Superconducting magnet low-temperature device

Abstract

The utility model relates to the technical field of superconducting magnets, in particular to a superconducting magnet low-temperature device which comprises a main framework and an outer cylinder arranged on the outer side of the main framework, and two end plates which are arranged at intervals and have L-shaped cross sections are arranged between the main framework and the outer cylinder. A main coil is arranged on the outer side of the main framework; an auxiliary framework of a cylindrical structure is arranged between the two end plates and located between the main framework and the outer cylinder. A service tower is fixed to the upper end of the outer barrel, a first opening penetrating up and down is formed in the position, corresponding to the service tower, of the outer barrel, and a heater is arranged on the outer barrel and located in the service tower. A plurality of through holes are formed in the positions, corresponding to the service towers, of the outer cylinder. According to the superconducting magnet low-temperature device, the heater is arranged on the upper portion of the superconducting magnet low-temperature device to heat the interior of the cavity, it is guaranteed that the pressure value in the cavity is in a relatively stable micro-positive pressure, and helium bubbles are effectively prevented from moving disorderly and being adsorbed to the main framework or the auxiliary framework, and then local heating of the magnet is caused; the device has the advantages of simple structure, convenience in manufacture, convenience in assembly and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of superconducting magnets, in particular to a superconducting magnet cryogenic device. Background Art

[0002] The stable operation of the magnetic resonance superconducting magnet must ensure that the superconducting magnet coil is immersed in an ultra-low temperature environment of liquid helium. Liquid helium is an expensive resource. Therefore, the liquid helium of the magnetic resonance superconducting magnet is required to achieve zero volatility. A refrigerator must be used to cool the cryogenic cavity of the superconducting magnet to condense the volatilized helium in the cryogenic cavity into liquid helium. When the magnetic resonance superconducting magnet is in operation, the pressure value in the cryogenic cavity of the superconducting magnet is required to be at a relatively stable micro-positive pressure. In the prior art, due to the continuous operation of the refrigerator, negative pressure occurs in the cryogenic container, and the outside air takes the opportunity to enter the cryogenic container and form ice in the cryogenic container, affecting the stable operation of the magnetic resonance superconducting magnet.

[0003] The prior art superconducting magnet cryogenic device includes a cylindrical cryogenic container, wherein a through inner hole is provided in the middle of the cryogenic container. The cryogenic container includes an inner cylinder and an outer cylinder which are sheathed together, and also includes two annular end plates arranged at two ends. A cryogenic coil is installed inside the cryogenic container. The cryogenic coil has the disadvantage of high manufacturing cost. Utility Model Content

[0004] The technical problem that the utility model intends to solve is to provide a superconducting magnet low-temperature device in view of the above shortcomings. By arranging a heater to heat the cavity, liquid helium absorbs heat to produce helium, thereby ensuring that the pressure value in the cavity is at a relatively stable micro-positive pressure, and the helium produced by the liquid helium absorbing heat directly floats upward to the gas layer in the cavity, effectively preventing helium bubbles from running around and being adsorbed on the main frame or the sub-frame. The utility model has the advantages of simple structure, convenient manufacture, and easy assembly.

[0005] To solve the above problems, the technical solution adopted by the utility model is as follows:

[0006] A superconducting magnet cryogenic device comprises an outer cylinder, a service tower is fixed on the upper end of the outer cylinder, a first opening penetrating from top to bottom is arranged on the outer cylinder corresponding to the service tower, and a heater is arranged on the outer cylinder and located inside the service tower.

[0007] As an improvement, a plurality of through holes are provided on the outer cylinder at positions corresponding to the service towers.

[0008] As an improvement, the outer cylinder is provided with a box body with a first opening at the upper end, and the heater is fixedly installed in the box body.

[0009] As an improvement, it also includes a cylindrical main frame, the outer cylinder is arranged on the outside of the main frame, and two end plates with an L-shaped cross-section are arranged between the main frame and the outer cylinder; a main coil is arranged on the outside of the main frame; a sub-frame with a cylindrical structure is arranged between the two end plates, and the sub-frame is located between the main frame and the outer cylinder.

[0010] As an improvement, the surface layer of the main skeleton is provided with a plurality of winding grooves arranged in parallel, each of which is wound with a first coil, and the plurality of first coils constitute the main coil.

[0011] As an improvement, the surface layer of the sub-frame is provided with two shielding coil grooves which are arranged at intervals, and shielding coils are arranged in both shielding coil grooves.

[0012] As an improvement, circular steps are provided on the inner sides of the two end plates, the outer diameter of the steps is matched with the inner diameter of the auxiliary frame, and both ends of the auxiliary frame are mounted on the steps.

[0013] As an improvement, the upper and lower parts of the sub-frame are both provided with a penetrating second opening, and the spaces inside and outside the sub-frame are connected through the second opening.

