schematic structural diagram of a side sealing device in the cryogenic system provided by the present invention.

[0025] Reference numerals: 1, fixed component; 2, screw; 3, moving block; 4, multi-link mechanism; 5, clamping block; 11, support plate; 12, cover plate; 13, fixed block; 41, first link; 42, second link; 43, third link; 44, lifting rod; 51, side plate; 52, connecting plate; 10, vacuum cover plate; 20, primary cold plate; 30, secondary cold plate; 40, rotating rod; 50, adapter; 60, limit block; 70, side sealing device; 80, operating handle; 71, gasket; 72, O-ring. Detailed implementation manners

[0026] To make the objectives, technical solutions and advantages of the present invention clearer, the following will clearly and completely describe the technical solutions in the present invention with reference to the drawings in the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0027] The following will describe Figures 1 - 3 the mechanical thermal switch of the present invention, which includes a fixed component 1, a screw 2, a moving block 3, a pair of multi-link mechanisms 4 and a pair of clamping blocks 5.

[0028] The fixed component 1 is fixedly arranged and serves as the basic support part of the entire device. It is firmly fixed at the target position through a specific installation method, providing a stable support for the operation of subsequent components. The screw rod 2 maintains a relatively static relationship with the fixed component 1 in the first direction, and the outer periphery of the screw rod 2 has threads. A threaded hole matching the screw rod 2 is provided on the moving block 3. The moving block 3 is sleeved on the outer periphery of the screw rod 2 and is threadedly connected to the screw rod 2. When an operator rotates the screw rod 2, due to the relative static characteristic of the screw rod 2 with respect to the fixed component 1, the screw rod 2 remains stationary in the first direction, while the moving block 3 moves up and down along the first direction under the action of screw drive. Here, the first direction is the axial direction of the screw rod 2. A pair of multi-link mechanisms 4 are respectively hinged to both sides of the moving block 3, and the multi-link mechanism 4 is hinged to the fixed component 1. The multi-point hinged manner endows good movement flexibility. A pair of clamping blocks 5 are respectively hinged to the multi-link mechanism 4, forming an overall structure that is interrelated and moves in coordination.

[0029] In the mechanical thermal switch provided by the present invention, the rotation of the screw rod 2 becomes the power source for the operation of the entire system. Under the rotation of the screw rod 2, the moving block 3 moves in the first direction. Due to its unique geometric structure, the multi-link mechanism 4 can convert the linear motion of the moving block 3 into the parallel opening and closing motion of a pair of clamping blocks 5. This parallel opening and closing method can ensure uniform force on the surface of the clamping blocks 5, avoiding local wear or a decrease in heat conduction efficiency caused by uneven force. At the same time, using a screw rod to drive the clamping blocks 5 makes full use of the characteristic that screw drive can increase the clamping torque. The larger clamping torque enables a pair of clamping blocks 5 to fit more closely in the closed state, thereby significantly improving the heat conduction rate and achieving efficient heat transfer.

[0030] In some feasible embodiments of the present invention, the fixed component 1 includes a support member 11 and a pair of cover plates 12. The screw rod 2 is embedded in the support member 11, ensuring the stability of the screw rod 2 during power transmission and enabling the moving block 3 to move precisely and smoothly in the first direction. A pair of cover plates 12 are arranged on both sides of the support member 11. The pair of cover plates 12 and the support member 11 enclose an accommodation space, and the moving block 3 and the multi-link mechanism 4 are located in the accommodation space, providing good protection and a compact layout for the moving block 3 and the multi-link mechanism 4. The second end of the screw rod 2 is fixedly connected to the cover plate 12, ensuring the high efficiency and reliability of power transmission.

[0031] More specifically, the support member 11 and the cover plate 12 are fixedly connected by pins.

[0032] In some feasible embodiments of the present invention, the multi-link mechanism 4 includes a first link 41, a second link 42, a third link 43, and a lifting rod 44. The first end of the first link 41 is hinged to the moving block 3; the first end of the second link 42 is hinged to the second end of the first link 41, and the second end of the first link 41 is inclined toward the side close to the screw rod 2. The second end of the second link 42 is inclined away from the screw rod 2 relative to the first side of the second link 42. The first end of the third link 43 is hinged to the second end of the second link 42, and the second end of the third link 43 is hinged to the cover plate 12. One end of the lifting rod 44 is hinged to the cover plate 12, and the other end of the lifting rod 44 is hinged to the clamping block 5, and the lifting rod 44 is closer to the opening and closing surface of the cover plate 12 than the third link 43.

