Cryogenic sample holder

Abstract

The application provides a low-temperature sample support, which comprises a refrigeration device, a sample fixing groove and a motion mechanism, the motion mechanism comprises at least two vacuum motors, at least two transmission assemblies and at least two motion assemblies, the sample fixing groove is fixed to the motion mechanism, the sample fixing groove is connected with the refrigeration device through a heat transfer assembly, the vacuum motor drives the corresponding motion assembly to move through the corresponding transmission assembly, so that the sample fixing groove and the sample move relative to the vacuum cavity in multiple dimensions, and no relative motion is generated between the at least two vacuum motors, the influence of the gravity moment of the vacuum motor on the sample motion is eliminated by eliminating the mutual motion between the at least two vacuum motors. The heat conduction channel between the motion mechanism, the sample fixing groove and the room temperature environment is only composed of low-heat-conducting wires, so that the heat conduction between the low-temperature component and the external environment can be effectively reduced, and a lower sample temperature can be achieved.

Description

Technical Field

[0001] This invention relates to the field of cryogenic refrigeration, and in particular to a cryogenic sample holder. Background Technology

[0002] In low-temperature experiments and applications, low-temperature sample holders need to enable multi-degree-of-freedom motion (such as three-dimensional rotation and three-dimensional translation) of the sample while cooling it in order to achieve precise sample positioning.

[0003] There are currently two implementation schemes for vacuum cryogenic sample holders.

[0004] One approach involves connecting a mechanical transmission device to a motor located outside the vacuum chamber at room temperature to enable multi-degree-of-freedom motion of the sample. However, this approach, due to the mechanical transmission device, creates a significant heat transfer channel between the low-temperature components inside the vacuum chamber and the high-temperature external environment, making it difficult to achieve lower sample temperatures.

[0005] The second approach involves using a vacuum motor located on the cryogenic side to drive the sample and achieve multi-degree-of-freedom motion. This approach employs a nested structure, where subsequent degrees of freedom are superimposed on those of preceding stages, resulting in a significant torque load on the preceding drive motor. Furthermore, the motor's output torque decreases severely at low temperatures, and the flexible thermal conductive components exhibit cryogenic hardening. With prolonged use, these components gradually harden, increasing resistance to the sample's multi-degree-of-freedom motion and further increasing the torque requirement for the drive motor. Therefore, reducing the thermal conductivity of the heat transfer channels between the cryogenic components inside the vacuum chamber and the external high-temperature environment to achieve lower sample temperatures, and minimizing the torque requirements of the drive motor to ensure the long-term reliability of the cryogenic sample holder, are pressing issues that need to be addressed. Summary of the Invention

[0006] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a low-temperature sample holder to solve the problems of the large thermal conductivity heat transfer channel between the internal low-temperature components and the external room temperature environment, making it difficult to achieve lower sample temperatures, and the large demand on the output torque of the low-temperature side vacuum motor.

[0007] To achieve the above and other related objectives, the present invention provides a low-temperature sample holder, housed within a vacuum chamber, the low-temperature sample holder comprising: a cooling device, a sample fixing slot, and a motion mechanism; wherein,

[0008] The refrigeration device provides a low-temperature cold source;

[0009] The motion mechanism includes at least two vacuum motors, at least two transmission components, and at least two motion components. The sample fixing slot is fixed to the motion components. The sample fixing slot is connected to the refrigeration device through a heat transfer component. The vacuum motors drive the motion components to move through the transmission components, so as to realize multi-dimensional movement of the sample fixing slot and the sample fixed therein relative to the vacuum chamber. The heat conduction channel between the motion mechanism and the sample fixing slot and the room temperature environment is only composed of low thermal conductivity wires.

[0010] When the vacuum motor drives the motion component, there is no relative motion between at least two of the vacuum motors.

[0011] Optionally, the motion component is provided with a counterweight to adjust the overall center of gravity of the motion component and all components fixed to the motion component to the axis of rotation of the motion component.

[0012] Optionally, the vacuum motor is a vacuum motor with a position encoder. The vacuum motor is connected to a motor controller located outside the vacuum chamber via the low thermal conductivity wire to control the movement of the motion component. The low thermal conductivity wire includes one or more combinations of constantan wire, phosphorus tin copper wire, manganese copper wire, and German silver wire.

[0013] Optionally, the vacuum motor includes one or more combinations of ceramic vacuum motors, electromagnetic vacuum motors, electrostatic vacuum motors, magnetostrictive vacuum motors, and shape memory alloy vacuum motors.

[0014] Optionally, the sample is inserted into the sample fixing groove and pressed against the sample fixing groove by a spring plate or threaded fastener.

[0015] Optionally, the transmission assembly includes one or more combinations of transmission rods, gears, racks, worm gears, lead screws, timing belts, flexible chains, flexible shafts, and universal joints.

[0016] Optionally,

[0017] The heat transfer component is a flexible heat transfer component, and its two ends are respectively connected to the sample fixing groove and the cooling device.

[0018] Alternatively, the heat transfer component may include a flexible heat transfer component and a rigid heat transfer component, wherein one end of the rigid heat transfer component is connected to the refrigeration device, the other end is connected to one end of the flexible heat transfer component, and the other end of the flexible heat transfer component is connected to the sample fixing groove.

[0019] Furthermore, the rigid heat transfer component is made of a thermally conductive material, and the flexible heat transfer component is made of a filament or a foil of a thermally conductive material.