[0014] The utility model adopts the above technical solution, and has the following advantages compared with the prior art:

[0015] The superconducting magnet low-temperature device of the utility model heats the cavity by arranging a heater, and liquid helium absorbs heat to generate helium, thereby ensuring that the pressure value in the cavity is at a relatively stable micro-positive pressure, and the helium generated by the liquid helium absorbing heat directly floats upward to the gas layer in the cavity, effectively preventing helium bubbles from running around and being adsorbed on the main frame 1 or the sub-frame 5, thereby causing local heating of the magnet; it has the advantages of simple structure, convenient manufacture, and easy assembly.

[0016] The utility model is described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the structure of a superconducting magnet cryogenic device of the utility model;

[0018] Figure 2 for Figure 1 A top view of

[0019] Figure 3 for Figure 1 Schematic diagram of the structure of the middle and outer cylinders;

[0020] Among them: 1-main frame, 2-winding groove, 3-main coil, 4-end plate, 5-auxiliary frame, 6-outer cylinder, 7-service tower, 8-first opening, 9-heater, 10-through hole, 11-box body, 12-shielding coil, 13-step, 14-second opening. DETAILED DESCRIPTION

[0021] For the purpose of illustration and not limitation, Figure 1 The directions corresponding to the upper, lower, left and right ends of the superconducting magnet cryogenic device are defined as up, down, left and right; the side close to the center of the superconducting magnet cryogenic device is defined as inside, and the opposite side is defined as outside.

[0022] Example

[0023] like Figure 1 , Figure 2 and Figure 3 As shown together, a superconducting magnet cryogenic device comprises an outer cylinder 6 and a cylindrical main frame 1. The outer cylinder 6 is arranged on the outside of the main frame 1, and two end plates 4 with L-shaped cross sections are arranged between the main frame 1 and the outer cylinder 6; a main coil 3 is arranged on the outside of the main frame 1. A sub-frame 5 with a cylindrical structure is arranged between the two end plates 4, and the sub-frame 5 is located between the main frame 1 and the outer cylinder 6.

[0024] like Figure 1 , Figure 2 and Figure 3 As shown together, the surface layer of the main skeleton 1 is provided with a plurality of winding grooves 2 arranged in parallel, and the winding grooves 2 are all wound with first coils, and the plurality of first coils constitute the main coil 3. Preferably in this embodiment, the surface layer of the skeleton 1 is provided with six winding grooves 2 arranged in parallel, and the six winding grooves 2 are all wound with first coils, and the six first coils constitute the main coil 3. The surface layer of the secondary skeleton 5 is provided with two shielding coil grooves arranged at intervals, and shielding coils 12 are provided in the two shielding coil grooves.

[0025] like Figure 1 , Figure 2 and Figure 3 As shown together, the inner sides of the two end plates 4 are both provided with circular steps 13, the outer diameter of the steps 13 is adapted to the inner diameter of the sub-frame 5, and both ends of the sub-frame 5 are mounted on the steps 13. The upper and lower parts of the sub-frame 5 are both provided with penetrating second openings 14, and the spaces inside and outside the sub-frame 5 are connected through the second openings 14.

[0026] like Figure 1 , Figure 2 and Figure 3 As shown together, a service tower 7 is fixed to the upper end of the outer cylinder 6, and a first opening 8 is provided on the outer cylinder 6 corresponding to the position of the service tower 7, and a heater 9 is provided on the outer cylinder 6, and the heater 9 is located inside the service tower 7. A plurality of through holes 10 are provided on the outer cylinder 6 corresponding to the position of the service tower 7. The plurality of through holes 10 are respectively located on both sides of the first opening 8. A semi-enclosed box body 11 with an upper end opening is provided on the outer cylinder 6, and the heater 9 is fixedly installed in the box body 11.

[0027] The superconducting magnet cryogenic device of the utility model comprises a main frame 1, two end plates 4, and an outer cylinder 6 which form a cryogenic container with an upper end opening. When assembling the cryogenic container, first, the main frame 1 with the main coil 3 wound thereon and the sub-frame 5 with the shielding coil 12 wound thereon are sheathed together, and the sub-frame 5 is sheathed on the outside of the main frame 1. Then, two end plates 4 are installed between the sub-frame 5 and the main frame 1. The end plates 4 are fixedly connected to the main frame 1 by welding. Then, the outer cylinder 6 is installed on the outside of the end plates 4, and the end plates 4 are fixedly connected to the outer cylinder 6 by welding.

[0028] Then, the box body 11 and the heater 9 are fixedly installed on the outer cylinder 6. Finally, the box body 11 is fixedly installed on the outer cylinder 6.

[0029] When the superconducting magnet cryogenic device is in use, the chamber where the cold head of the magnetic resonance superconducting magnet is located is connected to the internal chamber of the service tower 7, and then connected to the chamber outside the main frame 1 through the first opening 8 and the second opening 14 on the secondary frame 5. The interior of the superconducting magnet cryogenic device is cooled by a refrigerator. In the prior art, a device for detecting the internal pressure of the superconducting magnet cryogenic device by the refrigerator is provided on the magnetic resonance superconducting magnet. For magnetic resonance superconducting magnets of different specifications and working conditions, the liquid level of liquid helium will be lower than the box body 11 during use, and may also submerge the box body 11.

