• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    The present invention relates to an electron accelerator comprising: (a) a resonant cavity (1), (b) a source (20) of electrons for radially injecting a beam (40) of electrons into the resonant cavity, (c) ) an RF system coupled to the resonant cavity for accelerating electrons of the electron beam along radial paths, (d) a magnet unit (30i) having a deflection magnet for generating a magnetic field in a chamber ( 31) to deflect an electron beam emerging from the resonant cavity through a deflection window along a first radial path in the median plane, Pm, and to redirect the electron beam into the resonant cavity through a window deflection in the direction of the central axis along a second radial path, characterized in that the deflection magnet is composed of first and second permanent magnets (32) positioned on both sides of the median plane, Pm.
    公开号:BE1026069B1
    申请号:E2017/5775
    申请日:2017-10-27
    公开日:2019-10-03
    发明作者:Michel Abs；Willem Kleeven；De Walle Jarno Van；Jérémy Brison；Denis Deschodt
    申请人:Ion Beam Applications S.A.；
    IPC主号:
    专利说明:

    COMPACT ELECTRON ACCELERATOR HAVING PERMANENT MAGNETS
    Field of the Invention [1] The present invention relates to an electron accelerator having a resonant cavity centered on a central axis, Zc, and creating an oscillating electric field used to accelerate electrons along several radial paths. A Rhodotron® is an example of such an electron accelerator. An electron accelerator according to the present invention may be more compact and require less electrical power than an accelerator according to the current state of the art. This allows, for the first time, to realize a mobile electron accelerator. The elements constituting the electron accelerator are designed to ensure a more efficient and versatile realization.
    Description of the State of the Prior Art [2] Electron accelerators with a resonant cavity are well known in the art. For example, EP0359774 describes an electron accelerator comprising:
    (a) a resonant cavity consisting of a closed closed conductor comprising:
    • an outer wall comprising an outer cylindrical part with a central axis, Zc, and having an inner surface forming an outer conductor section, and, • an inner wall contained inside the outer wall and comprising a inner cylindrical part with the central axis, Zc, and with an outer surface forming an inner conductor section, the resonant cavity being symmetrical with respect to a median plane, Pm, normal to the central axis, Zc, and crossing the outer cylindrical part and the inner cylindrical part, (b) an electron source provided for radially injecting an electron beam into the resonant cavity, from an introduction opening on the outer conductor towards the central axis, Zc, along the median plane, Pm, (c) an RF system coupled to the resonant cavity and designed to generate an electric field, E, between the outer conductor and the inner conductor eur, oscillating at a frequency (îRf), to accelerate the electrons of the electron beam along radial trajectories in the median plane, Pm, extending from the conductor
    BE2017 / 5775 outside towards the inside conductor and from the inside conductor towards the outside conductor;
    (d) a magnet system comprising several electromagnets intended to deflect the trajectories of the electron beam from a radial trajectory towards a different radial trajectory, each in the median plane, Pm, and passing through the central axis, Zc, from the electron source to an electron beam output.
    In what follows, the term “rhodotron” is used as a synonym for “electron accelerator with a resonant cavity”.
    [3] As shown in Figure 1 (b), the electrons in an electron beam are accelerated along the diameter (two rays, 2R) of the resonant cavity by the electric field, E, generated by the RF system between the outer conductor section and the inner conductor section and between the inner conductor section and the outer conductor section. The oscillating electric field, E, first accelerates the electrons over the distance between the outer conductor section and the inner conductor section. The polarity of the electric field changes when the electrons pass through the area around the center of the resonant cavity inside the inner cylindrical part. This zone located around the center of the resonant cavity provides protection against the electric field to electrons which continue their trajectory at constant speed. Then, the electrons are again accelerated in the segment of their trajectory included between the section of interior conductor and the section of exterior conductor. The polarity of the electric field changes again when the electrons are deflected by an electromagnet. The process is then repeated as often as necessary for the electron beam to reach a target energy where it is released out of the rhodotron. The electron trajectory in the median plane, Pm, therefore has the shape of a flower (see Figure 1 (b)).
    [4] A rhodotron can be combined with external equipment such as a beam line and a beam scanning system. Rhodotron can be used for sterilization, polymer modification, dough processing, cold pasteurization of food, for detection and safety purposes, etc.
    [5] At present, the known rhodotrons are large, have a high production cost and require a high power source of energy to use them. They are designed to be placed on a fixed place and with a predetermined configuration.
    BE2017 / 5775
    The application of an electron beam in different places requires drawing an additional beam line, with all the costs and the additional technical problems associated with it.
    [6] There is a demand in the industry for smaller, more compact, versatile and lower cost rhodotrons which consume less energy and which are preferably mobile units. However, resonant cavities of smaller diameter require greater power to accelerate electrons over shorter distances, which affects the energy consumption of such compact rhodotrons. Regardless of the size of a rhodotron, energy consumption can be reduced by powering the RF source and accelerating electrons during only a fraction of the rhodotron's operating cycle as described in EP2804451. Even so, however, energy consumption is higher with smaller resonant cavities.
    [7] A smaller diameter resonant cavity also has a smaller outer circumference, which reduces the space available to connect the electron source and all electromagnets in the magnet system to the resonant cavity. The production of small compact rhodotrons is more complex and more extensive than that of rhodotrons according to the current state of the art.