[0020] Optionally, the transmission component is made of a thermally conductive material, and the motion component is made of a thermally conductive material.

[0021] Optionally, it also includes a heat shield; the cooling device includes a primary cold end with a higher temperature and a secondary cold end with a lower temperature, the motion mechanism and the sample fixing groove are fixed to the secondary cold end, one end of the heat transfer component is connected to the secondary cold end and the other end is connected to the sample fixing groove, the end of the heat shield is fixed to the primary cold end, the heat transfer component, the secondary cold end and all components fixed to the secondary cold end are housed in the heat shield, wherein the higher temperature is lower than room temperature, the lower temperature is lower than the higher temperature, and the material of the heat shield is a thermally conductive material.

[0022] Furthermore, the thermally conductive material includes one or more combinations of oxygen-free copper, pure silver, pure aluminum, carbon-based materials, and high thermal conductivity composite materials, and the thermally conductive material undergoes a low surface emissivity treatment.

[0023] Furthermore, the surface low emissivity treatment includes one or more combinations of surface low emissivity material coating, surface polishing treatment, and surface micro / nano structures.

[0024] Furthermore, the surface low emissivity material coating is a surface gold coating.

[0025] Optionally, an insulating high thermal conductivity material is provided at the connection between the heat transfer component and the refrigeration device. The insulating high thermal conductivity material includes one or more combinations of insulating carbon-based materials, high thermal conductivity ceramics, high thermal conductivity insulating crystals, and high thermal conductivity insulating composite materials.

[0026] Furthermore, the high thermal conductivity insulating crystal includes one or more combinations of Al2O3 crystal and TiO2 crystal.

[0027] Optionally, the connection points of each component in the low-temperature sample holder are provided with a highly ductile thermally conductive material, which includes one or more combinations of indium, silver, gold, carbon-based flexible highly thermally conductive materials and flexible highly thermally conductive composite materials.

[0028] Optionally, the refrigeration device includes one or more combinations of GM refrigerators, Stirling refrigerators, liquid helium refrigerators, dilution refrigerators, pulse tube refrigerators, magnetic refrigerators, adsorption refrigerators, thermoelectric refrigerators, and liquid helium cold traps.

[0029] Optionally, it also includes a thermometer housed within the vacuum chamber and connected to a temperature controller located outside the vacuum chamber via the low thermal conductivity wire.

[0030] Furthermore, the thermometer includes one or more combinations of resistance thermometers, diode thermometers, thermocouple thermometers, and magnetic susceptibility thermometers.

[0031] Optionally, the transmission assembly and the motion assembly have a hollow structure or a reinforcing rib structure.

[0032] Optionally,

[0033] When the vacuum motor drives the motion component to rotate through the transmission assembly, the motion component is spatially limited by the vacuum bearing.

[0034] When the vacuum motor drives the motion component to perform translational motion through the transmission assembly, the motion component is spatially limited by the linear vacuum bearing and guide rail.

[0035] Furthermore, the vacuum bearing includes one or more combinations of ceramic vacuum bearings, polymer vacuum bearings, metal vacuum bearings, and magnetic levitation vacuum bearings.

[0036] Optionally, the multidimensional motion includes one or more combinations of multidimensional rotational motion and multidimensional translational motion.

[0037] As described above, the cryogenic sample holder of the present invention has the following beneficial effects: by eliminating the relative motion between at least two vacuum motors to eliminate the influence of the gravitational torque of the vacuum motors on sample movement, the torque requirement of the vacuum motors can be significantly reduced. The heat conduction channel between the motion mechanism and the sample fixing slot and the room temperature environment is composed only of low thermal conductivity wires, which can effectively reduce the heat conduction between the cryogenic components and the external room temperature environment, achieving a lower sample temperature. Compared with the prior art, the present invention reduces the requirement for motor drive torque and increases the long-term operational reliability of the cryogenic sample holder. Attached Figure Description

[0038] Figure 1 The diagram shown is a structural schematic of the low-temperature sample holder according to Embodiment 1 of the present invention.

[0039] Figure 2 The diagram shown is a structural schematic of the low-temperature sample holder according to Embodiment 2 of the present invention.

[0040] Component designation explanation

[0041] 1. Vacuum cavity

[0042] 2. Three-dimensional translation device

[0043] 3 Refrigeration unit

[0044] 4. First-level cold end

[0045] 5 Flexible thermal conductive components

[0046] 6 Secondary cold end

[0047] 7. Heat shield

[0048] 8 First electric rotary drive motor

[0049] 9 Second electric rotary drive motor

[0050] 10 Third electric rotary drive motor

[0051] 11 First Rotary Transmission Assembly

[0052] 12 Second Rotary Transmission Component

[0053] 13 First Rotating Component

[0054] 14 Second Rotating Component

[0055] 15 Third Rotating Component

[0056] 16 Orthogonal Rotary Transmission Components

[0057] 17 Orthogonal Rotary Transmission Component Two

[0058] 18, 30 Sample fixing slots

[0059] 20 substrate

[0060] 211 First Linear Vacuum Bearing

[0061] 212 Second linear vacuum bearing

[0062] 213 Third Linear Vacuum Bearing

[0063] 22 First translation component

[0064] 23 Second translation component

[0065] 24 First electric linear drive motor

[0066] 25 Second electric linear drive motor

[0067] 26 First linear transmission assembly

[0068] 27 Second linear transmission assembly

[0069] 28 Orthogonal translational transmission assembly one

[0070] 29 Orthogonal translational transmission assembly two Detailed Implementation

[0071] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0072] Example 1

[0073] Please see Figure 1 It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0074] This embodiment provides a low-temperature sample holder, housed within a vacuum chamber 1. The low-temperature sample holder includes: a cooling device 3, a sample fixing slot 18, and a motion mechanism; wherein...