[0030] When it is detected that the internal pressure is lower than the set micro-positive pressure, the heater 9 will be turned on to heat the inside of the superconducting magnet cryogenic device. When the heater 9 is above the liquid helium level, the heater 9 heats the helium above the liquid helium, so that the liquid helium absorbs heat and turns into helium, thereby increasing the pressure inside the superconducting magnet cryogenic device. When the heater 9 is below the liquid helium level, the heater 9 directly heats the liquid helium, and the liquid helium absorbs heat and turns into helium bubbles. The helium bubbles will rise along the box body 11 and enter the gas layer above the liquid helium through the upper opening of the box body 11, thereby increasing the pressure inside the superconducting magnet cryogenic device. The box body 11 has a guiding effect on the helium bubbles, which can effectively prevent the helium bubbles from being adsorbed to the local part of the magnet, resulting in a significant reduction in the contact area between the coil and the liquid helium, causing the local temperature to be too high and the coil to be unstable, thereby causing the risk of the magnetic resonance superconducting magnet losing its superconducting state.

[0031] When the internal pressure value of the superconducting magnet cryogenic device reaches the set value, the heater 9 stops heating.

[0032] When the refrigerator is working, some liquid helium will gather on the cold head of the refrigerator, and the liquid helium will drip into the superconducting magnet cryogenic device in response to the gathering of liquid helium. In the utility model, a plurality of through holes 10 are provided on the outer cylinder 6, and the liquid helium will first drip on the outer cylinder 6, and slide along the outer wall of the outer cylinder 6, and when passing through the through holes 10, it will enter the outer cylinder 6 through the through holes 10, and slide down along the inner wall of the outer cylinder 6 and slowly fall into the liquid helium. This structural design can effectively prevent the liquid helium on the cold head of the refrigerator from directly dripping into the liquid helium below, causing a greater impact on the liquid helium, causing a local temperature increase, and inducing the risk of magnet quenching.

[0033] In summary, the utility model is a superconducting magnet low-temperature device, which heats the cavity by arranging a heater 9, and the liquid helium absorbs heat to produce helium, thereby ensuring that the pressure value in the cavity is at a relatively stable micro-positive pressure, and the helium produced by the liquid helium absorbing heat directly floats upward to the gas layer in the cavity, effectively preventing helium bubbles from running around and being adsorbed on the main frame 1 or the sub-frame 5, thereby causing local heating of the magnet; it has the advantages of simple structure, easy manufacture, and easy assembly.

[0034] Finally, it should be noted that the above description is only a preferred embodiment of the utility model and is not intended to limit the utility model. Although the utility model is described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions recorded in the above embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A superconducting magnet cryogenic device, characterized in that: The invention comprises an outer cylinder (6), a service tower (7) being fixed at the upper end of the outer cylinder (6), a first opening (8) penetrating from top to bottom being provided at a position on the outer cylinder (6) corresponding to the service tower (7), a heater (9) being provided on the outer cylinder (6), and the heater (9) being located inside the service tower (7).

2. The superconducting magnet cryogenic device according to claim 1, characterized in that: A plurality of through holes (10) are provided on the outer cylinder (6) at positions corresponding to the service tower (7).

3. The superconducting magnet cryogenic device according to claim 1, characterized in that: The outer cylinder (6) is provided with a box body (11) having a first opening at an upper end, and the heater (9) is fixedly installed in the box body (11).

4. The superconducting magnet cryogenic device according to any one of claims 1 to 3, characterized in that: It also comprises a cylindrical main frame (1), the outer cylinder (6) being arranged on the outside of the main frame (1), and two end plates (4) being arranged at intervals and having an L-shaped cross section being arranged between the main frame (1) and the outer cylinder (6); a main coil (3) being arranged on the outside of the main frame (1); and a sub-frame (5) having a cylindrical structure being arranged between the two end plates (4), and the sub-frame (5) being located between the main frame (1) and the outer cylinder (6).

5. The superconducting magnet cryogenic device according to claim 4, characterized in that: The surface layer of the main frame (1) is provided with a plurality of winding grooves (2) arranged in parallel, each of the winding grooves (2) being wound with a first coil, and the plurality of first coils constitute the main coil (3).

6. The superconducting magnet cryogenic device according to claim 4, characterized in that: The surface layer of the secondary frame (5) is provided with two shielding coil slots arranged at intervals, and shielding coils (12) are provided in both shielding coil slots.

7. The superconducting magnet cryogenic device according to claim 4, characterized in that: A circular step (13) is provided on the inner side of each of the two end plates (4); the outer diameter of the step (13) matches the inner diameter of the auxiliary frame (5); and both ends of the auxiliary frame (5) are mounted on the step (13).

8. The superconducting magnet cryogenic device according to claim 7, characterized in that: The upper and lower parts of the sub-frame (5) are both provided with a penetrating second opening (14), and the spaces inside and outside the sub-frame (5) are connected via the second opening (14).

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