Vacuum system for compact high-magnetic field ion generators

Abstract

The present invention relates to the field of vacuum technology of radioactive medical equipment, and discloses a vacuum system for a compact strong magnetic field ion generating device, comprising: an ion generating device, a plurality of molecular pumps provided with magnetic field shielding covers, a plurality of cryopumps, a mechanical pump group, a Roots pump group, a plurality of pneumatic plug valves, a plurality of pneumatic baffle valves, a plurality of first resistance gauges, a plurality of second resistance gauges, and a vacuum control device, wherein the vacuum control device is respectively connected with the molecular pump, the cryopump, the mechanical pump group, the Roots pump group, the pneumatic plug valve, the pneumatic baffle valve, the first resistance gauge, and the second resistance gauge, and is used to control the molecular pump, the cryopump, the mechanical pump group, the Roots pump group, the pneumatic plug valve, and the pneumatic baffle valve according to the vacuum degree, so as to evacuate the ion generating device to a target vacuum degree. Thus, the vacuum system of the accelerator can be avoided from being polluted, a higher ultimate vacuum effect can be achieved by increasing the extraction capacity of water vapor and hydrogen, and the device can also be operated in a strong magnetic field environment.

Description

Technical Field

[0001] The invention relates to the field of vacuum technology for radioactive medical equipment, and in particular to a vacuum system for a compact strong magnetic field ion generating device. Background Art

[0002] At present, ion generators generally use diffusion pumps or molecular pumps as the main pumps. Diffusion pumps have high power consumption, are easy to pollute the accelerator vacuum, and are large in size, making them inconvenient to use in compact accelerators. Since compact ion generators cannot be baked to remove water vapor, the working gas is generally hydrogen, and the molecular pump has a poor pumping effect on water vapor and hydrogen, so using only a molecular pump as the main pump is not conducive to the extraction of extreme vacuum. The pneumatic plug valve and pneumatic baffle valve used are equipped with solenoid valves. The switch position signals of the pneumatic plug valve and pneumatic baffle valve generally use magnetic induction signals. In a strong magnetic field environment, the solenoid valve and magnetic induction signal will be interfered by the strong magnetic field. The rotating rotor generates eddy currents and heats up in a strong magnetic field environment, so it cannot be used in a strong magnetic field environment. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems in the related art to a certain extent. To this end, the first purpose of the present invention is to propose a vacuum system for a compact strong magnetic field ion generating device, integrating the solenoid valve in the solenoid valve box, so that the pneumatic plug valve and the pneumatic baffle valve used can be separated from the solenoid valve, and can be kept away from the strong magnetic field environment as a whole, effectively avoiding the influence of the strong magnetic field on the position signal, and the switch position signals of the pneumatic plug valve and the pneumatic baffle valve used use mechanical induction signals, which can effectively avoid the interference of the strong magnetic field on the position signal, and the molecular pump used is installed in the molecular pump magnetic field shielding cover, which effectively avoids the influence of the strong magnetic field on the molecular pump. It can also avoid polluting the vacuum system of the accelerator, and can achieve a higher ultimate vacuum effect by increasing the extraction capacity of water vapor and hydrogen, and can operate in a strong magnetic field environment.

[0004] To achieve the above-mentioned purpose, the first embodiment of the present invention proposes a vacuum system for a compact strong magnetic field ion generating device, including: an ion generating device; a plurality of molecular pumps and a plurality of cryogenic pumps provided with magnetic field shielding covers, respectively connected to the ion generating device, and all used to evacuate the ion generating device; a mechanical pump group, respectively connected to the molecular pump and the cryogenic pump through vacuum pipelines, used to serve as a pre-stage of the molecular pump and a regeneration pump of the cryogenic pump; a Roots pump group, respectively connected to the molecular pump and the cryogenic pump through vacuum pipelines, used to cooperate with the mechanical pump group to evacuate the ion generating device; a plurality of pneumatic plug valves, arranged between the ion generating device and the plurality of molecular pumps and the plurality of cryogenic pumps, used to control the plurality of molecular pumps and the plurality of cryogenic pumps to evacuate the ion generating device. a plurality of pneumatic baffle valves, respectively connected to the ion generating device and the vacuum pipeline, for controlling the on-off of the vacuum pipeline; a plurality of first resistance gauges, connected to the ion generating device, for detecting a first vacuum degree of the ion generating device; a plurality of second resistance gauges, respectively connected to the molecular pump and the cryogenic pump through the vacuum pipeline, for detecting a second vacuum degree of the vacuum pipeline; a vacuum control device, respectively connected to the molecular pump, the cryogenic pump, the mechanical pump group, the Roots pump group, the pneumatic gate valve, the pneumatic baffle valve, the first resistance gauge, and the second resistance gauge, for controlling the molecular pump, the cryogenic pump, the mechanical pump group, the Roots pump group, the pneumatic gate valve, and the pneumatic baffle valve according to the first vacuum degree and the second vacuum degree, so as to evacuate the ion generating device to a target vacuum degree.

[0005] In addition, the vacuum system for the compact high-magnetic-field ion generating device according to the above embodiment of the present invention may also have the following additional technical features:

[0006] According to some embodiments of the present invention, the molecular pump is arranged inside the magnetic field shielding cover; the magnetic field shielding cover includes a magnetic shielding neck tube, a magnetic shielding outer cylinder, and a magnetic shielding bottom plate, one end of the magnetic shielding neck tube is connected to the pump port of the molecular pump through a sealing ring and a sealing ring bracket, one end of the magnetic shielding outer cylinder is connected to the magnetic shielding neck tube, and the other end is connected to the magnetic shielding bottom plate.

[0007] According to some embodiments of the present invention, the magnetic field shielding cover also includes a sealing plate assembly, and the magnetic shielding outer cylinder is provided with a first opening and a second opening, the first opening is used to connect the cable of the molecular pump with the molecular pump in the magnetic field shielding cover, and the second opening is used to connect the vacuum pipeline with the molecular pump in the magnetic field shielding cover.

[0008] According to some embodiments of the present invention, the molecular pump includes a first molecular pump, a second molecular pump, a third molecular pump and a fourth molecular pump; the cryogenic pump includes a first cryogenic pump, a second cryogenic pump, a third cryogenic pump and a fourth cryogenic pump; the mechanical pump group includes a first mechanical pump and a second mechanical pump; the first mechanical pump is connected to the first molecular pump, the second molecular pump, the third molecular pump and the fourth molecular pump through a vacuum pipeline, and the second mechanical pump is connected to the first cryogenic pump, the second cryogenic pump, the third cryogenic pump and the fourth cryogenic pump through a vacuum pipeline; the Roots pump group includes a first Roots pump and a second Roots pump, one end of the first Roots pump is connected to the first mechanical pump through a vacuum pipeline, and the other end of the first Roots pump is connected to the first molecular pump, the second molecular pump, the third molecular pump through a vacuum pipeline. The pump is connected to the fourth molecular pump, one end of the second Roots pump is connected to the second mechanical pump through a vacuum pipeline, and the other end of the second Roots pump is connected to the first cryogenic pump, the second cryogenic pump, the third cryogenic pump and the fourth cryogenic pump through a vacuum pipeline; the first resistance gauge includes a first sub-resistance gauge and a second sub-resistance gauge, the first sub-resistance gauge is connected in parallel with the first cold cathode ionization gauge, and the second sub-resistance gauge is connected in parallel with the second cold cathode ionization gauge; the second resistance gauge includes a third sub-resistance gauge and a fourth sub-resistance gauge, the third sub-resistance gauge is arranged between the first Roots pump and the first molecular pump, the second molecular pump, the third molecular pump and the fourth molecular pump, and the fourth sub-resistance gauge is arranged between the second Roots pump and the first cryogenic pump, the second cryogenic pump, the third cryogenic pump and the fourth cryogenic pump; pneumatic The gate valves include a first gate valve, a second gate valve, a third gate valve, a fourth gate valve, a fifth gate valve, a sixth gate valve, a seventh gate valve, and an eighth gate valve; the first gate valve is arranged between the ion generating device and the first molecular pump, the second gate valve is arranged between the ion generating device and the second molecular pump, the third gate valve is arranged between the ion generating device and the first cryogenic pump, the fourth gate valve is arranged between the ion generating device and the second cryogenic pump, the fifth gate valve is arranged between the ion generating device and the third molecular pump, the sixth gate valve is arranged between the ion generating device and the fourth molecular pump, the seventh gate valve is arranged between the ion generating device and the third cryogenic pump, and the eighth gate valve is arranged between the ion generating device and the fourth cryogenic pump; the pneumatic The baffle valve includes a first baffle valve, a second baffle valve, a third baffle valve, a fourth baffle valve, a fifth baffle valve, a sixth baffle valve, a seventh baffle valve, and an eighth baffle valve. The first baffle valve is arranged between the first Roots pump and the third sub-resistance gauge, the second baffle valve is arranged between the second Roots pump and the fourth sub-resistance gauge, the third baffle valve is arranged between the third sub-resistance gauge and the fourth sub-resistance gauge, the fourth baffle valve is arranged between the third sub-resistance gauge and the ion generating device, the fifth baffle valve is arranged between the first cryogenic pump and the fourth sub-resistance gauge, the sixth baffle valve is arranged between the second cryogenic pump and the fourth sub-resistance gauge, the seventh baffle valve is arranged between the third cryogenic pump and the fourth sub-resistance gauge, and the eighth baffle valve is arranged between the fourth cryogenic pump and the fourth sub-resistance gauge.