    [8] The present invention provides a compact rhodotron requiring low energy, which is mobile and which is economical to produce. These advantages are described in more detail in the following paragraphs.
    Summary of the invention [9] The present invention is defined in the accompanying independent claims. Preferred embodiments are defined in the dependent claims. In particular, the present invention relates to an electron accelerator comprising a resonant cavity, an electron source, an RF system, and at least one magnet unit.
    [10] The resonant cavity consists of a closed closed conductor comprising:
    An outer wall comprising an outer cylindrical part having a central axis, Zc, and having an inner surface forming a section (1o) of outer conductor, and,
    BE2017 / 5775 • an interior wall contained inside the exterior wall and comprising an interior cylindrical part with central axis Zc, and provided with an exterior surface forming a section (1i) of interior conductor.
    The resonant cavity is symmetrical with respect to a median plane, Pm, normal to the central axis, Zc, and crossing the outer cylindrical part and the inner cylindrical part.
    [11] The electron source is intended to radially inject an electron beam into the resonant cavity, from an introduction opening on the section of outer conductor towards the central axis, Zc, along the median plane, Pm .
    [12] The RF system is coupled to the resonant cavity and intended to generate an electric field, E, between the outer conductor section and the inner conductor section, oscillating at a frequency (îrf), to accelerate the beam electrons of electrons following radial trajectories in the median plane, Pm, extending from the outer conductor section towards the inner conductor section and from the inner conductor section towards the outer conductor section .
    [13] The magnet unit or units comprise a deflection magnet composed of first and second permanent magnets positioned on either side of the median plane, Pm, and intended to generate a magnetic field in a deflection chamber in fluid communication with the resonant cavity by at least one deflection window, the magnetic field being provided to deflect an electron beam emerging from the resonant cavity through the deflection window (s) along a first radial trajectory in the median plane, Pm , and to redirect the electron beam into the resonant cavity through the deflection window (s) or through a second deflection window towards the central axis along a second radial trajectory in the median plane, Pm, said second radial trajectory being different from the first radial trajectory.
    [14] Each of the first and second permanent magnets is preferably formed by a multiplicity of discrete magnet elements, arranged side by side in a network parallel to the median plane, Pm, comprising one or more rows of magnet elements discrete and arranged on either side of the deviation chamber with respect to the median plane, Pm. This allows fine adjustment of the magnetic field by adding or removing one or more of said discrete magnet elements. Preferably, the discrete magnet elements are in the form of prisms such as rectangular parallelepipeds, cubes or cylinders.
    BE2017 / 5775 [15] The magnet unit may also include first and second support elements each having a surface of magnets supporting the discrete magnet elements, and a chamber surface separated from the surface of magnets by a thickness of the support element, said chamber surface forming or being contiguous with a wall of the deflection chamber. Preferably, the chamber surface and the magnet surface of each of the first and second support elements are planar and parallel to the median plane, Pm. Depending on the number of discrete elements necessary to create a magnetic field of desired intensity, the chamber area of each of the first and second support members may have a smaller area than the area of the magnet area. In this case, each of the first and second support elements preferably comprises a conical surface remote from the resonant cavity and joining the surface of magnets to the surface of the chamber.
    [16] The electron accelerator of the present invention may also include a tool for adding or removing discrete magnet elements to the magnet surfaces of the first and second support elements. The tool has an elongated profile, preferably an L-profile or a C-profile, for receiving a desired number of discrete magnet elements in a given row of the array, and an elongated pusher, slidably mounted on the elongated profile, used to push the discrete magnet elements along the elongated profile.
    [17] The magnet unit may also include a cylinder head holding the first and second support elements in their desired position. Preferably, the cylinder head allows fine adjustment of the position of the first and second support elements.
    [18] In a preferred embodiment, the resonant cavity of the electron accelerator of the present invention is formed by:
    • a first half-shell (11), provided with a cylindrical exterior wall of interior radius R, and of central axis Zc, • a second half-shell (12), provided with a cylindrical exterior wall of interior radius R , and of central axis Zc, and • an element (13) of central ring of internal radius R, sandwiched at the median plane, Pm, between the first and second half-shells.
    BE2017 / 5775
    In this embodiment, the surface forming the outer conductor section is formed by an inner surface of the cylindrical outer wall of the first and second half-hulls, and by an inner edge of the central ring element, which preferably is flush with the surfaces. interior of both the first and second half-shells.
    [19] Each of the first and second half-shells may include the cylindrical outer wall, a lower cover, and a central upright protruding from the lower cover. The electron accelerator can also include a central chamber sandwiched between the central uprights of the first and second half-shells. The central chamber has a cylindrical peripheral wall with a central axis Zc, having openings aligned radially with corresponding deflection windows and the introduction opening. Preferably, the surface forming the interior conductor section is formed by an exterior surface of the central uprights and by the peripheral wall of the central chamber sandwiched therebetween.
    [20] Part of the central ring member may extend radially beyond an outer surface of the outer wall of both the first and second half shells. This is advantageous in that the unit or units of magnets can thus be adjusted on said part of the central ring element.
    [21] The deflection chamber of the magnet unit or units can be formed by a cavity hollowed out in a thickness of the central ring element, the deflection window being formed at the inner edge of the ring element central, facing the center of the central ring element.
    [22] Preferably, an electron accelerator according to the present invention comprises N units of magnets, with N> 1, and the deflection magnets of n units of magnets are composed of first and second permanent magnets, with 1 < n <N.
