Magnet safety make-up helium device

Abstract

The application discloses a magnet safety helium supplement device and relates to the technical field of low-temperature superconductivity. The device comprises an operating cylinder, a helium supplement pipe, a plug assembly, a heating box, at least one gas guide pipe, a gas flow control mechanism, a linkage mechanism and a gas flow guide cover. The operating cylinder is installed on a magnet Dewar cover plate. When the plug assembly is separated from the helium supplement pipe, the linkage mechanism triggers the gas flow control mechanism to conduct the gas guide pipe, so that the low-temperature helium gas in the operating cylinder, which is caused by the positive pressure of the helium cavity, enters the heating box through the gas guide pipe. After being heated by the heating element, the hot helium gas enters the gas flow guide cover which is arranged outside the operating cylinder through the gas outlet of the heating box, thereby forming a hot helium gas curtain which flows upwards along the outer wall of the operating cylinder. The hot helium gas curtain forms a warm and positive pressure protection environment around the helium supplement port, effectively isolates the external humid air and fundamentally eliminates the possibility that water vapor condenses into ice at the helium supplement port, thereby ensuring the continuous and normal performance of the helium supplement work.

Description

Technical Field

[0001] This invention relates to the field of low-temperature superconductivity technology, and in particular to a safe helium replenishment device for magnets. Background Technology

[0002] A typical liquid helium-cooled superconducting magnet system includes a helium chamber, a cooling shield, and an external Dewar flare. The superconducting coil is immersed in liquid helium within the helium chamber. Before magnet installation and excitation testing, and after excitation testing, or when liquid helium needs to be added due to daily wear and tear, liquid helium must be added to the helium chamber through an external helium inlet and helium inlet tube until the superconducting magnet is completely submerged. Because the helium inlet tube is generally quite long, it must be fully inserted under the cover plate during operation.

[0003] However, in actual helium replenishment operations, the liquid helium inside the helium chamber maintains a positive pressure due to continuous evaporation. Once the plug on the helium replenishment port is opened, cryogenic helium gas will continuously spray out. This continuous spray of cryogenic helium gas causes a large amount of water vapor in the surrounding air to condense, and it may even enter the port and accumulate as ice on the inner wall of the pipe. Since a single helium replenishment operation typically lasts for more than half a day, the condensation and icing phenomena will intensify, easily causing the inside of the helium replenishment port to become blocked by ice, severely affecting the normal progress of helium replenishment and posing a threat to equipment safety. At the same time, the resulting low-temperature environment also poses a safety hazard to the operators. Summary of the Invention

[0004] This invention provides a safe helium replenishment device for magnets, which can solve the problem in the prior art where the continuous ejection of low-temperature helium gas causes a large amount of water vapor in the air around the helium replenishment port to condense, and even enter the helium replenishment port and accumulate ice on the inner wall of the pipe, which seriously affects the normal operation of helium replenishment.

[0005] A safe helium replenishment device for a magnet includes an operating cylinder, a helium replenishment tube, a plug assembly, a heating box, at least one gas delivery tube, an airflow control mechanism, a linkage mechanism, and an airflow guide shroud. The operating cylinder is mounted on a magnet Dewar cover plate. The helium replenishment tube is disposed inside the operating cylinder for replenishing liquid helium into the helium chamber. The plug assembly is disposed at the upper end of the helium replenishment tube. The heating box is disposed outside the operating cylinder and contains a heating element. At least one gas delivery tube connects the interior of the operating cylinder to the heating box. The airflow control mechanism is connected to the gas delivery tube and controls the opening and closing of the gas delivery tube. One end of the linkage mechanism is connected to the plug assembly, and the other end is connected to the airflow control mechanism, such that when the plug assembly is disengaged from the helium replenishment tube, the gas delivery tube is opened, and vice versa. The airflow guide shroud is sleeved outside the operating cylinder and located below the heating box, communicating with the outlet of the heating box, and guides the heated helium gas discharged from the outlet into an upward-flowing gas curtain along the outer wall of the operating cylinder.