[0009] According to some embodiments of the present invention, the vacuum system for the compact high magnetic field ion generator further includes a nitrogen source connected to the ion generator for filling the ion generator with nitrogen to break the vacuum of the ion generator.

[0010] According to some embodiments of the present invention, the pneumatic flapper valve further includes a ninth flapper valve and a tenth flapper valve, wherein the ninth flapper valve is disposed between the nitrogen source and the ion generator, and the tenth flapper valve is disposed between the ninth flapper valve and the ion generator.

[0011] According to some embodiments of the present invention, the above-mentioned vacuum system for the compact strong magnetic field ion generating device also includes a first compressor and a second compressor, the first compressor is connected to the first cryopump and the second cryopump, and the second compressor is connected to the third cryopump and the fourth cryopump.

[0012] According to some embodiments of the present invention, the vacuum control device is configured to control the regeneration of the cryopump, including: controlling the closing of the third gate valve, the fourth gate valve, the seventh gate valve, the eighth gate valve, the first compressor and the second compressor, and turning on the second mechanical pump and the second Roots pump; controlling the first cryopump, the second cryopump, the third cryopump and the fourth cryopump to turn on the heating mode, and when the first cryopump, the second cryopump, the third cryopump and the fourth cryopump are heated to a temperature not less than a first temperature threshold, controlling the opening of the fifth baffle valve, the sixth baffle valve, the seventh baffle valve and the eighth baffle valve; when the second vacuum degree measured by the fourth sub-resistance gauge is not less than the first preset vacuum degree, controlling the opening of the second baffle valve; ... After the cryopump is heated to the second temperature threshold, the heating mode is controlled to be turned off; when the second vacuum degree measured by the fourth sub-resistance gauge is less than the second preset vacuum degree, the second baffle valve is controlled to be closed; if the second vacuum degree measured by the fourth sub-resistance gauge rises by more than the first preset rise value, the first cryopump, the second cryopump, the third cryopump and the fourth cryopump are controlled to start the heating mode until the second vacuum degree measured by the fourth sub-resistance gauge is less than the second preset vacuum degree; if the second vacuum degree measured by the fourth sub-resistance gauge rises by no more than the first preset rise value, the first compressor and the second compressor are controlled to be turned on to cool down the first cryopump, the second cryopump, the third cryopump and the fourth cryopump, and the fifth baffle valve, the sixth baffle valve, the seventh baffle valve and the eighth baffle valve are controlled to be closed.

[0013] According to some embodiments of the present invention, when the first vacuum degree of the ion generating device is greater than the maximum preset vacuum degree, the vacuum control device is configured to: control the opening of the first mechanical pump, the first baffle valve, and the fourth baffle valve; when the first vacuum degree of the ion generating device is not greater than the maximum preset vacuum degree, control the opening of the first Roots pump; when the first vacuum degree of the ion generating device is not greater than the minimum preset vacuum degree, control the opening of the first gate valve, the second gate valve, the fifth gate valve, and the sixth gate valve, and control the closing of the fourth baffle valve; control the opening of the first molecular pump, the second molecular pump, the third molecular pump, and the fourth molecular pump; when the first vacuum degree of the ion generating device is not greater than the target vacuum degree, and the secondary cold head temperatures of the first cryogenic pump, the second cryogenic pump, the third cryogenic pump, and the fourth cryogenic pump are all not greater than the preset secondary cold head temperature, control the opening of the third gate valve, the fourth gate valve, the seventh gate valve, and the eighth gate valve.

[0014] According to some embodiments of the present invention, when the first vacuum degree of the ion generating device is not greater than the maximum preset vacuum degree and greater than the minimum preset vacuum degree, the vacuum control device is configured to: control the opening of the first mechanical pump, the first Roots pump, the first baffle valve, and the fourth baffle valve; when the first vacuum degree of the ion generating device is not greater than the minimum preset vacuum degree, control the opening of the first gate valve, the second gate valve, the fifth gate valve, and the sixth gate valve, and control the closing of the fourth baffle valve; control the opening of the first molecular pump, the second molecular pump, the third molecular pump, and the fourth molecular pump; when the first vacuum degree of the ion generating device is not greater than the target vacuum degree, and the secondary cold head temperatures of the first cryogenic pump, the second cryogenic pump, the third cryogenic pump, and the fourth cryogenic pump are all not greater than the preset secondary cold head temperature, control the opening of the third gate valve, the fourth gate valve, the seventh gate valve, and the eighth gate valve.

[0015] According to some embodiments of the present invention, when the first vacuum degree of the ion generating device is not greater than the minimum preset vacuum degree, the vacuum control device is configured to: control the opening of the first mechanical pump, the first Roots pump, and the first baffle valve; control the opening of the first molecular pump, the second molecular pump, the third molecular pump, and the fourth molecular pump; control the opening of the first gate valve, the second gate valve, the fifth gate valve, and the sixth gate valve; when the first vacuum degree of the ion generating device is not greater than the target vacuum degree, and the secondary cold head temperatures of the first cryogenic pump, the second cryogenic pump, the third cryogenic pump, and the fourth cryogenic pump are not greater than the preset secondary cold head temperature, control the opening of the third gate valve, the fourth gate valve, the seventh gate valve, and the eighth gate valve.

[0016] According to some embodiments of the present invention, the vacuum control device is configured to control the vacuum breaking of the ion generating device, including: controlling the opening of the ninth baffle valve; when the first vacuum degree of the ion generating device is greater than the preset vacuum breaking degree, controlling the closing of the ninth baffle valve; controlling the opening of the tenth baffle valve; and controlling the closing of the tenth baffle valve after a preset vacuum breaking time interval.

[0017] According to some embodiments of the present invention, the vacuum control device is configured to control the shutdown of the vacuum system for a compact strong magnetic field ion generating device, including: controlling the sequential closing of the first gate valve, the second gate valve, the third gate valve, the fourth gate valve, the fifth gate valve, the sixth gate valve, the seventh gate valve, the eighth gate valve, the first molecular pump, the second molecular pump, the third molecular pump and the fourth molecular pump, the first baffle valve, the first Roots pump and the first mechanical pump.

[0018] The vacuum system for a compact strong magnetic field ion generating device according to an embodiment of the present invention comprises: an ion generating device; a plurality of molecular pumps and a plurality of cryogenic pumps provided with magnetic field shielding covers, respectively connected to the ion generating device and used to evacuate the ion generating device; a mechanical pump group, respectively connected to the molecular pump and the cryogenic pump through vacuum pipelines, used to serve as a pre-stage of the molecular pump and a regeneration pump of the cryogenic pump; a Roots pump group, respectively connected to the molecular pump and the cryogenic pump through vacuum pipelines, used to cooperate with the mechanical pump group to evacuate the ion generating device; a plurality of pneumatic gate valves, provided between the ion generating device and the plurality of molecular pumps and the plurality of cryogenic pumps, used to control the communication between the plurality of molecular pumps and the plurality of cryogenic pumps and the ion generating device. on and off; a plurality of pneumatic baffle valves are respectively connected to the ion generating device and the vacuum pipeline for controlling the on and off of the vacuum pipeline; a plurality of first resistance gauges are connected to the ion generating device for detecting a first vacuum degree of the ion generating device; a plurality of second resistance gauges are respectively connected to the molecular pump and the cryogenic pump through the vacuum pipeline for detecting a second vacuum degree of the vacuum pipeline; a vacuum control device is respectively connected to the molecular pump, the cryogenic pump, the mechanical pump group, the Roots pump group, the pneumatic plug-in valve, the pneumatic baffle valve, the first resistance gauge, and the second resistance gauge for controlling the molecular pump, the cryogenic pump, the mechanical pump group, the Roots pump group, the pneumatic plug-in valve, and the pneumatic baffle valve according to the first vacuum degree and the second vacuum degree, so as to evacuate the ion generating device to a target vacuum degree. Therefore, the vacuum system integrates the solenoid valve in the solenoid valve box, so that the pneumatic plug valve and pneumatic baffle valve used can be separated from the solenoid valve, and can be kept away from the strong magnetic field environment as a whole, effectively avoiding the influence of the strong magnetic field on the position signal, and the switch position signals of the pneumatic plug valve and pneumatic baffle valve used use mechanical induction signals, which can effectively avoid the interference of the strong magnetic field on the position signal, and the molecular pump used is installed in the molecular pump magnetic field shielding cover, which effectively avoids the influence of the strong magnetic field on the molecular pump. It can also avoid contaminating the vacuum system of the accelerator, and can achieve a higher ultimate vacuum effect by increasing the extraction capacity of water vapor and hydrogen, and can operate in a strong magnetic field environment.

