Magnetic cutting module and electron gun device

Abstract

The present invention discloses a magnetic field shear module and an electron gun device, relating to the technical field of electron guns. Among them, the electron gun includes a cathode and an anode, and the magnetic field shear module includes a main coil, an auxiliary coil, a cathode coil, a first pole shoe, and a second pole shoe; the main coil is arranged corresponding to the anode of the electron gun, the auxiliary coil is arranged corresponding to the junction of the anode and the cathode of the electron gun, the cathode of the auxiliary coil is connected to the anode of the main coil through the first pole shoe, the cathode coil is arranged corresponding to the cathode of the electron gun, and the anode of the cathode coil is connected to the anode of the auxiliary coil through the second pole shoe; wherein, the main coil, the auxiliary coil, and the cathode coil respectively generate a first magnetic field, a second magnetic field, and a third magnetic field, the first magnetic field is less than the second magnetic field, the third magnetic field is opposite to the directions of the first magnetic field and the second magnetic field, and one end of the first pole shoe faces the junction of the anode and the cathode of the electron gun. The magnetic field shear module provided by the present invention aims to improve the stability of the large cyclotron electron beam emitted by the electron gun.

Description

Technical Field

[0001] The present invention relates to the technical field of electron guns, and particularly to a magnetic cusp module and an electron gun device. Background Art

[0002] An electron gun device is used to emit an electron beam. The generation of a traditional large-cyclotron electron beam depends on a magnetic field reversal technique. When the electron beam passes through a reversed magnetic field, most of its energy is converted from longitudinal motion to rotational motion, thereby forming a hollow large-cyclotron electron beam. Ideally, a linearly moving electron beam can be transformed into a large-cyclotron electron beam with the same initial radius after passing through a stepwise reversed magnetic field. However, in practical applications, due to the difficulty in achieving an ideal stepwise reversed magnetic field, the electron beam often deviates from the rotational symmetry axis when passing through the transition section, resulting in a ripple phenomenon. Therefore, the traditional electron gun device has a problem of poor stability. Summary of the Invention

[0003] The present invention provides a magnetic cusp module and an electron gun device, aiming to improve the stability of the large-cyclotron electron beam emitted by the electron gun.

[0004] To achieve the above object, the magnetic cusp module provided by the present invention is used for an electron gun, and the electron gun includes a cathode and an anode. The magnetic cusp module includes:

[0005] A main coil, which is arranged corresponding to the anode of the electron gun, and the main coil is used to generate a first magnetic field;

[0006] An auxiliary coil, which is arranged corresponding to the junction of the anode and the cathode of the electron gun. The cathode of the auxiliary coil is connected to the anode of the main coil through a first pole piece. The auxiliary coil is used to generate a second magnetic field. The direction of the first magnetic field is the same as that of the second magnetic field, and the intensity of the first magnetic field is less than that of the second magnetic field;

[0007] One end of the first pole piece faces the junction of the anode and the cathode of the electron gun, so as to guide the first magnetic field and the second magnetic field to the junction;

[0008] A cathode coil, which is arranged corresponding to the cathode of the electron gun. The anode of the cathode coil is connected to the anode of the auxiliary coil through a second pole piece. The cathode coil is used to generate a third magnetic field. The direction of the third magnetic field is opposite to that of the first magnetic field and the second magnetic field, and the intensity of the third magnetic field is less than that of the first magnetic field.

[0009] In one embodiment, the magnetic cusp module further includes a housing, and the housing includes:

[0010] A cover shell, the cover shell having a receiving cavity, and the main coil, the auxiliary coil, and the cathode coil are all disposed in the receiving cavity;

[0011] A bottom plate, the bottom plate being sealed to the receiving cavity of the cover shell, and the bottom plate being made of a non-magnetic material.

[0012] In one embodiment, the cover shell is made of a magnetic material, and the first pole shoe and the second pole shoe are made of a magnetic material;

[0013] One end of the first pole shoe and the second pole shoe is connected to the cover shell, and the other end of the first pole shoe and the second pole shoe passes through the bottom plate and faces the electron gun.

[0014] In one embodiment, the first pole shoe includes:

[0015] A connecting section, the connecting section being disposed between the main coil and the auxiliary coil, and the first end of the connecting section is connected to the cover shell, and the second end of the connecting section passes through the bottom plate;

[0016] A magnetic conducting section, the magnetic conducting section being connected to the second end of the connecting section, and the magnetic conducting section faces the junction of the anode and the cathode of the electron gun to guide the magnetic field generated by the main coil and the auxiliary coil to the junction;

[0017] The connecting section and the magnetic conducting section are arranged at an angle.

[0018] In one embodiment, the first end of the second pole shoe is connected to the cover shell, the second pole shoe passes through the bottom plate and faces the cathode of the electron gun.

[0019] In one embodiment, the main coil has a first current access end, and when the main coil accesses a first current through the first current access end, a first magnetic field is generated at the anode of the electron gun;

[0020] The auxiliary coil has a second current access end, and when the auxiliary coil accesses a second current through the second current access end, a second magnetic field is generated at the junction of the anode and the cathode of the electron gun;

[0021] The cathode coil has a third current access end, and when the cathode coil accesses a third current through the third current access end, a third magnetic field is generated at the cathode of the electron gun.

[0022] In one embodiment, the second current is greater than the first current, and the third current is less than the first current and the second current.

