A low-energy DC high-voltage electron accelerator

Abstract

The invention discloses a low-energy direct current high-voltage electron accelerator, comprising a steel cylinder assembly, a filament power supply, an electron gun, a high-voltage assembly and an accelerating tube assembly arranged in combination with the steel cylinder assembly, the filament power supply supplies energy to the electron gun, the high-voltage assembly has a layered voltage multiplier stage connected to the voltage divider stage of the accelerating tube assembly, the accelerating tube assembly is connected to a scanning box through a vacuum pipe, a vacuum pump assembly is arranged on the side of the scanning box to construct a high vacuum environment for electron beam emission, and a gathering coil is arranged on the lower half of the scanning box to gather part of the divergent beam flow for use. The low-energy direct current high-voltage electron accelerator has a small size, low cost, high power conversion rate, stable and reliable operation, and convenient maintenance.

Description

Technical Field

[0001] The present invention relates to the technical field related to electron accelerators, and more precisely to a low-energy direct current high-voltage electron accelerator. Background Art

[0002] An electron accelerator is an electromagnetic device that uses artificial methods to accelerate electrons in a vacuum under the influence of magnetic and electric forces to reach high energy. The application field of electron accelerators is very wide, but except for a few large and high-end electron accelerators used as scientific research tools in the field of basic scientific research, a large number of small and medium-sized accelerators are application-oriented accelerators. Among them, industrial irradiation electron accelerators refer to an electron acceleration device used for irradiating various materials, participating in chemical reactions, and performing industrial production processes such as sterilization and disinfection. The more widely used industrial irradiation electron accelerators include high-frequency and high-voltage electron accelerators and resonant transformer electron accelerators. The above two models have many advantages in medium energy and large beam power, but in the low energy segment (below 500keV), because a power supply system such as a high-power high-frequency power supply or a medium-frequency generator is required to power the accelerator's internal rectifier and voltage multiplier system, the internal structure of the electron accelerator is relatively complex, the volume is large, and there are disadvantages such as low working efficiency in the low energy segment, difficult maintenance, not conducive to miniaturization, and high manufacturing cost. In summary, this field needs an electron accelerator with high working efficiency in the low energy segment, stable operation, small size, and low cost. Summary of the invention

[0003] In view of this, the main purpose of the present invention is to provide a low-energy DC high-voltage electron accelerator, including a steel cylinder assembly, a filament power supply, an electron gun, a high-voltage assembly and an accelerating tube assembly arranged in combination with the steel cylinder assembly, the filament power supply supplies energy to the electron gun, the high-voltage assembly has a layered voltage multiplication stage respectively connected to the voltage division stage of the accelerating tube assembly, the accelerating tube assembly is connected to a scanning box through a vacuum pipe fitting, a vacuum pump assembly is arranged on the side of the scanning box to construct a high vacuum environment for electron beam emission, and a gathering coil is arranged on the lower half of the scanning box to gather part of the divergent beam for utilization.

[0004] In order to achieve the above-mentioned purpose, the present invention provides a low-energy direct current high-voltage electron accelerator, comprising a steel cylinder assembly, a filament power supply, an electron gun, a high-voltage assembly, an accelerating tube assembly, a vacuum pipe fitting, a vacuum pump assembly, a gathering coil and a scanning box, wherein the steel cylinder assembly is a sealed pressure-resistant container, the filament power supply and the electron gun are installed inside the steel cylinder assembly, the high-voltage assembly is installed in combination with the steel cylinder assembly and is installed at the bottom of the steel cylinder assembly, the accelerating tube assembly passes through the bottom flange of the steel cylinder assembly and is connected to the vacuum pipe fitting, and the end of the vacuum pipe fitting away from the accelerating tube assembly is connected to the scanning box; the lower half of the scanning box assembly is combined with a gathering coil; the side of the scanning box is combined with a vacuum pump assembly, the electron gun is connected to the filament power supply, the electron gun is arranged at the end of the accelerating tube assembly, and the high-voltage assembly is combined with the accelerating tube assembly.