[0019] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is an overall schematic diagram of a vacuum system for a compact high-magnetic field ion generating device according to some embodiments of the present invention;

[0021] Figure 2 An exploded schematic diagram of a magnetic field shield according to some embodiments of the present invention;

[0022] Figure 3 is a schematic cross-sectional view of a magnetic field shield according to some embodiments of the present invention;

[0023] Figure 4 A flow chart of a vacuum control apparatus configured to control cryopump regeneration according to some embodiments of the present invention;

[0024] Figure 5 A flow chart showing that a vacuum control device according to some embodiments of the present invention is configured to control the evacuation of an ion generating device;

[0025] Figure 6 A flow chart showing that a vacuum control device according to some embodiments of the present invention is configured to control the vacuum breaking of an ion generating device;

[0026] Figure 7 A flow chart of a vacuum control device configured to control shutdown of a vacuum system for a compact high magnetic field ion generating device according to some embodiments of the present invention.

[0027] Description of reference numerals:

[0028] an ion generating device 12, a first molecular pump 17, a second molecular pump 18, a third molecular pump 8 and a fourth molecular pump 9, a first cryopump 19, a second cryopump 20, a third cryopump 10, a fourth cryopump 11, a vacuum pipeline 23, a first mechanical pump 1, a second mechanical pump 4, a first Roots pump 2, a second Roots pump 5, a first gate valve 36, a second gate valve 37, a third gate valve 38, a fourth gate valve 39, a fifth gate valve 29, a sixth gate valve 30, a seventh gate valve 31, an eighth gate valve 32, a nitrogen source 22, a first baffle valve 24, a second baffle valve 25, a third baffle valve 26, The fourth baffle valve 35, the fifth baffle valve 40, the sixth baffle valve 41, the seventh baffle valve 27, the eighth baffle valve 28, the third sub-resistance gauge 3, the fourth sub-resistance gauge 6, the ninth baffle valve 33, the tenth baffle valve 34, the first sub-resistance gauge 13, the second sub-resistance gauge 15, the first cold cathode ionization gauge 14, the second cold cathode ionization gauge 16, the first compressor 21, the second compressor 7, the magnetic shielding neck tube 51, the magnetic shielding outer tube 54, the magnetic shielding bottom plate 57, the sealing ring and the sealing ring bracket 52, the sealing plate assembly 55, the first opening 59, the second opening 58, the single-sided C-type caliper bolt 60 and the bolt 61. DETAILED DESCRIPTION

[0029] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0030] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the embodiments of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0031] As shown in the background technology section, the vacuum chamber of the superconducting ion generator is generally sealed by the main magnet and the superconducting coil outer dewar. During the assembly process of the accelerator, residues of cleaning agents such as anhydrous ethanol and acetone, as well as foreign matter such as operator's hand grease and dust, will remain on the inner wall surface. In addition, there is vacuum grease applied on the surface of the rubber ring. These water-based, grease, dust and other residues are easily adsorbed on the inner wall of the vacuum chamber. Before the accelerator vacuum chamber is evacuated, a large amount of dry constant temperature air is required to flush the unsaturated air inside the accelerator and the residual gas adsorbed on the inner wall. At the same time, the inside of the accelerator can also be heated at a low temperature, and then the vacuum chamber is filled with high-purity nitrogen with low adsorption heat, and all air is replaced out of the vacuum chamber. This can greatly shorten the accelerator vacuum system evacuation time and improve the overall vacuum degree of the vacuum chamber of the superconducting ion generator.

[0032] The current ion generator generally uses a diffusion pump or a molecular pump as the main pump. Since the compact ion generator cannot be baked to remove water vapor, the working gas is generally hydrogen. The pneumatic gate valve and pneumatic flapper valve used are equipped with a solenoid valve, and the switch position signal of the pneumatic gate valve and pneumatic flapper valve generally adopts a magnetic induction signal.

[0033] In the process of implementing the present invention, the applicant found that the diffusion pump has high power consumption, is easy to pollute the accelerator vacuum, is large in size, and is not convenient for use in compact accelerators. The molecular pump has poor effect on water vapor and hydrogen extraction, so using only the molecular pump as the main pump is not conducive to the extraction of extreme vacuum. In a strong magnetic field environment, the solenoid valve and the magnetic induction signal will be disturbed by the strong magnetic field, and the rotating rotor will generate eddy current and heat in a strong magnetic field environment, so it cannot be used in a strong magnetic field environment.

[0034] The following describes a vacuum system for a compact high magnetic field ion generating device according to an embodiment of the present invention with reference to the accompanying drawings.

[0035] refer to Figure 1 , is an overall schematic diagram of a vacuum system for a compact strong magnetic field ion generating device according to some embodiments of the present invention.

[0036] The vacuum system for a compact high-magnetic field ion generating device provided by the present invention comprises: an ion generating device 12, a molecular pump, a cryogenic pump, a mechanical pump group, a Roots pump group, a pneumatic plug valve, a pneumatic baffle valve, a first resistance gauge, a second resistance gauge, a vacuum control device, a magnetic field shielding cover, a vacuum pipeline 23, a nitrogen source 22, a first compressor 21, a second compressor 7, a solenoid valve (not shown in the figure) and a solenoid valve box (not shown in the figure).

[0037] The molecular pump includes a first molecular pump 17, a second molecular pump 18, a third molecular pump 8 and a fourth molecular pump 9, and the cryopump includes a first cryopump 19, a second cryopump 20, a third cryopump 10 and a fourth cryopump 11. The molecular pump and the cryopump are used as main pumps. A plurality of molecular pumps provided with magnetic field shields and a plurality of cryopumps are respectively connected to the ion generator 12, and are used to evacuate the ion generator 12.

[0038] The mechanical pump group is connected to the molecular pump and the cryogenic pump respectively through the vacuum pipeline 23, and is used as the front stage of the molecular pump and the regeneration pump of the cryogenic pump. It should be explained that since the molecular pump has a poor effect on the pumping of water vapor and hydrogen, it is necessary to first use the mechanical pump group for rough vacuuming, and then use the molecular pump for vacuuming to achieve a higher ultimate vacuum, so the mechanical pump group can be used as the front stage pump of the molecular pump.

[0039] The mechanical pump group includes a first mechanical pump 1 and a second mechanical pump 4. The first mechanical pump 1 is connected to the first molecular pump 17, the second molecular pump 18, the third molecular pump 8 and the fourth molecular pump 9 through a vacuum pipeline 23. The second mechanical pump 4 is connected to the first cryogenic pump 19, the second cryogenic pump 20, the third cryogenic pump 10 and the fourth cryogenic pump 11 through a vacuum pipeline 23.

[0040] The Roots pump group is connected to the molecular pump and the cryogenic pump respectively through the vacuum pipeline 23 , and is used to cooperate with the mechanical pump group to evacuate the ion generating device 12 .

[0041] The Roots pump group includes a first Roots pump 2 and a second Roots pump 5, one end of the first Roots pump 2 is connected to the first mechanical pump 1 through a vacuum pipeline 23, the other end of the first Roots pump 2 is connected to the first molecular pump 17, the second molecular pump 18, the third molecular pump 8 and the fourth molecular pump 9 through the vacuum pipeline 23, one end of the second Roots pump 5 is connected to the second mechanical pump 4 through the vacuum pipeline 23, and the other end of the second Roots pump 5 is connected to the first cryogenic pump 19, the second cryogenic pump 20, the third cryogenic pump 10 and the fourth cryogenic pump 11 through the vacuum pipeline 23.

[0042] A plurality of pneumatic gate valves are arranged between the ion generating device 12 and the plurality of molecular pumps and the plurality of cryogenic pumps, and are used to control the on-off between the plurality of molecular pumps and the plurality of cryogenic pumps and the ion generating device 12 .

[0043] The pneumatic gate valve includes a first gate valve 36, a second gate valve 37, a third gate valve 38, a fourth gate valve 39, a fifth gate valve 29, a sixth gate valve 30, a seventh gate valve 31, and an eighth gate valve 32. The first gate valve 36 is arranged between the ion generator 12 and the first molecular pump 17, the second gate valve 37 is arranged between the ion generator 12 and the second molecular pump 18, the third gate valve 38 is arranged between the ion generator 12 and the first cryogenic pump 19, the fourth gate valve 39 is arranged between the ion generator 12 and the second cryogenic pump 20, the fifth gate valve 29 is arranged between the ion generator 12 and the third molecular pump 8, the sixth gate valve 30 is arranged between the ion generator 12 and the fourth molecular pump 9, the seventh gate valve 31 is arranged between the ion generator 12 and the third cryogenic pump 10, and the eighth gate valve 32 is arranged between the ion generator 12 and the fourth cryogenic pump 11. The switch position signal of the gate valve adopts a mechanical induction signal to avoid the switch position signal being affected by a strong magnetic field.