[0023] In one embodiment, the coil diameter of the main coil is larger than the coil diameters of the auxiliary coil and the cathode coil.

[0024] In one embodiment, the length of the main coil is greater than the length of the auxiliary coil.

[0025] The present invention also provides an electron gun device, which includes:

[0026] an electron gun; and

[0027] at least two magnetic cusp modules as described in any one of the above, and the two magnetic cusp modules are oppositely arranged on both sides of the electron gun.

[0028] Beneficial effects:

[0029] 1. The magnetic cusp module includes a main coil, an auxiliary coil, and a cathode coil; the main coil is used to provide a first magnetic field for the electron beam according to the magnetic field requirements of the high-frequency circuit in the gyrotron; the auxiliary coil provides a second magnetic field for the electron beam, where the intensity of the first magnetic field is less than the intensity of the second magnetic field; the cathode coil provides a third magnetic field, and the direction of the third magnetic field is opposite to those of the first magnetic field and the second magnetic field. Thus, when the electron beam moves from the third magnetic field to the second magnetic field, due to the opposite directions of the two magnetic fields, the electron beam will flip to form a large gyration electron beam; at this time, since the second magnetic field is greater than the first magnetic field, that is, there is a greater magnetic field intensity in the second magnetic field after inversion, a greater radial force is provided for the electron beam. According to the principle that the integral of the radial force over the transition length (referring to the transition of magnetic field inversion) is equal to the radial force provided by the ideal cusp magnetic field, the electron beam ripple can be reduced or even eliminated.

[0030] 2. One end of the first pole shoe faces the junction of the anode and the cathode of the electron gun, so as to guide the first magnetic field and the second magnetic field to the junction. It should be noted that by guiding the first magnetic field and the second magnetic field to the junction of the anode and the cathode of the electron gun, the control ability of the auxiliary coil on the movement trajectory of the electron beam is enhanced. Specifically, in the electron gun, the junction of the anode and the cathode is the place where the electron beam is formed and starts to accelerate. If the magnetic field distribution can be precisely controlled in this area, the initial direction of the electron beam can be more effectively affected, thereby optimizing its subsequent movement trajectory. Therefore, the first pole shoe realizes the control of the initial direction, which is beneficial to controlling the movement trajectory, and further reduces the occurrence of deviation and electron beam ripple.

[0031] 3. The intensity of the third magnetic field is less than that of the first magnetic field. In this case, since the intensity of the second magnetic field is greater than that of the first magnetic field, it can be concluded that the second magnetic field is also greater than the third magnetic field. Since the field intensity is not equal before and after flipping the magnetic field (the magnetic field becomes larger after flipping from small), precise control of the electron beam path can be achieved. During this process, in the transition stage of the electron beam from emission to entering the main coil region, the reversed magnetic field can effectively compress it and reduce the divergence phenomenon, making it more compact and orderly, while reducing the ripple degree. Therefore, this solution helps to compress the electron beam and reduce the ripple of the large gyrotron electron beam, improving the overall quality and stability of the electron beam. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the structures shown in these drawings.

[0033] Figure 1 Schematic diagram of the structure of an embodiment of the electron gun device provided by the present invention;

[0034] Figure 2 Schematic diagram of the structure of an embodiment of the magnetic mirror module provided by the present invention;

[0035] Figure 3 Schematic diagram of an embodiment of the magnetic field flipping of the magnetic mirror module provided by the present invention;

[0036] Figure 4 Schematic diagram of an embodiment of the movement trajectory of the electron beam based on this magnetic mirror module;

[0037] Figure 5 Schematic diagram of the flipping magnetic field under ideal conditions;

[0038] Figure 6 For Figure 5 Schematic diagram of the movement trajectory of the electron beam formed by the corresponding flipping magnetic field;

[0039] Figure 7 Magnetic mirror module in the prior art;

[0040] Figure 8 For Figure 7 Schematic diagram of the flipping magnetic field of the magnetic mirror module;

[0041] Figure 9 For Figure 8 Schematic diagram of the movement trajectory of the electron beam formed by the corresponding flipping magnetic field.

[0042] Description of the reference numerals in the drawings:

[0043] 10. Magnetic shear module; 100. Main coil; 200. Auxiliary coil; 300. Cathode coil; 400. Housing; 410. Cover shell; 420. Bottom plate; 500. First pole shoe; 510. Connection section; 520. Magnetic conduction section; 600. Second pole shoe;

[0044] 20. Electron gun device; 700. Electron gun; 710. Anode hole.

[0045] The realization, functional features and advantages of the object of the present invention will be further described with reference to the embodiments and the accompanying drawings. Specific embodiments

[0046] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0047] It should be noted that if there are directional indications (such as up, down, left, right, front, back,...) involved in the embodiments of the present invention, the directional indications are only used to explain the relative positional relationship and movement conditions between components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0048] In addition, if there are descriptions such as "first" and "second" involved in the embodiments of the present invention, the descriptions of "first" and "second" are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In addition, if "and / or" or "and / or" appears throughout the text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or a solution where A and B are satisfied simultaneously. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0049] The electron gun device is used to emit an electron beam. The generation of a traditional large-cyclotron electron beam relies on the magnetic field reversal technique. When the electron beam passes through a reversing magnetic field, most of its energy is converted from longitudinal motion to rotational motion, thus forming a hollow large-cyclotron electron beam. Ideally, a linearly moving electron beam can be transformed into a large-cyclotron electron beam with the same initial radius after passing through a stepwise reversing magnetic field. However, in practical applications, due to the difficulty in achieving an ideal stepwise reversing magnetic field, the electron beam often deviates from the rotational symmetry axis when passing through the transition section, resulting in a ripple phenomenon. Therefore, the traditional electron gun device has the problem of poor stability.