[0005] Preferably, the high-voltage assembly includes a high-voltage module, a conical high-voltage equalizing cap and an external control power supply. The high-voltage module and the conical high-voltage equalizing cap are installed inside the steel cylinder assembly. The high-voltage module is combined with the accelerating tube assembly. The conical high-voltage equalizing cap is installed on the top of the high-voltage assembly and connected to one end of the accelerating tube assembly facing the electron gun. The external control power supply is arranged outside the steel cylinder assembly and is connected to the high-voltage module and the filament power supply through a cable.

[0006] Preferably, the accelerating tube assembly has a plurality of voltage-dividing stages, the high-voltage module has a plurality of layered voltage-doubling stages, and the layered voltage-doubling stages of the high-voltage module are connected to the voltage-dividing stages of the accelerating tube assembly in a one-to-one correspondence.

[0007] Preferably, the steel cylinder assembly includes a cylinder body, a top cover and a bottom flange, and the top cover and the bottom flange are detachably connected to the two ends of the cylinder body respectively; the steel cylinder assembly is a pressure-resistant container, which can be filled with insulating gas of a certain pressure, and a detection device is installed on the cylinder body.

[0008] Preferably, the detection device 1 is one or more of a pressure gauge, a pressure sensor, and a safety valve.

[0009] Preferably, a cooling water channel is provided in the side wall of the cylinder, and two cooling water inlets and outlets are respectively provided at the top and bottom ends of the side wall of the cylinder, and the two cooling water inlets and outlets are connected to the cooling water channel.

[0010] Preferably, a focusing coil is mounted on the vacuum tube.

[0011] Preferably, a beam scanning device is provided at one end of the scanning box connected to the vacuum tube.

[0012] Preferably, gathering coils are arranged on both sides of the end surface of the scanning box away from the vacuum tube.

[0013] Preferably, the vacuum pump assembly includes a mechanical pump, a molecular pump, an ion pump, a plug-in valve and a vacuum detection unit. One side of the scanning box is connected to the ion pump, and the other side of the scanning box is connected to the plug-in valve, the vacuum detection unit, the molecular pump and the mechanical pump in sequence.

[0014] Compared with the prior art, the advantages of the low-energy DC high-voltage electron accelerator disclosed in the present invention are: a built-in high-voltage component is used to use a full-wave rectifier circuit to double the voltage and boost the voltage, and each voltage doubler is connected to the voltage divider of the accelerating tube to deal with the voltage division and shielding problems of the accelerating tube, which greatly reduces the structural difficulty of the high-voltage component, reduces the volume and cost, is conducive to the miniaturization of the accelerator, greatly improves the power conversion rate, works stably and reliably, and is easy to repair; and the focusing coil technology is used to gather about 15% of the scattered and unusable beams for use, which greatly improves the beam utilization rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 Shown is a cross-sectional view of a low-energy DC high-voltage electron accelerator of the present invention.

[0017] Figure 2 Shown is a partial cross-sectional view of a low-energy DC high-voltage electron accelerator of the present invention.

[0018] Figure 3 Shown is a schematic structural diagram of a vacuum pump assembly of a low-energy DC high-voltage electron accelerator of the present invention. DETAILED DESCRIPTION

[0019] like Figure 1As shown, a low-energy DC high-voltage electron accelerator of the present invention comprises a steel cylinder assembly 10, a filament power supply 21, an electron gun 22, a high-voltage assembly 23, an accelerating tube assembly 24, a vacuum pipe fitting 30 and a scanning box 40. The steel cylinder assembly 10 is a sealed pressure-resistant container, the filament power supply 21 and the electron gun 22 are installed inside the steel cylinder assembly 10, the high-voltage assembly 23 is installed in combination with the steel cylinder assembly 10, the accelerating tube assembly 24 passes through the bottom flange of the steel cylinder assembly 10 and is connected to the vacuum pipe fitting 30, and the end of the vacuum pipe fitting 30 away from the accelerating tube assembly 24 is connected to the scanning box 40. Figure 3 It can be seen that a vacuum pump assembly 50 is installed on the side of the scanning box 40 to construct a high vacuum environment for the electron beam. The electron gun 22 is connected to the filament power supply 21, and the filament power supply 21 supplies power to the electron gun 22. The filament power supply 21 provides the power required by the filament of the electron gun 22. The electron gun 22 is arranged on the top of the accelerating tube assembly 24. The high voltage assembly 23 is arranged in combination with the accelerating tube assembly 24.