    [23] Preferably, the unit or units of magnets form a magnetic field in the deflection chamber of between 0.05 T and 1.3 T, preferably 0.1 T to 0.7 T.
    Description of the Drawings [24] These and other aspects of the invention will be explained in more detail by way of example and with reference to the accompanying drawings.
    BE2017 / 5775
    Figure 1 schematically shows an example of an electron accelerator according to the present invention, (a) a section along a plane (X, Z), and (b) a view on a plane (X, Y), normal to (X, Z).
    Figure 2 schematically shows an electron accelerator according to the present invention, (a) an exploded view of various elements of a preferred embodiment of the present invention, (b) ready to mount on a support for a use and (c) an enlarged view of an embodiment of the construction of the central ring and the deflection chamber.
    Figure 3 shows an example of a magnet unit used in a preferred rhodotron according to the present invention (a) sectional view along a plane (Z, r), r being in the median plane, Pm and crossing the axis central, Zc, and (b) a perspective view showing a tool for adding or removing discrete magnet elements to the magnet unit.
    Figure 4 shows how the direction of the electron beam extracted from the rhodotron can be changed for an electron beam of (a) 10 MeV and (b) 6 MeV.
    The figures are not drawn to scale.
    detailed description
    Rhodotron [25] Figures 1 and 2 show an example of a rhodotron according to the invention and comprising:
    (a) a resonant cavity (1) consisting of a closed closed conductor;
    (b) a source (20) of electrons;
    (c) a vacuum system (not shown);
    (d) an RF system (70);
    (e) a magnet system comprising at least one unit (30i) of magnets.
    Resonant cavity [26] The resonant cavity (1) comprises:
    BE2017 / 5775 (a) a central axis, Zc;
    (b) an outer wall comprising an outer cylindrical part coaxial with the central axis, Zc, and provided with an inner surface forming a section (1o) of outer conductor;
    (c) an inner wall contained inside the outer wall and comprising an inner cylindrical part coaxial with the central axis, Zc, and provided with an outer surface forming a section (1i) of inner conductor;
    (d) two lower covers (11b, 12b) joining the outer wall and the inner wall, thereby closing the resonant cavity;
    (e) a median plane, Pm, normal to the central axis, Zc, and crossing the inner cylindrical part and the outer cylindrical part. The intersection of the median plane and the central axis defines the center of the resonant cavity.
    [27] The resonant cavity (1) is divided into two parts symmetrical with respect to the median plane, Pm. This symmetry of the resonant cavity with respect to the median plane relates to the geometry of the resonant cavity and does not take into account the presence of possible openings, p. ex. used to connect the system (70) to RF or the vacuum system. The inner surface of the resonant cavity thus forms a closed hollow conductor in the form of a toroidal volume.
    [28] The median plane, Pm, can be vertical, horizontal or have any appropriate orientation with respect to the ground on which the rhodotron rests. Preferably, it is vertical.
    [29] The resonant cavity (1) may have openings used to connect the system (70) to RF, and the vacuum system (not shown). These openings are preferably made in at least one of the two lower covers (11b, 12b).
    [30] The outer wall also has openings crossed by the median plane, Pm. For example, the outer wall has an introduction opening for introducing an electron beam (40) into the resonant cavity (1). It also has an electron beam outlet (50) for releasing the electron beam (40) accelerated to a desired energy from the resonant cavity. It also includes deflection windows (31w), putting the resonant cavity in fluid communication with a
    BE2017 / 5775 corresponding deflection chamber (31, see below). Generally, a rhodotron has several units of magnets and several deflection windows.
    [31] A rhodotron generally accelerates the electrons of an electron beam to energies which can be between 1 and 50 MeV, preferably between 3 and 20 MeV, ideally between 5 and 10 MeV.
    [32] The inner wall has radially aligned openings with corresponding deflection windows (31w) allowing the passage of an electron beam through the inner cylindrical part along a rectilinear radial trajectory.
    [33] The surface of the resonant cavity (1) consisting of a closed closed conductor is made of a conductive material. For example, the conductive material can be one of gold, silver, platinum, aluminum, preferably copper. The outer and inner walls and the lower covers can be made of steel coated with a layer of conductive material.
    [34] The resonant cavity (1) may have a diameter, 2R, of between 0.3 m and 4 m, preferably between 0.4 m and 1.2 m, ideally between 0.5 m and 0.7 m . The height of the resonant cavity (1), measured parallel to the central axis, Zc, can be between 0.3 m and 4 m, preferably between 0.4 m and 1.2 m, ideally between 0.5 m and 0.7 m.
    [35] The diameter of a rhodotron comprising a resonant cavity (1), an electron source (20), a vacuum system, an RF system (70) and one or more units of magnets, measured parallel to the median plane, Pm, can be between 1 and 5 m, preferably between 1.2 and 2.8 m, ideally between 1.4 and 1.8 m. The height of the rhodotron measured parallel to the central axis, Zc, can be between 0.5 and 5 m, preferably between 0.6 and 1.5 m, ideally between 0.7 and 1.4 m.
    Electron source, vacuum system and RF system [36] The electron source (20) is intended to generate and introduce a beam (40) of electrons into the resonant cavity along the median plane, Pm, in direction of the central axis, Zc, through an introduction opening. For example, the electron source can be an electron gun. As is well known to those with ordinary skill in the art, an electron gun is an electrical component that produces a narrow collimated electron beam, which has precise kinetic energy.