[0006] The present invention provides a magnetic safety helium replenishment device, which, compared with the prior art, has, but is not limited to, the following beneficial effects: This magnet-based safe helium replenishment device employs a linkage mechanism and an airflow control mechanism. When the plug assembly detaches from the helium replenishment tube, the linkage mechanism triggers the airflow control mechanism to open the gas duct. This allows the low-temperature helium gas, which surges out of the operating cylinder due to the positive pressure in the helium chamber, to enter the heating box through the gas duct. After being heated by the heating element, the hot helium gas enters the airflow guide hood surrounding the operating cylinder from the outlet of the heating box. This forms a hot helium gas curtain that flows upward along the outer wall of the operating cylinder. This hot helium gas curtain creates a warm and positive-pressure protective environment around the helium replenishment port, effectively isolating external humid air and fundamentally eliminating the possibility of water vapor condensing into ice at the helium replenishment port. This ensures the continuous and normal operation of helium replenishment and creates a safe operating microenvironment with a suitable temperature and no risk of icing for the operator, guaranteeing the continuity and safety of long-term helium replenishment operations.

[0007] Furthermore, the airflow control mechanism includes a rotating disk and a transmission assembly. The rotating disk is rotatably disposed inside the air guide pipe. One end of the transmission assembly is connected to the rotating disk, and the other end of the transmission assembly is connected to the linkage mechanism.

[0008] Furthermore, the linkage mechanism includes a reaction plate, and an elastic reset member connected to an operating cylinder is provided at the bottom of the reaction plate. The elastic reset member is used to drive the reaction plate to float upward. The reaction plate is circumferentially connected to a rotating disk through a transmission assembly. A lifting sleeve is provided at the top of the reaction plate. The lifting sleeve is sleeved on the helium replenishment tube. An adjusting bolt threadedly connected to the helium replenishment tube is provided at the top of the lifting sleeve.

[0009] Furthermore, the transmission assembly includes a screw and a drive sleeve. The lower end of the screw is connected to the rotating disk, and the drive sleeve is fixed on the reaction plate and sleeved on the screw. The inner wall of the drive sleeve is provided with a helical groove that helically engages with the screw.

[0010] Furthermore, an annular rotating gas box is rotatably connected to the outlet of the heating box. Multiple inclined discharge holes with the same inclination direction are provided through the inner wall of the rotating gas box, so that the reaction force generated when the heated helium gas is ejected through the inclined discharge holes can drive the rotating gas box to rotate, forming a rotating upward airflow.

[0011] Furthermore, the rotating air box is sleeved on the outside of the airflow guide hood, and a sliding sealing structure is provided between the inner wall of the rotating air box and the outer wall of the airflow guide hood.

[0012] Furthermore, the outer wall of the airflow guide shroud is provided with a plurality of guide vanes in the circumferential direction. The guide vanes extend along the axial direction of the operating cylinder to guide the airflow upward and form an air curtain.

[0013] Furthermore, the helium replenishment tube includes a long tube and a short tube, both of which are mounted on the operating cylinder, and both the long tube and the short tube are equipped with plug assemblies.

[0014] Furthermore, the plug assembly includes a plug body, a long rod is provided at the bottom of the plug body, and multiple cryogenic baffles are provided axially on the long rod to prevent cryogenic helium gas from being directly ejected along the inner wall of the helium replenishment tube.

[0015] Furthermore, the heating element is an electric heating wire, a heating rod, or a heating film. Attached Figure Description

[0016] Figure 1 A schematic diagram of the structure of a magnet safety helium replenishment device according to an embodiment of the present invention; Figure 2 A schematic diagram of the installation of a magnet safety helium replenishment device according to an embodiment of the present invention; Figure 3 A cross-sectional view of a magnet safety helium replenishment device according to an embodiment of the present invention; Figure 4 for Figure 1 Schematic diagram of the central linkage mechanism; Figure 5 for Figure 1 A schematic diagram of the airflow control mechanism; Figure 6 for Figure 1 Schematic diagram of the rotating gas box structure; Figure 7 for Figure 1 A schematic diagram of the structure of the middle plug head assembly.

[0017] Explanation of reference numerals in the attached figures: 1. Operating cylinder; 2. Helium replenishment tube; 21. Long tube; 22. Short tube; 3. Plug assembly; 31. Plug body; 32. Long rod; 33. Cryogenic baffle; 4. Heating box; 41. Heating element; 5. Gas guide tube; 6. Airflow control mechanism; 61. Rotary disk; 62. Transmission assembly; 621. Screw; 622. Drive sleeve; 7. Linkage mechanism; 71. Reaction plate; 72. Elastic reset component; 73. Lifting sleeve; 74. Adjusting bolt; 8. Airflow guide hood; 81. Guide vane; 9. Rotating gas box; 91. Inclined discharge port; 10. Magnet Dewar cover plate; 11. Power supply box. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this application clearer, specific embodiments of this application are described clearly and completely below with reference to the accompanying drawings. It should be understood that the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments described in this application without creative effort will fall within the scope of protection of this application.

