Mechanical thermal switch and probe station

Abstract

The application provides a mechanical thermal switch, comprising a primary cold conducting connection part, a first secondary cold conducting connection part, a second secondary cold conducting connection part, a cold conducting switching part and a control part, the first secondary cold conducting connection part and the second secondary cold conducting connection part are arranged at intervals, the primary cold conducting connection part is in cold conducting connection with the cold conducting switching part, the control part is configured in a form capable of driving the cold conducting switching part to move, and the control part controls the cold conducting switching part to switch a cold conducting path. The application also provides a probe station using the mechanical thermal switch.

Description

Technical Field

[0001] This invention belongs to the field of probe testing technology and relates to the switching of cooling paths, specifically to a mechanical thermal switch. Background Technology

[0002] Probe station testing equipment is a widely used non-destructive testing method with extensive applications in physics and semiconductor fields. In practical applications, since some tested materials or devices are used in cryogenic environments, it is necessary to test their performance at low temperatures. Therefore, the sample in the probe station needs to be kept in a cryogenic environment. To meet certain special testing requirements, such as the performance of the tested object in a strong magnetic field environment, superconducting coils are often used to generate the required magnetic field, such as in cryogenic superconducting magnetic field probe stations. In this case, both the sample and the superconducting coil in the cryogenic superconducting magnetic field probe station need to be cooled to a cryogenic temperature. Because both the sample and the superconducting coil need to be cooled, they are usually cooled together. Summary of the Invention

[0003] Because superconducting coils must operate at the superconducting transition temperature, while the temperature of the sample under test varies within a range from liquid helium temperature to room temperature and even higher, when the sample is at a low temperature, it shares a cooling source with the superconducting magnet. When the sample requires a higher temperature, the temperature of the superconducting coil will rise, causing it to malfunction. In other words, directly connecting the superconducting coil to the sample limits the temperature range of the sample to be tested, significantly reducing the testing temperature range and the applicability of the equipment.

[0004] To avoid the limitation between the temperature range of the superconducting coil and the measured object, this invention first provides a mechanical thermal switch. Structurally, it includes a primary cooling connection, a second-stage cooling connection, a cooling switching unit, and a control unit. The first-stage and second-stage cooling connections are spaced apart. The primary cooling connection is thermally connected to the cooling switching unit. The control unit is configured to move the cooling switching unit and controls the cooling switching unit to switch between the following states:

[0005] First state: The cooling switching part is in contact with the first-stage cooling connection part;

[0006] Second state: There is no surface contact between the cooling switching part and the first-stage cooling connection part, and there is no surface contact between the cooling switching part and the second-stage cooling connection part;

[0007] Third state: The cooling switching part is in surface contact with the second-stage cooling connection part.

[0008] Preferably, in the second state, a gap is provided between the cold conducting switch and the first secondary cold conducting connection, and a gap is provided between the cold conducting switch and the second secondary cold conducting connection.

[0009] Optionally, in the second state, the cold conducting switch is in line contact with the first secondary cold conducting connection, and the cold conducting switch is in line contact with the second secondary cold conducting connection.

[0010] Preferably, the mechanical thermal switch further comprises an operating part, the operating part comprising a push rod, a ball head, and a ball bowl, a concave surface of the ball bowl matching a convex surface of the ball head, the ball bowl being connected with the control part, the ball head being in transmission connection with the push rod, the ball head and the ball bowl being configured to change between a contact state and a separation state.

[0011] Further preferably, the operating part further comprises a first elastic member, the first elastic member pushing the ball bowl away from the first secondary cold conducting connection.

[0012] Further preferably, the operating part further comprises a ball head seat and a second elastic member, the ball head being in transmission connection with the push rod through the ball head seat, the ball head seat being in limit connection with the ball head in a direction of movement of the ball head, the second elastic member pushing the ball head away from the ball head seat.

[0013] Still further preferably, the push rod is a screw rod, the operating part further comprising a first plate, a bearing, and a bearing seat, the push rod being in threaded connection with the first plate, the push rod being connected with the bearing, the bearing seat being connected with the ball head seat, two end surfaces of the bearing being limited and fixed by the bearing seat and the ball head seat.

[0014] Optionally, the cold conducting switch is provided with a cold conducting assembly connecting end, the first secondary cold conducting connection being provided with a first through hole, the cold conducting assembly connecting end passing through the first through hole and being in cold conducting connection with the primary cold conducting connection.

[0015] Preferably, the cold conducting switch is generally shuttle-shaped, the cold conducting switch being provided with a first contact surface and a second contact surface at two ends thereof respectively, widths of cross sections of the first contact surface and the second contact surface gradually decreasing from a middle part of the cold conducting switch to the two ends thereof respectively.

[0016] Preferably, the cold conducting switch comprises a first contact surface, a second contact surface, and a connecting frame connecting the first contact surface and the second contact surface, the first contact surface and the second contact surface being oppositely arranged, the first contact surface and the second contact surface being protruded from the connecting frame.