[0075] The refrigeration device 3 provides a low-temperature cold source;

[0076] The motion mechanism includes at least two vacuum motors, at least two transmission components, and at least two motion components. The sample fixing slot 18 is fixed to the motion mechanism. The sample fixing slot 18 is connected to the refrigeration device 3 through a heat transfer component. The vacuum motors drive the motion components to move through the transmission components, so as to realize multi-dimensional movement of the sample fixing slot 18 and the sample fixed therein relative to the vacuum chamber. The heat conduction channel between the motion mechanism and the sample fixing slot and the room temperature environment is only composed of low thermal conductivity wires.

[0077] When the vacuum motor drives the motion component, there is no relative motion between at least two of the vacuum motors.

[0078] This embodiment of the cryogenic sample holder eliminates the influence of the gravitational torque of the vacuum motors on sample movement by eliminating the relative motion between at least two vacuum motors, thus significantly reducing the torque requirements of the vacuum motors. The heat conduction channel between the motion mechanism and the sample fixing slot and the room temperature environment is composed only of low thermal conductivity wires, effectively reducing heat conduction between the cryogenic components and the external room temperature environment, achieving even lower sample temperatures. Compared with existing technologies, this invention reduces the demand for motor drive torque and increases the long-term operational reliability of the cryogenic sample holder.

[0079] As an example, such as Figure 1As shown, the low-temperature sample holder also includes a heat shield 7, the cooling device 3 includes a primary cold end 4 with a higher temperature and a secondary cold end 6 with a lower temperature, the motion mechanism and the sample fixing groove 18 are fixed to the secondary cold end 6, one end of the heat transfer component is connected to the secondary cold end 6 and the other end is connected to the sample fixing groove 18, the end of the heat shield 7 is fixed to the primary cold end 4, and the heat transfer component (see reference...) Figure 1 The flexible heat transfer component 5, the secondary cold end 6, and all components fixed to the secondary cold end 6 are housed within the heat shield 7. The higher temperature is below room temperature, and the lower temperature is below the higher temperature. The heat shield 7 is made of a thermally conductive material, and the moving components are also made of a thermally conductive material, preferably a high thermal conductivity material with a higher thermal conductivity than ordinary materials. The thermally conductive material includes one or more combinations of oxygen-free copper, pure silver, pure aluminum, carbon-based materials, and high thermal conductivity composite materials. The thermally conductive material undergoes a low emissivity surface treatment, which includes one or more combinations of a low emissivity material coating, surface polishing, and surface micro / nano structures. The low emissivity material coating is preferably a gold coating, as gold plating reduces emissivity, thereby reducing the heat load based on thermal radiation. Oxygen-free copper and other materials have non-magnetic properties and good thermal conductivity, which helps to obtain lower sample temperatures.

[0080] As an example, the multidimensional motion includes one or more combinations of multidimensional rotational motion and multidimensional translational motion.

[0081] As a specific example, when the multidimensional motion is a three-dimensional rotational motion, such as Figure 1 As shown, a three-dimensional translation device 2 is provided on the vacuum chamber 1. The low-temperature sample holder cooperates with the three-dimensional translation device 2 to realize the three-dimensional rotation and three-dimensional translation of the sample fixing slot 18 and the sample relative to the vacuum chamber 1. The structure of the low-temperature sample holder is described as follows:

[0082] The refrigeration device 3 is fixed on the three-dimensional translation device 2, which is used to realize the three-dimensional translation of the refrigeration device 3 and all components fixed on the refrigeration device 3 relative to the vacuum cavity 1.

[0083] The refrigeration device 2 includes a primary cold end 4 with a higher temperature and a secondary cold end 6 with a lower temperature. The end of the heat shield 7 is fixed to the primary cold end 4. One end of the heat transfer component is connected to the secondary cold end 6, and the other end is connected to the sample fixing groove 18. The heat transfer component, the secondary cold end 6, and all components fixed to the secondary cold end 6 are housed within the heat shield 7. The higher temperature is lower than room temperature, and the lower temperature is lower than the higher temperature. This temperature comparison is actually a temperature comparison between the primary cold end 4 and the secondary cold end 6.

[0084] At least two of the vacuum motors include a first electric rotary drive motor 8, a second electric rotary drive motor 9, and a third electric rotary drive motor 10; at least two of the transmission components include a first rotary transmission component 11, a second rotary transmission component 12, an orthogonal rotary transmission component 16, and an orthogonal rotary transmission component 2 17; at least two of the motion components include a first rotary component 13, a second rotary component 14, and a third rotary component 15.

[0085] The first electric rotary drive motor 10 is fixed to the secondary cold end 6; the first rotary transmission assembly 11 and the first rotary assembly 13 are both fixed to the secondary cold end 6 by vacuum bearings; the first electric rotary drive motor 10 drives the first rotary assembly 13 and all components fixed to the first rotary assembly 13 to achieve rotational movement around the rotation axis of the first rotary assembly 13 through the first rotary transmission assembly 11.

