Device for checking and treating blockage of needle valve in liquid helium Dewar

Abstract

The invention provides a needle valve blockage checking and processing device in a liquid helium Dewar, and relates to the technical field of needle valve blockage detection. The needle valve blockage checking and processing device comprises an adapter and a transparent pipe, the adapter comprises a plurality of KF ports, the transparent pipe is in through connection with one of the KF ports of the adapter, and one or more functional modules of an imaging module, a temperature measuring assembly and a heating assembly are arranged in the transparent pipe. And the function modules are in one-to-one correspondence with and electrically connected with the adapter interfaces matched with the function modules in the rest KF ports. The needle valve blockage checking and processing device is simple in structure, can quickly and accurately determine the reason of needle valve blockage, and can perform timely dredging treatment according to different reasons.

Description

Technical Field

[0001] The invention relates to the technical field of needle valve blockage detection, and in particular to a needle valve blockage detection and processing device in a liquid helium dewar. Background Art

[0002] The sample chamber of a liquid helium dewar is generally used to place superconducting materials (such as FeSeTe, etc.) to measure magnetoresistance, Hall, magnetization, etc., or to place multiferroic materials (such as Fe2Mo3O8, CuO, etc.) to measure dielectric, magnetization, magnetostriction, etc. The temperature range in the sample chamber of a liquid helium dewar is 1.6K-300K, and the cooling method is helium gas flow decompression refrigeration, that is, liquid helium flows from the liquid helium chamber through the needle valve into the sample chamber, the pump pumps the sample chamber to a negative pressure, and the liquid helium evaporates into a helium gas flow and is pumped away by the pump to cool the sample chamber. The needle valve can control the flow rate of liquid helium entering the sample chamber, and controlling the needle valve can control the cooling rate in the sample chamber. Since liquid helium is expensive and helium itself is a non-renewable resource, the pump will be connected to an external pipeline to recycle the helium and liquefy it into liquid helium for recycling.

[0003] During use, the needle valve may be blocked for a variety of reasons: 1) Oxygen, nitrogen, water vapor, etc. in the air that enters the sample chamber due to misoperation will turn into solid at low temperatures and block the needle valve; 2) Solid debris that accidentally falls into the liquid helium chamber when replenishing liquid helium may also block the needle valve; 3) During the production and transportation process, hydrogen mixed in the liquid helium will also turn into solid in the liquid helium, causing the needle valve to be blocked.

[0004] There are many reasons for needle valve blockage, which need to be gradually investigated. However, the time of water-cooled magnet machine is precious. If the needle valve blockage is not handled in time, or it takes a long time to investigate the cause of the blockage, it will have a great impact. However, in the prior art, there is no simple and efficient method and corresponding device for checking and promptly dealing with the cause of needle valve blockage in liquid helium dewar. Summary of the invention

[0005] 1. Technical issues to be resolved In view of the shortcomings of the prior art, the present invention provides a device for checking and treating the blockage of a needle valve in a liquid helium dewar, which solves the problem that the prior art cannot simply and quickly check and treat the blockage of a needle valve in a liquid helium dewar.

[0006] (II) Technical solution To achieve the above objectives, the present invention is implemented through the following technical solutions: A device for checking and treating the blockage of a needle valve in a liquid helium dewar, the device comprising: an adapter and a transparent tube; Wherein, the adapter includes a plurality of KF ports, and the transparent tube is connected through one of the plurality of KF ports of the adapter; The transparent tube includes one or more functional modules including an imaging module, a temperature measurement component, and a heating component; the one or more functional modules correspond one-to-one with the adapters adapted to the one or more functional modules provided in the remaining KF ports, and are electrically connected.

[0007] In one embodiment, the connection between the KF port and the transparent tube is sealed.

[0008] Preferably, the number of the KF ports is 4.

[0009] In one embodiment, the adapter includes a six-pin Ramer connector, and the six-pin Ramer connector is electrically connected to the temperature measuring component, the heating component, and the temperature controller respectively.

[0010] In one embodiment, the temperature measurement component includes a thermometer, the heating component includes a heating wire, and the imaging module includes an endoscope and a light source.