[0017] Optionally, the first contact surface and the second contact surface can be conical frustum, prism frustum, cone, or pyramid.

[0018] Optionally, the first cold conducting surface and the second cold conducting surface can be wedge-shaped grooves, and the first contact surface and the second contact surface are respectively matched with the shape of the corresponding wedge-shaped grooves.

[0019] Further preferably, the first secondary cold conducting connection is provided with a first cold conducting surface matched with the first contact surface, and the second secondary cold conducting connection is provided with a second cold conducting surface matched with the second contact surface.

[0020] In the first state, the first cold conducting surface is in surface contact with the first contact surface.

[0021] In the third state, the second cold conducting surface is in surface contact with the second contact surface.

[0022] Preferably, in the second state, the first cold conducting surface and the first contact surface are separated from each other, and the second cold conducting surface and the second contact surface are separated from each other.

[0023] The application also provides a probe station, comprising a magnetic field generator, a sample support device, a probe assembly, a cold source, and a mechanical thermal switch, the magnetic field generator is in cold connection with the first secondary cold conducting connection, the sample support device is in cold connection with the second secondary cold conducting connection, and the primary cold conducting connection is in cold connection with the cold source.

[0024] Preferably, the probe station further comprises a housing, the magnetic field generator, the sample support device, the primary cold conducting connection, the first secondary cold conducting connection, the second secondary cold conducting connection, and the cold conducting switch are located inside the housing, and the control unit, the probe assembly, and the cold source are at least partially located inside the housing, and the inside of the housing is vacuum.

[0025] Preferably, the two ends of the cold conducting switch are respectively provided with a first contact surface and a second contact surface, the first secondary cold conducting connection is provided with a first cold conducting surface matched with the first contact surface, and the second secondary cold conducting connection is provided with a second cold conducting surface matched with the second contact surface; in the first state, the first cold conducting surface is in surface contact with the first contact surface; and in the third state, the second cold conducting surface is in surface contact with the second contact surface.

[0026] Further preferably, when switching between the first state, the second state, and the third state, the cold conducting switch moves in the horizontal direction.

[0027] Further preferably, a distance between the first contact surface and the first cold conducting surface perpendicular to the moving direction of the cold conducting switch part is d1, a maximum value of d1 is D1; a distance between the second contact surface and the second cold conducting surface perpendicular to the moving direction of the cold conducting switch part is d2, a maximum value of d2 is D2; the first secondary cold conducting connection part is provided with a first through hole through which a cold conducting component joint end on the cold conducting switch part can pass, a distance between the first through hole and the cold conducting component joint end is d3, a maximum value of d3 is D3, the second secondary cold conducting connection part is provided with a second through hole through which the control part can pass, a distance between the second through hole and the control part is d4, a maximum value of d4 is D4; wherein D3 < max(D1, D2), D4 < max(D1, D2).

[0028] The application further provides another probe station comprising a sample support device, a probe assembly, a first cold source, a second cold source, and a mechanical thermal switch, the first cold source is in cold conducting connection with the first secondary cold conducting connection part, the second cold source is in cold conducting connection with the second secondary cold conducting connection part, and the primary cold conducting connection part is in cold conducting connection with the sample support device.

[0029] The mechanical thermal switch provided by the application has at least the following beneficial effects: through the switching of the first state, the second state and the third state, the switching between the cold conducting to the first secondary cold conducting connection part, the non-cold conducting or the less cold conducting, and the cold conducting to the second secondary cold conducting connection part can be realized, and the cold conducting path can be selected as needed, and the switching of the cold conducting path in a narrow space can be realized.

[0030] The probe station provided by the application has at least the following beneficial effects: the switching of the cold conducting path under a single cold source can be realized, the mutual influence of the temperature between the magnetic field generator and the sample is avoided, the cold conducting path can be selected as needed, and the temperature change of the sample to be measured in the full temperature range can be realized; or the rapid switching between different cold sources can be realized, and the temperature control speed is improved. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the mechanical thermal switch.

[0032] Figure 2 It is a schematic diagram of the overall structure of an embodiment of the mechanical thermal switch. Figure 1 It is an A-A sectional view of the mechanical thermal switch.

[0033] Figure 3 It is an enlarged view of the B part of the mechanical thermal switch. Figure 2 It is an enlarged view of the B part of the mechanical thermal switch.

[0034] Figure 4 It is a schematic diagram of the mechanical thermal switch in the first state.

[0035] Figure 5Schematic diagram of mechanical thermal switch in second state.

[0036] Figure 6 Schematic diagram of mechanical thermal switch in third state.

[0037] Figure 7 Schematic diagram of mechanical thermal switch in second state. Figure 5 Schematic diagram of mechanical thermal switch in second state.

[0038] Figure 8 Schematic diagram of mechanical thermal switch in second state.

[0039] Figure 9 Schematic diagram of mechanical thermal switch in second state.