[0033] In the above embodiments, when the moving block 2 moves along the first direction under the drive of the screw rod 2, the first link 41 can flexibly change its own angle with the hinge point as the axis, converting the linear motion of the moving block 3 into the swinging motion of the multi-link mechanism 4. The first end of the second link 42 is hinged to the second end of the first link 41. Through this hinge structure, the second link 42 and the first link 41 form a movable included angle. The included angle can be dynamically adjusted according to the swing of the first link 41 during the movement, which not only helps to further change the force transmission direction but also can buffer the impact force generated during the movement, making the movement of the entire multi-link mechanism 4 more stable. At the same time, the length of the second link 42 is greater than the length of the first link 41, and the setting of the second link 42 can extend the force transmission path, creating conditions for subsequent realization of specific motion trajectories and force amplification effects.

[0034] The first end of the third link 43 is hinged to the second end of the second link 42, and the second end is also hinged to the cover plate 12. This structure with hinges at both ends enables the third link 43 to play a key supporting and guiding role in the entire mechanism. The cover plate 12, as part of the fixed component 1, provides a stable support point for the third link 43, restricting the movement range of the third link 43 so that it can swing along a predetermined trajectory. Through cooperation with the second link 42, the third link 43 can reasonably distribute and convert the forces from the first link 41 and the second link 42, ensuring that the force can be accurately transmitted to the cover plate 12 and maintaining the structural stability of the entire multi-link mechanism during the movement, preventing shaking or deviation and ensuring the reliability of the thermal switch operation.

[0035] The hinge connection between the lifting rod 44 and the cover plate 12 provides a stable fulcrum for the lifting rod 44. Driven by the third connecting rod 43, the lifting rod 44 can accurately transmit the force to the clamping block 5, driving the clamping block 5 to open and close in parallel. The above design enables the lifting rod 44 to effectively control the movement direction and position of the clamping block 5 during the force transmission process, ensuring that the clamping block 5 remains parallel during the opening and closing process, so that the force on the surface of the clamping block is uniform. The uniform force distribution can not only improve the contact effect between the clamping block 5 and the object to be clamped, enhance the heat conduction efficiency, but also reduce the wear of the clamping block 5 and extend the service life of the thermal switch.

[0036] In some feasible embodiments of the present invention, the clamping block 5 includes a pair of side plates 51 and a connecting plate 52. The pair of side plates 51 are arranged opposite to each other; the two sides of the connecting plate 52 are respectively connected to the side plates 51, and the opposite surfaces of the two connecting plates 52 form an opening and closing surface. A third connecting rod 43 and a lifting rod 44 are hinged between the pair of side plates 51, and the lifting rod 44 is closer to the opening and closing surface of the clamping block 5 relative to the third connecting rod 43. When the lifting rod 44 drives the clamping block 5 to open and close, it can generate a larger moment with a shorter lever arm, thereby improving the opening and closing efficiency and response speed of the clamping block 5. At the same time, this layout can also ensure that the clamping block 5 is more evenly stressed during the opening and closing process, avoiding the situation where one side closes or opens first, ensuring the force consistency on the surface of the clamping block 5, and then significantly improving the uniformity and stability of heat conduction, enabling the thermal switch to achieve more accurate and efficient heat conduction control during operation.

[0037] In some feasible embodiments of the present invention, the fixing assembly 1 further includes a fixing block 13. The two side walls of the fixing block 13 are fixedly connected to the cover plate 12, which can be connected by a pin shaft, or firmly connected by welding or bonding, effectively enhancing the overall rigidity and anti-deformation ability of the fixing assembly 1. During the operation of the thermal switch, even if component misalignment or loosening occurs due to structural deformation, it provides a reliable operating environment for key internal components such as the moving block 3 and the multi-link mechanism 4, greatly improving the reliability and stability of the thermal switch operation.

[0038] In addition, the top of the fixed block 13 is rotatably connected to the second end of the screw 2, so that when the screw 2 rotates, the fixed block 13 can be used as a stable support point, which effectively reduces the radial shaking and axial movement of the screw 2 during the rotation process, and ensures that the screw 2 will not be displaced in the longitudinal direction during rotation. Compared with the structure without the fixed block 13, the rotation accuracy of the screw 2 is significantly improved, just like adding a precise "locator" to the rotation of the screw 2. The high-precision rotation not only ensures that the moving block 3 can move up and down accurately and smoothly along the first direction, but also makes the movement of the multi-link mechanism 4 and the clamping block 5 more precise and controllable, ensuring that the clamping block 5 can achieve high-precision parallel movement during the opening and closing process, thereby improving the contact accuracy and fitting effect between the clamping block 5 and the clamped object, laying a solid foundation for improving the heat conduction efficiency.