[0086] The second electric rotary drive motor 9 is fixed to the first rotary assembly 13; the second rotary transmission assembly 12 and the second rotary assembly 14 are both fixed to the first rotary assembly 13 by vacuum bearings. The second electric rotary drive motor 9 drives the second rotary assembly 14 and all components fixed to the second rotary assembly 14 to achieve rotational movement relative to the first rotary assembly 13 around the rotation axis of the second rotary assembly 14 through the second rotary transmission assembly 12.

[0087] The third electric rotary drive motor 10 is fixed to the first rotary assembly 13. The first orthogonal rotary transmission assembly 16 is fixed to the second rotary assembly 14 via a vacuum bearing. The rotation axis of the first orthogonal rotary transmission assembly 16 is coaxial with the rotation axis of the second rotary assembly 14. The first orthogonal rotary transmission assembly 16 can achieve rotational movement relative to the second rotary assembly 14. The third rotary assembly 15 is fixed to the second rotary assembly 14 via a vacuum bearing. The second orthogonal rotary transmission assembly 17 is fixed to the third rotary assembly 15. The third electric rotary drive motor 10 drives the second orthogonal rotary transmission assembly 17 via the first orthogonal rotary transmission assembly 16, thereby driving the third rotary assembly 15 and all components fixed to the third rotary assembly 15 to achieve rotational movement relative to the second rotary assembly 14 around the rotation axis of the third rotary assembly 15.

[0088] The sample fixing groove 18 is fixed to the third rotating component 15.

[0089] Based on the above structural description, when the first electric rotary drive motor 8 drives the first rotary assembly 13 and all components fixed on the first rotary assembly 13 to rotate, the sample fixing groove 18 can achieve independent rotational movement around the rotation axis of the first rotary assembly 13.

[0090] When the second electric rotary drive motor 9 drives the second rotary assembly 14 and all components fixed thereon to rotate, if the third electric rotary drive motor 10 remains stationary, the sample fixing groove 18 will rotate around the rotation axis of the second rotary assembly 14, and simultaneously rotate around the rotation axis of the third rotary assembly 15. This is explained in detail below: Since the third rotary assembly 15 is fixed to the second rotary assembly 14 via a vacuum bearing, when the second rotary assembly 14 rotates around its rotation axis, the third rotary assembly 15 and the second orthogonal rotary transmission assembly 17 fixed thereon will simultaneously rotate around the rotation axis of the second rotary assembly 14. The first orthogonal rotary transmission assembly 16 is fixed to the second rotary assembly 14 via a vacuum bearing and engages with the third electric rotary drive motor 10. Therefore, when the third electric rotary drive motor 10 remains stationary, the first orthogonal rotary transmission assembly 16 will also necessarily remain stationary. Since the orthogonal rotary transmission component 16 is rotationally symmetrical about the rotation axis of the second rotary component 14, when the third rotary component 15 and the orthogonal rotary transmission component 17 rotate about the rotation axis of the second rotary component 14, the orthogonal rotary transmission component 17 and the orthogonal rotary transmission component 16 will move relative to each other and maintain an engaging relationship.

[0091] To achieve independent rotation of the sample fixing groove 18 around the rotation axis of the second rotating component 14, the second electric rotary drive motor 9 and the third electric rotary drive motor 10 must be driven simultaneously to create a linkage between the second rotating component 14 and the third rotating component 15 with a certain motion relationship, so as to counteract the aforementioned accompanying motion.

[0092] When the third electric rotary drive motor 10 drives the third rotary assembly 15 and all components fixed thereon, the sample fixing groove 18 can achieve independent rotational movement around the rotation axis of the third rotary assembly 15.

[0093] As can be seen from the above structural description, the second electric rotary drive motor 9 and the third electric rotary drive motor 10 in this embodiment are both fixed on the first rotating component 13. Therefore, when the vacuum motor drives the motion component to move through the transmission component, there is no relative movement between the second electric rotary drive motor 9 and the third electric rotary drive motor 10, and the sample can achieve six degrees of freedom of movement, including three-dimensional translation and three-dimensional rotation, relative to the vacuum cavity 1.

[0094] In other embodiments, when the vacuum motor drives the motion component to move through the transmission component, at least two other vacuum motors may not generate relative motion. For example, the first electric rotary drive motor 8 and the second electric rotary drive motor 9 may not generate relative motion, the third electric rotary drive motor 10 and the second electric rotary drive motor 9 may not generate relative motion, the third electric rotary drive motor 10 and the first electric rotary drive motor 8 may not generate relative motion, or none of the first electric rotary drive motor 8, the second electric rotary drive motor 9, and the third electric rotary drive motor 10 may generate relative motion. In the above different embodiments, the connection structure of each component may also be changed accordingly, or even become more complex, in order to realize the multi-dimensional motion of the sample relative to the vacuum cavity 1. The specific structure and implementation method will not be described in detail here.

[0095] As a preferred example, the motion component is provided with a counterweight to adjust the overall center of gravity of the motion component and all components fixed to it to the axis of rotation of the motion component, thereby reducing the torque required for rotation. Specifically, the counterweight is installed on the first rotating component 8, the second rotating component 9, and the third rotating component 10, which can adjust the overall center of gravity to the intersection of the three rotating axes. Theoretically, by adding a counterweight to the motion component, the overall center of gravity of the motion component can be adjusted to the corresponding axis of rotation, thereby reducing the output torque requirement of the vacuum motor. However, due to the space limitations inside the vacuum chamber 1 and the heat shield 7, it is impossible to completely adjust the center of gravity to the axis of rotation within the limited space, and there is still a certain requirement for the output torque of the vacuum motor. Therefore, by eliminating the relative motion between at least two vacuum motors, the load source of motor gravity is reduced, the requirement for the output torque of the vacuum motor is significantly reduced, and the problem of insufficient output torque of the vacuum motor is effectively solved.