[0044] The vacuum system for the compact high-magnetic field ion generator further comprises a nitrogen source 22 , which is connected to the ion generator 12 and is used to fill the ion generator 12 with nitrogen to break the vacuum of the ion generator 12 .

[0045] A plurality of first resistance gauges are connected to the ion generator 12 for detecting the first vacuum degree of the ion generator 12. The first resistance gauge comprises a first sub-resistance gauge 13 and a second sub-resistance gauge 15, wherein the first sub-resistance gauge 13 is connected in parallel with a first cold cathode ionization gauge 14, and the second sub-resistance gauge 15 is connected in parallel with a second cold cathode ionization gauge 16.

[0046] The plurality of second resistance gauges are respectively connected to the molecular pump and the cryogenic pump through the vacuum pipeline 23, and are used to detect the second vacuum degree of the vacuum pipeline 23. The second resistance gauge includes a third sub-resistance gauge 3 and a fourth sub-resistance gauge 6, the third sub-resistance gauge 3 is arranged between the first Roots pump 2 and the first molecular pump 17, the second molecular pump 18, the third molecular pump 8 and the fourth molecular pump 9, and the fourth sub-resistance gauge 6 is arranged between the second Roots pump 5 and the first cryogenic pump 19, the second cryogenic pump 20, the third cryogenic pump 10 and the fourth cryogenic pump 11.

[0047] A plurality of pneumatic baffle valves are respectively connected to the ion generating device 12 and the vacuum pipeline 23 , and are used to control the on-off of the vacuum pipeline 23 .

[0048] The pneumatic damper valve includes a first damper valve 24, a second damper valve 25, a third damper valve 26, a fourth damper valve 35, a fifth damper valve 40, a sixth damper valve 41, a seventh damper valve 27, and an eighth damper valve 28. The first damper valve 24 is arranged between the first Roots pump 2 and the third sub-resistance gauge 3, the second damper valve 25 is arranged between the second Roots pump 5 and the fourth sub-resistance gauge 6, the third damper valve 26 is arranged between the third sub-resistance gauge 3 and the fourth sub-resistance gauge 6, the fourth damper valve 35 is arranged between the third sub-resistance gauge 3 and the ion generating device 12, the fifth damper valve 40 is arranged between the first cryogenic pump 19 and the fourth sub-resistance gauge 6, the sixth damper valve 41 is arranged between the second cryogenic pump 20 and the fourth sub-resistance gauge 6, the seventh damper valve 27 is arranged between the third cryogenic pump 10 and the fourth sub-resistance gauge 6, and the eighth damper valve 28 is arranged between the fourth cryogenic pump 11 and the fourth sub-resistance gauge 6.

[0049] It should be noted that in the embodiment of the present application, the switch position signal of the baffle valve preferably adopts a mechanical induction signal, in order to prevent the switch position signal from being affected by a strong magnetic field.

[0050] The pneumatic baffle valve also includes a ninth baffle valve 33 and a tenth baffle valve 34. The ninth baffle valve 33 is arranged between the nitrogen source 22 and the ion generating device 12, and the tenth baffle valve 34 is arranged between the ninth baffle valve 33 and the ion generating device 12. The ninth baffle valve 33 and the tenth baffle valve 34 are used to adjust the flow rate of nitrogen entering the ion generating device 12.

[0051] The vacuum control device is respectively connected to the molecular pump, the cryogenic pump, the mechanical pump group, the Roots pump group, the pneumatic plug-in valve, the pneumatic baffle valve, the first resistance gauge, and the second resistance gauge, and is used to control the molecular pump, the cryogenic pump, the mechanical pump group, the Roots pump group, the pneumatic plug-in valve, and the pneumatic baffle valve according to the first vacuum degree and the second vacuum degree, so as to evacuate the ion generating device 12 to the target vacuum degree.

[0052] refer to Figure 2, is an explosion diagram of a magnetic field shielding cover according to some embodiments of the present invention, the molecular pump is arranged inside the magnetic field shielding cover, which can effectively avoid the influence of a strong magnetic field on the molecular pump, wherein the magnetic field shielding cover comprises a magnetic shielding neck tube 51, a magnetic shielding outer cylinder 54, a magnetic shielding bottom plate 57, a single-sided C-type caliper bolt 60 and a bolt 61, the magnetic shielding neck tube 51 can shield most of the magnetic field entering the molecular pump from the molecular pump port, the magnetic shielding outer cylinder 54 can shield the magnetic field entering the molecular pump from the side of the molecular pump, the magnetic shielding bottom plate 57 can shield the magnetic field entering the molecular pump from the bottom of the molecular pump, the single-sided C-type caliper bolt 60 and the bolt 61 are used to fasten the magnetic shielding neck tube 51 to the molecular pump, wherein the magnetic shielding material can be made of 45# steel plate, 10# steel plate, silicon steel, high-quality steel (DT4) with an iron content of more than 99.5%, carbon structural steel (Q235), etc., reference Figure 3 , is a cross-sectional schematic diagram of a magnetic field shielding cover according to some embodiments of the present invention, one end of a magnetic shielding neck tube 51 is connected to the pump port of a molecular pump through a sealing ring and a sealing ring bracket 52, one end of a magnetic shielding outer tube 54 is connected to the magnetic shielding neck tube 51, and the other end is connected to a magnetic shielding bottom plate 57.

[0053] The magnetic field shielding cover also includes a sealing plate assembly 55, which can reduce the magnetic leakage of the opening of the magnetic shielding outer cylinder 54. The magnetic shielding outer cylinder 54 is provided with a first opening 59 and a second opening 58. For example, the first opening 59 can be a cable hole, and the second opening 58 can be a front-stage pipeline hole. The first opening 59 is used to connect the cable of the molecular pump with the molecular pump in the magnetic field shielding cover, and the second opening 58 is used to connect the vacuum pipeline 23 with the molecular pump in the magnetic field shielding cover.

[0054] The above-mentioned vacuum system for the compact strong magnetic field ion generating device also includes a first compressor 21 and a second compressor 7. The first compressor 21 is connected to the first cryopump 19 and the second cryopump 20, and the second compressor 7 is connected to the third cryopump 10 and the fourth cryopump 11, which are used to cool the first cryopump 19, the second cryopump 20, the third cryopump 10 and the fourth cryopump 11.

[0055] As a specific embodiment, the above-mentioned vacuum system for a compact strong magnetic field ion generating device may also include a solenoid valve and a solenoid valve box. The solenoid valve is integrated in the solenoid valve box to separate the gate valve and the baffle valve from the solenoid valve. The solenoid valve is used to control the switching status of eight gate valves and ten baffle valves. The solenoid valve can be connected to the gate valve and the baffle valve through an extended air pipe, and the solenoid valve box can be placed in a strong magnetic field area away from the ion generating device to avoid interference of the strong magnetic field on the solenoid valve box.

[0056] Therefore, the vacuum system of the compact high magnetic field ion generator of the present invention can provide an ultra-high vacuum environment for the accelerator to reduce beam loss, reduce gas radiation, and increase the insulation strength of the radio frequency resonant cavity. As a key auxiliary system of the ion generator, the vacuum system can directly affect the stability of the accelerator.

[0057] In some embodiments of the present invention, the vacuum control device is configured to control the regeneration of the cryopump, including: controlling the closing of the third gate valve 38, the fourth gate valve 39, the seventh gate valve 31, the eighth gate valve 32, the first compressor 21 and the second compressor 7, and starting the second mechanical pump 4 and the second Roots pump 5; controlling the first cryopump 19, the second cryopump 20, the third cryopump 10 and the fourth cryopump 11 to start the heating mode, when the first cryopump 19, the second cryopump 20, the third cryopump 10 and the fourth cryopump 11 are heated to a temperature not less than the first temperature threshold, controlling the opening of the fifth baffle valve 40, the sixth baffle valve 41, the seventh baffle valve 27 and the eighth baffle valve 28; when the second vacuum degree measured by the fourth sub-resistance gauge 6 is not less than the first preset vacuum degree, controlling the opening of the second baffle valve 25; ... After the pump 10 and the fourth cryopump 11 are heated to the second temperature threshold, the heating mode is controlled to be turned off; when the second vacuum degree measured by the fourth sub-resistance gauge 6 is less than the second preset vacuum degree, the second damper valve 25 is controlled to be closed; if the second vacuum degree measured by the fourth sub-resistance gauge 6 rises by more than the first preset rise value, the first cryopump 19, the second cryopump 20, the third cryopump 10 and the fourth cryopump 11 are controlled to start the heating mode until the second vacuum degree measured by the fourth sub-resistance gauge 6 is less than the second preset vacuum degree; if the second vacuum degree measured by the fourth sub-resistance gauge 6 rises by no more than the first preset rise value, the first compressor 21 and the second compressor 7 are controlled to be turned on to cool down the first cryopump 19, the second cryopump 20, the third cryopump 10 and the fourth cryopump 11, and the fifth damper valve 40, the sixth damper valve 41, the seventh damper valve 27 and the eighth damper valve 28 are controlled to be closed. Among them, the first temperature threshold, the first preset vacuum degree, the second temperature threshold, the second preset vacuum degree and the first preset rise value can be calibrated according to actual conditions.