    BE2017 / 5775 [37] The vacuum system includes a vacuum pump used to pump air out of the resonant cavity (1) and to create a vacuum therein.
    [38] The RF system (70) is coupled to the resonant cavity (1) via a coupler and typically includes an oscillator designed to oscillate at a resonant frequency, îrf, to generate an RF signal, followed by an amplifier or a chain of amplifiers used to achieve a desired output power at the end of the chain. The RF system thus generates a resonant radial electric field, E, in the resonant cavity. The resonant radial electric field, E, oscillates so as to accelerate the electrons of the electron beam (40) along a trajectory lying in the median plane, Pm, from the section of outer conductor to the section of inner conductor, and then from the inner conductor section to a deflection window (31w). The resonant radial electric field, E, is generally of the “TE001” type, which defines that the electric field is transverse (“TE”), has a symmetry of revolution (first “0”), is not canceled along a radius of the cavity (second “0”), and is half a cycle of said field in a direction parallel to the central axis Z.
    Magnet system [39] The magnet system comprises at least one magnet unit (301) comprising a deflection magnet composed of first and second permanent magnets (32) positioned on either side of the median plane, Pm , and designed to generate a magnetic field in a deflection chamber (31). The deflection chamber is in fluid communication with the resonant cavity (1) by at least one deflection window (31w).
    [40] Preferably, the magnet system comprises several magnet units (30i with i = 1, 2, ... N). N is equal to the total number of magnet units and is between 1 and 15, preferably between 4 and 12, ideally between 5 and 10. The number N of magnet units corresponds to (N + 1) accelerations electrons from a beam (40) of electrons before it leaves the rhodotron with a given energy. For example, Figure 4 in (a) represents rhodotrons comprising nine (9) units (30i) of magnets producing an electron beam of 10MeV, while the rhodotrons in (b) comprise five (5) units of magnets, producing a 6 MeV electron beam.
    BE2017 / 5775 [41] The electron beam is injected into the resonant cavity by the electron source (20) through the introduction opening along the median plane, Pm. It follows a radial trajectory in the median plane, Pm, said traversing trajectory:
    (a) the interior wall through a first opening;
    (b) the center of the resonant cavity (i.e. the central axis, Zc);
    (c) the interior wall through a second opening;
    (d) the outer wall through a first deflection window (31w);
    (e) a first deflection chamber (31).
    The electron beam is then deflected by the deflection magnet of the magnet unit (30i) and reintroduced into the resonant cavity through the first or a second deflection window along a different radial path. The electron beam can follow such a path N number of times until it reaches a target energy. The electron beam is then extracted from the resonant cavity through an electron beam outlet (50).
    In this document, a radial trajectory is defined as a rectilinear trajectory perpendicularly crossing the central axis, Zc.
    Permanent magnets [42] Although rhodotrons according to the current state of the art use electromagnets in the magnet units used to deflect the trajectories of an electron beam by returning them to the resonant cavity, a rhodotron according to the The present invention differs from such rhodotrons according to the current state of the art in that the deflection magnet of at least one unit (30i) of magnets is composed of first and second permanent magnets (32).
    [43] Generally, a rhodotron has more than one unit (30i) of magnets. In a preferred embodiment comprising a total of N units of magnets, with N> 1, n units of magnets comprise a deflection magnet composed of first and second permanent magnets (32), with 1 <n <N. By example, the rhodotron illustrated in Figure 4 (a) has N = 9 units of magnets, while the rhodotron illustrated in Figure 4 (b) has N = 5 units of magnets. In Figure 4 (a) and (b), all the magnet units have permanent magnets (n = N). A rhodotron according to the present invention requires that at least one
    BE2017 / 5775 of the N units of magnets has permanent magnets, so that one or more (N - n) units of magnets of a rhodotron can be electromagnets. In practice, a rhodotron can comprise for example an electromagnet (i.e. n = N- 1), or two electromagnets (i.e. n = N- 2), or three electromagnets (i.e. d. n = N - 3).
    [44] A rhodotron preferably has at most one electromagnet. For example, the first unit (301) of magnets located opposite the source (20) of electrons may differ from (N - 1) other units of magnets, because the electron beam reaches said first unit of magnets at a lower speed than other magnet units. In order to return the electron beam to the resonant cavity in phase with the oscillating electric field, the deflection path in the first magnet unit must be slightly different from the (N - 1) remaining magnet units. The first magnet unit (301) can therefore be an electromagnet, allowing easy fine adjustment of the magnetic field generated in the corresponding deflection chamber (31).
    [45] The transition from rhodotrons according to the current state of the art, where all the magnet units are equipped with electromagnets, to a rhodotron according to the present invention where at least one unit of magnets is, preferably several units magnets are, fitted with permanent magnets, might appear retrospectively as an easy approach, but this is not the case and a person with ordinary qualifications in the trade would have a strong prejudice against the fact of adopt such an approach for the following reasons. A rhodotron is very sophisticated equipment, requiring exact fine tuning to ensure that the electron beam will follow the flower-shaped path illustrated in Figure 1 (b). The RF system and the dimensions of the resonant cavity must ensure that an electric field oscillating at a desired frequency, fRF, and of wavelength Xrf, is produced. In particular, the configuration of the rhodotron must guarantee that the distance, L, of a loop traversed by an electron of the central axis, Zc, to a unit (30i) of magnets following a first radial trajectory, through the chamber (31) of deflection, and returning from the unit (30i) of magnets to the central axis, Zc, along a second radial trajectory (i.e. a flower petal of the flower-shaped path illustrated on Figure 1 (b))) is a multiple of the wavelength, Xrf, of the electric field, L = M Xrf, M being an integer, M being preferably equal to 1, and therefore L = Xrf.