[0050] As Figure 1 shown, the present invention proposes a magnetic cusp module 10 and an electron gun device 20, aiming to improve the stability of the large-cyclotron electron beam emitted by the electron gun 700.

[0051] To achieve the above object, the magnetic cusp module 10 proposed by the present invention is used for the electron gun 700. The magnetic cusp module 10 is used to transform the electron beam emitted by the electron gun 700 into a large-cyclotron electron beam and can reduce the ripple phenomenon of the large-cyclotron electron beam to improve the stability of the large-cyclotron electron beam emitted by the electron gun 700.

[0052] In one embodiment, the electron gun 700 includes a cathode and an anode. It can be understood that the cathode, as an electron emission source, usually adopts a high-purity metal material or a hot cathode design, and releases a large number of free electrons through the thermionic emission mechanism under heating conditions. The anode is located in the downstream area of the cathode, and its main function is to provide an accelerating electric field, so that the electrons emitted from the cathode can obtain sufficient kinetic energy under the action of the electric field, thus forming a high-speed moving electron beam.

[0053] In a traditional magnetic cusp module, there are two magnetic fields with opposite directions. Therefore, when the electron beam moves from one magnetic field to another magnetic field, that is, when passing through a reversing (cusp) magnetic field, a hollow large-cyclotron electron beam will be generated, and most of the energy of the electron beam is concentrated in the rotational motion. According to the law of conservation of energy, the energy of the longitudinal motion of the electron beam is continuously transformed into the energy of the longitudinal motion in the reversing magnetic field. Ideally, a beam of electrons initially moving linearly with a radius of R0 will be transformed into a large-cyclotron electron beam with the same helical radius R0 as Figure 5 shown after passing through an ideal stepwise reversing magnetic field as Figure 6 shown. However, in practical applications, as Figure 7 shown, due to technical limitations, there is a gap formed by the pole shoes between the two coils, and the magnetic field reversal often requires a transition section to achieve, which makes it difficult to achieve an ideal stepwise reversal effect. As Figure 8 shown, it is a non-stepwise reversing magnetic field with a short transition section. In the transition section, the electron beam is prone to deviate from the ideal rotational symmetry axis, thus forming a ripple phenomenon. AsFigure 9 As shown, this has an adverse effect on the quality and stability of the large spiral electron beam.

[0054] In one embodiment, as Figure 1 shown, the magnetic cusp module 10 proposed by the present invention includes a main coil 100, an auxiliary coil 200, and a cathode coil 300. The main coil 100 is arranged corresponding to the anode of the electron gun 700, and the main coil 100 is used to generate a first magnetic field; the auxiliary coil 200 is arranged corresponding to the junction of the anode and the cathode of the electron gun 700. The cathode of the auxiliary coil 200 is connected to the anode of the main coil 100 through a first pole shoe 500. The auxiliary coil 200 is used to generate a second magnetic field. The direction of the first magnetic field is the same as the direction of the second magnetic field, and the intensity of the first magnetic field is less than the intensity of the second magnetic field; one end of the first pole shoe 500 faces the junction of the anode and the cathode of the electron gun 700 to guide the first magnetic field and the second magnetic field to the junction; the cathode coil 300 is arranged corresponding to the cathode of the electron gun 700. The anode of the cathode coil 300 is connected to the anode of the auxiliary coil 200 through a second pole shoe 600. The cathode coil 300 is used to generate a third magnetic field, and the direction of the third magnetic field is opposite to the directions of the first magnetic field and the second magnetic field.

[0055] It can be understood that the magnetic field directions of the main coil 100 and the cathode coil 300 are opposite. When the electron beam moves from the area corresponding to the cathode coil 300 to the area corresponding to the main coil 100, it will become a large spiral electron beam. Among them, the main coil 100 is arranged corresponding to the anode of the electron gun 700, and the main coil 100 is used to generate a first magnetic field; the cathode coil 300 is arranged corresponding to the cathode of the electron gun 700, and the cathode coil 300 is used to generate a third magnetic field, and the direction of the third magnetic field is opposite to the direction of the first magnetic field. In this case, a cusp magnetic field is realized. When the electron beam moves from the area where the main coil 100 is located to the area where the cathode coil 300 is located, it will experience a cusp magnetic field composed of these two reverse magnetic fields. This process causes the originally linearly moving electron beam to deflect when passing through this cusp magnetic field, thereby forming a large spiral electron beam.