[0096] As an example, the vacuum motor is a vacuum motor with a position encoder, and can exemplarily include one or more combinations of ceramic vacuum motors, electromagnetic vacuum motors, electrostatic vacuum motors, magnetostrictive vacuum motors, and shape memory alloy vacuum motors. The vacuum motor is connected to a motor controller located outside the vacuum cavity 1 via the low thermal conductivity wire to control the movement of the motion component. The low thermal conductivity wire includes one or more combinations of constantan wire, phosphorus tin copper wire, manganese copper wire, and German silver wire. Preferably, in this embodiment, the low thermal conductivity wire is constantan wire. Therefore, the heat conduction between the low-temperature component inside the heat shield and the external room temperature environment only includes a heat conduction channel composed of slender constantan wire. Since the slender constantan wire has a low thermal conductivity to electrical conductivity ratio, this heat conduction channel can have extremely low thermal conductivity, thus effectively reducing the thermal conductivity of the heat transfer channel between the low-temperature component of the low-temperature sample holder and the external room temperature environment, thereby achieving a lower sample temperature.

[0097] Specifically, the sample fixing groove 18 is exemplarily provided with a slot, into which the sample is inserted and pressed against the sample fixing groove 18 by a spring sheet or threaded fastener, so as to achieve good thermal conduction between the sample and the sample fixing groove 18.

[0098] As an example, the transmission assembly includes one or more combinations of transmission rods, gears, racks, worm gears, lead screws, timing belts, flexible chains, flexible shafts, and universal joints. Any combination can be selected as needed, and no excessive restrictions are imposed here.

[0099] The sample fixing slot 18 is connected to the cooling device 3 through the heat transfer component, specifically, as shown in the example. Figure 1As shown, in this embodiment, the heat transfer component is a flexible heat transfer component 5, with both ends of the flexible heat transfer component 5 connected to the sample fixing groove 18 and the cooling device 3, respectively. Alternatively, in other embodiments, the heat transfer component may also include a flexible heat transfer component and a rigid heat transfer component (not shown), wherein one end of the rigid heat transfer component is connected to the cooling device, and the other end is connected to one end of the flexible heat transfer component, and the other end of the flexible heat transfer component is connected to the sample fixing groove 18. The length of the rigid heat transfer component can be flexibly adjusted to meet the customized requirements of different distances between the sample and the cooling device. For example, when the actual required distance between the sample and the cooling device is large, the length of the rigid heat transfer component can be increased to facilitate the setting of components connected to the cooling device.

[0100] As a further example, the rigid heat transfer component is made of a thermally conductive material, and the flexible heat transfer component is made of a thermally conductive material wire or a thermally conductive material foil. The thermally conductive material is preferably a high thermal conductivity material with a higher thermal conductivity than ordinary materials. The thermally conductive material includes one or more combinations of oxygen-free copper, pure silver, pure aluminum, carbon-based materials, and high thermal conductivity composite materials. The thermally conductive material undergoes a low surface emissivity treatment, which may include one or more combinations of a low surface emissivity material plating, surface polishing, and surface micro / nano structures. The low surface emissivity material plating is preferably a gold plating. In this embodiment, the flexible heat transfer component 5 is an oxygen-free copper braid made of oxygen-free copper wire and plated with gold. The gold plating can reduce emissivity, thereby reducing the heat load based on thermal radiation. Copper has the characteristics of being non-magnetic and having good thermal conductivity, which helps to obtain a lower sample temperature.

[0101] As a preferred example, an insulating high thermal conductivity material is provided at the connection between the heat transfer component and the cooling device 3. The insulating high thermal conductivity material includes one or more combinations of insulating carbon-based materials, high thermal conductivity ceramics, high thermal conductivity insulating crystals, and high thermal conductivity insulating composite materials. The high thermal conductivity insulating crystals include one or more combinations of Al2O3 crystals and TiO2 crystals, which helps to obtain a lower sample temperature.

[0102] As a preferred example, the connection points of each component in the low-temperature sample holder are provided with a highly ductile thermally conductive material. The highly ductile thermally conductive material includes one or more combinations of indium, silver, gold, carbon-based flexible highly thermally conductive materials and flexible highly thermally conductive composite materials, in order to achieve good thermal contact between the components.

[0103] As an example, the refrigeration device includes one or more combinations of GM refrigerators, Stirling refrigerators, liquid helium refrigerators, dilution refrigerators, pulse tube refrigerators, magnetic refrigerators, adsorption refrigerators, thermoelectric refrigerators, and liquid helium cold traps, which can be selected as needed, without excessive limitations.

[0104] As an example, the low-temperature sample holder also includes a thermometer (not shown in the figure) for measuring the temperature of the sample and the low-temperature components inside the thermal shield 7. The thermometer can be a combination of a resistance thermometer, a diode thermometer, a thermocouple thermometer, and a magnetic susceptibility thermometer. The thermometer is housed inside the vacuum chamber 1 and is connected to a temperature controller located outside the vacuum chamber 1 via a low thermal conductivity wire. The low thermal conductivity wire includes one or more combinations of constantan wire, phosphorus tin copper wire, manganese copper wire, and German silver wire. The type of thermometer and the type of low thermal conductivity wire can be selected according to actual needs, and no excessive restrictions are imposed here.