    [46] The radius of the circular path followed by the electron beam in the deflection chamber depends on the intensity of the magnetic field created between the first and second
    BE2017 / 5775 permanent magnets (32) of the deflection magnet. Fine adjustment of said magnetic field in each of the rhodotron's magnet units is essential to ensure that the electron beam follows the pre-established flower-shaped path in phase with the oscillating electric field. This can be easily achieved with an electromagnet simply by controlling the current sent to the coils. Any deviation in the deflection path of the electron beam at one magnet unit is reproduced and amplified in the other magnet units, to the point that the final radial path of the electron beam can be offset by the electron beam output (50), thus rendering the rhodotron unusable and dangerous.
    [47] A permanent magnet, on the other hand, generates a given magnetic field which is intrinsic to the material used and which can only be varied by changing the volume of the permanent magnet. A person with ordinary qualifications in the trade will therefore have a strong prejudice against using a permanent magnet for any of the magnet units of a rhodotron, since the fine adjustment of the magnetic field in the chamber deflection seems impossible, or at least much more difficult than with an electromagnet. Cutting pieces or segments of a permanent magnet is not a viable option, as it lacks control and reproducibility. For this reason alone, it is not obvious for a person with ordinary qualifications in the trade to replace the magnet unit of a rhodotron equipped with a deflection magnet composed of first and second electromagnets by a unit of 'magnets equipped with a deflection magnet composed of first and second permanent magnets (32), because fine adjustment of the magnetic field to ensure proper operation of the rhodotron is not achievable.
    [48] In the present invention, the deflection magnet of at least one unit (30i) of magnets is composed of first and second permanent magnets (32). The prejudice of the qualified person concerning the absence of fine adjustment of the magnetic field in the deflection chamber is overcome in the present invention by the preferred embodiment which follows. As illustrated in Figure 3, the magnetic field, Bz, in the deflection chamber created by first and second permanent magnets can be finely adjusted by forming each of the first and second permanent magnets by arranging a multiplicity of elements (32i) d discrete magnets, side by side in a network parallel to the median plane, Pm. The array is formed by one or more rows of discrete magnet elements. A network is arranged on either side of the deviation chamber with respect to the median plane, Pm. The discrete magnet elements are preferably in the form of prisms, such as rectangular parallelepipeds, cubes or cylinders. Discrete magnet elements in parallelepipeds
    BE2017 / 5775 rectangles can be formed from two cubes stacked on top of each other and holding each other by magnetic forces.
    [49] By varying the number of discrete magnet elements in each array, it is possible to vary the magnetic field created in the deflection chamber accordingly. For example, 12x12x12 mm cubes of Nd-Fe-B permanent magnet material can be stacked in pairs to form discrete magnet elements in rectangular parallelepipeds of dimensions 12x 12 x 24 mm. Other magnetic materials can be used instead, such as permanent ferrite or Sm-Co magnets. Such a discrete magnet element disposed on opposite sides of the deflection chamber can create a magnetic field of about 3.9.10 -3 Tesla (T) (= 38.8 Gauss (G), with 1 G = 10 - 4 T). For a desired magnetic field, Bz, of about 0.6 T (= 6060 G), 156 of said discrete magnet elements are required on either side of the deflection chamber. They can be arranged in a 12x13 network. The magnetic field, Bz, in the deflection chamber can thus be adjusted in discrete steps of 3.9.10 -3 / 6.10 -1 = 0.6%, by adding or removing one by one of the discrete magnet elements to the networks . The graph in Figure 3 (a) represents the magnetic field in a deflection chamber in a radial direction, r, for two examples of numbers of rows of discrete elements arranged on either side of the deflection chamber. The solid line represents a higher magnetic field created by a larger number of discrete magnet elements than the dotted line. The measurements show that a very constant magnetic field can be obtained over the entire deflection chamber with permanent magnets formed, in particular, by discrete magnet elements, according to the present invention.
    [50] The essential fine adjustment of the magnetic field in the individual deflection chambers being made possible by means of permanent magnets made up of networks of discrete magnet elements, the use of permanent magnets has several advantages over the use of electromagnets. First, the overall energy consumption of the rhodotron is reduced, since the permanent magnets do not need to be powered. This is advantageous for mobile units, which are called upon to be connected to energy sources whose power capacity is limited. As mentioned above, even by supplying the RF source for only a fraction of the rhodotron's operating cycle as described in EP2804451, the power requirement of a rhodotron increases with the decrease in the diameter, 2R, of the resonant cavity. The use of permanent magnets therefore contributes to reducing the energy consumption of the rhodotron.
    BE2017 / 5775 [51] The permanent magnets can be coupled directly against the external wall of the resonant cavity, while the coils of electromagnets must be positioned at a certain distance from said external wall. By allowing the magnet units to be directly adjacent to the outer wall, the construction of the rhodotron is considerably simplified and the production cost reduced accordingly as described below with reference to Figure 2 (a) and (c) . In addition, permanent magnets require no electrical wiring, water cooling system, thermal insulation against overheating, or any regulator of any kind configured, for example, to regulate the current or flow of water. The absence of these elements coupled to the magnet units also considerably reduces production costs.