[0056] It should be noted that, based on the above-mentioned cusp magnetic field, there is also an auxiliary coil 200, which is arranged corresponding to the junction of the anode and the cathode of the electron gun 700 and is used to generate a second magnetic field. Since the auxiliary coil 200 is arranged between the main coil 100 and the cathode coil 300, and the direction of the second magnetic field generated by the auxiliary coil 200 is the same as the direction of the first magnetic field generated by the main coil 100, and the direction of the second magnetic field generated by the auxiliary coil 200 is opposite to the direction of the third magnetic field generated by the cathode coil 300. Therefore, the auxiliary coil 200 and the main coil 100 can be regarded as an integral body. Thus, the cusp magnetic field in this embodiment is actually formed between the auxiliary coil 200 and the cathode coil 300. That is to say, when the electron beam moves from the area corresponding to the cathode coil 300 to the area corresponding to the auxiliary coil 200, it will become a large cyclotron electron beam.

[0057] It should be noted that the magnetic field directions of the auxiliary coil 200 and the main coil 100 are the same, but the intensity of the second magnetic field generated by the auxiliary coil 200 is greater than the intensity of the first magnetic field. In this way, the ripple of the large cyclotron electron beam can be effectively reduced. As Figure 3 shown, the magnetic field intensity of the main coil 100 is B2, while the magnetic field intensity of the auxiliary coil 200 is the small peak value after the magnetic field is flipped, and the corresponding magnetic field intensity is greater than B2. Specifically, due to the relatively large second magnetic field intensity, during the magnetic field flipping process (that is, from the third magnetic field of the cathode coil 300 to the second magnetic field of the auxiliary coil 200), there is a region where the magnetic field intensity increases significantly. This enhanced magnetic field provides a greater radial force for the electron beam. According to the principle that the integral of the radial force over the transition length is equal to the radial force provided by the ideal cusp magnetic field, this enhanced magnetic field (the second magnetic field) can compensate for the uneven energy distribution problem caused by non-ideal factors during the magnetic field flipping process. In practical applications, the magnetic field flipping usually requires a transition section to achieve, and this transition section will cause the electron beam to deviate from the ideal rotation symmetry axis, thus generating ripples. However, by increasing the intensity of the second magnetic field generated by the auxiliary coil 200 and making it reach a higher value in a short time after flipping, an additional radial force can be effectively provided to help the electron beam stabilize to the ideal orbit faster, reducing or even eliminating the ripple phenomenon.

[0058] It should also be noted that since the initial energy of the electron beam near the cathode of the electron gun 700 is very small, slight changes in its geometric shape will greatly change the quality of the large gyrotron electron beam. In contrast, the electron beam that has moved near the anode has already obtained a relatively high energy and is insensitive to the geometric shape of the anode. It is difficult to control the motion state of the electron beam by changing the shape of the anode. Therefore, the optimization of the electrode geometric shape in the traditional design mainly focuses on the cathode region to improve the initial emission characteristics of the electron beam. However, this method has limitations in adjusting the overall motion trajectory of the electron beam. In this embodiment, in order to overcome these limitations and more effectively control the motion trajectory of the electron beam (i.e., effectively reduce the ripple of the electron beam), the first pole shoe 500 is adopted. As Figure 1 shown, one end of the first pole shoe 500 faces the junction of the anode and the cathode of the electron gun 700, so as to guide the first magnetic field and the second magnetic field to the junction, enhancing the control ability of the auxiliary coil 200 on the motion trajectory of the electron beam. It can be understood that in the electron gun 700, the junction of the anode and the cathode is the place where the electron beam is formed and starts to accelerate. If the magnetic field distribution can be precisely controlled in this area, the initial direction of the electron beam can be more effectively affected, thereby optimizing its subsequent motion trajectory. Therefore, the first pole shoe 500 realizes the control of the initial direction, which is beneficial to controlling the motion trajectory, and further reduces the occurrence of deviation and electron beam ripple.

[0059] Optionally, as Figure 1 shown, the second pole shoe 600 extends towards the cathode of the electron gun 700, which can enhance the cusp magnetic field in the electron gun 700, that is, enhance the control effect of the cathode coil 300 and the auxiliary coil 200 on the electron beam. Specifically, the position of the second pole shoe 600 enables it to more effectively guide the reverse magnetic field generated by the cathode coil 300 and the strong magnetic field of the auxiliary coil 200 to the cathode region of the electron gun 700, which is the key position where the electron beam is formed and starts to accelerate. In this way, the second pole shoe 600 not only strengthens the concentration of the magnetic field in this area, but also improves the uniformity and stability of the magnetic field distribution, ensuring that the electron beam travels along the expected path from the beginning. The enhanced cusp magnetic field helps to more precisely control the initial emission state of the electron beam, reduce the deviation and ripple phenomena caused by magnetic field non-uniformity or transition sections, and improve the performance and reliability of the entire magnetic cusp module 10.

[0060] In this embodiment, the materials of the first pole shoe 500 and the second pole shoe 600 are magnetic conductive materials, such as iron, which can be used to guide the magnetic field.

[0061] In addition, the first pole shoe 500 is not only used to control the movement trajectory, but also can effectively separate the main coil 100 and the auxiliary coil 200. The second pole shoe 600 is not only used to separate the auxiliary coil 200 and the cathode coil 300, but also can enhance the control effect of the cathode coil 300 and the auxiliary coil 200 on the electron beam. Thus, it is beneficial to the miniaturized design of the magnetic field cutting module 10.