[0019] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the specification of this application is for the purpose of describing specific embodiments only and is not intended to limit this application; the terms "comprising," "including," "having," "containing," "comprise," etc., in the specification, claims, and accompanying drawings of this application are open-ended terms, indicating that a method comprises one or more steps, or an apparatus comprises one or more elements, but do not exclude the inclusion of other steps or elements. The terms "first," "second," etc., in the specification, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or primary / secondary relationship. 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 with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0020] In the description of this application, it should be understood that the terms "upper," "lower," "left," "right," "front," "rear," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not 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 this application. It should also be noted that...

[0021] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0022] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0023] like Figure 1-3 As shown in the figure, an embodiment of the present invention provides a magnetic safety helium replenishment device, including an operating cylinder 1, a helium replenishment tube 2, a stopper assembly 3, a heating box 4, at least one gas guide tube 5, an airflow control mechanism 6, a linkage mechanism 7, and an airflow guide shroud 8. The operating cylinder 1 is mounted on a magnetic Dewar cover plate 10; the helium replenishment tube 2 is disposed inside the operating cylinder 1 for replenishing liquid helium into the helium chamber; the stopper assembly 3 is disposed at the upper end of the helium replenishment tube 2; the heating box 4 is disposed outside the operating cylinder 1 and contains a heating element 41; at least one gas guide tube 5 connects to... The operating cylinder 1 is connected to the heating box 4; the airflow control mechanism 6 is connected to the gas guide pipe 5 to control the opening and closing of the gas guide pipe 5; one end of the linkage mechanism 7 is connected to the plug assembly 3 and the other end is connected to the airflow control mechanism 6, so that when the plug assembly 3 is disengaged from the helium replenishment pipe 2, the gas guide pipe 5 is triggered to open, and vice versa; the airflow guide shroud 8 is sleeved on the outside of the operating cylinder 1 and located below the heating box 4, and is connected to the gas outlet of the heating box 4, and is used to guide the heated helium gas discharged from the gas outlet into an air curtain that flows upward along the outer wall of the operating cylinder 1.

[0024] In this embodiment, by setting up a linkage mechanism 7 and an airflow control mechanism 6, when the plug assembly 3 is disengaged from the helium replenishment tube 2, the linkage mechanism 7 triggers the airflow control mechanism 6 to open the air duct 5, so that the low-temperature helium gas that surges out of the operating cylinder 1 due to the positive pressure of the helium chamber enters the heating box 4 through the air duct 5. After being heated by the heating element 41, the hot helium gas enters the airflow guide shroud 8 sleeved on the outside of the operating cylinder 1 from the outlet of the heating box 4, forming a hot helium gas curtain that flows upward along the outer wall of the operating cylinder 1. This hot helium gas curtain forms a warm and positive pressure protective environment around the helium replenishment port, effectively isolating the external humid air and fundamentally eliminating the possibility of water vapor condensing into ice at the helium replenishment port, thus ensuring the continuous and normal operation of the helium replenishment work.

[0025] Specifically, by overturning the conventional thinking of completely sealing off cryogenic helium to prevent cold leakage in traditional helium replenishment operations, this method cleverly utilizes the continuous positive pressure environment inevitably created by the evaporation of liquid helium inside the helium chamber. Instead of blocking, it guides and collects the originally disorderly gushing cryogenic helium flow, which could cause icing hazards, through the pathway formed by the operating cylinder 1, the gas guide pipe 5, and the airflow control mechanism 6, utilizing the existing positive pressure helium. This guided cryogenic helium then enters the heating box 4, where it is heated to a safe temperature on-site by the heating element 41, instantly transforming the source of cold damage that causes water vapor condensation into a dry and warm protective resource. This process transforms the energy form from harmful to beneficial. Finally, the heated helium gas is transported to the airflow guide hood 8. With its specific sleeve and guiding structure, a ring-shaped hot gas barrier that rises evenly along the outer wall of the operating cylinder 1 is precisely constructed around the helium replenishment port, thus creating a protective air curtain. This air curtain uses dry, inert hot helium gas as a medium to isolate the intrusion path of external humid air from the source, preventing water vapor from condensing and freezing on the helium replenishment port and the inner wall of the pipe. At the same time, it creates a safe operating microenvironment with a suitable temperature and no risk of freezing for the operators, ensuring the continuity and safety of long-term helium replenishment operations.