    [52] When in use, a rhodotron according to the current state of the art equipped with electromagnets undergoes a power failure, the electromagnets stop generating a magnetic field, but a residual magnetic field persists, caused by all the ferromagnetic components of a magnet unit. When electricity is restored, the entire equipment needs to be calibrated in order to produce the desired magnetic fields in each unit of magnets. It is a delicate process. Power cuts may not occur very often in fixed installations, but they become recurrent with mobile units, connected to electrical installations of varying capacity and quality.
    [53] As shown in Figure 3 (a), each magnet unit has first and second support elements (33) each having a surface (33m) of magnets supporting the discrete magnet elements, and a surface (33c) of a chamber separated from the surface of the magnets by a thickness of the support element. The chamber surface forms or is contiguous to a wall of the deflection chamber. In Figure 3 (a) the chamber surfaces of the two support elements are contiguous with opposite first and second walls of the deflection chamber, which is formed as a cavity in a central ring element (13) as discussed below compared to Figure 2 (a). The first and second support elements must be made of a ferromagnetic material to conduct the magnetic field coming from the first and second permanent magnets (32) formed of the elements (32i) of discrete magnets as mentioned above. If the first and second support elements are contiguous to opposite first and second walls of the deflection chamber, said walls must also be made of ferromagnetic material, for the same reason.
    BE2017 / 5775 [54] The chamber surface and the magnet surface of each of the first and second support elements are preferably plane and parallel to the median plane, Pm. As shown in Figure 3 (a), the chamber area of each of the first and second support members has a smaller area than the area of the magnet area. This can happen if the number of rows needed in arrays of discrete magnet elements to create a magnetic field in the deflection chamber, for example from 0.2 to 0.7 T (= 2000 to 7000 G), s 'extend in the radial direction further than the chamber area. This is not a problem, as the magnetic field lines can be routed from the most distant parts of the magnet surface to the chamber surface through the first and second support members along a conical surface. (33t) remote from the resonant cavity and joining the surface of magnets to the surface of the chamber. These conical surfaces of the first and second support elements widen the range of magnetic fields obtainable with discrete magnet elements, since the area of the magnet surfaces can thus be larger than the area of the support surfaces. chamber, while maintaining a homogeneous magnetic field in the deflection chamber.
    [55] For reasons of stability of the magnetic field, it is preferred to size the first and second support elements so as to reach the saturation of the magnetic field in the support elements when they are loaded to their maximum capacity of discreet magnets.
    [56] The magnetic field required in the deflection chamber must be sufficient to deflect the path of an electron beam leaving the resonant chamber along a radial path through a deflection window (31w) in a circular arc. angle greater than 180 ° to return it to the resonant chamber along a second radial trajectory. For example, in a rhodotron with nine (9) units (30i) of magnets as illustrated in Figure 1 (b), the angle can be 198 °. The radius of the arc of a circle can be of the order of 40 to 80 mm, preferably between 50 and 60 mm. The chamber surface must therefore have a length in a radial direction of the order of 65 to 80 mm. The magnetic field necessary to deflect an electron beam following such arcs of a circle is between values of the order of 0.05 T and 1.3 T, preferably 0.1 T to 0.7 T, in function of the energy (speed) of the electron beam to be deflected. By way of illustrative example, using the elements of discrete magnets 12 mm in width measured in a radial direction described above, each creating a magnetic field of approximately 39 G (= 3.9 10 -3 T), 156 discrete elements arranged in a network of 13 rows of 12 discrete magnet elements
    BE2017 / 5775 are necessary on both sides of the deflection chamber to create a magnetic field of 0.6 T. If each row is separated from its neighboring rows by a distance of 1 mm, a length measured in a direction radial of at least 160 mm from the magnet surfaces is necessary to support the 156 discrete magnet elements (= 13 rows x 12 mm + 12 intervals x 1 mm = 160 mm). In this example, the length of the magnet surface can therefore be of the order of 2 to 2.3 times greater than the length of the chamber surface in a radial direction (= 160/80 to 160/70 = 2 to 2.3).
    [57] Arrays of discrete magnet elements can therefore have a maximum number of rows between 8 and 20 rows, preferably between 10 and 15 rows, each row counting between 8 and 15 discrete magnet elements, preferably between 10 and 14 discrete magnet elements. With a larger number of discrete elements in each array, a finer adjustment of the magnetic field, Bz, in the deflection chamber can be made.
    [58] Adding or removing discrete magnet units to a magnet surface can easily be done with a tool specifically designed for this purpose. As illustrated in Figure 3 (b), the tool (60) has an elongated profile (61). The elongated profile (61) is preferably an L-profile or a C-profile, used to receive a desired number of discrete magnet elements in a given row of the array. An elongated pusher (62) is slidably mounted on the elongated profile to push the discrete magnet elements along the elongated profile. The tool, loaded with a desired number of discrete magnet elements, is positioned opposite the array row where the discrete magnet elements are to be inserted. The discrete magnet elements are pushed along the row using the pusher. When loading the discrete magnet elements on the elongated profile, they repel each other and are distributed along the length of the elongated profile with a space separating them from each other. When the discrete magnet elements are pushed using the elongated pusher, an initial resistance must be overcome, then the discrete magnet elements are literally sucked in by the network and they line up along the corresponding row in contact mutual.