[0039] In some feasible embodiments of the present invention, the clamp block 5 is a copper block, and the surface thereof may be gold plated. The fixing assembly 1, the screw rod 2, and the multi-link mechanism 4 are all made of stainless steel, and the purpose of the arrangement is to reduce the heat leakage of the thermal switch.

[0040] Therefore, in the mechanical thermal switch provided by the first embodiment of the present invention, the clamping blocks 5 open and close in parallel to ensure that the contact surface is subjected to uniform force. The clamping blocks 5 are driven by the screw 2 to increase the clamping torque and improve the heat conduction efficiency.

[0041] The working process of the mechanical thermal switch provided by the present invention is to rotate the screw rod 2 clockwise, and the moving block 3 translates downward, driving the first connecting rod 41, the second connecting rod 42, and the third connecting rod 43 to move, and driving the lifting rod 44 to drive the clamping block 5 to close in parallel until it is clamped. Among them, the end of the screw rod 2 facing away from the force-applying end is stuck in the fixed block 13 to ensure that the screw rod 2 will not be displaced in the longitudinal direction during rotation. Similarly, when disconnecting the thermal switch, it only needs to rotate the operating handle 80 counterclockwise for the same number of turns to achieve complete disconnection.

[0042] like Figure 4 As shown, the second aspect of the present invention is to provide a low-temperature system, including a vacuum cover plate 10, a primary cold plate 20, a secondary cold plate 30, a rotating rod 40 and a mechanical thermal switch as described in any of the above embodiments, the first side of the vacuum cover plate 10 is room temperature, and the second side is a vacuum side; the primary cold plate 20 and the secondary cold plate 30 are arranged in sequence on the vacuum side of the vacuum cover plate 10; the mechanical thermal switch is arranged on the side of the secondary cold plate 30 facing away from the primary cold plate 20; the rotating rod 40 passes through the vacuum cover plate 10 and the primary cold plate 20, and the rotating rod 40 is connected to the screw 2 of the mechanical thermal switch.

[0043] The mechanical thermal switch is installed. A plate-shaped copper bar is extended from each of the salt pill of the adiabatic demagnetization refrigerator and the heat sink of the salt pill as a heat conduction belt. The two heat conduction belts are longitudinally placed in the middle of the clamping block 5 of the thermal switch. The operating handle 80 is rotated clockwise, thereby driving the screw rod 2 to rotate clockwise. The moving block 3 moves downward, driving the first connecting rod 41, the second connecting rod 42, and the third connecting rod 43 to move, and finally driving the clamping block 5 to close in parallel until it is clamped. When disconnecting the thermal switch, just rotate the operating handle counterclockwise by the same number of turns to achieve complete disconnection.

[0044] In some feasible embodiments of the present invention, the rotating rod 40 is a stainless steel rotating rod, and further includes a swivel joint 50, which is arranged between the rotating rod 40 and the screw rod 2, and the heat conduction efficiency of the swivel joint 50 is lower than that of the rotating rod 40, reducing the heat leakage of the thermal switch. Among them, the rotating rod 40 can adopt a thin-walled stainless steel pipe, and the wall thickness of the thin-walled stainless steel pipe is usually 0.1-0.2 mm. The swivel joint 50 can be made of fiberglass or polytetrafluoroethylene, etc.

[0045] In some feasible embodiments of the present invention, it further includes a limit block 60, which is sleeved on the outer periphery of the rotating rod 40, and the limit block 60 is arranged on the top of the first-stage cold plate 20, and the limit block 60 is in clearance fit with the rotating rod 40. The limit block 60 usually adopts a copper block and is precooled.

[0046] As Figure 5 shown, in some feasible embodiments of the present invention, a side sealing device 70 is arranged between the rotating rod 40 and the vacuum cover plate 10 to ensure the vacuum degree of the cryogenic system. The side sealing device 70 can include a gasket 71 and a plurality of O-ring seals 72.

[0047] Therefore, for the cryogenic system provided by the second aspect embodiment of the present invention, since it includes the mechanical thermal switch of the above embodiment, the clamping block 5 opens and closes in parallel, which can ensure uniform force on the contact surface. The clamping block 5 is driven by the screw rod 2, increasing the clamping torque and improving the heat conduction efficiency. The screw rod 2 and the rotating rod 40 are connected by a material with relatively low thermal conductivity and high strength, reducing the heat leakage of the thermal switch. The rotating rod 40 adopts a thin-walled stainless steel pipe, reducing the heat leakage of the thermal switch; at the same time, a side sealing device 70 is adopted between the rotating rod 40 and the vacuum cover plate 10 to ensure the vacuum degree of the cryogenic system when using the thermal switch.