[0062] It should be noted that the intensity of the third magnetic field is less than that of the first magnetic field. As Figure 3 shown, the intensity of the third magnetic field is B1, and the intensity of the first magnetic field is B2, where B2 is greater than B1. In this case, since the intensity of the second magnetic field is greater than that of the first magnetic field, it can be concluded that the second magnetic field is also greater than the third magnetic field. Since the field strengths before and after the magnetic field flipping are not equal (the magnetic field becomes larger after flipping from small), precise control of the electron beam path can be achieved. During this process, in the transition stage of the electron beam from emission to entering the region of the main coil 100, the reversed magnetic field can effectively compress it and reduce the divergence phenomenon, making it more compact and orderly, while reducing the ripple degree. Therefore, this solution helps to compress the electron beam and reduce the ripple of the large gyrotron electron beam, improving the overall quality and stability of the electron beam.

[0063] Optionally, the magnetic field intensity of the main coil 100 is determined by the high-frequency circuit in the gyrotron traveling-wave tube. The magnetic field intensities of the cathode coil 300 and the auxiliary coil 200 are adjustable, providing greater flexibility for optimizing the quality of the electron beam. The magnetic field of the cathode coil 300 can adjust the ratio of the gyro energy to the longitudinal energy of the electrons according to the law of conservation of electron angular momentum; the magnetic field of the auxiliary coil 200 can be adjusted according to the principle that the integral of the radial force over the transition length is equal to the radial force provided by the ideal magnetic field cutting. In a feasible implementation, the magnetic field intensities of the cathode coil 300 and the auxiliary coil 200 are adjusted to adjust the ratio of the gyro energy to the longitudinal energy of the electron beam to reach a predetermined value (the output power of the gyrotron traveling-wave tube can be observed. The greater the power, the closer the ratio is to the predetermined value; the smaller the power, the more deviated the ratio is from the predetermined value), and to minimize the ripple of the electron beam as much as possible (observe the thickness of the electron beam spot on the fluorescent screen. The greater the thickness, the greater the ripple; the smaller the thickness, the smaller the ripple). Also, the positions and shapes of the first pole shoe 500 and the second pole shoe 600 are adjustable, which can be adjusted for different structures of the electron gun 700 or for different electron beam requirements, to enhance and adjust the magnetic field distribution in the region between the cathode and the anode. For example, by adjusting the angles and positions of the first pole shoe 500 and the second pole shoe 600, the magnetic field distribution in the region between the cathode and the anode can be enhanced and adjusted to ensure that the magnetic field can more effectively guide and control the movement trajectory of the electron beam.

[0064] It should be noted that in this embodiment, the second magnetic field is greater than the first magnetic field, the first magnetic field is greater than the third magnetic field, and the first pole shoe 500 points to the junction of the anode and the cathode of the electron gun 700. All of these three solutions can improve the stability of the electron gun 700. In this embodiment, the three are implemented together, but it does not mean that the three must be implemented together to improve the stability of the electron gun 700. In other embodiments, any one of the three can be implemented alone, or any two of the three can be combined.

[0065] As Figure 3 and Figure 4 shown, the magnetic field intensity of the cathode coil 300 is B1, and the magnetic field intensity of the main coil 100 is -B2. The magnetic field changes from positive to negative, so a reversed magnetic field is formed. The intensity of the auxiliary coil 200 is not marked on the coordinate in the figure, but it can be seen that when the magnetic field changes from B1 to -B2, there is a peak value formed by the auxiliary coil 200. Thus, based on the above principle, a large cyclotron electron beam as Figure 4 shown can be formed. Compared with the existing electron beam (such as Figure 6 and Figure 9 ), this electron beam has smaller ripples and can also be controlled on the corresponding motion trajectory. Therefore, the magnetic field reversal module 10 can improve the stability of the large cyclotron electron beam emitted by the electron gun 700.

[0066] Therefore, in this embodiment, the main coil 100 provides the magnetic field intensity required for the high-frequency circuit in the gyrotron traveling wave tube; the first pole shoe 500 between the auxiliary coil 200 and the main coil 100 guides the magnetic fields generated by the two coils to the junction of the anode and the cathode of the electron gun 700, enhancing the control effect of the auxiliary coil 200 on the motion trajectory of the electron beam; the polarity of the auxiliary coil 200 is the same as the magnetic field direction of the main coil 100, and the corresponding magnetic field intensity can be set to control the magnetic field distribution near the anode; the magnetic field direction of the cathode coil 300 is opposite to that of the auxiliary coil 200, and the distribution of the reversed magnetic field is controlled by changing the current. The magnetic field reversal of the magnetic field reversal module 10 has a short transition section, which can reduce the electron beam ripples; in addition, there is a short section with a larger magnetic field intensity after the magnetic field reversal, which provides a greater radial force for the electron beam. According to the principle that the integral of the radial force over the transition length is equal to the radial force provided by the ideal reversed magnetic field, the electron beam ripples can be reduced or even eliminated.

[0067] In one embodiment, as Figure 2 shown, the magnetic field reversal module 10 further includes a housing 400, and the housing 400 includes a cover shell 410 and a bottom plate 420. The cover shell 410 has a receiving cavity, and the main coil 100, the auxiliary coil 200, and the cathode coil 300 are all disposed in the receiving cavity; the bottom plate 420 seals the receiving cavity of the cover shell 410, and the bottom plate 420 is made of non-magnetic material.

