Lead structure for superconducting wire in vacuum cavity
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GEWU ZHIHAN (SUZHOU) SCI INSTR CO LTD
- Filing Date
- 2025-09-03
- Publication Date
- 2026-07-21
Smart Images
Figure CN224536759U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of superconducting technology, and in particular to a lead structure for superconducting wires in a vacuum cavity. Background Technology
[0002] Superconducting current leads are used to effectively connect conventional current (current transmitted through ordinary conductors at room temperature) with superconducting current (current transmitted through superconductors at low temperatures). In the vacuum chamber of a high magnetic field scanning tunneling microscope (STM), existing superconducting current leads are used for heat exchange against a heat sink outside the cryogenic Dewar. One end is connected to room temperature electrical feed, and the other end supplies power to the magnet through the superconducting wire. Under high current, the heat generated by the contact resistance and wire resistance cannot be absorbed and dissipated by the heat sink in time, which can easily cause the superconducting wire to lose quench, leading to quench loss and damage to the magnet. At the same time, because the heat sink is exposed outside the cryogenic Dewar, heat loss is relatively large, resulting in relatively poor overall heat exchange efficiency and stability. Utility Model Content
[0003] The purpose of this invention is to provide a lead structure for superconducting wires in a vacuum cavity, which can achieve rapid dissipation of heat from contact resistance and wire resistance, increase the operating time of the magnet in open loop, reduce the probability of magnet quenching, and extend the service life of the magnet; and the overall heat exchange effect and heat exchange stability are relatively good.
[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows:
[0005] A lead structure for a superconducting wire in a vacuum cavity includes a first Dewar disposed in the vacuum cavity and used to hold a first liquid refrigerant, a lead wire passing through the first Dewar, and an insulating and heat-conducting sleeve fitted over the lead wire. The two ends of the lead wire pass through the first Dewar, and the lead wire is immersed in the first liquid refrigerant through the insulating and heat-conducting sleeve.
[0006] The lead wire structure also includes two sets of sealing mechanisms respectively located between the end of the lead wire extending out of the first Dewar and the corresponding outer end face of the first Dewar. The sealing mechanism includes an insulating sleeve sleeved on the end of the lead wire and located outside the first Dewar, and a sealing flange for sealing the connection between the insulating sleeve and the corresponding outer end face of the first Dewar.
[0007] One end of the lead wire is used to connect to a regular wire located in the vacuum cavity, and the other end of the lead wire is used to connect to a superconducting wire located in the vacuum cavity.
[0008] Preferably, the two ends of the insulating heat-conducting sleeve extend out of the first Dewar and are respectively located in the two sets of sealing flanges.
[0009] More preferably, the two ends of the insulating heat-conducting sleeve are respectively used to abut against the two sets of insulating sleeves fitted at both ends of the lead wire.
[0010] Preferably, the sealing flange includes an inner flange ring whose inner end face abuts against the outer end face of the first Dewar, and an outer flange ring whose inner end face abuts against the outer end face of the inner flange ring.
[0011] More preferably, the sealing flange further includes a sealing ring sleeved on the outside of the lead wire and located between the inner flange ring and the outer flange ring.
[0012] More preferably, at least one of the outer end face of the inner flange ring and the inner end face of the outer flange ring is provided with a first mounting groove for inserting the sealing ring.
[0013] More preferably, the outer end face of the first Dewar is provided with a second mounting groove for inserting the inner flange ring, the depth of the second mounting groove being less than the thickness of the inner flange ring.
[0014] More preferably, the lead includes two rigid wires at both ends and a flexible wire for connecting the two rigid wires, with the two rigid wires extending outward from the corresponding end faces of the first Dewar.
[0015] More preferably, the inner flange ring is welded to the outer end face of the first Dewar, and the rigid wire, the corresponding insulating sleeve, and the outer flange ring form an integrated electrical feedthrough structure.
[0016] Preferably, there are at least two leads, which are run parallel to each other through the first Dewar.
[0017] Due to the application of the above technical solution, this utility model has the following advantages compared with the prior art: The lead wire structure of this utility model for superconducting wires in a vacuum cavity has the following advantages:
[0018] After the lead wire is fitted with an insulating heat-conducting sleeve and immersed in the first liquid refrigerant of the first Dewar, it can achieve rapid dissipation of heat from its contact resistance and wire resistance, increase the operating time of the magnet under open-loop conditions, reduce the probability of the superconducting wire and magnet losing quench, and extend the service life of the magnet.
[0019] After the lead wire is fitted with an insulating and heat-conducting sleeve, it is immersed in the first liquid refrigerant of the first Dewar. Sealing mechanisms are set at both ends of the lead wire that exit the first Dewar to prevent the cold energy in the first liquid refrigerant from dissipating into the vacuum chamber. The overall heat exchange effect and heat exchange stability are relatively good. Attached Figure Description
[0020] Appendix Figure 1This is a schematic diagram of the lead wire structure being installed in a vacuum cavity according to a specific embodiment of the present invention;
[0021] Appendix Figure 2 This is a schematic diagram of the first Dewar structure;
[0022] Appendix Figure 3 For the appendix Figure 2 Schematic diagram of the cross-sectional structure along line AA;
[0023] Appendix Figure 4 For the appendix Figure 3 Enlarged structural diagram at point B;
[0024] Appendix Figure 5 This is a schematic diagram of the connection structure between rigid and flexible wires.