[0105] As an example, the transmission component and the motion component may have a hollow structure or a reinforcing rib structure. While ensuring the necessary functions, the use of materials is reduced as much as possible by optimizing the structural design, so that the total weight of the transmission component and the motion component is smaller than the weight of the vacuum motor.

[0106] As an example, when the vacuum motor drives the motion component to rotate through the transmission assembly, the motion component is spatially limited by the vacuum bearing; when the vacuum motor drives the motion component to translate through the transmission assembly, the motion component is spatially limited by the linear vacuum bearing and the guide rail.

[0107] Specifically, in this embodiment, the vacuum motor drives the motion component to rotate via the transmission assembly. The motion component is spatially constrained by a vacuum bearing. During sample transfer within a vacuum, the sample needs to be inserted and removed from the sample fixing slot 18, which exerts a significant force on the motion component. This force is ultimately applied to the mechanical component of the fixed vacuum bearing via the vacuum bearing. Since the vacuum motor does not directly contact the motion component, it does not experience this force and is therefore less prone to damage. In other words, the vacuum bearing and the mechanical component of the fixed vacuum bearing provide spatial constraint and support for the rotating component, ensuring that the vacuum motor is not subjected to force during sample loading or removal. This effectively solves the problem of easy breakage of vacuum motors under stress in the prior art. The aforementioned vacuum bearing includes one or a combination of ceramic vacuum bearings, polymer vacuum bearings, metal vacuum bearings, and magnetic levitation vacuum bearings.

[0108] It is worth mentioning that, in practical applications, each component involved in this embodiment can be a physical unit, a part of a physical unit, or a combination of multiple physical units. Furthermore, to highlight the innovative aspects of this invention, this embodiment does not introduce units that are not closely related to solving the technical problem proposed by this invention; however, this does not mean that other units are absent from this embodiment.

[0109] Example 2

[0110] Please see Figure 2 It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0111] The difference between Example 2 and Example 1 is that the multidimensional motion is a two-dimensional translational motion, and the specific connection relationship and structure of the components involved in realizing the two-dimensional translational motion of the low-temperature sample holder are as follows.

[0112] As a specific example, such as Figure 2 As shown, the low-temperature sample holder also includes a substrate 20.

[0113] At least two of the vacuum motors include a first electric linear drive motor 24 and a second electric linear drive motor 25; at least two of the transmission components include a first linear transmission component 26, a second linear transmission component 27, an orthogonal translational transmission component one 28, and an orthogonal translational transmission component two 29; at least two of the motion components include a first translational component 22 and a second translational component 23; wherein...

[0114] The first electric linear drive motor 24 is fixed to the substrate 20; the first linear transmission assembly 26 is fixed to the substrate 20 via a vacuum bearing, and the first linear transmission assembly 26 can rotate relative to the substrate 20; the first translation assembly 22 is fixed to the substrate 20 via a linear vacuum bearing, and the first translation assembly 22 can perform translational movement along the X direction; the first electric linear drive motor 24 drives the first translation assembly 22 and all components fixed to the first translation assembly 22 via the first linear transmission assembly 26 to achieve translational movement relative to the substrate 20 along the X direction;

[0115] The second electric linear drive motor 25 is fixed to the substrate 20; the second linear transmission assembly 27 is fixed to the substrate 20 via a vacuum bearing, and the second linear transmission assembly 27 can rotate relative to the substrate 20; the first orthogonal translation transmission assembly 28 is fixed to the substrate 20 via a linear vacuum bearing, and the first orthogonal translation transmission assembly 28 can realize translational movement along the X direction; the second orthogonal translation transmission assembly 29 is fixed to the first translation assembly 22 via a vacuum bearing, and the second orthogonal translation transmission assembly 29 can rotate relative to the first translation assembly 22; the second translation assembly 23 is fixed to the substrate 20 via a linear vacuum bearing. A vacuum bearing is fixed to the first translation component 22. The second translation component 23 can translate relative to the first translation component 22 in the Y direction. The second electric linear drive motor 25 drives the orthogonal translation transmission component 1 28 to translate in the X direction through the second linear transmission component 27. The movement of the orthogonal translation transmission component 1 28 is then driven by the orthogonal translation transmission component 29 to drive the second translation component 23 and all components fixed to the second translation component 23 to translate relative to the first translation component 22 in the Y direction. The X direction and the Y direction are two different directions in the same plane.

[0116] The sample fixing groove 30 is fixed on the second translation component 23.

[0117] Specifically, such as Figure 2 As shown, the first translation component 22 is fixed to the substrate 20 via a first linear vacuum bearing 211, the orthogonal translation transmission component 28 is fixed to the substrate 20 via a second linear vacuum bearing 212, and the second translation component 23 is fixed to the first translation component 22 via a third linear vacuum bearing 213.

[0118] It should be noted that, in order to highlight the innovative aspects of this invention, no units that are not closely related to solving the technical problems proposed by this invention have been introduced in this embodiment. However, this does not mean that there are no other units in this embodiment.