[0040] Figure 10 Schematic diagram of mechanical thermal switch in second state. DETAILED DESCRIPTION

[0041] In order to make the purpose and features of the present application more obvious and easy to understand, the specific embodiments of the present application are further described below in combination with the drawings. It should be noted that the drawings are all very simplified and use non-precise ratios, and are only used for the purpose of conveniently and clearly assisting the description of the embodiments of the present application.

[0042] Referring to Figures 1 to 6 , the present application provides a mechanical thermal switch, comprising a primary cold conducting connection part 100, a first secondary cold conducting connection part 200, a second secondary cold conducting connection part 300, a cold conducting switching part 400, and a control part 500, the first secondary cold conducting connection part 200 and the second secondary cold conducting connection part 300 are arranged at intervals, the cold conducting switching part 200 is connected with the control part 500, the control part 500 is configured to drive the cold conducting switching part 400 to move, and the control part 500 controls the cold conducting switching part 400 to switch between the following states:

[0043] As shown in the first state in Figure 4 , the cold conducting switching part 400 is in surface contact with the first secondary cold conducting connection part 200;

[0044] As shown in the second state in Figure 5 , the cold conducting switching part 400 is not in surface contact with the first secondary cold conducting connection part 200, and the cold conducting switching part 400 is not in surface contact with the second secondary cold conducting connection part 300;

[0045] As shown in the third state in Figure 6 , the cold conducting switching part 400 is in surface contact with the second secondary cold conducting connection part 300.

[0046] Referring to Figures 4-6In the first state, there is a gap between the cooling switching part 400 and the secondary cooling connection part 300, or only line contact or point contact exists between them. This results in the cooling efficiency between the cooling switching part 400 and the secondary cooling connection part 300 being much lower than the cooling efficiency between the cooling switching part 400 and the primary cooling connection part 200. Similarly, in the third state, there is a gap between the cooling switching part 400 and the primary cooling connection part 200, or only line contact or point contact exists between them. This again results in the cooling efficiency between the cooling switching part 400 and the primary cooling connection part 200 being much lower than the cooling efficiency between the cooling switching part 400 and the secondary cooling connection part 300.

[0047] Please see Figure 5 In the second state, such as Figure 5 The second state shown is as follows: there is no surface contact between the cooling switching part 400 and the first-stage cooling connection part 200, and there is no surface contact between the cooling switching part 400 and the second-stage cooling connection part 300. That is to say, the cooling switching part 400 can be in point contact, line contact, or spaced apart from the first-stage cooling connection part 200 and the second-stage cooling connection part 300. In this way, the heat exchange efficiency between the cooling switching part 400 and the first-stage cooling connection part 200 and the second-stage cooling connection part 300 is greatly reduced, thereby forming a cooling isolation or near-isolation effect between the primary cooling connection part 100, the first-stage cooling connection part 200, and the second-stage cooling connection part 300.

[0048] More specifically, when this mechanical thermal switch is applied to a test device under low-temperature conditions, the primary cooling connection 200 and the secondary cooling connection 300 are respectively connected to the superconducting coil and the sample stage for cooling. For example, the primary cooling connection 200 is connected to the superconducting coil for cooling via its cooling connection end 202, and the secondary cooling connection 300 is connected to the sample stage for cooling via its cooling connection end 302. Figures 4-6 As shown, the cooling connection ends 202 and 302 can be connected to a cooling chain, which can be fixed by the cooling chain mounting screws provided on the cooling connection ends 202 and 302. The cooling chain can be a group of heat-conducting metal wires.

[0049] Please see Figures 4 to 6The cold conducting switch 400 is generally in the shape of a shuttle, and the first secondary cold conducting connection 200 and the second secondary cold conducting connection 300 are arranged on both sides of the cold conducting switch 400. The cold conducting switch 400 is provided with a first contact surface 401 and a second contact surface 402 at both ends thereof, and the cross-sectional width of each of the first contact surface 401 and the second contact surface 402 gradually decreases from the middle part of the cold conducting switch 400 to both ends thereof. The first secondary cold conducting connection 200 is provided with a first cold conducting surface 201 matched with the first contact surface 401, and the second secondary cold conducting connection 300 is provided with a second cold conducting surface 301 matched with the second contact surface 402. As an optional mode, the first contact surface 401 and the second contact surface 402 are both in the shape of a tapered truncated cone, and the larger base of the tapered truncated cone of each of the first contact surface 401 and the second contact surface 402 is connected to each other. In addition, the first contact surface 401 and the second contact surface 402 can also be in the shape of a pyramid, a truncated pyramid or a pyramid, as long as the cold conducting switch 400 can realize the switching among the first state, the second state and the third state. Correspondingly, the first cold conducting surface 201 and the second cold conducting surface 301 can be in the shape of a wedge-shaped groove, and the first contact surface 401 and the second contact surface 402 are matched with the shape of the corresponding wedge-shaped groove.