[0068] In this embodiment, the magnetic cutting module 10 includes a housing 400 composed of a cover shell 410 and a bottom plate 420, which is designed to provide physical protection for internal components and optimize the magnetic field environment. An accommodation cavity is provided inside the cover shell 410 for installing the main coil 100, the auxiliary coil 200, and the cathode coil 300, ensuring the fixed positions of these key components and precise control of the magnetic field interaction between them. The bottom plate 420 is used to seal the accommodation cavity of the cover shell 410 and is made of non-magnetic conductive material to avoid interfering with the magnetic field distribution or causing energy loss, ensuring the purity and stability of the magnetic field. In this way, it not only effectively prevents the influence of external factors (such as dust, moisture, etc.) on internal components but also improves the overall performance of the system by shielding external electromagnetic interference.

[0069] Optionally, the cover shell 410 of the magnetic cutting module 10 can be covered on the housing of the electron gun 700 to utilize the housing to enclose the accommodation cavity inside the cover shell 410. That is to say, the bottom plate 420 of the housing 400 of the magnetic cutting module 10 can be the housing of the electron gun 700. In this way, the number of additional components can be reduced, and the overall structure can be simplified. This not only reduces the manufacturing cost but also reduces the assembly complexity.

[0070] In one embodiment, as Figure 2 shown, the cover shell 410 is made of magnetic conductive material, one end of the first pole shoe 500 and the second pole shoe 600 is connected to the cover shell 410, and the other end of the first pole shoe 500 and the second pole shoe 600 passes through the bottom plate 420 and is arranged towards the electron gun 700.

[0071] In this embodiment, the cover shell 410 is made of magnetic conductive material, which helps to concentrate and optimize the magnetic field distribution, thereby improving the performance of the entire magnetic cutting module 10. One end of the first pole shoe 500 and the second pole shoe 600 is connected to the cover shell 410, using the magnetic conductive characteristics of the cover shell 410 to enhance the magnetic field guiding effect and ensure that the magnetic field can be efficiently transmitted to the required area. At the same time, the other end of the first pole shoe 500 and the second pole shoe 600 passes through the bottom plate 420 and is arranged towards the electron gun 700, directly guiding the magnetic field to the corresponding position of the electron gun 700. In this way, not only can the magnetic field act precisely on the initial position of the electron beam formation, but also the control ability of the electron beam movement trajectory is enhanced. Specifically, the first pole shoe 500 optimizes the initial emission state of the electron beam by guiding the magnetic field generated by the main coil 100 and the auxiliary coil 200 to the corresponding area; while the second pole shoe 600 further enhances the cutting magnetic field near the cathode, improving the control effect of the cathode coil 300 and the auxiliary coil 200 on the electron beam. Overall, the quality and stability of the electron beam are improved, and at the same time, it also helps to achieve the compactness and miniaturization design of the system.

[0072] In one embodiment, asFigure 1 As shown in FIG. 1 or FIG. 2, the first pole shoe 500 includes a connecting section 510 and a magnetic conduction section 520. The connecting section 510 is disposed between the main coil 100 and the auxiliary coil 200. The first end of the connecting section 510 is connected to the cover shell 410, and the second end of the connecting section 510 passes through the bottom plate 420. This ensures that the first pole shoe 500 can be stably fixed on the housing 400 of the magnetic shear module 10, and can effectively guide the magnetic fields generated by the main coil 100 and the auxiliary coil 200 to the corresponding regions of the electron gun 700. The magnetic conduction section 520 is connected to the second end of the connecting section 510, and the magnetic conduction section 520 is disposed toward the junction of the anode and the cathode of the electron gun 700 to guide the magnetic fields generated by the main coil 100 and the auxiliary coil 200 to the junction. The magnetic conduction section 520 can optimize the magnetic field distribution, ensure that the electron beam travels along the expected path from the beginning, reduce the occurrence of deviation and ripple phenomena. In this way, the magnetic fields generated by the main coil 100 and the auxiliary coil 200 can be more precisely concentrated and guided to the position where the electron beam is formed and starts to accelerate.

[0073] Optionally, as Figure 2 shown, the connecting section 510 and the magnetic conduction section 520 are arranged at an angle. This angle can be an acute angle, an obtuse angle or a flat angle, and the specific angle is not limited here. The key is that this angle depends on the position that the magnetic conduction section 520 needs to point to in actual applications. Through the setting of this angle, the magnetic field can be effectively guided more concentratedly to a specific direction or region, thereby improving the control accuracy of the magnetic field on the movement trajectory of the electron beam.

[0074] Optionally, the connecting section 510 and the magnetic conduction section 520 are not arranged at an angle, and both the connecting section 510 and the magnetic conduction section 520 extend in the same direction. However, the shape of the magnetic conduction section 520 has a protruding end, such as a triangle, a polygon, an arc, a trapezoid, etc. The protruding section of the magnetic conduction section 520 is used to point to the corresponding position of the electron gun 700 for magnetic conduction work.

[0075] In a feasible embodiment, as Figure 2 shown, the electron beam emitted from the cathode of the electron gun 700 needs to pass through the anode hole 710. The magnetic conduction section 520 of the first pole shoe 500 is arranged to point to the anode hole 710 to control the electron beam to pass through the anode and be ejected.