[0020] A focusing coil 31 is mounted on the vacuum tube 30 to adjust the diameter of the beam spot. The bottom surface of the scanning box 40 away from the vacuum tube 30 is sealed with a vacuum sealing titanium foil 43. A beam scanning device 41 is arranged at one end of the scanning box 40 connected to the vacuum tube 30, which is used to sweep the beam point into a strip-shaped beam, which enters the scanning box 40 and then passes through the sealing titanium foil 43 to be emitted onto the irradiated product. Gathering coils 42 are arranged on both sides of the end surface of the scanning box 40 away from the vacuum tube 30, which are used to gather the scattered beam into a beam that is perpendicular to the end surface of the scanning box 40. By setting the gathering coil 42, about 15% of the scattered beam that cannot be used can be gathered and utilized, which greatly improves the beam utilization rate.

[0021] The steel cylinder assembly 10 includes a cylinder 11, a top cover 12 and a bottom flange 13, and the top cover 12 and the bottom flange 13 are detachably connected to the two ends of the cylinder 11 respectively. The interior of the steel cylinder assembly 10 can be filled with insulating gas of a certain pressure. Accordingly, a detection device 111 is installed in combination with the cylinder 11, and the detection device 111 can be one or more of a pressure gauge, a pressure sensor, and a safety valve. Furthermore, a safety valve 121 can be installed in combination with the top cover 12. The insulating gas is preferably a mixture of sulfur hexafluoride or nitrogen and carbon dioxide.

[0022] For cooling purposes, a cooling water channel 114 is opened in the side wall of the cylinder 11, and two cooling water inlets and outlets 112 and 113 are respectively opened at the top and bottom ends of the side wall of the cylinder 11. The two cooling water inlets and outlets 112 and 113 are connected to the cooling water channel 114, and are respectively connected to the cooling water inlet and outlet pipes to cool the steel cylinder assembly 10.

[0023] like Figure 2 As shown, the high-voltage assembly 23 includes a high-voltage module 231, a conical high-voltage equalizing cap 232 and an external control power supply 233. The high-voltage module 231 and the conical high-voltage equalizing cap 232 are both installed inside the steel cylinder assembly 10. The high-voltage module 231 is combined with the accelerating tube assembly 24. The conical high-voltage equalizing cap 232 is installed on the top of the high-voltage module 231 and connected to one end of the accelerating tube assembly 24 facing the electron gun 22. The external control power supply 233 is arranged outside the steel cylinder assembly 10. The external control power supply 233 is connected to the high-voltage module 231 and the filament power supply 21. The accelerating tube assembly 24 has a plurality of voltage division stages, and the high-voltage module 231 has a plurality of layered voltage multiplication stages. The layered voltage multiplication stages of the high-voltage module 231 are connected to the voltage division stages of the accelerating tube assembly 24 in a one-to-one correspondence, so that the voltage division is more uniform, and the inter-stage shielding problem of the accelerating tube is avoided. The high voltage after voltage doubling is concentrated on the conical high voltage equalizing cap 232, and both the high voltage and the filament voltage are controlled by the external control power supply 233, which is convenient for adjustment and maintenance.