[0050] The primary cold conducting connection 100 can be connected with the cold source or the load. Specifically, please refer to Figure 1 The primary cold conducting connection 100 comprises a first end 101 and a second end 102, the first end 101 is connected with the cold source or the load, and the second end 102 is connected with the cold conducting switch 400. The part between the first end 101 and the second end 102 of the primary cold conducting connection 100 can be in the form of a heat conducting metal wire group, for example, in the form of a cable wound by copper wires. The first end 101 and the second end 102 are respectively provided with corresponding fixing structures for fixing, for example, screw holes are arranged on the first end 101 and the second end 102 respectively, so that the first end 101 and the second end 102 are connected and fixed by screws.

[0051] Since the primary cold conducting connection 100 is connected with one of the cold source or the load and the cold conducting switch 400, the primary cold conducting connection 100 can conduct cold energy between the cold source and the cold conducting switch 400 or between the load and the cold conducting switch 400. Please refer to Figure 4, the first contact surface 401 of the cold conducting switch 400 is in surface contact with the first cold conducting surface 201 of the first secondary cold conducting connection 200, so that the cold conducting switch 400 and the first secondary cold conducting connection 200 have high cold conducting efficiency, and the cold conducting switch 400 and the primary cold conducting connection 100 have high cold conducting efficiency, thereby forming a cold energy transmission path of the primary cold conducting connection 100, the cold conducting switch 400 and the first secondary cold conducting connection 200. In the second state, the cold conducting switch 400 is not in surface contact with the first secondary cold conducting connection 200 and the second secondary cold conducting connection 300, i.e. only in line contact, point contact or no contact, so that the cold conducting efficiency between the cold conducting switch 400 and the first secondary cold conducting connection 200 and the cold conducting efficiency between the cold conducting switch 400 and the first secondary cold conducting connection 200 are very low or cannot conduct cold, at this time, the cold energy transmission paths between the first secondary cold conducting connection 200 and the cold conducting switch 400 and between the second secondary cold conducting connection 300 and the cold conducting switch 400 are disconnected. In the third state, the second contact surface 402 of the cold conducting switch 400 is in surface contact with the second cold conducting surface 301 of the second secondary cold conducting connection 300, so that the cold conducting switch 400 and the second secondary cold conducting connection 300 have high cold conducting efficiency, and the cold conducting switch 400 and the primary cold conducting connection 100 have high cold conducting efficiency, thereby forming a cold energy transmission path of the primary cold conducting connection 100, the cold conducting switch 400 and the second secondary cold conducting connection 300. It can be understood that the components connected on the first secondary cold conducting connection 200 and the second secondary cold conducting connection 300 can be selected as needed, for example, according to the needs, the cold sources, magnetic field generators, sample support devices, probe assemblies and cold screens and other components that need to be controlled at a certain temperature are connected on the first secondary cold conducting connection 200 and the second secondary cold conducting connection 300.

[0052] The position of the cold conducting switch 400 is controlled by the control part 500. Please refer to Figure 1 、 Figure 2 The control part 500 is fixedly connected with the cold conducting switch 400, and the fixed connection mode can be screw connection, gluing, clamping, limiting connection and the like, and only needs to make the cold conducting switch 400 can be switched between the first state, the second state and the third state under the action of the control part 500. Figure 2 A control part 500 is shown in a mode of being connected with the cold conducting switch 400 by screw connection.

[0053] Please refer to Figure 2The cold conducting switch 400 is provided with a cold conducting assembly connecting end 403, the first secondary cold conducting connecting part 200 is provided with a first through hole 203, the cold conducting assembly connecting end 403 passes through the first through hole 203 and is connected with the primary cold conducting connecting part 100. More specifically, a gap is provided between the cold conducting assembly connecting end 403 and the first through hole 203.

[0054] Please refer to Figures 4 to 6 As an optional form, the cold conducting switch 400 in the first state, the second state and the third state is always on the same axis, which is the first axis. Correspondingly, the control part 500 moves along the direction parallel to the first axis. As an optional implementation, the control part 500 is a long rod, one end 501 of the control part 500 is connected with the cold conducting switch 400. At this time, further, the second secondary cold conducting connecting part 300 is provided with a second through hole 303 for accommodating the control part 500, and the control part 500 moves in the second through hole 303.

[0055] Please refer to Figure 7 The distance between the first contact surface 401 and the first cold conducting surface 201 in the direction perpendicular to the first axis is d1, and the maximum value of d1 is D1; the distance between the second contact surface 402 and the second cold conducting surface 301 in the direction perpendicular to the first axis is d2, and the maximum value of d2 is D2; the distance between the first through hole 203 of the first secondary cold conducting connecting part 200 and the cold conducting assembly connecting end 403 is d3, and the maximum value of d3 is D3; the distance between the second through hole 303 of the second secondary cold conducting connecting part 300 and the control part 500 is d4, and the maximum value of d4 is D4. More specifically, D3 < max(D1, D2), D4 < max(D1, D2). Preferably, D3 = D4 = 2mm. It can be understood that in the first state, d1 = 0, d2 = D2; in the third state, d2 = 0, d1 = D1; in the second state, 0 < d1 < D1, 0 < d2 < D2. Preferably, D1 = D2 = 3mm.