[0011] In a preferred embodiment, the periphery of the endoscope is wrapped with a layer of copper foil, and the copper foil is fixed to the inner wall of the transparent tube through a bracket; The heating wire is wound around the outside of the copper foil and close to the bottom of the transparent tube; The thermometer is arranged on the inner wall of the copper foil.

[0012] In one embodiment, an anti-reflective component is provided at the bottom of the transparent tube, and the anti-reflective component is used to prevent specular reflection of light.

[0013] In a preferred embodiment, the anti-reflective component is a slope integrally formed with the transparent tube at the bottom port of the transparent tube.

[0014] In another embodiment, the anti-reflective component is a polarizing plate, and the polarizing plate is installed outside the lens of the imaging module.

[0015] In one embodiment, the transparent tube includes but is not limited to a transparent quartz tube.

[0016] In one embodiment, the sealing process includes but is not limited to sealant sealing process, rubber sealing process, flange sealing process, etc.

[0017] (III) Beneficial effects The present invention provides a device for checking and treating the blockage of a needle valve in a liquid helium dewar. Compared with the prior art, the device has the following beneficial effects: The needle valve blockage inspection and treatment device comprises: an adapter and a transparent tube, wherein the adapter comprises a plurality of KF ports, and the transparent tube is connected to one of the plurality of KF ports of the adapter, and the transparent tube comprises: one or more functional modules of an imaging module, a temperature measuring component, and a heating component, and the functional modules correspond to the adapter ports in the remaining KF ports that are adapted to the functional modules one by one and are electrically connected. The needle valve blockage inspection and treatment device has a simple structure, and can quickly and accurately determine the cause of the needle valve blockage, and can promptly clear the blockage according to different causes. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a three-dimensional diagram of a device for checking and treating a needle valve blockage in a liquid helium dewar in an embodiment of the present application; Figure 2 It is a structural schematic diagram of a device for checking and treating a needle valve blockage in a liquid helium dewar from another perspective in an embodiment of the present application; Figure 3 A cross-sectional view of an adapter in an embodiment of the present application; Figure 4 A cross-sectional view of a transparent tube in an embodiment of the present application; In the figure: 1- adapter; 2-transparent tube; 3-imaging module; 4-temperature measurement component; 5-heating component; 6-copper foil. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] Dewar is an insulated container that can isolate the external heat from the cryogenic liquid inside. The needle valve is a structure inside the Dewar, located at the bottom of the liquid helium chamber in the Dewar, used to control the speed at which the liquid helium in the liquid helium chamber flows into the sample chamber.

[0022] The sample chamber of the liquid helium dewar is generally used to place superconducting materials (such as FeSeTe, etc.) to measure magnetoresistance, Hall, magnetization, etc., or to place multiferroic materials (such as Fe2Mo3O8, CuO, etc.) to measure dielectric, magnetization, magnetostriction, etc. The temperature range of the sample chamber in the liquid helium dewar is 1.6K-300K, and the cooling method is helium gas flow decompression refrigeration. The liquid helium in the liquid helium chamber is infused from the outside through the infusion port, and the liquid helium flows from the liquid helium chamber through the needle valve into the sample chamber. The pump pumps the sample chamber to negative pressure, and the liquid helium evaporates into helium gas flow and is pumped away by the pump to cool the sample chamber. The setting of the needle valve can control the flow rate of liquid helium into the sample chamber, and controlling the needle valve can control the cooling rate in the sample chamber.

[0023] Since liquid helium is expensive and helium itself is a non-renewable resource, the pump will be connected to an external pipeline to recycle the helium gas and liquefy it into liquid helium for recycling.

[0024] During use, the needle valve may be blocked for a variety of reasons: 1) Operational errors during sample placement may cause air to enter the sample chamber, and at low temperatures, oxygen, nitrogen, water vapor, etc. in the air will turn into solids, which may block the needle valve; 2) When replenishing liquid helium in the liquid helium chamber, some solid debris from the outside may accidentally fall into the liquid helium chamber, and as the liquid helium flows, it may also block the needle valve; 3) During the production and transportation process, hydrogen may be mixed in the liquid helium, and hydrogen will also turn into solids in the liquid helium, causing the needle valve to be blocked.