[0024] like Figure 3 As shown, the vacuum pump assembly 50 includes a mechanical pump 51, a molecular pump 52, an ion pump 53, a plug-in valve 54 and a vacuum detection unit 55. One side of the scanning box 40 is connected to the ion pump 53, and the other side of the scanning box 40 is connected to the plug-in valve 54, the vacuum detection unit 55, the molecular pump 52 and the mechanical pump 51 in sequence. After the molecular pump 52 and the mechanical pump 51 are used to establish a vacuum, after the vacuum detection unit 55 detects, the plug-in valve 54 is plugged in, and the ion pump 53 can be used alone to maintain the vacuum state of the acceleration tube assembly 24, the vacuum pipe 30, the scanning box 40, etc.

[0025] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A low-energy DC high-voltage electron accelerator, characterized in that: It comprises a steel cylinder assembly, a filament power supply, an electron gun, a high-voltage assembly, an accelerating tube assembly, a vacuum pipe fitting, a vacuum pump assembly, a gathering coil and a scanning box. The steel cylinder assembly is a sealed pressure-resistant container. The filament power supply, the electron gun and the high-voltage assembly are installed inside the steel cylinder assembly. The high-voltage assembly is installed in combination with the steel cylinder assembly and is installed at the bottom of the steel cylinder assembly. The accelerating tube assembly passes through the bottom flange of the steel cylinder assembly and is connected to the vacuum pipe fitting. The end of the vacuum pipe fitting away from the accelerating tube assembly is connected to the scanning box. The gathering coil is installed in combination with the lower half of the scanning box assembly. The vacuum pump assembly is installed in combination with the side of the scanning box. The electron gun is connected to the filament power supply. The electron gun is arranged at the end of the accelerating tube assembly. The high-voltage assembly is arranged in combination with the accelerating tube assembly. The high-voltage assembly includes a high-voltage module, a conical high-voltage equalizing cap and an external control power supply. The high-voltage module and the conical high-voltage equalizing cap are installed inside the steel cylinder assembly. The high-voltage module is combined with the accelerating tube assembly. The conical high-voltage equalizing cap is installed on the top of the high-voltage assembly and connected to one end of the accelerating tube assembly facing the electron gun. The external control power supply is arranged outside the steel cylinder assembly and is connected to the high-voltage module and the filament power supply through a cable; a beam scanning device is arranged at the end of the scanning box connected to the vacuum tube.

2. The low-energy DC high-voltage electron accelerator according to claim 1, characterized in that: The accelerating tube assembly has a plurality of voltage division stages, and the high-voltage module has a plurality of layered voltage multiplication stages. The layered voltage multiplication stages of the high-voltage module are connected to the voltage division stages of the accelerating tube assembly in a one-to-one correspondence.

3. The low-energy DC high-voltage electron accelerator according to claim 1, characterized in that: The steel cylinder assembly includes a cylinder body, a top cover and a bottom flange, and the top cover and the bottom flange are detachably connected to the two ends of the cylinder body respectively; the steel cylinder assembly is a pressure-resistant container, and an insulating gas of a certain pressure can be filled inside, and a detection device is installed on the cylinder body.

4. The low-energy DC high-voltage electron accelerator according to claim 3, characterized in that: The detection device is one or more of a pressure gauge, a pressure sensor, and a safety valve.

5. The low-energy DC high-voltage electron accelerator according to claim 3, characterized in that: A cooling water channel is provided in the side wall of the cylinder, and two cooling water inlets and outlets are respectively provided at the top and bottom ends of the side wall of the cylinder, and the two cooling water inlets and outlets are communicated with the cooling water channel.

6. The low-energy DC high-voltage electron accelerator according to claim 1, characterized in that: A focusing coil is mounted on the vacuum tube.

7. The low-energy DC high-voltage electron accelerator according to claim 1, characterized in that: The gathering coils are arranged on both sides of the end surface of the scanning box away from the vacuum tube.

8. The low-energy DC high-voltage electron accelerator according to claim 1, characterized in that: The vacuum pump assembly includes a mechanical pump, a molecular pump, an ion pump, a plug-in valve and a vacuum detection unit. One side of the scanning box is connected to the ion pump, and the other side of the scanning box is connected to the plug-in valve, the vacuum detection unit, the molecular pump and the mechanical pump in sequence.

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