[0056] Please refer to Figure 2 The mechanical thermal switch further comprises an operating part 600, the operating part 600 comprises a push rod 620, a ball head 630, and a ball bowl 640, the concave surface of the ball bowl 640 matches the convex surface of the ball head 630, the ball bowl 640 is connected with the control part 500, the ball head 630 is in transmission connection with the push rod 620, and the ball head 630 and the ball bowl 640 are configured in a form capable of changing between the contact state and the separation state; the operating part 600 further comprises a first elastic member 642, and the first elastic member 642 pushes the ball bowl 640 away from the first secondary cold conducting connecting part 200.

[0057] Figure 3The detailed features of the operation part 600 are shown. The push rod 620 is in transmission connection with the ball head 630, and the ball head 630 can be moved by operating the push rod 620, and then the ball head 630 is in contact with or separated from the ball bowl 640. When the push rod 620 drives the ball head 630 to move towards the ball bowl 640, the ball head 630 gradually approaches the ball bowl 640, and finally contacts the ball bowl 640. Then, the push rod 620 further drives the ball head 630 to move towards the ball bowl 640, so that the ball head 630 moves together with the ball bowl 640, and drives the control part 500 to move, and then drives the cold guide switching part 400 to move, for example, drives the cold guide switching part 400 to switch from the second state to the first state, or from the third state to the second state. When the push rod 620 drives the ball head 630 to move away from the ball bowl 640, the ball bowl 640 is still in contact with the ball head 630 under the drive of the first elastic member 642, and moves together with the ball head 630 away from the first secondary cold guide connection part 200, and at the same time drives the cold guide switching part 400 to move, for example, drives the cold guide switching part 400 to switch from the first state to the second state, or from the second state to the third state. When the cold guide switching part 400 is in the third state, the cold guide switching part 400 is limited by the second secondary cold guide connection part 300, at this time, the ball bowl 640 is also limited because it is connected with the cold guide switching part 400 through the control part 500, and cannot further move away from the first secondary cold guide connection part 200, the ball head 630 continues to move away from the first secondary cold guide connection part 200, and then the ball head 630 and the ball bowl 640 are separated from each other. The switching of the first state, the second state and the third state is completed.

[0058] Please refer to Figure 2 , the push rod 620 is a screw rod, the operation part 600 further comprises a first plate 611, a bearing 641, a bearing seat 650, a ball head seat 672, the push rod 620 is in threaded connection with the first plate 611, the fixed end 621 of the push rod 620 is connected with the bearing 641, the bearing seat 650 is connected with the ball head seat 672, the two end faces of the bearing 641 are limited and fixed by the bearing seat 650 and the ball head seat 672, and the ball head seat 672 is connected with the ball head 630. More specifically, the inner ring of the bearing 641 is fixed to one end of the push rod 620 through a bearing retainer 642, the outer ring of the bearing 641 is arranged inside the bearing seat 650, the bearing seat 650 is connected with the ball head seat 672, a cavity is formed between the bearing seat 650 and the ball head seat 672, the bearing 641 is located in the cavity and is limited from the two end faces by the bearing seat 650 and the ball head seat 672. As shown in Figure 2 , the ball head seat 672 is provided with a groove accommodating the bearing retainer 642 at the position corresponding to the bearing retainer 642.

[0059] Please refer to Figure 3, the ball head 630 is limited to the limit position close to the ball bowl 640. The ball head seat 672 drives the ball head 630 to continue to move towards the ball bowl 640, so that the ball head 630 gradually contacts the ball bowl 640. Subsequently, the ball head seat 672 continues to move towards the ball bowl 640 under the transmission action of the push rod 620, when the elastic coefficient of the first elastic member 642 is less than that of the second elastic member 632, the deformation of the first elastic member 642 is greater than that of the second elastic member 632, the ball head 630 and the ball bowl 640 still move to the side of the ball bowl 640 under the action of the second elastic member 632, that is, move to the direction of the first secondary cold conduction connecting part 200. When the cold conduction switching part 400 is in the first state, that is, the cold conduction switching part 400 contacts the first secondary cold conduction connecting part 200, the cold conduction switching part 400 is limited by the first secondary cold conduction connecting part 200, so that the ball bowl 640 connected by the control part 500 is also limited and cannot continue to move close to the first secondary cold conduction connecting part 200. At this time, the first elastic member 642 no longer deforms, and the ball head seat 672 continues to move towards the ball bowl 640, and the second elastic member 632 continues to deform. At this time, since the elastic coefficient of the first elastic member 642 is less than that of the second elastic member 632, the pushing force of the ball head seat 672 to the ball head 630 and the ball bowl 640 jumps before and after this moment, that is, the pushing force suddenly rises, and correspondingly, the driving force required on the push rod 620 will also jump, thereby prompting the occurrence of the first state. Subsequently, the ball head seat 672 continues to move towards the ball bowl 640, at this time, only the second elastic member 632 further deforms, and the pin 674 moves in the through groove 633 to allow the ball head seat 672 to further approach the ball bowl 640. When the pin 674 reaches the edge of the through groove 633, the ball head seat 672 reaches the limit position and cannot further approach the ball bowl 640. When the ball head seat 672 is driven to move away from the ball bowl 640, the specific situation is similar to the foregoing case, which will not be described here.