    [59] The removal of a row or part of a row of discrete magnet elements from a network can be carried out very easily with the tool (60) by positioning it at the level of the row to be removed and pushing with the elongated pusher along the row to expel the discrete magnet elements on the other side of the row. With the tool (60), it is possible to
    BE2017 / 5775 easily vary the magnetic field in a deflection chamber, and even fine-tune it, by removing or adding individual discrete magnet elements, or entire rows of discrete magnet elements. This can be done either in the factory, by the equipment supplier, or in situ by the user.
    [60] In order to hold the elements of the magnet units in place, in particular the first and second support elements and, in particular to ensure that the magnetic circuit of a magnet unit is closed, with magnetic lines forming closed loops, the magnet units include a yoke (35), shown in Figure 3. The yoke must be made of a ferromagnetic material to perform this latter function, acting as a flux return. The cylinder head preferably allows fine adjustment of the position of the first and second support elements.
    Modular construction of the electron accelerator [61] As illustrated in Figure 4, rhodotrons can be supplied in a multiplicity of different configurations. For example, different users may need rhodotrons producing electron beams of different energies. The energy of the electron beam leaving a rhodotron can be controlled by the number of radial acceleration paths followed by the electron beam before reaching an output (50), which depends on the number of units of active magnets in the rhodotron. The rhodotrons in Figure 4 (a) (= left column) have nine (9) magnet units and are configured to produce a 10 MeV electron beam. The rhodotrons in Figure 4 (b) (= right column) have five (5) magnet units and are configured to produce a 6 MeV electron beam. Different users may need an accelerated electron beam leaving the rhodotron along a trajectory of a given orientation. The rhodotrons in Figure 4 (a1) and 4 (b1) (= top line) produce an electron beam leaving the rhodotron horizontally (i.e. at an angle of 0 °). The rhodotrons in Figure 4 (a2) and 4 (b2) (= middle line) and in Figure 4 (a3) and 4 (b3) (= bottom line) produce an electron beam leaving the rhodotron vertically, respectively downwards (i.e. with an angle of -90 °) and upwards (i.e. with an angle of 90 °).
    [62] Rhodotrons according to the current state of the art are generally positioned “horizontally,” ie with their median plane, Pm, horizontal and parallel to the surface on which the rhodotron rests. By rotating the rhodotron around the central (vertical) axis, Zc, the electron beam exit (50) can be directed in any direction
    BE2017 / 5775 following the median plane, Pm. However, it is not possible to direct the electron beam exit (50) out of the median plane (eg 45 ° or vertically 90 ° or 270 ° to the median plane). The rhodotrons of the present invention are preferably positioned “vertically,” i.e. with the central axis, Zc, horizontal and parallel to the surface on which the rhodotron rests and, therefore, the median plane, Pm, being vertical. A rhodotron unit installed in a vertical orientation has several advantages. Firstly, this leads to a reduction in the surface area occupied by the rhodotron. This reduces the space required for the installation of a rhodotron unit to the point that mobile rhodotron units can be installed in the cargo of a truck. Second, the vertical orientation of a rhodotron allows the electron beam exit (50) to be directed in any direction in space. The rhodotron can be pivoted around the central (horizontal) axis, Zc, as illustrated in Figure 4, to reach any direction along the median plane, Pm, and it can be pivoted around a vertical axis of the median plane, Pm, crossing the central axis, Zc, to reach any direction in space. In order to reduce production costs, a new set of modules or elements has been developed as described below, allowing the production of rhodotrons having any orientations of the electron beam output with the same set of modules or elements, hence a "dial system" suitable for any direction of the electron beam exit (50).
    [63] To date, two rhodotrons of different configurations require many parts of the rhodotron to be redesigned individually, said parts having to be tailored and produced individually. As mentioned above, the present invention proposes an entirely innovative concept, comprising a set of elements or modules common to rhodotrons of any configuration. Different configurations of rhodotrons can be obtained by modifying the assembly of the elements, and not the elements themselves. In this way, the number of tools and molds required for the production of rhodotrons can be significantly reduced, thereby reducing production costs.
    [64] The modular construction of rhodotrons according to the present invention is illustrated in the exploded view of Figure 2 (a). The resonant cavity of a rhodotron is formed by:
    • a first half-shell (11), provided with a cylindrical exterior wall of interior radius R, and of central axis Zc, • a second half-shell (12), provided with a cylindrical exterior wall of radius
    BE2017 / 5775 interior R, and of central axis Zc, and • an element (13) of central ring of interior radius R, sandwiched at the median plane, Pm, between the first and second half-shells.
    [65] Referring to Figure 2 (a), each of the first and second half-shells has a cylindrical outer wall, a lower cover (11b, 12b), and a central post (15p) protruding from the lower cover. A central chamber (15c) can be sandwiched between the central uprights of the first and second half-shells.
    [66] As mentioned above, the resonant cavity has a geometry of revolution similar to a torus. The entire interior surface of the resonant cavity is made of a conductive material. In particular, the surface forming the section (1o) of outer conductor is formed by an inner surface of the cylindrical outer wall of the first and second half-shells, and by an inner edge of the central ring element, which is preferably flush the interior surfaces of both the first and second half shells. The surface forming the inner conductor section (1i) is formed by an outer surface of the central uprights and by the peripheral wall of the central chamber sandwiched therebetween.