[0058] Specifically, when a vacuum state is required, the vacuum control device is configured to control the regeneration of the cryopump. First, the third gate valve 38, the fourth gate valve 39, the seventh gate valve 31, the eighth gate valve 32, the first compressor 21 and the second compressor 7 are controlled to be closed in sequence, and the second mechanical pump 4 and the second Roots pump 5 are turned on in sequence, and the first cryopump 19, the second cryopump 20, the third cryopump 10 and the fourth cryopump 11 are controlled to turn on the heating mode in sequence to promote the release of the adsorbed gas. The heating temperature of the cryopump can be detected by a temperature sensor arranged inside the cryopump. When the first cryopump 19, the second cryopump 20, the third cryopump 10 and the fourth cryopump 11 are heated to a temperature not less than a first temperature threshold (such as 150K), the fifth baffle valve 40, the sixth baffle valve 41, the seventh baffle valve 27 and the eighth baffle valve 28 are controlled to be opened in sequence. The vacuum degree can be detected by a vacuum degree sensor arranged inside the resistance gauge. When the second vacuum degree measured by the fourth sub-resistance gauge 6 is not less than the first preset vacuum degree (10Pa), the second damper valve 25 is controlled to be opened. After the first cryopump 19, the second cryopump 20, the third cryopump 10 and the fourth cryopump 11 are heated to the second temperature threshold (310K), they are kept warm for a certain time (such as 30min) and then the heating mode is controlled to be closed. When the second vacuum degree measured by the fourth sub-resistance gauge 6 is less than the second preset vacuum degree (5Pa), the second damper valve 25 is controlled to be closed after a certain time (such as 10min). The second vacuum degree measured by the fourth sub-resistance gauge 6 is judged. If the second vacuum degree measured by the fourth sub-resistance gauge 6 rises by more than the first preset rise value (such as 6Pa / min), the first cryopump 19, the second cryopump 20, the third cryopump 10 and the fourth cryopump 11 are controlled to start the heating mode in sequence until the second vacuum degree measured by the fourth sub-resistance gauge 6 is less than the second preset vacuum degree. If the second vacuum degree rise measured by the fourth sub-resistance gauge 6 is not greater than the first preset rise value, the first compressor 21 and the second compressor 7 are sequentially controlled to be turned on to cool down the first cryopump 19, the second cryopump 20, the third cryopump 10 and the fourth cryopump 11, and then the fifth baffle valve 40, the sixth baffle valve 41, the seventh baffle valve 27 and the eighth baffle valve 28 are sequentially controlled to be closed. The temperature of the secondary cold head of the cryopump can be detected by a temperature sensor disposed inside the cryopump. When the secondary cold head temperatures of the first cryopump 19, the second cryopump 20, the third cryopump 10 and the fourth cryopump 11 are all less than 14K, it indicates that the cryopump regeneration is completed.

[0059] As a specific example, Figure 4 As shown, the vacuum control device of the present invention is configured to control the regeneration of the cryopump and may include the following steps:

[0060] S401, controlling the closing of the third gate valve, the fourth gate valve, the seventh gate valve, the eighth gate valve, the first compressor and the second compressor.

[0061] S402, start the second mechanical pump and the second Roots pump.

[0062] S403, controlling the first cryopump, the second cryopump, the third cryopump, and the fourth cryopump to start a heating mode.

[0063] S404, when the first cryopump, the second cryopump, the third cryopump and the fourth cryopump are heated to a temperature not less than a first temperature threshold, the fifth damper valve, the sixth damper valve, the seventh damper valve and the eighth damper valve are controlled to open.

[0064] S405, when the second vacuum degree measured by the fourth sub-resistance gauge is not less than the first preset vacuum degree, control the second flapper valve to open.

[0065] S406 , when the first cryopump, the second cryopump, the third cryopump, and the fourth cryopump are heated to a second temperature threshold, controlling to turn off the heating mode.

[0066] S407, when the second vacuum degree measured by the fourth sub-resistance gauge is less than the second preset vacuum degree, controlling the second flapper valve to close.

[0067] S408, determining whether the second vacuum degree rise measured by the fourth sub-resistance gauge is greater than the first preset rise value. If yes, executing step S409; if no, executing step S410.

[0068] S409, controlling the first cryopump, the second cryopump, the third cryopump and the fourth cryopump to start a heating mode until the second vacuum degree measured by the fourth sub-resistance gauge is less than the second preset vacuum degree.

[0069] S410, controlling to open the first compressor and the second compressor to cool down the first cryopump, the second cryopump, the third cryopump and the fourth cryopump, and controlling to close the fifth damper valve, the sixth damper valve, the seventh damper valve and the eighth damper valve.

[0070] In some embodiments of the present invention, when the first vacuum degree of the ion generating device 12 is greater than the maximum preset vacuum degree, the vacuum control device is configured to: control the opening of the first mechanical pump 1, the first baffle valve 24, and the fourth baffle valve 35; when the first vacuum degree of the ion generating device 12 is not greater than the maximum preset vacuum degree, control the opening of the first Roots pump 2; when the first vacuum degree of the ion generating device 12 is not greater than the minimum preset vacuum degree, control the opening of the first gate valve 36, the second gate valve 37, the fifth gate valve 29, and the sixth gate valve 30, and control the closing of the fourth baffle valve 35; control the opening of the first molecular pump 17, the second molecular pump 18, the third molecular pump 8, and the fourth molecular pump 9; when the first vacuum degree of the ion generating device 12 is not greater than the target vacuum degree, and the secondary cold head temperatures of the first cryogenic pump 19, the second cryogenic pump 20, the third cryogenic pump 10, and the fourth cryogenic pump 11 are all not greater than the preset secondary cold head temperature, control the opening of the third gate valve 38, the fourth gate valve 39, the seventh gate valve 31, and the eighth gate valve 32. Among them, the maximum preset vacuum degree, the minimum preset vacuum degree, the target vacuum degree and the preset secondary cold head temperature can be calibrated according to actual conditions.

[0071] Specifically, when the first vacuum degree of the ion generating device 12 is greater than the maximum preset vacuum degree (such as 1000Pa), the vacuum control device is configured to evacuate. The first mechanical pump 1, the first baffle valve 24, and the fourth baffle valve 35 are controlled to be turned on in sequence. When the first vacuum degree of the ion generating device 12 is not greater than the maximum preset vacuum degree, the first Roots pump 2 is controlled to be turned on. When the first vacuum degree of the ion generating device 12 is not greater than the minimum preset vacuum degree (such as 10Pa), the first plug valve 36, the second plug valve 37, the fifth plug valve 29, and the sixth plug valve 30 are controlled to be opened in sequence, the fourth baffle valve 35 is controlled to be closed, and the first molecular pump 17, the second molecular pump 18, the third molecular pump 8, and the fourth molecular pump 9 are controlled to be turned on in sequence. When the first vacuum degree of the ion generating device 12 is not greater than the target vacuum degree (such as 1E-2Pa), and the secondary cold head temperatures of the first cryopump 19, the second cryopump 20, the third cryopump 10 and the fourth cryopump 11 are all not greater than the preset secondary cold head temperature (such as 14K), the third gate valve 38, the fourth gate valve 39, the seventh gate valve 31 and the eighth gate valve 32 are controlled to open in sequence.

[0072] In some embodiments of the present invention, when the first vacuum degree of the ion generating device 12 is not greater than the maximum preset vacuum degree and greater than the minimum preset vacuum degree, the vacuum control device is configured to: control the opening of the first mechanical pump 1, the first Roots pump 2, the first baffle valve 24, and the fourth baffle valve 35; when the first vacuum degree of the ion generating device 12 is not greater than the minimum preset vacuum degree, control the opening of the first gate valve 36, the second gate valve 37, the fifth gate valve 29, and the sixth gate valve 30, and control the closing of the fourth baffle valve 35; control the opening of the first molecular pump 17, the second molecular pump 18, the third molecular pump 8, and the fourth molecular pump 9; when the first vacuum degree of the ion generating device 12 is not greater than the target vacuum degree, and the secondary cold head temperatures of the first cryogenic pump 19, the second cryogenic pump 20, the third cryogenic pump 10, and the fourth cryogenic pump 11 are all not greater than the preset secondary cold head temperature, control the opening of the third gate valve 38, the fourth gate valve 39, the seventh gate valve 31, and the eighth gate valve 32.