[0060] Please refer to Figure 2The operation part 600 is further provided with a guide column 660, the bearing seat 650 is provided with a guide groove 652 matched with the guide column 660, and the guide column 660 is arranged in the guide groove 652. Specifically, the guide column 660 is fixedly connected with the first plate 611 and extends from the first plate 611 to the first secondary cold connection part 200, so that the bearing seat 650 cannot rotate under the driving of the inner ring of the bearing 641, and the stability of the transmission process is ensured.

[0061] Please refer to Figure 2 The operation part 600 further includes a second plate 613, an outer cover 612, a bellows seat 671 and 680, the two bellows seats 671 and 680 are oppositely arranged, and a bellows 690 is connected between the two bellows seats 671 and 680. The outer cover 612 is in a cylindrical shape, and the first plate 611 and the second plate 613 are fixedly connected to the two end openings of the outer cover 612 respectively. As shown in Figure 2 , the ball head seat 672 is connected with the bellows seat 671, the second plate 613 is connected with the bellows seat 680, the outer cover 612, the first plate 611 and the second plate 613 form a cavity, and the ball head 630, the ball bowl 640, the bearing 641, the bearing seat 650, the ball head seat 672, the first elastic member 642 and the second elastic member 632 are located in the cavity. Further, the bellows 690, the bellows seats 671 and 680, the first plate 611 and the second plate 613 form another cavity, which is located inside the cavity formed by the outer cover 612, the first plate 611 and the second plate 613. The ball head 630, the ball bowl 640, the first elastic member 642 and the second elastic member 632 are arranged in the cavity formed by the bellows 690, the bellows seats 671 and 680, the first plate 611 and the second plate 613, and the ball head seat 672 and the control wave 500 are partially located in the cavity. The sealing ring 673 is further arranged between the ball head seat 672 and the bellows seat 671, and the sealing ring 673 is further arranged between the second plate 613 and the bellows seat 680.

[0062] Please refer to Figure 2 In order to facilitate operation, a knob 623 can be further connected to the operation end 622 of the push rod 620. Further, an eccentric protrusion can be further arranged on the knob 623, so as to rotate the knob 623 by the eccentric protrusion.

[0063] On the basis of the working mode of the mechanical thermal switch, the mechanical thermal switch can also adopt the form as shown in Figure 8 , specifically, please refer to Figure 8The cold conducting switch 400 comprises a first contact surface 401, a second contact surface 402, and a connecting frame 404 connecting the first contact surface 401 and the second contact surface 402. The first contact surface 401 and the second contact surface 402 are oppositely arranged, and protrude from the connecting frame 404. The first secondary cold conducting connection 200 is provided with a first cold conducting surface 201 matched with the first contact surface 401. The second secondary cold conducting connection 300 is provided with a second cold conducting surface 301 matched with the second contact surface 402. The first cold conducting surface 201 is opened at least on the side close to the first contact surface 401 to accommodate the first contact surface 401. The second cold conducting surface 301 is opened at least on the side close to the second contact surface 402 to accommodate the second contact surface 402. In use, the cold conducting switch 400 is controlled to move by the control unit 500, and the first state, the second state, and the third state are realized. For example, in the first state, the first contact surface 401 of the cold conducting switch 400 is in surface contact with the first cold conducting surface 201 of the first secondary cold conducting connection 200. In the second state, the first contact surface 401 and the second contact surface 402 of the cold conducting switch 400 are not in surface contact with the first secondary cold conducting connection 200 and the second secondary cold conducting connection 300. In the third state, the second contact surface 402 of the cold conducting switch 400 is in surface contact with the second cold conducting surface 301 of the second secondary cold conducting connection 200. The specific control mode of the cold conducting switch 400 is basically the same as the control mode of the cold conducting switch 400 of the magnetic field generator 700, and will not be described here. Figures 4 to 6

[0064] Please refer to Figure 9 The application further provides a probe station comprising a magnetic field generator 700, a sample support device 800, a probe assembly 901, a cold source, and the mechanical thermal switch described above. The magnetic field generator 700 is in cold conducting connection with the first secondary cold conducting connection 200. The sample support device 800 is in cold conducting connection with the second secondary cold conducting connection 300. The primary cold conducting connection 100 is in cold conducting connection with the cold source through the cold conducting chain 110. In this way, the cold energy of the cold source can be transmitted to the sample support device 800 in the first state, the cold energy of the cold source can be transmitted to the magnetic field generator 700 in the third state, and the amount of cold energy transmitted to the magnetic field generator 700 and the sample support device 800 is greatly reduced or no cold energy is transmitted in the second state.