[0026] like Figure 4 and Figure 5 As shown, the airflow control mechanism 6 includes a rotating disk 61 and a transmission assembly 62. The rotating disk 61 is rotatably disposed inside the air guide pipe 5. One end of the transmission assembly 62 is connected to the rotating disk 61, and the other end of the transmission assembly 62 is connected to the linkage mechanism 7.

[0027] In this embodiment, when the plug assembly 3 is pulled out of the helium replenishment tube 2, the linear motion generated by the linkage mechanism 7 can be precisely converted into the rotational opening action of the rotating disk 61 in the gas guide tube 5 through the transmission assembly 62, thereby switching the gas guide tube 5 from a closed state to a conductive state, realizing the mechanical synchronous linkage of helium replenishment operation and protective gas flow start-up, without the need for additional electrical control or manual intervention. The structure is compact and the operation is reliable. Moreover, the rotational opening and closing method of the rotating disk 61 can realize the precise control and effective sealing of the gas guide tube 5, ensuring that the cryogenic helium gas only enters the heating box 4 for heating when needed, avoiding the waste of cold energy and safety hazards caused by disorderly leakage of helium gas.

[0028] like Figure 4 and Figure 5 As shown, the linkage mechanism 7 includes a reaction plate 71. The bottom of the reaction plate 71 is provided with an elastic reset member 72 connected to the operating cylinder 1. The elastic reset member 72 is used to drive the reaction plate 71 to float upward. The reaction plate 71 is circumferentially connected to the rotating disk 61 through the transmission assembly 62. The top of the reaction plate 71 is provided with a lifting sleeve 73, which is sleeved on the helium replenishment tube 2. The top of the lifting sleeve 73 is provided with an adjusting bolt 74 that is threadedly connected to the helium replenishment tube 2.

[0029] In this embodiment, when the operator loosens and pulls out the adjusting bolt 74 to open the plug assembly 3, the adjusting bolt 74 simultaneously lifts the reaction plate 71 upward through the lifting sleeve 73. At the same time, the elastic reset member 72 provides an auxiliary upward thrust to ensure that the reaction plate 71 responds sensitively and is stably maintained in the upward position. The upward linear motion of the reaction plate 71 is converted into the rotational motion of the rotating disk 61 through the transmission component 62, thereby automatically opening the gas duct 5 at the same time as the plug assembly 3 is pulled out. Conversely, after helium replenishment is completed, tightening the adjusting bolt 74 will press down the reaction plate 71 to reset and close the gas duct 5. This realizes a purely mechanical instantaneous linkage between helium replenishment operation and the opening and closing of the protective gas flow. The entire linkage mechanism 7 is compact in structure and reliable in operation, requiring no electrical control or additional operation steps. Moreover, the threaded connection between the adjusting bolt 74 and the helium replenishment tube 2 can not only achieve reliable sealing of the plug assembly 3, but also provide precise control of the up and down movement stroke of the reaction plate 71.

[0030] like Figure 4 and Figure 5 As shown, the transmission assembly 62 includes a screw 621 and a drive sleeve 622. The lower end of the screw 621 is connected to the rotating disk 61. The drive sleeve 622 is fixed on the reaction plate 71 and sleeved on the screw 621. The inner wall of the drive sleeve 622 is provided with a helical groove that helically engages with the screw 621.

[0031] In this embodiment, when the plug assembly 3 is pulled out and the reaction plate 71 floats upward under the drive of the elastic reset member 72, the reaction plate 71 drives the drive sleeve 622 to move upward synchronously. During the upward movement, the drive sleeve 622 applies a circumferential thrust to the screw 621 through the spiral groove on its inner wall, forcing the screw 621 to drive the rotating disk 61 to rotate precisely within the gas guide pipe 5. This smoothly and reliably converts the linear floating motion of the reaction plate 71 into the rotational opening action of the rotating disk 61. Conversely, after helium replenishment is completed, the reaction plate 71 moves downward, and the reverse spiral cooperation between the drive sleeve 622 and the screw 621 drives the rotating disk 61 to rotate in the opposite direction to close the gas guide pipe 5. This spiral transmission method has a compact structure and a short transmission path, and can achieve high torque and high precision motion conversion within the limited space of the operating cylinder 1. Moreover, the spiral self-locking characteristic between the spiral groove and the screw 621 can ensure that the rotating disk 61 can stably maintain its current position in both the open and closed states, avoiding accidental deflection of the rotating disk 61 due to vibration or airflow impact.