[0025] It can be seen that there are many reasons for the blockage of the needle valve in the liquid helium dewar, which need to be gradually checked and dredged in a targeted manner. However, the time of the water-cooled magnet machine is precious. If the needle valve blockage is not handled in time, or it takes a long time to check the cause of the blockage, it will cause a great impact. At present, there is no simple and efficient method and corresponding device for checking and handling the cause of the needle valve blockage in the liquid helium dewar.

[0026] Based on this, the embodiment of the present application provides a device for checking and processing the blockage of the needle valve in the liquid helium dewar, thereby solving the problem that the prior art cannot simply and quickly check and process the blockage of the needle valve in the liquid helium dewar, and achieves the purpose of quickly and accurately determining the cause of the needle valve blockage and taking targeted measures.

[0027] The technical solution in the embodiment of the present application is to solve the above technical problems, and the overall idea is as follows: In order to simply and quickly check the cause of the needle valve blockage in the liquid helium dewar and carry out timely unblocking treatment in a targeted manner, the present application uses an adapter to connect the transparent tube, and sets one or more functional modules such as an imaging module, a temperature measurement component, and a heating component in the transparent tube, and uses wires to connect the above-mentioned functional modules to external instruments through the adapter interface set in the KF port of the adapter, so as to achieve temperature measurement, temperature control, and image acquisition inside the transparent tube, thereby achieving rapid troubleshooting and targeted and efficient treatment of the cause of the needle valve blockage in the liquid helium dewar.

[0028] In order to better understand the above technical solution, the above technical solution will be described in detail below with reference to the drawings in the specification, the structure of each component in the drawings, the connection relationship between the components, and the specific implementation methods.

[0029] It should be noted that the device for checking and treating the blockage of the needle valve in the liquid helium dewar proposed in the embodiment of the present application is inserted into the liquid helium cavity through the infusion port, and the quality of the liquid helium inside the liquid helium cavity can be observed. Moreover, the device proposed in the embodiment of the present application is only used when the needle valve is blocked, and it does not occupy the infusion port at ordinary times, and does not affect the replenishment of liquid helium.

[0030] See also Figure 1-Figure 3 The present embodiment provides a device for checking and treating a needle valve blockage in a liquid helium dewar, comprising: The adapter 1 and the transparent tube 2. The adapter 1 includes a plurality of KF ports, and the transparent tube 2 is connected to one of the plurality of KF ports of the adapter 1.

[0031] The transparent tube 2 includes but is not limited to one or more functional modules of the imaging module 3, the temperature measuring component 4, and the heating component 5. Among them, one or more functional modules of the imaging module 3, the temperature measuring component 4, and the heating component 5 are electrically connected to the adapters provided in the remaining KF ports, respectively, and the adapters are adapted in quantity and function to the data acquisition functions of one or more functional modules of the imaging module 3, the temperature measuring component 4, and the heating component 5. In specific implementation, the adapters are embedded in the remaining KF ports.

[0032] In one embodiment, see Figure 1-Figure 3 The number of KF ports in the adapter 1 is 4, of which two KF ports extending along the axial direction of the transparent tube 2 are connected, and one (bottom) KF port is connected to one end of the transparent tube 2. The other (top) KF port is connected to a pump to facilitate vacuuming the inside of the sample chamber.

[0033] Preferably, the connection between the KF port and the transparent tube 2 is sealed. It should be noted that the sealing method between the transparent tube 2 and one of the KF ports of the adapter 1 includes but is not limited to sealing by sealant, and can also be other equivalent replacement sealing solutions. For example, rubber sealing, flange sealing and other sealing methods.

[0034] In one embodiment, the two KF ports on the side of the adapter 1, one KF port is used to connect a six-pin Ramo connector, which is electrically connected to the temperature measuring component 4 and the heating component 5 through a wire inwardly, and is electrically connected to an external temperature controller outwardly, and the temperature controller can set the heating power and observe the internal temperature in real time. The other KF port is electrically connected to the imaging module 3, and is used to collect data from the imaging module 3 for imaging. It should be noted that in a specific implementation, the six-pin Ramo connector can also be replaced by other vacuum connectors that can achieve corresponding functions.