[0065] As Figure 9 ​As shown, the mechanical thermal switch is horizontally placed. Specifically, when switching between the first state, the second state, the third state, the cold conducting switching part 400 moves along the horizontal direction. At this time, when the control part 500 only moves along the horizontal direction, the cold conducting switching part 400 also only moves in the horizontal direction. At this time, the cold conducting switching part 400 in the second state can have a gap between the first secondary cold conducting connection part 200 and the second secondary cold conducting connection part 300. When the control part 500 can move in a certain range in the vertical direction in addition to the movement in the horizontal direction, the cold conducting switching part 400 will move a certain distance downward and approach the first secondary cold conducting connection part 200 and the second secondary cold conducting connection part 300 in the second state. When there is a gap between the first contact surface 401 and the first cold conducting surface 201, and between the second contact surface 402 and the second cold conducting surface 301, that is, when the first contact surface 401 and the first cold conducting surface 201 are completely separated, and the second contact surface 402 and the second cold conducting surface 301 are completely separated, because D3 < max(D1, D2), D4 < max(D1, D2), the cold conducting assembly connecting end 403 will be lapped on the inner wall of the first through hole 203 of the first secondary cold conducting connection part 200, and the control part 500 will be lapped on the inner wall of the second through hole 303 of the second secondary cold conducting connection part 300. At this time, the cold conducting switching part 400 does not have surface contact with the first secondary cold conducting connection part 200 and the second secondary cold conducting connection part 300, but only has a small line contact, which can also greatly reduce the heat conduction efficiency and achieve a similar cold energy isolation effect.

[0066] Please refer to Figure 9 The probe station also includes a housing 902. Specifically, the housing 902 wraps the magnetic field generator 700, the sample support device 800, the primary cold conducting connection part 100, the first secondary cold conducting connection part 200, the second secondary cold conducting connection part 300, and the cold conducting switching part 400 inside, and at least part of the control part 500 and the probe assembly 901 are located inside the housing 902, and the inside 907 of the housing is a vacuum. As Figure 9As shown, the shell 902 forms an external cavity to enable the formation of a vacuum environment. As an embodiment, the magnetic field generator 700 is a ring-shaped electromagnetic coil, and a matching cold shield shell 701 is arranged at the outer periphery of the magnetic field generator 700, which is cold connected with the second secondary cold connection part 300, specifically, the cold connection can be achieved by the cold chain 304 or by direct contact, and the cold connection by the cold chain 304 is preferred. The sample support device 800 is arranged at the inner side of the ring-shaped magnetic field generator 700, and the sample support device 800 is cold connected with the first secondary cold connection part 200, which can be cold connected by the cold chain 204 or by direct contact, and the cold connection by the cold chain 204 is preferred. The magnetic field generator 700 and the sample support device 800 are fixed by corresponding supports 903. The probe module 901 extends into the shell 902 and extends to the sample support position of the sample support device 800 to contact the measured object and perform testing. Further, in order to facilitate the observation of the measured object and the positions of the measured object and the probe, an observation window 904 can be arranged at the top of the shell 902, which can be heat-insulating glass. In addition, in order to further reduce the cold energy transmission between the sample support device 800 and the magnetic field generator 700 and avoid the mutual influence of the temperatures of the two, a heat-insulating cold shield 905 can be arranged between the sample support device 800 and the magnetic field generator 700. In addition, the shell 902, the supports 903 and other related structures are all fixed to a fixed table 906 for installation and use.

[0067] Please refer to Figure 10The present application also provides another probe station, which comprises a sample support device 800, a probe assembly 901, a first cold source, a second cold source, and a mechanical thermal switch. The first cold source is connected to the first secondary cold connection 200 through a cold chain 110, the second cold source is connected to the second secondary cold connection 300 through a cold chain 304, and the first cold source and the second cold source have different temperatures. When the temperature of the sample needs to be changed, the temperature of the sample is changed by changing the temperature of the sample support device 800. More specifically, when the temperature of the sample needs to be close to the temperature of the first cold source, the cold switch 400 is controlled to be in surface contact with the first secondary cold connection 200, thereby forming a cold path of the first cold source, the first secondary cold connection 200, the cold switch 400, and the sample support device 800. When the temperature of the sample needs to be close to the temperature of the second cold source, the cold switch 400 is controlled to be in surface contact with the second secondary cold connection 300, thereby forming a cold path of the second cold source, the second secondary cold connection 200, the cold switch 400, and the sample support device 800. Thus, the temperature of the sample support device 800 is switched without changing the temperature of the cold source, greatly shortening the cold path and improving the temperature change efficiency. In addition, the primary cold connection 100 can also be connected to the magnetic field generator 700 or the probe assembly 901 or other components that need to switch the temperature for rapid temperature control.