[0119] Based on the above structural description, when the first electric linear drive motor 24 drives the first translation component 22 and all components fixed thereon to move linearly, if the second electric linear drive motor 25 remains stationary, the sample fixing groove 30 will simultaneously move linearly along the Y direction while moving linearly along the X direction, as detailed below. Since the second translation component 23 is fixed to the first translation component 22 via a linear vacuum bearing, when the first translation component 22 moves linearly relative to the substrate 20 along the X direction, the second translation component 23 will simultaneously move linearly along the X direction. Since the orthogonal translation transmission component 28 is fixed to the substrate 20 via a linear vacuum bearing and engages with the second electric linear drive motor 25 via the second linear transmission component 27, when the second electric linear drive motor 25 remains stationary, the orthogonal translation transmission component 28 will also necessarily remain stationary relative to the substrate 20. The second orthogonal translation transmission component 29 is fixed to the first translation component 22 by a vacuum bearing. It will also move linearly along the X direction along with the first linear transmission component 26 and maintain a meshing relationship with the first orthogonal translation transmission component 28. Therefore, the second orthogonal translation transmission component 29 will inevitably have an accompanying rotational motion, driving the second translation component 23 to produce a linear motion along the Y direction.

[0120] To prevent interference between the second translation component 23 and the orthogonal translation transmission component 28, they are placed on different planes. The second orthogonal translation transmission component 29 spans two planes and can simultaneously maintain engagement with the second translation component 23 and the first orthogonal translation transmission component 28 on different planes.

[0121] For the sample fixing groove 30 to achieve independent linear movement along the X direction, the first electric linear drive motor 24 and the second electric linear drive motor 25 must simultaneously drive the first translation component 22 and the orthogonal translation transmission component 28 in a certain relationship to counteract the accompanying movement.

[0122] When the second electric linear drive motor 25 drives the second translation component 23 and all components fixed thereon to move linearly, the sample fixing groove 30 can achieve independent linear movement along the Y direction.

[0123] Specifically, in this embodiment, the vacuum motor drives the corresponding motion component to rotate through the corresponding transmission component, and the motion component is spatially limited by the vacuum bearing; the vacuum motor drives the corresponding motion component to translate through the corresponding transmission component, and the motion component is spatially limited by the linear vacuum bearing and guide rail (not shown). The beneficial effects that can be achieved can be found in the description of Embodiment 1, and will not be repeated here.

[0124] As can be seen from the above structural description, in this embodiment, the first electric linear drive motor 24 and the second electric linear drive motor 25 are both fixed on the base plate 20. Therefore, when the vacuum motor drives the motion component to move through the transmission component, there is no relative movement between the first electric linear drive motor 24 and the second electric linear drive motor 25.

[0125] In practical applications, motion mechanisms involving rotational motion as shown in Embodiment 1 and / or motion mechanisms involving translational motion as shown in Embodiment 2 can be combined in multiple ways to achieve multi-degree-of-freedom linear and rotational motions to meet different needs.

[0126] In summary, this invention provides a low-temperature sample holder housed within a vacuum chamber. The low-temperature sample holder includes a motion mechanism, a cooling device, and a sample fixing slot. The motion mechanism includes at least two vacuum motors, at least two transmission components, and at least two motion components. The sample fixing slot is fixed to the motion components and connected to the cooling device via a heat transfer component. The vacuum motors drive the corresponding motion components through their respective transmission components to achieve multi-dimensional motion of the sample fixing slot and the sample relative to the vacuum chamber. The heat conduction channel between the motion mechanism and the sample fixing slot and the room temperature environment is composed only of low thermal conductivity wires. When the vacuum motors drive the corresponding motion components through their respective transmission components, there is no relative motion between the at least two vacuum motors. By eliminating the mutual motion between the at least two vacuum motors, the influence of the gravitational torque of the vacuum motors on the sample motion is eliminated, significantly reducing the torque requirement of the vacuum motors. The heat conduction channel between the motion mechanism and the sample fixing slot and the room temperature environment is composed only of low thermal conductivity wires, effectively reducing heat conduction between the low-temperature components and the external room temperature environment, thus achieving a lower sample temperature. Compared with existing technologies, this invention reduces the demand for motor drive torque and increases the long-term operational reliability of the cryogenic sample holder. Therefore, this invention effectively overcomes the various shortcomings of existing technologies and has high industrial application value.

[0127] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A low-temperature sample holder, housed within a vacuum chamber, characterized in that, The low-temperature sample holder includes: a cooling device, a sample fixing slot, and a motion mechanism; wherein... The refrigeration device provides a low-temperature cold source; The motion mechanism includes at least two vacuum motors, at least two transmission components, and at least two motion components. The sample fixing slot is fixed to the motion components. The sample fixing slot is connected to the refrigeration device through a heat transfer component. The vacuum motors drive the motion components to move through the transmission components, so as to realize multi-dimensional movement of the sample fixing slot and the sample fixed therein relative to the vacuum chamber. The heat conduction channel between the motion mechanism and the sample fixing slot and the room temperature environment is only composed of low thermal conductivity wires. At least two of the motion components include a first rotating component, and at least two of the vacuum motors are fixed to the first rotating component. When the vacuum motors drive the motion components to move, no relative motion occurs between the at least two vacuum motors.

2. A low-temperature sample holder, housed within a vacuum chamber, characterized in that, The low-temperature sample holder includes: a cooling device, a sample fixing slot, and a motion mechanism; wherein... The refrigeration device provides a low-temperature cold source; The motion mechanism includes at least two vacuum motors, at least two transmission components, and at least two motion components. The sample fixing slot is fixed to the motion components. The sample fixing slot is connected to the refrigeration device through a heat transfer component. The vacuum motors drive the motion components to move through the transmission components, so as to realize multi-dimensional movement of the sample fixing slot and the sample fixed therein relative to the vacuum chamber. The heat conduction channel between the motion mechanism and the sample fixing slot and the room temperature environment is only composed of low thermal conductivity wires. The low-temperature sample holder also includes a substrate, and at least two of the vacuum motors are fixed on the substrate. When the vacuum motors drive the motion component to move, there is no relative motion between the at least two vacuum motors.