[0035] In a preferred embodiment, the temperature measuring component 4 is a thermometer, the heating component 5 is a heating wire, and the imaging module 3 includes an endoscope and a light source.

[0036] like Figure 4 , which is a cross-sectional view of the internal structure of the transparent tube 2. Figure 4 The endoscope is arranged in the middle of the entire transparent tube 2 along the axis position and direction of the transparent tube 2, and the endoscope has its own light source, which can provide illumination in the liquid helium cavity for easy observation.

[0037] In addition, in a preferred embodiment, the periphery of the endoscope is wrapped with a layer of copper foil 6, and the copper foil 6 is fixed to the inner wall of the transparent tube 2 by a bracket (not shown in the figure). A heating wire is wound around the outer side of the copper foil 6 near the bottom of the transparent tube 2, and at this position, a thermometer is attached between the copper foil 6 and the endoscope and on the inner wall of the copper foil 6. It should be noted that the setting of the copper foil 6 can ensure uniform heating and ensure that the endoscope is at the working temperature, and the copper foil 6 is fixed to the transparent tube 2 by a bracket, and the bracket can avoid direct contact between the copper foil 6 and the transparent tube 2 to cause heat transfer.

[0038] In addition, since the endoscope cannot work properly at low temperatures, the KF port and pump on the top are used to evacuate the inside of the transparent tube 2 (vacuum cannot conduct heat), and then the power of the heating wire is controlled to put the endoscope in normal working condition. When only liquid helium needs to be observed, the power of the heating wire does not need to be too high, which can avoid transferring too much heat to the liquid helium, causing the liquid helium to boil and affect observation, and also avoid the liquid helium causing the temperature inside the transparent tube 2 to be too low, causing the endoscope to stop working. When the liquid helium needs to be evaporated, it only needs to adjust the internal vacuum and the power of the heating wire to evaporate the liquid helium.

[0039] In a preferred embodiment, an anti-reflective component is provided at the bottom of the transparent tube 2, and the anti-reflective component can prevent the light from forming a mirror reflection and affecting the endoscope imaging.

[0040] In a preferred embodiment, the anti-reflective component is an inclined surface integrally formed with the bottom of the transparent tube 2, such as Figure 4As shown, the setting of the inclined plane can avoid the influence of the specular reflection of light on the endoscope imaging. In another preferred embodiment, the anti-reflective component is a polarizing plate, and the polarizing plate is installed outside the endoscope lens to avoid reflection, thereby avoiding the influence on the endoscope imaging.

[0041] In one embodiment, the transparent tube 2 is a transparent quartz tube. It should be noted that the transparent quartz tube is a special industrial technical glass made of silicon dioxide, which has a series of excellent physical and chemical properties such as transparency, poor thermal conductivity, firmness, high temperature resistance, corrosion resistance, good thermal stability, good light transmission, and good electrical insulation. It should be further noted that in a specific implementation, the transparent tube 2 can also be other materials that can meet the requirements of transparency, poor thermal conductivity, and sufficient firmness.

[0042] The use method and principle of a device for checking and treating needle valve blockage in a liquid helium dewar proposed in the above embodiments of the present application: First, using the device for inspecting and treating the needle valve blockage in the liquid helium dewar proposed in the above embodiment of the present application, the device can be inserted into the liquid helium cavity through the liquid helium infusion port to directly observe the amount of impurities in the liquid helium and the state of the needle valve opening, and then determine the cause of the needle valve blockage.

[0043] If there are too many solid impurities in the liquid helium, adjust the internal vacuum and the power of the heating wire to evaporate the liquid helium in the liquid helium chamber, and perform purification treatment when filling the liquid helium next time; If the blockage is caused by external debris entering the liquid helium chamber, the Dewar needs to be completely warmed up and the debris inside the Dewar needs to be cleaned; if no obvious problem is observed, it may be that during the sample change process, improper operation has caused air to enter the sample chamber, resulting in blockage of the liquid helium outlet at the bottom of the sample chamber. At this time, there is no need to fully heat up the Dewar, only adjust the power of the internal heating wire and briefly heat it up to melt and evaporate the fixed nitrogen.