[0076] In an embodiment, as Figure 2As shown, the first end of the second pole shoe 600 is connected to the cover shell 410. The second pole shoe 600 passes through the bottom plate 420 and is arranged towards the cathode of the electron gun 700, aiming to enhance the magnetic field intensity and distribution uniformity in the cathode region, thereby optimizing the initial emission state of the electron beam. Specifically, the first end of the second pole shoe 600 is connected to the cover shell 410, and the magnetic field is efficiently guided to the second pole shoe 600 by utilizing the magnetic conductivity of the cover shell 410, while the other end extends near the cathode of the electron gun 700 and directly acts on the starting region where the electron beam is formed. In this way, not only can the cusp magnetic field generated by the cathode coil 300 and the auxiliary coil 200 in the cathode region be enhanced, but also the control ability of the magnetic field on the electron beam can be effectively improved, and the deviation and ripple phenomena caused by the uneven magnetic field can be reduced.

[0077] Optionally, the first pole shoe 500, the second pole shoe 600, and the cover shell 410 are integrally formed.

[0078] In one embodiment, the main coil 100 has a first current access end. When the main coil 100 accesses a first current through the first current access end, a first magnetic field is generated at the anode of the electron gun 700; the auxiliary coil 200 has a second current access end. When the auxiliary coil 200 accesses a second current through the second current access end, a second magnetic field is generated at the junction of the anode and the cathode of the electron gun 700; the cathode coil 300 has a third current access end. When the cathode coil 300 accesses a third current through the third current access end, a third magnetic field is generated at the cathode of the electron gun 700.

[0079] It can be understood that the main coil 100, the auxiliary coil 200, and the cathode coil 300 are each equipped with independent current access ends (the first current access end, the second current access end, and the third current access end), and these current access ends can be connected to an external power supply or control system. For example, a stable current input can be provided to each coil through an adjustable DC power supply, so that the current of each coil can be independently adjusted, thereby achieving precise control of the magnetic field intensity and direction. According to Ampere's law in electromagnetism, a magnetic field is generated around a coil when current passes through it, and the intensity of the magnetic field is proportional to the current passing through the coil. Therefore, by adjusting the magnitude of the current, the magnetic field intensity generated by the coil can be directly changed. In addition, the direction of the magnetic field is determined by the direction of the current and follows the right-hand rule, which will not be elaborated here.

[0080] In practical applications, the current access terminal can be connected to a constant current source or a programmable power supply. For example, in a laboratory environment, a digitally controlled DC power supply can be used to adjust the current magnitude in real time while monitoring the change of the magnetic field. In industrial equipment, an integrated current controller may be adopted and remotely operated through a software interface to ensure the stability and flexibility of the system.

[0081] In one embodiment, the second current is greater than the first current, and the third current is less than the first current and the second current. In this way, it is possible to achieve that the intensity of the second magnetic field is greater than that of the first magnetic field, and the intensity of the third magnetic field is less than that of the first magnetic field and the second magnetic field. It can be understood that, according to the actual application scenario, the magnitudes of the first current, the second current, and the third current can be adjusted to change the relative magnitudes of the first magnetic field, the second magnetic field, and the third magnetic field.

[0082] In one embodiment, in order to achieve that the intensity of the third magnetic field is less than that of the first magnetic field and the second magnetic field, when the corresponding currents are the same, it can be achieved by the number of turns of the coil. It can be that the number of turns of the cathode coil 300 is more than that of the main coil 100 and the auxiliary coil 200; similarly, in order to achieve that the intensity of the second magnetic field is greater than that of the first magnetic field, when the corresponding currents are the same, it can be achieved by the number of turns of the cathode coil 300 being more than that of the main coil 100.

[0083] In one embodiment, the coil diameter of the main coil 100 is greater than the coil diameters of the auxiliary coil 200 and the cathode coil 300.

[0084] It can be understood that the larger coil diameter of the main coil 100 helps to provide a wider magnetic field coverage range, ensuring suitable initial conditions for the electron beam when entering the acceleration stage. Since the main coil 100 is located near the anode of the electron gun 700, its main function is to provide a stable basic magnetic field environment for the entire system. The larger coil diameter means that the magnetic field can be more evenly distributed over the entire anode area, thereby reducing the influence of magnetic field non-uniformity on the electron beam path and enabling the electron beam to maintain a straight movement or a preliminary rotation state in a wider area. In addition, the smaller coil diameters of the auxiliary coil 200 and the cathode coil 300 provide higher magnetic field concentration and stronger local control capabilities. The smaller coil diameter makes the magnetic field concentrated in a specific small area, enhancing the local intensity of the magnetic field, thereby effectively guiding the electron beam and enabling it to stabilize to the ideal orbit faster.

[0085] In one embodiment, the length of the main coil 100 is greater than the length of the auxiliary coil 200. It can be understood that the longer length of the main coil 100 helps to provide a more uniform and stable magnetic field distribution within its coverage area. Since the main function of the main coil 100 is to provide a basic magnetic field environment for the electron beam in the anode region, its longer length ensures that the magnetic field can remain consistent over a larger spatial range, thereby reducing the deviation or instability of the electron beam caused by magnetic field non-uniformity. In contrast, the shorter length of the auxiliary coil 200 enables it to provide a high-intensity local magnetic field more concentratedly at the junction of the anode and the cathode, so as to provide a stronger radial force within the critical transition section where the electron beam changes from linear motion to rotational motion.