[0068] The basic principles, main features and advantages of the present application are shown and described above, and therefore the above description is only an embodiment of the present application. Those skilled in the art should understand that the present application is not limited by the above embodiment, and the above embodiment and description in the specification are only the principles of the present application. Without departing from the spirit and scope of the present application, various equivalent changes and improvements can be made, which will fall within the scope of the claimed present application.

Claims

1. A mechanical thermal switch, characterized in that: It includes a primary cooling connection section, a second-stage cooling connection section, a cooling switching section, and a control section. The first-stage and second-stage cooling connection sections are spaced apart, and the primary cooling connection section is coolingly connected to the cooling switching section. The control unit is configured to move the cooling switching unit, and the control unit controls the cooling switching unit to switch between the following states: First state: The cooling switching part is in surface contact with the first-stage cooling connection part, and there is a gap, line contact, or point contact between the cooling switching part and the second-stage cooling connection part, forming a cold energy transfer path of the primary cooling connection part, the cooling switching part, and the first-stage cooling connection part; Second state: There is no surface contact between the cooling switching part and the first-stage cooling connection part, and there is no surface contact between the cooling switching part and the second-stage cooling connection part. The cold energy transfer paths between the first-stage cooling connection part and the cooling switching part, and between the second-stage cooling connection part and the cooling switching part, are all disconnected. Third state: The cooling switching part is in surface contact with the second-stage cooling connection part, and there is a gap, line contact, or point contact between the cooling switching part and the first-stage cooling connection part, forming a cold energy transfer path of the primary cooling connection part, cooling switching part, and second-stage cooling connection part; as well as, The magnetic field generator is thermally connected to the first-stage cooling connection, the sample support device is thermally connected to the second-stage cooling connection, and the primary cooling connection is thermally connected to the cold source. or, The first cold source is thermally connected to the primary thermal conductive connection part, the second cold source is thermally connected to the secondary thermal conductive connection part, and the primary thermal conductive connection part is thermally connected to the component that needs to switch temperatures.

2. A mechanical thermal switch as described in claim 1, characterized in that: The mechanical thermal switch also includes an operating unit, which includes a push rod, a ball head, and a ball cup. The concave surface of the ball cup matches the convex surface of the ball head. The ball cup is connected to the control unit, and the ball head is drivenly connected to the push rod. The ball head and ball cup are configured to change between contact and separation states.

3. A mechanical thermal switch as described in claim 2, characterized in that: The operating part further includes a first elastic element, which pushes the ball cup away from the primary cooling connection part.

4. A mechanical thermal switch as described in claim 3, characterized in that: The operating part further includes a ball head seat and a second elastic element. The ball head is connected to the push rod via the ball head seat. The ball head seat and the ball head are connected to the upper limit in the direction of movement of the ball head. The second elastic element pushes the ball head away from the ball head seat.

5. A mechanical thermal switch as described in claim 4, characterized in that: The push rod is a screw rod, and the operating part also includes a first plate, a bearing, and a bearing seat. The push rod is threaded to the first plate, the push rod is connected to the bearing, the bearing seat is connected to the ball head seat, and the two end faces of the bearing are limited and fixed by the bearing seat and the ball head seat.

6. A mechanical thermal switch as described in claim 1, characterized in that: The cooling switching section is spindle-shaped, and a first contact surface and a second contact surface are respectively provided at both ends of the cooling switching section. The width of the cross-section of the first contact surface and the second contact surface gradually decreases from the middle of the cooling switching section to both ends.

7. A mechanical thermal switch as described in claim 1, characterized in that: The cooling switching part includes a first contact surface, a second contact surface, and a connecting frame that connects the first contact surface and the second contact surface. The first contact surface and the second contact surface are arranged opposite to each other and protrude from the connecting frame.

8. A mechanical thermal switch as described in any one of claims 6 or 7, characterized in that: The first-stage cooling connection part is provided with a first cooling surface that matches the first contact surface, and the second-stage cooling connection part is provided with a second cooling surface that matches the second contact surface; In the first state, the first cooling surface is in contact with the first contact surface; In the third state, the second cooling surface is in surface contact with the second contact surface.

9. A probe station, characterized in that: It includes a magnetic field generator, a sample support device, a probe assembly, a cold source, and a mechanical thermal switch as described in claim 1.

10. A probe station as described in claim 9, characterized in that: The cooling switching part is provided with a first contact surface and a second contact surface at both ends. The first-stage cooling connection part is provided with a first cooling surface that matches the first contact surface, and the second-stage cooling connection part is provided with a second cooling surface that matches the second contact surface. In the first state, the first cooling surface is in surface contact with the first contact surface. In the third state, the second cooling surface is in surface contact with the second contact surface.

11. A probe station, characterized in that: It includes a sample support device, a probe assembly, a first cold source, a second cold source, and a mechanical thermal switch as described in claim 1, wherein the primary heat-conducting connection is heat-conductingly connected to the sample support device.

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