[0044] In summary, compared with the prior art, the present invention has the following beneficial effects: 1. The present application proposes a device for checking and treating the blockage of a needle valve in a liquid helium dewar, which comprises: an adapter and a transparent tube, wherein the adapter comprises a plurality of KF ports, and the transparent tube is connected to one of the KF ports of the adapter, and the transparent tube comprises: one or more functional modules of an imaging module, a temperature measuring component, and a heating component, and the functional module corresponds to and is electrically connected to the adapter ports in the remaining KF ports that are adapted to the functional modules. The device for checking and treating the blockage of the needle valve has a simple structure, and can quickly and accurately determine the cause of the blockage of the needle valve, and can promptly dredge the blockage for different reasons. Specifically, the time of the water-cooled magnet machine is precious. If the blockage of the needle valve is not handled in time, it takes several days to wait for the internal temperature to rise naturally. The device for checking and treating the blockage of the needle valve of the present application can evaporate the liquid helium in the liquid helium chamber within half an hour, and the needle valve can be warmed up and unblocked in 4 hours. At the same time, the quality of the liquid helium can be observed, and the liquid helium with impurities inside can be replaced in time to avoid the problem of the needle valve being blocked repeatedly.

[0045] 2. The present application proposes a device for checking and treating the blockage of a needle valve in a liquid helium dewar, wherein an anti-reflective component is provided at the bottom of the transparent tube, and the anti-reflective component can prevent the mirror reflection of light from affecting the imaging of the endoscope.

[0046] 3. The present application proposes a device for checking and treating the blockage of a needle valve in a liquid helium dewar. A layer of copper foil is wrapped around the periphery of the endoscope. The copper foil is fixed to the inner wall of a transparent tube by a bracket, thereby avoiding direct contact between the copper foil and the transparent tube to cause heat transfer.

[0047] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "including one..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0048] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for checking and treating the blockage of a needle valve in a liquid helium dewar, characterized in that: The device comprises: an adapter (1) and a transparent tube (2); The adapter (1) comprises a plurality of KF ports, and the transparent tube (2) is connected to one of the plurality of KF ports of the adapter (1); The transparent tube (2) includes one or more functional modules including an imaging module (3), a temperature measurement component (4), and a heating component (5); the one or more functional modules correspond one to one with adapters adapted to the one or more functional modules provided in the remaining KF ports, and are electrically connected.

2. The device according to claim 1, characterized in that The connection between the KF port and the transparent tube (2) is sealed.

3. The device according to claim 1, characterized in that The adapter comprises a six-pin Ramo connector, and the six-pin Ramo connector is electrically connected to the temperature measuring component (4), the heating component (5), and the temperature controller respectively.

4. The device according to claim 1, characterized in that The temperature measurement component (4) comprises a thermometer, the heating component (5) comprises a heating wire, and the imaging module (3) comprises an endoscope and a light source.

5. The device according to claim 4, characterized in that The periphery of the endoscope is wrapped with a layer of copper foil (6), and the copper foil (6) is fixed to the inner wall of the transparent tube (2) via a bracket; The heating wire is wound around the outside of the copper foil (6) and is close to the bottom of the transparent tube (2); The thermometer is arranged on the inner wall of the copper foil (6).

6. The device according to claim 1, characterized in that An anti-reflective component is provided at the bottom of the transparent tube (2), and the anti-reflective component is used to prevent specular reflection of light.

7. The device according to claim 6, characterized in that The anti-reflective component is a sloped surface integrally formed with the transparent tube (2) at the bottom port of the transparent tube (2).

8. The device according to claim 6, characterized in that The anti-reflective component is a polarizing plate, and the polarizing plate is installed outside the lens of the imaging module (3).

9. The device according to any one of claims 1 to 8, characterized in that: The transparent tube (2) comprises a transparent quartz tube.

10. The device according to claim 2, characterized in that The sealing process includes a sealant sealing process.

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