[0025] The components include: 1. Vacuum chamber; 2. First Dewar; 21. Second mounting groove; 3. First liquid refrigerant; 4. Lead wire; 41. Rigid wire; 42. Flexible wire; 5. Insulating and heat-conducting sleeve; 6. Sealing mechanism; 61. Insulating sleeve; 62. Sealing flange; 621. Inner flange ring; 622. Outer flange ring; 623. Sealing ring; 63. First mounting groove; 7. Ordinary wire;
[0026] 8. Superconducting wire; 9. Second Dewar; 10. Second liquid refrigerant; 11. Magnet; 12. Room temperature electrical feedthrough. Detailed Implementation
[0027] The technical solution of this utility model will be further described below with reference to specific embodiments and accompanying drawings.
[0028] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the present invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.
[0029] In the description of the embodiments of this utility model, it should be understood that the terms "length", "inner", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the embodiments of this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the embodiments of this utility model.
[0030] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.
[0031] In this embodiment of the invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this embodiment of the invention according to the specific circumstances.
[0032] In this embodiment of the invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0033] The following disclosure provides many different implementations or examples for different structures of the embodiments of the present invention. To simplify the disclosure of the embodiments of the present invention, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the embodiments of the present invention. Furthermore, reference numerals and / or reference letters may be repeated in different examples of the embodiments of the present invention; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various implementations and / or arrangements discussed.
[0034] See Figure 1-3 As shown, this embodiment provides a lead structure for a superconducting wire in a vacuum cavity, including a first Dewar 2 disposed in a vacuum cavity 1 for holding a first liquid refrigerant 3, a lead wire 4 passing through the first Dewar 2, and an insulating heat-conducting sleeve 5 sleeved on the lead wire 4. The two ends of the lead wire 4 pass through the first Dewar 2 respectively, and the lead wire 4 is immersed in the first liquid refrigerant 3 through the insulating heat-conducting sleeve 5 and can exchange heat with the first liquid refrigerant 3.
[0035] In this embodiment, the upper end of the lead wire 4 is used to connect to the ordinary wire 7 located in the vacuum chamber 1, and the other end of the lead wire 4 is used to connect to the superconducting wire 8 located in the vacuum chamber 1. The ordinary wire 7 is connected to the room temperature electrical feed 12 located outside the vacuum chamber 1. The vacuum chamber 1 is also provided with a second Dewar 9 for holding the second liquid refrigerant 10, and the superconducting wire 8 abuts against the outside of the second Dewar 9, allowing heat exchange between the two. The other end of the superconducting wire 8 is used to connect to the magnet 11, which can be a dry structure or a wet structure.
[0036] The temperature of the superconducting wire 8 can be a low temperature of 4-5K or a high temperature of 77K. In this embodiment, the superconducting wire 8 is a high temperature superconducting wire with a temperature of 77K.
[0037] In this embodiment, the first liquid refrigerant 3 is liquid nitrogen, and the second liquid refrigerant 10 is liquid helium; the lead wire 4 is made of copper. In other embodiments, the lead wire 4 may be made of silver or other conductive materials.
[0038] See Figure 3 As shown, the lead structure for the superconducting wire in the vacuum chamber also includes two sets of sealing mechanisms 6. The sealing mechanisms 6 are located between the end of the lead wire 4 extending out of the first Dewar 2 and the corresponding outer end face of the first Dewar 2. Specifically, one set of sealing mechanisms 6 is located between the upper end of the lead wire 4 extending upwards from the first Dewar 2 and the upper end face of the first Dewar 2, and another set of sealing mechanisms 6 is located between the lower end of the lead wire 4 extending downwards from the first Dewar 2 and the lower end face of the first Dewar 2. Both sets of sealing mechanisms 6 are made of heat-insulating material, which not only ensures airtightness but also further prevents cold loss.
[0039] See Figure 4 As shown, the sealing mechanism 6 includes an insulating sleeve 61 fitted onto the end of the lead wire 4 and located outside the first Dewar 2, and a sealing flange 62 for sealing the corresponding outer end faces of the insulating sleeve 61 and the first Dewar 2. The sealing flange 62 includes an inner flange ring 621 whose inner end face abuts against the outer end face of the first Dewar 2, and an outer flange ring 622 whose inner end face abuts against the outer end face of the inner flange ring 621.
[0040] In this embodiment, the sealing flange 62 also includes a sealing ring 623 sleeved on the outside of the lead wire 4 and located between the inner flange ring 621 and the outer flange ring 622. The sealing ring 623 is sleeved on the outside of the insulating sleeve 61 to further increase the airtightness and prevent the loss of cold energy.