3. The low-temperature sample holder according to claim 1 or 2, characterized in that: The motion component is equipped with a counterweight to adjust the overall center of gravity of the motion component and all components fixed to the motion component to the axis of rotation of the motion component.

4. The low-temperature sample holder according to claim 1 or 2, characterized in that: The vacuum motor is a vacuum motor with a position encoder. The vacuum motor is connected to a motor controller located outside the vacuum chamber via the low thermal conductivity wire to control the movement of the motion component. The low thermal conductivity wire includes one or more combinations of constantan wire, manganese copper wire, and German silver wire.

5. The low-temperature sample holder according to claim 1 or 2, characterized in that: The vacuum motor includes one or more combinations of ceramic vacuum motors, electromagnetic vacuum motors, electrostatic vacuum motors, magnetostrictive vacuum motors, and shape memory alloy vacuum motors.

6. The low-temperature sample holder according to claim 1 or 2, characterized in that: The sample is inserted into the sample fixing groove and pressed tightly onto the sample fixing groove by a spring plate or threaded fastener.

7. The low-temperature sample holder according to claim 1 or 2, characterized in that: The transmission assembly includes one or more combinations of transmission rods, gears, racks, worm gears, worm shafts, lead screws, timing belts, flexible chains, flexible shafts, and universal joints.

8. The low-temperature sample holder according to claim 1 or 2, characterized in that: The heat transfer component is a flexible heat transfer component, and its two ends are respectively connected to the sample fixing groove and the cooling device. Alternatively, the heat transfer component may include a flexible heat transfer component and a rigid heat transfer component, wherein one end of the rigid heat transfer component is connected to the refrigeration device, the other end is connected to one end of the flexible heat transfer component, and the other end of the flexible heat transfer component is connected to the sample fixing groove.

9. The low-temperature sample holder according to claim 8, characterized in that: The rigid heat transfer component is made of a thermally conductive material, while the flexible heat transfer component is made of thermally conductive material wires or thermally conductive material foils.

10. The low-temperature sample holder according to claim 1 or 2, characterized in that: The transmission component is made of a thermally conductive material, and the motion component is made of a thermally conductive material.

11. The low-temperature sample holder according to claim 1 or 2, characterized in that: It also includes a heat shield; the cooling device includes a primary cold end with a higher temperature and a secondary cold end with a lower temperature, the motion mechanism and the sample fixing groove are fixed to the secondary cold end, one end of the heat transfer component is connected to the secondary cold end and the other end is connected to the sample fixing groove, the end of the heat shield is fixed to the primary cold end, the heat transfer component, the secondary cold end and all components fixed to the secondary cold end are housed in the heat shield, wherein the higher temperature is lower than room temperature, the lower temperature is lower than the higher temperature, and the material of the heat shield is a thermally conductive material.

12. The low-temperature sample holder according to claim 1 or 2, characterized in that: The connection between the heat transfer component and the refrigeration device is provided with an insulating high thermal conductivity material, which includes one or more combinations of insulating carbon-based materials, high thermal conductivity ceramics, high thermal conductivity insulating crystals, and high thermal conductivity insulating composite materials.

13. The low-temperature sample holder according to claim 12, characterized in that: The high thermal conductivity insulating crystal includes one or more combinations of Al2O3 crystal and TiO2 crystal.

14. The low-temperature sample holder according to claim 1 or 2, characterized in that: The connection points of each component in the low-temperature sample holder are all provided with highly ductile thermally conductive materials, which include one or more combinations of indium, silver, gold, carbon-based flexible highly thermally conductive materials and flexible highly thermally conductive composite materials.

15. The low-temperature sample holder according to claim 1 or 2, characterized in that: The refrigeration device includes one or more combinations of GM refrigerators, Stirling refrigerators, liquid helium refrigerators, dilution refrigerators, pulse tube refrigerators, magnetic refrigerators, adsorption refrigerators, thermoelectric refrigerators, and liquid helium cold traps.

16. The low-temperature sample holder according to claim 1 or 2, characterized in that: It also includes a thermometer, which is housed within the vacuum chamber and connected to a temperature controller located outside the vacuum chamber via the low thermal conductivity wire.

17. The low-temperature sample holder according to claim 16, characterized in that: The thermometer includes one or more combinations of resistance thermometers, diode thermometers, thermocouple thermometers, and magnetic susceptibility thermometers.

18. The low-temperature sample holder according to claim 1 or 2, characterized in that: The transmission component and the motion component have a hollow structure or a reinforcing rib structure.

19. The low-temperature sample holder according to claim 1 or 2, characterized in that: When the vacuum motor drives the motion component to rotate through the transmission assembly, the motion component is spatially limited by the vacuum bearing. When the vacuum motor drives the motion component to perform translational motion through the transmission assembly, the motion component is spatially limited by the linear vacuum bearing and guide rail.

20. The low-temperature sample holder according to claim 19, characterized in that: The vacuum bearing includes one or more combinations of ceramic vacuum bearings, polymer vacuum bearings, metal vacuum bearings, and magnetic levitation vacuum bearings.

21. The low-temperature sample holder according to claim 1 or 2, characterized in that: The multidimensional motion includes one or more combinations of multidimensional rotational motion and multidimensional translational motion.

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