[0073] Specifically, when the first vacuum degree of the ion generating device 12 is not greater than the maximum preset vacuum degree and greater than the minimum preset vacuum degree, the vacuum control device is configured to evacuate. The first mechanical pump 1, the first Roots pump 2, the first baffle valve 24, and the fourth baffle valve 35 are controlled to be opened in sequence. When the first vacuum degree of the ion generating device 12 is not greater than the minimum preset vacuum degree, the first gate valve 36, the second gate valve 37, the fifth gate valve 29, and the sixth gate valve 30 are controlled to be opened in sequence, and the fourth baffle valve 35 is controlled to be closed, and the first molecular pump 17, the second molecular pump 18, the third molecular pump 8, and the fourth molecular pump 9 are controlled to be opened in sequence. When the first vacuum degree of the ion generating device 12 is not greater than the target vacuum degree, and the secondary cold head temperatures of the first cryopump 19, the second cryopump 20, the third cryopump 10, and the fourth cryopump 11 are not greater than the preset secondary cold head temperature, the third gate valve 38, the fourth gate valve 39, the seventh gate valve 31, and the eighth gate valve 32 are controlled to be opened in sequence.

[0074] In some embodiments of the present invention, when the first vacuum degree of the ion generating device 12 is not greater than the minimum preset vacuum degree, the vacuum control device is configured to: control the opening of the first mechanical pump 1, the first Roots pump 2, and the first baffle valve 24; control the opening of the first molecular pump 17, the second molecular pump 18, the third molecular pump 8 and the fourth molecular pump 9; control the opening of the first gate valve 36, the second gate valve 37, the fifth gate valve 29 and the sixth gate valve 30; when the first vacuum degree of the ion generating device 12 is not greater than the target vacuum degree, and the secondary cold head temperatures of the first cryogenic pump 19, the second cryogenic pump 20, the third cryogenic pump 10 and the fourth cryogenic pump 11 are not greater than the preset secondary cold head temperature, control the opening of the third gate valve 38, the fourth gate valve 39, the seventh gate valve 31, and the eighth gate valve 32.

[0075] Specifically, when the first vacuum degree of the ion generating device 12 is not greater than the minimum preset vacuum degree, the vacuum control device is configured to evacuate. The first mechanical pump 1, the first Roots pump 2, and the first baffle valve 24 are controlled to be opened in sequence, and the first molecular pump 17, the second molecular pump 18, the third molecular pump 8, and the fourth molecular pump 9 are controlled to be opened in sequence, and the first plug valve 36, the second plug valve 37, the fifth plug valve 29, and the sixth plug valve 30 are controlled to be opened in sequence. When the first vacuum degree of the ion generating device 12 is not greater than the target vacuum degree, and the secondary cold head temperatures of the first cryopump 19, the second cryopump 20, the third cryopump 10, and the fourth cryopump 11 are not greater than the preset secondary cold head temperature, the third plug valve 38, the fourth plug valve 39, the seventh plug valve 31, and the eighth plug valve 32 are controlled to be opened in sequence.

[0076] As a specific example, Figure 5 As shown, the vacuum control device of the present invention is configured to control the vacuuming of the ion generating device and may include the following steps:

[0077] S501, determining whether the first vacuum degree of the ion generating device is greater than the maximum preset vacuum degree. If yes, executing step S502; if no, executing step S508.

[0078] S502, control to open the first mechanical pump, the first flapper valve, and the fourth flapper valve.

[0079] S503, when the first vacuum degree of the ion generating device is not greater than the maximum preset vacuum degree, control to start the first Roots pump.

[0080] S504, when the first vacuum degree of the ion generating device is not greater than the minimum preset vacuum degree, control the opening of the first gate valve, the second gate valve, the fifth gate valve, and the sixth gate valve.

[0081] S505, controlling the closing of the fourth damper valve.

[0082] S506, controlling to start the first molecular pump, the second molecular pump, the third molecular pump and the fourth molecular pump.

[0083] S507, when the first vacuum degree of the ion generating device is not greater than the target vacuum degree, and the secondary cold head temperatures of the first cryopump, the second cryopump, the third cryopump and the fourth cryopump are not greater than the preset secondary cold head temperature, control the opening of the third gate valve, the fourth gate valve, the seventh gate valve and the eighth gate valve.

[0084] S508, determining whether the first vacuum degree of the ion generating device is not greater than the maximum preset vacuum degree and greater than the minimum preset vacuum degree. If yes, execute step S509; if not, execute step S514.

[0085] S509, controlling to open the first mechanical pump, the first Roots pump, the first flapper valve, and the fourth flapper valve.

[0086] S510, when the first vacuum degree of the ion generating device is not greater than the minimum preset vacuum degree, control to open the first gate valve, the second gate valve, the fifth gate valve and the sixth gate valve.

[0087] S511, controlling the closing of the fourth damper valve.

[0088] S512, controlling to start the first molecular pump, the second molecular pump, the third molecular pump and the fourth molecular pump.

[0089] S513, when the first vacuum degree of the ion generating device is not greater than the target vacuum degree, and the secondary cold head temperatures of the first cryopump, the second cryopump, the third cryopump and the fourth cryopump are not greater than the preset secondary cold head temperature, control the opening of the third gate valve, the fourth gate valve, the seventh gate valve and the eighth gate valve.

[0090] S514, controlling to open the first mechanical pump, the first Roots pump, and the first baffle valve.

[0091] S515, controlling to start the first molecular pump, the second molecular pump, the third molecular pump and the fourth molecular pump.

[0092] S516, controlling to open the first gate valve, the second gate valve, the fifth gate valve and the sixth gate valve.

[0093] S517, when the first vacuum degree of the ion generating device is not greater than the target vacuum degree, and the secondary cold head temperatures of the first cryopump, the second cryopump, the third cryopump and the fourth cryopump are not greater than the preset secondary cold head temperature, control the opening of the third gate valve, the fourth gate valve, the seventh gate valve and the eighth gate valve.

[0094] In some embodiments of the present invention, the vacuum control device is configured to control the ion generating device 12 to break vacuum, including: controlling to open the ninth flapper valve 33; when the first vacuum degree of the ion generating device 12 is greater than the preset vacuum breaking degree, controlling to close the ninth flapper valve 33; controlling to open the tenth flapper valve 34; after the preset vacuum breaking time interval, controlling to close the tenth flapper valve 34. The preset vacuum breaking degree and the preset vacuum breaking time interval can be calibrated according to actual conditions.

[0095] Specifically, when the ion generating device 12 needs to be in an open state, the vacuum control device is configured to control the ion generating device 12 to break the vacuum. First, the ninth flapper valve 33 is controlled to be opened. When the first vacuum degree of the ion generating device 12 is greater than the preset vacuum breaking degree, the ninth flapper valve 33 is controlled to be closed, and then the tenth flapper valve 34 is controlled to be opened to avoid a pressure difference between the inside of the ion generating device 12 and the atmosphere. After a preset vacuum breaking time interval (such as 1 minute), the tenth flapper valve 34 is controlled to be closed.

[0096] It should be explained that before the vacuum control device is configured to control the ion generating device 12 to break the vacuum, it is necessary to ensure that the vacuum control device has been shut down.

[0097] As a specific example, Figure 6 As shown, the vacuum control device of the present invention is configured to control the ion generating device to break the vacuum, which may include the following steps:

[0098] S601, control to open the ninth damper valve.

[0099] S602, when the first vacuum degree of the ion generating device is greater than the preset vacuum breaking degree, the ninth baffle valve is controlled to close.

[0100] S603, controlling to open the tenth damper valve.

[0101] S604, after a preset vacuum breaking time interval, controlling to close the tenth flapper valve.

[0102] In some embodiments of the present invention, the vacuum control device is configured to control the shutdown of the vacuum system for the compact strong magnetic field ion generating device 12, including: controlling the sequential closing of the first gate valve 36, the second gate valve 37, the third gate valve 38, the fourth gate valve 39, the fifth gate valve 29, the sixth gate valve 30, the seventh gate valve 31, the eighth gate valve 32, the first molecular pump 17, the second molecular pump 18, the third molecular pump 8 and the fourth molecular pump 9, the first baffle valve 24, the first Roots pump 2 and the first mechanical pump 1.

[0103] Specifically, when the ion generator 12 needs to be shut down, the vacuum control device is configured to control the shutdown of the vacuum system for the compact strong magnetic field ion generator 12. The first gate valve 36, the second gate valve 37, the third gate valve 38, the fourth gate valve 39, the fifth gate valve 29, the sixth gate valve 30, the seventh gate valve 31, the eighth gate valve 32, the first molecular pump 17, the second molecular pump 18, the third molecular pump 8 and the fourth molecular pump 9, the first flapper valve 24, the first Roots pump 2 and the first mechanical pump 1 are sequentially closed in sequence.

[0104] As a specific example, Figure 7As shown, the vacuum control device of the present invention is configured to control the shutdown of the vacuum system of the compact high-magnetic field ion generating device and may include the following steps:

[0105] S701, control to close the first gate valve, the second gate valve, the third gate valve, the fourth gate valve, the fifth gate valve, the sixth gate valve, the seventh gate valve, and the eighth gate valve in sequence.

[0106] S702, controlling to sequentially shut down the first molecular pump, the second molecular pump, the third molecular pump, and the fourth molecular pump.