[0041] In this embodiment, at least one of the outer end face of the inner flange ring 621 and the inner end face of the outer flange ring 622 is provided with a first mounting groove 63 for inserting the sealing ring 623; the outer end face of the first Dewar 2 is provided with a second mounting groove 21 for inserting the inner flange ring 621, the depth of the second mounting groove 21 is less than the thickness of the inner flange ring 621, and the inner flange ring 621 is welded in the second mounting groove 21.
[0042] See Figure 4 As shown, the two ends of the insulating heat-conducting sleeve 5 extend out of the first Dewar 2 and are located in the two sets of sealing flanges 62 respectively. This structure increases the heat exchange area of the insulating heat-conducting sleeve 5 and the lead wire 4, and improves the heat exchange efficiency.
[0043] In this embodiment, the two ends of the insulating heat-conducting sleeve 5 are respectively used to abut against the two sets of insulating sleeves 61 fitted at both ends of the lead wire 4, so as to prevent the insulating heat-conducting sleeve 5 from shifting during operation, thereby avoiding affecting the heat exchange efficiency.
[0044] See Figure 5 As shown, the lead 4 includes two rigid wires 41 at both ends and a flexible wire 42 for electrically connecting the two rigid wires 41. The two rigid wires 41 extend outward from the corresponding end faces of the first Dewar 2.
[0045] In this embodiment, the inner flange ring 621 is welded to the outer end face of the first Dewar 2. The rigid wire 41, the corresponding insulating sleeve 61 and the outer flange ring 622 form an integrated electrical feedthrough structure, which facilitates the assembly and disassembly of the whole unit.
[0046] In this embodiment, there are two leads 4, which are threaded parallel to each other through the first Dewar 2. In other embodiments, there may be multiple leads 4.
[0047] The above embodiments are only for illustrating the technical concept and features of this utility model, and are intended to enable those skilled in the art to understand the content of this utility model and implement it accordingly. They should not be construed as limiting the scope of protection of this utility model. All equivalent changes or modifications made in accordance with the spirit and essence of this utility model should be included within the scope of protection of this utility model.
Claims
1. A lead structure for superconducting wires in a vacuum cavity, characterized in that: It includes a first Dewar disposed in a vacuum chamber for holding a first liquid refrigerant, a lead wire passing through the first Dewar, and an insulating heat-conducting sleeve fitted over the lead wire. The two ends of the lead wire pass through the first Dewar, and the lead wire is immersed in the first liquid refrigerant through the insulating heat-conducting sleeve. The lead wire structure also includes two sets of sealing mechanisms respectively located between the end of the lead wire extending out of the first Dewar and the corresponding outer end face of the first Dewar. The sealing mechanism includes an insulating sleeve sleeved on the end of the lead wire and located outside the first Dewar, and a sealing flange for sealing the connection between the insulating sleeve and the corresponding outer end face of the first Dewar. One end of the lead wire is used to connect to a regular wire located in the vacuum cavity, and the other end of the lead wire is used to connect to a superconducting wire located in the vacuum cavity.
2. The lead structure for superconducting wires in a vacuum cavity according to claim 1, characterized in that: The two ends of the insulating heat-conducting sleeve extend out of the first Dewar and are located in the two sets of sealing flanges respectively.
3. The lead structure for superconducting wires in a vacuum cavity according to claim 2, characterized in that: The two ends of the insulating heat-conducting sleeve are respectively used to abut against the two sets of insulating sleeves fitted at both ends of the lead wire.
4. The lead structure for superconducting wires in a vacuum cavity according to claim 1, characterized in that: The sealing flange includes an inner flange ring whose inner end face abuts against the outer end face of the first Dewar, and an outer flange ring whose inner end face abuts against the outer end face of the inner flange ring.
5. The lead structure for superconducting wires in a vacuum cavity according to claim 4, characterized in that: The sealing flange also includes a sealing ring sleeved on the outside of the lead wire and located between the inner flange ring and the outer flange ring.
6. The lead structure for superconducting wires in a vacuum cavity according to claim 5, characterized in that: At least one of the outer end face of the inner flange ring and the inner end face of the outer flange ring is provided with a first mounting groove for inserting the sealing ring.
7. The lead structure for superconducting wires in a vacuum cavity according to claim 4, characterized in that: The outer end face of the first Dewar is provided with a second mounting groove for inserting the inner flange ring, and the depth of the second mounting groove is less than the thickness of the inner flange ring.
8. The lead structure for superconducting wires in a vacuum cavity according to claim 4, characterized in that: The lead includes two rigid wires at both ends and a flexible wire for connecting the two rigid wires, with the two rigid wires extending outward from the corresponding end faces of the first Dewar.
9. The lead structure for superconducting wires in a vacuum cavity according to claim 8, characterized in that: The inner flange ring is welded to the outer end face of the first Dewar, and the hard wire, the corresponding insulating sleeve and the outer flange ring form an integrated electrical feedthrough structure.
10. The lead structure for superconducting wires in a vacuum cavity according to claim 1, characterized in that: There are at least two leads, which are run parallel to each other through the first Dewar.