[0086] The present invention also provides an electron gun device 20, as Figure 1 shown. The electron gun device 20 includes an electron gun 700 and at least two magnetic shear modules 10. The specific structure of the magnetic shear module 10 refers to the above embodiments. Since the electron gun device 20 adopts all the technical solutions of the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be elaborated herein one by one.

[0087] In one embodiment, the two magnetic shear modules 10 are oppositely arranged on both sides of the electron gun 700. When the two magnetic shear modules 10 are oppositely arranged on both sides of the electron gun 700, the generated magnetic fields can complement and balance each other, so as to achieve a more uniform magnetic field distribution within the entire working area of the electron gun 700. In this way, it helps to eliminate the asymmetric effect that may be brought by the unilateral magnetic field and ensure that the electron beam is subjected to a balanced magnetic field during acceleration and transmission.

[0088] Optionally, the two magnetic shear modules 10 can be symmetrically distributed on both sides of the electron gun 700 with the axis of the electron gun 700 as the axis of symmetry, that is, the distances between the two magnetic shear modules 10 and the electron gun 700 are equal and they are arranged on opposite sides. In this way, it can ensure the uniformity of the magnetic fields on both sides and effectively improve the overall quality and stability of the electron beam.

[0089] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the various embodiments of the present application, and they should all be covered within the scope of the claims and the specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A magnetic shear module (10), characterized in that, The magnetic shear module (10) is used for an electron gun (700), and the electron gun (700) includes a cathode and an anode. The magnetic shear module (10) includes: A main coil (100) disposed corresponding to the anode of the electron gun (700), and the main coil (100) is used to generate a first magnetic field; An auxiliary coil (200) disposed corresponding to the junction of the anode and the cathode of the electron gun (700). The cathode of the auxiliary coil (200) is connected to the anode of the main coil (100) through a first pole shoe (500). The auxiliary coil (200) is used to generate a second magnetic field. The direction of the first magnetic field is the same as that of the second magnetic field, and the intensity of the first magnetic field is less than that of the second magnetic field; One end of the first pole shoe (500) faces the junction of the anode and the cathode of the electron gun (700) to guide the first magnetic field and the second magnetic field to the junction; A cathode coil (300) disposed corresponding to the cathode of the electron gun (700). The anode of the cathode coil (300) is connected to the anode of the auxiliary coil (200) through a second pole shoe (600). The cathode coil (300) is used to generate a third magnetic field. The direction of the third magnetic field is opposite to those of the first magnetic field and the second magnetic field, and the intensity of the third magnetic field is less than that of the first magnetic field.

2. The magnetic shear module (10) according to claim 1, wherein The magnetic shear module (10) further includes a housing (400), and the housing (400) includes: A cover shell (410) having a receiving cavity, and the main coil (100), the auxiliary coil (200) and the cathode coil (300) are all disposed in the receiving cavity; A bottom plate (420) sealingly closing the receiving cavity of the cover shell (410), and the bottom plate (420) is made of a non-magnetic material.

3. The magnetic shear module (10) according to claim 2, wherein The cover shell (410) is made of a magnetic material; One end of the first pole shoe (500) and the second pole shoe (600) is connected to the cover shell (410), and the other ends of the first pole shoe (500) and the second pole shoe (600) pass through the bottom plate (420) and face the electron gun (700).

4. The magnetic shear module (10) according to claim 3, characterized in that, The first pole shoe (500) includes: A connecting section (510) disposed between the main coil (100) and the auxiliary coil (200). The first end of the connecting section (510) is connected to the cover shell (410), and the second end of the connecting section (510) passes through the bottom plate (420); A magnetic conduction section (520) connecting the second end of the connecting section (510), and the magnetic conduction section (520) faces the junction of the anode and the cathode of the electron gun (700) to guide the magnetic fields generated by the main coil (100) and the auxiliary coil (200) to the junction; The connecting section (510) and the magnetic conduction section (520) are arranged at an angle.

5. The magnetic shear module (10) according to claim 3, wherein The first end of the second pole shoe (600) is connected to the cover housing (410), and the second pole shoe (600) passes through the bottom plate (420) and is arranged facing the cathode of the electron gun (700).

6. The magnetic shear module (10) according to any one of claims 1 to 5, characterized in that, The main coil (100) has a first current access end. When the main coil (100) accesses a first current through the first current access end, a first magnetic field is generated at the anode of the electron gun (700). The auxiliary coil (200) has a second current access end. When the auxiliary coil (200) accesses a second current through the second current access end, a second magnetic field is generated at the junction of the anode and the cathode of the electron gun (700). The cathode coil (300) has a third current access end. When the cathode coil (300) accesses a third current through the third current access end, a third magnetic field is generated at the cathode of the electron gun (700).

7. The magnetic shear module (10) according to claim 6, characterized in that, The second current is greater than the first current, and the third current is less than the first current and the second current.

8. The magnetic shear module (10) according to any one of claims 1 to 5, characterized in that, The coil diameter of the main coil (100) is greater than the coil diameters of the auxiliary coil (200) and the cathode coil (300).

9. The magnetic shear module (10) according to any one of claims 1 to 5, characterized in that, The length of the main coil (100) is greater than the length of the auxiliary coil (200).

10. An electron gun device (20), characterized in that, The electron gun device (20) includes: an electron gun (700); and at least two magnetic cutting modules (10) as described in any one of claims 1 to 9, and the two magnetic cutting modules (10) are oppositely arranged on both sides of the electron gun (700).

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