[0107] S703, controlling the closing of the first flapper valve.

[0108] S704, control to close the first Roots pump.

[0109] S705, controlling to shut down the first mechanical pump.

[0110] In summary, the vacuum system for a compact strong magnetic field ion generating device according to an embodiment of the present invention comprises: an ion generating device; a plurality of molecular pumps provided with magnetic field shielding covers and a plurality of cryogenic pumps, which are respectively connected to the ion generating device and are used to evacuate the ion generating device; a mechanical pump group, which is respectively connected to the molecular pump and the cryogenic pump through vacuum pipelines and is used to serve as a pre-stage of the molecular pump and a regeneration pump of the cryogenic pump; a Roots pump group, which is respectively connected to the molecular pump and the cryogenic pump through vacuum pipelines and is used to cooperate with the mechanical pump group to evacuate the ion generating device; a plurality of pneumatic gate valves, which are provided between the ion generating device and the plurality of molecular pumps and the plurality of cryogenic pumps and are used to control the plurality of molecular pumps and the plurality of cryogenic pumps and the ion generating device. on and off; multiple pneumatic baffle valves, respectively connected to the ion generating device and the vacuum pipeline, for controlling the on and off of the vacuum pipeline; multiple first resistance gauges, connected to the ion generating device, for detecting the first vacuum degree of the ion generating device; multiple second resistance gauges, respectively connected to the molecular pump and the cryogenic pump through the vacuum pipeline, for detecting the second vacuum degree of the vacuum pipeline; a vacuum control device, respectively connected to the molecular pump, the cryogenic pump, the mechanical pump group, the Roots pump group, the pneumatic plug-in valve, the pneumatic baffle valve, the first resistance gauge, and the second resistance gauge, for controlling the molecular pump, the cryogenic pump, the mechanical pump group, the Roots pump group, the pneumatic plug-in valve and the pneumatic baffle valve according to the first vacuum degree and the second vacuum degree, so as to evacuate the ion generating device to the target vacuum degree. Therefore, the vacuum system integrates the solenoid valve in the solenoid valve box, so that the pneumatic plug valve and pneumatic baffle valve used can be separated from the solenoid valve, and can be kept away from the strong magnetic field environment as a whole, effectively avoiding the influence of the strong magnetic field on the position signal, and the switch position signals of the pneumatic plug valve and pneumatic baffle valve used use mechanical induction signals, which can effectively avoid the interference of the strong magnetic field on the position signal, and the molecular pump used is installed in the molecular pump magnetic field shielding cover, which effectively avoids the influence of the strong magnetic field on the molecular pump. It can also avoid contaminating the vacuum system of the accelerator, and can achieve a higher ultimate vacuum effect by increasing the extraction capacity of water vapor and hydrogen, and can operate in a strong magnetic field environment.

[0111] It should be noted that the above describes some embodiments of the present invention. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0112] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the embodiments of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0113] Although the spirit and principles of the present invention have been described with reference to several specific embodiments, it should be understood that the present invention is not limited to the specific embodiments disclosed, and the division into various aspects does not mean that the features in these aspects cannot be combined to benefit. This division is only for convenience of expression.

Claims

1. A vacuum system for a compact high-magnetic field ion generator, characterized in that: include: Ion generating device (12); A plurality of molecular pumps provided with magnetic field shielding covers and a plurality of cryogenic pumps, respectively connected to the ion generating device (12), and all used to evacuate the ion generating device (12); A mechanical pump group, connected to the molecular pump and the cryogenic pump respectively through a vacuum pipeline (23), and used as a front stage of the molecular pump and a regeneration pump of the cryogenic pump; A Roots pump group, connected to the molecular pump and the cryogenic pump respectively through a vacuum pipeline (23), and used to cooperate with the mechanical pump group to evacuate the ion generating device (12); a plurality of pneumatic gate valves, arranged between the ion generating device (12) and the plurality of molecular pumps and the plurality of cryogenic pumps, and used for controlling the on-off between the plurality of molecular pumps and the plurality of cryogenic pumps and the ion generating device (12); A plurality of pneumatic flapper valves, respectively connected to the ion generating device (12) and the vacuum pipeline (23), and used for controlling the on and off of the vacuum pipeline (23); a plurality of first resistance gauges connected to the ion generating device (12) and used to detect a first vacuum degree of the ion generating device (12); a plurality of second resistance gauges, respectively connected to the molecular pump and the cryogenic pump via a vacuum pipeline (23), and used to detect a second vacuum degree of the vacuum pipeline (23); A vacuum control device is connected to the molecular pump, the cryogenic pump, the mechanical pump group, the Roots pump group, the pneumatic plug valve, the pneumatic baffle valve, the first resistance gauge, and the second resistance gauge, respectively, and is used to control the molecular pump, the cryogenic pump, the mechanical pump group, the Roots pump group, the pneumatic plug valve, and the pneumatic baffle valve according to the first vacuum degree and the second vacuum degree, so as to evacuate the ion generating device (12) to a target vacuum degree.

2. The vacuum system for a compact high-magnetic field ion generator according to claim 1, characterized in that: The molecular pump is arranged inside the magnetic field shield; The magnetic field shielding cover comprises a magnetic shielding neck tube (51), a magnetic shielding outer cylinder (54), and a magnetic shielding bottom plate (57); one end of the magnetic shielding neck tube (51) is connected to the pump port of the molecular pump via a sealing ring and a sealing ring bracket (52); one end of the magnetic shielding outer cylinder (54) is connected to the magnetic shielding neck tube (51), and the other end is connected to the magnetic shielding bottom plate (57).

3. The vacuum system for a compact high-magnetic field ion generator according to claim 2, characterized in that: The magnetic field shielding cover also includes a sealing plate assembly (55), and the magnetic shielding outer cylinder (54) is provided with a first opening (59) and a second opening (58), the first opening (59) being used to connect the cable of the molecular pump with the molecular pump in the magnetic field shielding cover, and the second opening (58) being used to connect the vacuum pipeline (23) with the molecular pump in the magnetic field shielding cover.

4. The vacuum system for a compact high-magnetic field ion generator according to claim 1, characterized in that: The molecular pump comprises a first molecular pump (17), a second molecular pump (18), a third molecular pump (8) and a fourth molecular pump (9); The cryopumps comprise a first cryopump (19), a second cryopump (20), a third cryopump (10) and a fourth cryopump (11); The mechanical pump group comprises a first mechanical pump (1) and a second mechanical pump (4); the first mechanical pump (1) is connected to the first molecular pump (17), the second molecular pump (18), the third molecular pump (8) and the fourth molecular pump (9) via a vacuum pipeline (23); the second mechanical pump (4) is connected to the first cryogenic pump (19), the second cryogenic pump (20), the third cryogenic pump (10) and the fourth cryogenic pump (11) via a vacuum pipeline (23); The Roots pump assembly comprises a first Roots pump (2) and a second Roots pump (5), one end of the first Roots pump (2) being connected to the first mechanical pump (1) via a vacuum pipeline (23), the other end of the first Roots pump (2) being connected to the first molecular pump (17), the second molecular pump (18), the third molecular pump (8) and the fourth molecular pump (9) via a vacuum pipeline (23), one end of the second Roots pump (5) being connected to the second mechanical pump (4) via a vacuum pipeline (23), and the other end of the second Roots pump (5) being connected to the first cryogenic pump (19), the second cryogenic pump (20), the third cryogenic pump (10) and the fourth cryogenic pump (11) via a vacuum pipeline (23); The first resistance gauge comprises a first sub-resistance gauge (13) and a second sub-resistance gauge (15), the first sub-resistance gauge (13) being connected in parallel with a first cold cathode ionization gauge (14), and the second sub-resistance gauge (15) being connected in parallel with a second cold cathode ionization gauge (16); The second resistance gauge comprises a third sub-resistance gauge (3) and a fourth sub-resistance gauge (6), the third sub-resistance gauge (3) being arranged between the first Roots pump (2) and the first molecular pump (17), the second molecular pump (18), the third molecular pump (8) and the fourth molecular pump (9), and the fourth sub-resistance gauge (6) being arranged between the second Roots pump (5) and the first cryogenic pump (19), the second cryogenic pump (20), the third cryogenic pump (10) and the fourth cryogenic pump (11); The pneumatic gate valve comprises a first gate valve (36), a second gate valve (37), a third gate valve (38), a fourth gate valve (39), a fifth gate valve (29), a sixth gate valve (30), a seventh gate valve (31), and an eighth gate valve (32); the first gate valve (36) is arranged between the ion generating device (12) and the first molecular pump (17), the second gate valve (37) is arranged between the ion generating device (12) and the second molecular pump (18), and the third gate valve (38) is arranged between the ion generating device (12) and the first cryogenic pump (1 9), the fourth gate valve (39) is arranged between the ion generating device (12) and the second cryopump (20), the fifth gate valve (29) is arranged between the ion generating device (12) and the third molecular pump (8), the sixth gate valve (30) is arranged between the ion generating device (12) and the fourth molecular pump (9), the seventh gate valve (31) is arranged between the ion generating device (12) and the third cryopump (10), and the eighth gate valve (32) is arranged between the ion generating device (12) and the fourth cryopump (11); The pneumatic flapper valve comprises a first flapper valve (24), a second flapper valve (25), a third flapper valve (26), a fourth flapper valve (35), a fifth flapper valve (40), a sixth flapper valve (41), a seventh flapper valve (27), and an eighth flapper valve (28), wherein the first flapper valve (24) is arranged between the first Roots pump (2) and the third sub-resistance gauge (3), the second flapper valve (25) is arranged between the second Roots pump (5) and the fourth sub-resistance gauge (6), and the third flapper valve (26) is arranged between the third sub-resistance gauge (3) and the fourth sub-resistance gauge (6). The fourth baffle valve (35) is arranged between the third sub-resistance gauge (3) and the ion generating device (12), the fifth baffle valve (40) is arranged between the first cryogenic pump (19) and the fourth sub-resistance gauge (6), the sixth baffle valve (41) is arranged between the second cryogenic pump (20) and the fourth sub-resistance gauge (6), the seventh baffle valve (27) is arranged between the third cryogenic pump (10) and the fourth sub-resistance gauge (6), and the eighth baffle valve (28) is arranged between the fourth cryogenic pump (11) and the fourth sub-resistance gauge (6).