[0032] like Figure 3 and Figure 6 As shown, a ring-shaped rotating gas box 9 is rotatably connected to the outlet of the heating box 4. Multiple inclined discharge holes 91 with the same inclined direction are provided through the inner side wall of the rotating gas box 9, so that the reaction force generated when the heated helium gas is ejected through the inclined discharge holes 91 can drive the rotating gas box 9 to rotate, forming a rotating upward airflow.

[0033] In this embodiment, the heated helium gas, after being heated by the heating element 41, enters the rotating gas box 9 from the outlet of the heating box 4. When it is ejected outward from the inclined discharge hole 91, the reaction force generated by the airflow jet forms a continuous and consistent thrust component along the circumference of the rotating gas box 9 through the inclined discharge hole 91. Thus, the rotating gas box 9 can be automatically rotated relative to the heating box 4 without the need for external power. This allows the heated helium gas to be evenly distributed in the airflow guide shroud 8 in a rotating jet manner, thereby forming a uniform rotating upward airflow around the operating cylinder 1. Compared with the laminar airflow jetted in a single direction, this rotating upward airflow has a more comprehensive circumferential coverage and a more uniform flow velocity distribution, which can effectively eliminate airflow blind spots. This allows the heated helium gas curtain to be evenly wrapped around the helium replenishment port in a 360° omnidirectional manner, further improving the protective effect of isolating external humid air and preventing water vapor from condensing into ice. Moreover, the automatic rotation of the rotating gas box 9 relies entirely on the energy of the airflow itself, without the need for an additional motor or transmission device. The structure is simple, energy-efficient, and reliable in operation.

[0034] like Figure 1 and Figure 3 As shown, the rotating air box 9 is sleeved on the outside of the airflow guide hood 8, and a sliding sealing structure is provided between the inner wall of the rotating air box 9 and the outer wall of the airflow guide hood 8.

[0035] In this embodiment, when the rotating gas box 9 rotates stably relative to the airflow guide shroud 8 under the reaction force of the airflow ejected from the inclined discharge hole 91, the sliding sealing structure forms a reliable airtight barrier at the rotational mating surface between the two, effectively preventing the heated helium gas from leaking directly upward from the annular gap between the rotating gas box 9 and the airflow guide shroud 8. This forces all the heated helium gas to be ejected through the inclined discharge hole 91 and then collected by the airflow guide shroud 8 and guided into an annular air curtain flowing upward along the outer wall of the operating cylinder 1, thereby ensuring the integrity of the air curtain flow and the stability of the air curtain formation. At the same time, the sliding sealing structure provides a low-friction motion mating interface for the free rotation of the rotating gas box 9 while ensuring the sealing effect, enabling the rotating gas box 9 to respond sensitively to the airflow reaction force and rotate continuously and stably, thereby ensuring the uniform distribution of heated helium gas within a 360° circumferential range of the helium replenishment port.

[0036] Specifically, the sliding seal structure can be composed of an annular groove and an annular sliding plate.

[0037] like Figure 3 and Figure 6 As shown, multiple guide vanes 81 are arranged circumferentially on the outer wall of the airflow guide shroud 8. The guide vanes 81 extend along the axial direction of the operating cylinder 1 to guide the airflow upward and form an air curtain.

[0038] In this embodiment, by setting multiple guide vanes 81 extending axially along the outer wall of the airflow guide shroud 8, the hot helium gas ejected from the inclined discharge hole 91 of the rotating gas box 9 and collected by the airflow guide shroud 8 is forced to be rectified and guided by the guide vanes 81 as it flows upward along the outer wall of the operating cylinder 1. The helium gas flow, which may originally be in a rotating and diffused state, is divided into multiple independent gas streams that flow in an orderly manner along the axial direction by the guide vanes 81. This effectively suppresses the circumferential turbulence and radial diffusion of the airflow, and allows the hot helium gas to be pushed vertically upward along the outer wall of the operating cylinder 1 in a more concentrated direction and at a higher flow rate. As a result, a dense gas curtain with uniform thickness, complete coverage, and not easily blown away by the external transverse airflow is quickly formed around the helium replenishment port, which significantly improves the forming efficiency and continuous stability of the hot gas barrier.