[0048] In the description of the embodiments of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific situations.

[0049] In the description of this specification, the description referring to terms such as "one embodiment", "some embodiments", "mode", "specific mode", or "some modes" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or mode are included in at least one embodiment or mode of the embodiments of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or mode. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or modes. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or modes described in this specification and the features of different embodiments or modes.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A mechanical thermal switch, characterized in that, Comprising: A fixed component (1), fixedly arranged; A screw rod (2), relatively stationary with respect to the fixed component (1) in a first direction; A moving block (3), having a threaded hole, the moving block (3) is sleeved on the outer periphery of the screw rod, and the moving block (3) is threadedly connected to the screw rod (2); A pair of multi-link mechanisms (4), respectively hinged to both sides of the moving block (3), and the multi-link mechanism (4) is hinged to the fixed component (1); A pair of clamping blocks (5), respectively correspondingly hinged to the multi-link mechanism (4); Under the rotational action of the screw rod (2), the moving block (3) moves in the first direction, and the moving block (3) can drive a pair of the clamping blocks (5) to open and close in parallel through the multi-link mechanism (4).

2. The mechanical thermal switch according to claim 1, wherein, The fixed component (1) comprises: A support member (11), on which the screw rod (2) is embedded; A pair of cover plates (12), arranged on both sides of the support member (11), a pair of the cover plates (12) and the support member (11) enclose an accommodation space, and the moving block (3) and the multi-link mechanism (4) are located in the accommodation space; the second end of the screw rod (2) is fixedly connected to the cover plate (12).

3. The mechanical thermal switch according to claim 2, characterized in that The multi-link mechanism (4) comprises: A first link (41), the first end of which is hinged to the moving block (3); A second link (42), the first end of which is hinged to the second end of the first link (41); A third link (43), the first end of which is hinged to the second end of the second link (42), and the second end of the third link (43) is hinged to the cover plate (12); A lifting rod (44), one end of which is hinged to the cover plate (12), and the other end of the lifting rod (44) is hinged to the clamping block (5).

4. The mechanical thermal switch according to claim 3, characterized in that, The clamping block (5) comprises: A pair of side plates (51), oppositely arranged; A connecting plate (52), connected to the side plates (51) on both sides respectively; between the pair of side plates (51), the third link (43) and the lifting rod (44) are hinged, and the lifting rod (44) is closer to the opening and closing surface of the clamping block (5) relative to the third link (43).

5. The mechanical thermal switch according to claim 2, wherein The fixed component (1) further comprises: A fixed block (13), the two side walls of which are fixedly connected to the cover plate (12), and the top of the fixed block (13) is rotatably abutted against the second end of the screw rod (2).

6. The mechanical thermal switch according to any one of claims 1-5, characterized in that, The clamping block (5) is a copper block, and the fixed component (1), the screw rod (2), and the multi-link mechanism (4) are all stainless steel parts.

7. A cryogenic system, characterized in that, Comprising: A vacuum cover plate (10), the first side is at room temperature, and the second side is the vacuum side; A primary cold plate (20) and a secondary cold plate (30), sequentially arranged at intervals on the vacuum side of the vacuum cover plate (10); The mechanical thermal switch according to any one of claims 1-6, arranged on the side of the secondary cold plate (30) facing away from the primary cold plate (20); A rotating rod (40), passing through the vacuum cover plate (10) and the primary cold plate (20), and the rotating rod (40) is connected to the screw rod (2) of the mechanical thermal switch.

8. The cryogenic system according to claim 7, wherein The rotating rod is a stainless steel rotating rod, and further comprises: An adapter (50) is provided between the rotating rod (40) and the screw rod (2), and the heat conduction efficiency of the adapter (50) is lower than that of the rotating rod (40).

9. The cryogenic system according to claim 7, wherein It further includes: A limit block (60) is sleeved on the outer periphery of the rotating rod (40), and the limit block (60) is arranged on the top of the primary cold plate (20). The limit block (60) is in clearance fit with the rotating rod (40).

10. The cryogenic system according to claim 7, characterized in that, A side sealing device (70) is provided between the rotating rod (40) and the vacuum cover plate (10).

Images