5. The vacuum system for a compact high-magnetic field ion generator according to claim 1, characterized in that: It also comprises a nitrogen source (22), the nitrogen source (22) being connected to the ion generating device (12) and being used to fill the ion generating device (12) with nitrogen to break the vacuum of the ion generating device (12).

6. The vacuum system for a compact high-magnetic field ion generator according to claim 5, characterized in that: The pneumatic flapper valve further comprises a ninth flapper valve (33) and a tenth flapper valve (34), wherein the ninth flapper valve (33) is arranged between the nitrogen source (22) and the ion generating device (12), and the tenth flapper valve (34) is arranged between the ninth flapper valve (33) and the ion generating device (12).

7. The vacuum system for a compact high-magnetic field ion generator according to claim 4, characterized in that: The invention also comprises a first compressor (21) and a second compressor (7), wherein the first compressor (21) is connected to the first cryopump (19) and the second cryopump (20), and the second compressor (7) is connected to the third cryopump (10) and the fourth cryopump (11).

8. The vacuum system for a compact high-magnetic field ion generator according to claim 7, characterized in that: The vacuum control device is configured to control cryopump regeneration, comprising: Controlling closing of the third gate valve (38), the fourth gate valve (39), the seventh gate valve (31), the eighth gate valve (32), the first compressor (21) and the second compressor (7), and starting the second mechanical pump (4) and the second Roots pump (5); Controlling the first cryopump (19), the second cryopump (20), the third cryopump (10) and the fourth cryopump (11) to start a heating mode, and when the first cryopump (19), the second cryopump (20), the third cryopump (10) and the fourth cryopump (11) are heated to a temperature not less than a first temperature threshold, controlling the opening of the fifth damper valve (40), the sixth damper valve (41), the seventh damper valve (27) and the eighth damper valve (28); When the second vacuum degree measured by the fourth sub-resistance gauge (6) is not less than the first preset vacuum degree, controlling the second baffle valve (25) to open; When the first cryopump (19), the second cryopump (20), the third cryopump (10) and the fourth cryopump (11) are heated to a second temperature threshold, controlling the heating mode to be turned off; When the second vacuum degree measured by the fourth sub-resistance gauge (6) is less than the second preset vacuum degree, controlling the second baffle valve (25) to close; If the second vacuum degree measured by the fourth sub-resistance gauge (6) increases by more than a first preset increase value, controlling the first cryopump (19), the second cryopump (20), the third cryopump (10) and the fourth cryopump (11) to start a heating mode until the second vacuum degree measured by the fourth sub-resistance gauge (6) is less than a second preset vacuum degree; If the second vacuum degree rise measured by the fourth sub-resistance gauge (6) is not greater than the first preset rise value, the first compressor (21) and the second compressor (7) are controlled to be turned on to cool down the first cryogenic pump (19), the second cryogenic pump (20), the third cryogenic pump (10) and the fourth cryogenic pump (11), and the fifth baffle valve (40), the sixth baffle valve (41), the seventh baffle valve (27) and the eighth baffle valve (28) are controlled to be closed.

9. The vacuum system for a compact high-magnetic field ion generator according to claim 8, characterized in that: When the first vacuum degree of the ion generating device (12) is greater than the maximum preset vacuum degree, the vacuum control device is configured to: Controlling the opening of the first mechanical pump (1), the first flapper valve (24), and the fourth flapper valve (35); When the first vacuum degree of the ion generating device (12) is not greater than the maximum preset vacuum degree, controlling to start the first Roots pump (2); When the first vacuum degree of the ion generating device (12) is not greater than the minimum preset vacuum degree, the first gate valve (36), the second gate valve (37), the fifth gate valve (29), and the sixth gate valve (30) are controlled to be opened, and the fourth baffle valve (35) is controlled to be closed; Controlling the start of the first molecular pump (17), the second molecular pump (18), the third molecular pump (8) and the fourth molecular pump (9); When the first vacuum degree of the ion generating device (12) is not greater than the target vacuum degree, and the secondary cold head temperatures of the first cryogenic pump (19), the second cryogenic pump (20), the third cryogenic pump (10) and the fourth cryogenic pump (11) are all not greater than the preset secondary cold head temperature, the third gate valve (38), the fourth gate valve (39), the seventh gate valve (31) and the eighth gate valve (32) are controlled to open.

10. The vacuum system for a compact high-magnetic field ion generator according to claim 9, characterized in that: When the first vacuum degree of the ion generating device (12) is not greater than a maximum preset vacuum degree and greater than a minimum preset vacuum degree, the vacuum control device is configured as follows: Controlling the opening of the first mechanical pump (1), the first Roots pump (2), the first baffle valve (24), and the fourth baffle valve (35); When the first vacuum degree of the ion generating device (12) is not greater than the minimum preset vacuum degree, the first gate valve (36), the second gate valve (37), the fifth gate valve (29) and the sixth gate valve (30) are controlled to be opened, and the fourth baffle valve (35) is controlled to be closed; Controlling the start of the first molecular pump (17), the second molecular pump (18), the third molecular pump (8) and the fourth molecular pump (9); When the first vacuum degree of the ion generating device (12) is not greater than the target vacuum degree, and the secondary cold head temperatures of the first cryogenic pump (19), the second cryogenic pump (20), the third cryogenic pump (10) and the fourth cryogenic pump (11) are all not greater than the preset secondary cold head temperature, the third gate valve (38), the fourth gate valve (39), the seventh gate valve (31) and the eighth gate valve (32) are controlled to open.

11. The vacuum system for a compact high-magnetic field ion generator according to claim 10, characterized in that: When the first vacuum degree of the ion generating device (12) is not greater than the minimum preset vacuum degree, the vacuum control device is configured to: Controlling the opening of the first mechanical pump (1), the first Roots pump (2), and the first baffle valve (24); Controlling the start of the first molecular pump (17), the second molecular pump (18), the third molecular pump (8) and the fourth molecular pump (9); Controlling the opening of the first gate valve (36), the second gate valve (37), the fifth gate valve (29) and the sixth gate valve (30); When the first vacuum degree of the ion generating device (12) is not greater than the target vacuum degree, and the secondary cold head temperatures of the first cryogenic pump (19), the second cryogenic pump (20), the third cryogenic pump (10) and the fourth cryogenic pump (11) are all not greater than the preset secondary cold head temperature, the third gate valve (38), the fourth gate valve (39), the seventh gate valve (31) and the eighth gate valve (32) are controlled to open.

12. The vacuum system for a compact high-magnetic field ion generator according to claim 11, characterized in that: The vacuum control device is configured to control the ion generating device (12) to break the vacuum, comprising: Controlling to open the ninth flapper valve (33); When the first vacuum degree of the ion generating device (12) is greater than a preset vacuum breaking degree, controlling the ninth baffle valve (33) to close; Controlling to open the tenth flapper valve (34); After a preset vacuum breaking time interval, the tenth flapper valve (34) is controlled to close.

13. The vacuum system for a compact high-magnetic field ion generator according to claim 12, characterized in that: The vacuum control device is configured to control the shutdown of a vacuum system for a compact high-magnetic-field ion generating device (12), comprising: Controlling to sequentially close the first gate valve (36), the second gate valve (37), the third gate valve (38), the fourth gate valve (39), the fifth gate valve (29), the sixth gate valve (30), the seventh gate valve (31), the eighth gate valve (32), the first molecular pump (17), the second molecular pump (18), the third molecular pump (8), the fourth molecular pump (9), the first baffle valve (24), the first Roots pump (2), and the first mechanical pump (1).

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