[0039] like Figure 3 and Figure 4 As shown, the helium replenishment tube 2 includes a long tube 21 and a short tube 22. Both the long tube 21 and the short tube 22 are mounted on the operating cylinder 1, and both the long tube 21 and the short tube 22 are equipped with plug assemblies 3.

[0040] In this embodiment, by setting the helium replenishment tube 2 as a dual-tube structure of a long tube 21 and a short tube 22, and with both the long tube 21 and the short tube 22 mounted on the operating cylinder 1 and each equipped with an independent stopper assembly 3, the operator can flexibly select the helium replenishment channel according to the actual amount of liquid helium missing in the helium chamber: when the liquid helium loss is large and a large amount of rapid replenishment is required, the stopper assembly 3 on the long tube 21 is opened, and the deeper insertion depth of the lower end of the long tube 21 allows the liquid helium to be directly injected into the deep part of the helium chamber, avoiding splashing and evaporation loss caused by liquid helium dripping from too high a height; when the liquid helium loss is small and only a small amount of fine replenishment is required, the stopper assembly 3 on the short tube 22 is opened, and the shallower insertion depth of the short tube 22 facilitates precise control of the replenishment amount, preventing overfilling. At the same time, the amount of residual cryogenic helium in the short tube 22 is relatively small, and the gushing intensity is weaker when it is opened, further reducing the risk of local low temperature and water vapor condensation at the helium replenishment port. The dual-tube collaborative design significantly improves the safety and flexibility of the helium replenishment operation.

[0041] like Figure 3 and Figure 7 As shown, the plug assembly 3 includes a plug body 31, a long rod 32 is provided at the bottom of the plug body 31, and multiple cryogenic baffles 33 are provided axially upward on the long rod 32 to prevent cryogenic helium gas from being directly ejected along the inner wall of the helium replenishment pipe 2.

[0042] In this embodiment, by setting the plug assembly 3 as a combination of the plug body 31, the long rod 32, and multiple cryogenic baffles 33, when the plug assembly 3 is pulled away from the upper port of the helium replenishment tube 2 and the positive pressure in the helium cavity drives the cryogenic helium gas to surge upward along the helium replenishment tube 2, the cryogenic helium gas flow will inevitably collide with the multiple cryogenic baffles 33 distributed axially along the long rod 32 in the narrow channel on the inner wall of the helium replenishment tube 2. The cryogenic baffles 33 form a multi-stage blocking and turbulence effect on the high-speed surging cryogenic helium gas, breaking the concentrated jet that originally rushed directly out along the center or inner wall of the helium replenishment tube 2 into a dispersed turbulent flow, effectively reducing the ejection speed of cryogenic helium gas at the helium replenishment port and the concentration of cold energy per unit area. Thus, at the initial moment of opening the plug assembly 3, the cryogenic impact intensity in the helium replenishment port area is significantly weakened, and the rate of sudden condensation of water vapor in the surrounding air at the helium replenishment port is slowed down, which provides a critical buffer time for the subsequent linkage mechanism 7 to trigger the airflow control mechanism 6 to open the gas pipe 5 and establish a hot helium protective air curtain.

[0043] like Figure 1 and Figure 3 As shown, the heating element 41 is an electric heating wire, heating rod, or heating film, and the heating element 41 is connected to the power supply box 11.

[0044] In this embodiment, by setting the heating element 41 to various optional forms such as electric heating wire, heating rod, or heating film, and connecting the heating element 41 to the power supply box 11 to provide a stable power supply, the heating box 4 can flexibly select the most suitable type of heating element 41 according to the actual working conditions, power requirements, and space size. Electric heating wire is low in cost and easy to wind, heating rod has a large heat capacity and rapid heating, while heating film has the advantages of uniform surface heating and thin structure. Regardless of the form used, the low-temperature helium introduced from the gas guide pipe 5 can be heated efficiently, stably, and controllably under the continuous power supply of the power supply box 11, ensuring that the helium output to the rotating gas box 9 and the airflow guide hood 8 is always maintained at a suitable safe temperature, providing a stable and reliable heat source guarantee for the continuous generation of the hot helium protective gas curtain around the helium replenishment port.

[0045] The above-disclosed embodiments are merely a few specific examples of the present invention. However, the embodiments of the present invention are not limited thereto, and any variations that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A magnetic safety helium replenishment device, characterized in that, include: The operating cylinder (1) is installed on the magnet Dewar cover plate (10); A helium replenishment tube (2) is installed inside the operating cylinder (1) and is used to replenish liquid helium into the helium chamber; A plug assembly (3) is disposed at the upper port of the helium replenishment tube (2); Heating box (4) is located outside the operating cylinder (1) and has heating element (41) inside. At least one air guide tube (5) connects the inside of the operating cylinder (1) to the heating box (4); An airflow control mechanism (6) is connected to the air duct (5) and is used to control the opening and closing of the air duct (5); The linkage mechanism (7) is connected at one end to the plug assembly (3) and at the other end to the airflow control mechanism (6), so that when the plug assembly (3) is disconnected from the helium supply tube (2), the gas guide tube (5) is activated, and vice versa. An airflow guide hood (8) is fitted on the outside of the operating cylinder (1) and located below the heating box (4). It is connected to the air outlet of the heating box (4) and is used to guide the heated helium gas discharged from the air outlet into an air curtain that flows upward along the outer wall of the operating cylinder (1).

2. The magnet safety helium replenishment device as described in claim 1, characterized in that, The airflow control mechanism (6) includes a rotating disk (61) and a transmission assembly (62). The rotating disk (61) is rotatably disposed in the air guide pipe (5). One end of the transmission assembly (62) is connected to the rotating disk (61), and the other end of the transmission assembly (62) is connected to the linkage mechanism (7).

3. The magnet safety helium replenishment device as described in claim 2, characterized in that, The linkage mechanism (7) includes a reaction plate (71). The bottom of the reaction plate (71) is provided with an elastic reset member (72) connected to the operating cylinder (1). The elastic reset member (72) is used to drive the reaction plate (71) to float upward. The reaction plate (71) is circumferentially connected to the rotating disk (61) through the transmission assembly (62). The top of the reaction plate (71) is provided with a lifting sleeve (73). The lifting sleeve (73) is sleeved on the helium replenishment tube (2). The top of the lifting sleeve (73) is provided with an adjusting bolt (74) that is threadedly connected to the helium replenishment tube (2).

4. The magnet safety helium replenishment device as described in claim 3, characterized in that, The transmission assembly (62) includes a screw (621) and a drive sleeve (622). The lower end of the screw (621) is connected to the rotating disk (61). The drive sleeve (622) is fixed on the reaction plate (71) and sleeved on the screw (621). The inner wall of the drive sleeve (622) is provided with a spiral groove that is helically engaged with the screw (621).

5. The magnet safety helium replenishment device as described in claim 1, characterized in that, The outlet of the heating box (4) is rotatably connected to an annular rotating gas box (9). Multiple inclined discharge holes (91) with the same inclination direction are provided through the inner side wall of the rotating gas box (9), so that the reaction force generated when the heated helium gas is ejected through the inclined discharge holes (91) can drive the rotating gas box (9) to rotate, forming a rotating upward airflow.

6. The magnet safety helium replenishment device as described in claim 5, characterized in that, The rotating air box (9) is sleeved on the outside of the airflow guide hood (8), and a sliding sealing structure is provided between the inner wall of the rotating air box (9) and the outer wall of the airflow guide hood (8).

7. The magnet safety helium replenishment device as described in claim 1, characterized in that, The outer wall of the airflow guide hood (8) is provided with a plurality of guide vanes (81) in the circumferential direction. The guide vanes (81) extend along the axial direction of the operating cylinder (1) to guide the airflow upward and form an air curtain.

8. The magnet safety helium replenishment device as described in claim 1, characterized in that, The helium replenishment tube (2) includes a long tube (21) and a short tube (22), both of which are mounted on the operating cylinder (1), and both the long tube (21) and the short tube (22) are equipped with plug assemblies (3).

9. The magnet safety helium replenishment device as described in claim 1, characterized in that, The plug assembly (3) includes a plug body (31), a long rod (32) is provided at the bottom of the plug body (31), and multiple low-temperature baffles (33) are provided on the long rod (32) axially upward to prevent low-temperature helium gas from being directly ejected along the inner wall of the helium replenishment tube (2).

10. The magnet safety helium replenishment device as described in claim 1, characterized in that, The heating element (41) is an electric heating wire, a heating rod, or a heating film.

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