    [67] As can be seen in FIGS. 2 (a) and 3 (a), the element (13) of the central ring has first and second main surfaces separated from each other by a thickness of the latter. this. A portion of the central ring member extends radially beyond an outer surface of the outer wall of both the first and second half-hulls, forming a flange extending radially outward. The magnet units (30i) can be mounted on and adjusted over said flange. The adjustment between the magnet units and the flange preferably allows a certain play to finely align the magnet units with the median plane, Pm, and the trajectory of the electron beam. In particular, the magnet units can preferably be inclined in a radial direction and translated in a direction parallel to the central axis, Zc, to position the magnet unit in perfect symmetry with respect to the median plane, and they can be translated parallel to the median plane, Pm, and pivoted around an axis parallel to the central axis, Zc, for perfect alignment with the trajectory of the electron beam.
    [68] In a particularly preferred embodiment, the deflection chamber (31) of at least one magnet unit can be formed by a cavity recessed in the thickness of the central ring element, the window (31w ) of deflection being formed at the inner edge of
    BE2017 / 5775 the central ring element, facing the center of the central ring element and the central axis, Zc. Preferably, several deflection chambers, ideally all the deflection chambers of the rhodotron are formed by individual recessed cavities in the thickness of the central ring element, the corresponding deflection windows being formed in the inner edge of the element of central ring, facing the central axis, Zc. This construction significantly reduces the production costs of rhodotrons compared to models according to the current state of the art for the following reasons.
    [69] Because the electromagnets have coils between which a magnetic field is formed, they cannot be located in the immediate vicinity of the outer wall of the resonant cavity. The deflection chambers in rhodotrons according to the current state of the art, provided with electromagnets, are therefore produced in the form of individual components, which are coupled to the resonant cavity by means of two conduits, one aligned with the path. radial of the electron beam leaving the resonant cavity, the other aligned with the radial trajectory of the electron beam entering the resonant cavity. The two conduits must be coupled at one end to the magnet unit and at the other end to the outer wall of the resonant cavity. The coupling of the conduits can be carried out by one or more methods, including welding, screwing, riveting, etc. An O-ring seal can be used to seal the coupling. This coupling operation can only be carried out manually by a qualified craftsman. It is time consuming, quite expensive and not without the risk of misalignment of the various components (tubes, chamber, etc.).
    [70] Using permanent magnets, the magnet units can be located in the immediate vicinity of the outer wall of the resonant cavity. By arranging the deflection chambers like recesses in the thickness of the central ring element, they can all be automatically machined with precision from a single ring-shaped plate. The magnet units can then be coupled to the central ring over each deflection chamber thus formed. These operations are much more precise, reproducible, quick and economical than the coupling of each individual magnet unit to the external resonant cavity by means of two welded conduits, as mentioned above.
    [71] The deflection chambers (31) can be economically formed as follows. As mentioned above, the central ring element can be made of a plate
    BE2017 / 5775 in the form of a ring comprising first and second main surfaces separated by a thickness of the ring-shaped plate. As shown in Figure 2 (a) and (c), each cavity forming a deflection chamber can be produced by forming an open recess at the first main surface and at the inner edge of the ring-shaped plate. The recess can be formed by machining, water jet cutting, laser ablation, or any other technique known in the art. A cover plate (13p) can then be coupled to the first main surface to close the recess and form a cavity open only at the inner edge to form one or more deflection windows. A sealing ring can be used to seal the interface between the central ring element and the cover plate. The cover plate can be fixed by welding or by means of screws or rivets.
    [72] Figure 2 (a) shows a central ring element (13) provided with eight (8) deflection chambers, closed on the first main surface by cover plates (13p) and opening at the inner edge of the central ring element with a single elongated deflection window (13w) per deflection chamber. The single elongated window must extend in the circumferential direction at least so as to envelop the trajectories of the electron beam leaving and re-entering the resonant cavity.
    [73] In an alternative embodiment illustrated in Figure 2 (c), each deflection chamber can open at the inner edge by two smaller deflection windows instead of a single large deflection window as in the the above embodiment. A first deflection window is aligned with a radial path of exit of the electron beam leaving the resonant cavity, and a second deflection window is aligned with a radial path of entry of the electron beam entering the resonant cavity downstream the circular path with an angle greater than 180 ° followed by the electron beam in the deflection chamber. With these designs, multiple deflection cavities can be formed in a single or a small number of automated operations, with deflection windows (13w) in perfect and reproducible alignment with the desired radial paths of the electron beam.
    [74] To further rationalize the production of a rhodotron, it is preferred that the first and second half-shells have an identical geometry and that each is coupled to the central ring element with sealing means (14) for ensure the hermeticity of the resonant cavity. Half-shells can thus be produced in series,
    BE2017 / 5775 without taking into account that they are called upon to form a first or a second half-shell of the resonant cavity. In addition to the cylindrical outer wall already mentioned, each of the first and second half-shells may include a lower cover (11b, 12b), and a central upright (15p) projecting from the lower cover. The inner conductor section (1i) can be formed by the first and second uprights coming into contact when the first and second half-shells are coupled on either side of the central ring element. Alternatively, as shown in Figure 2 (a), a central chamber (15c) can be sandwiched between the central uprights of the first and second demicoques. The central chamber has a cylindrical peripheral wall with a central axis Zc. With or without a central chamber, openings are distributed radially on the peripheral wall of the central chamber or of the first and second uprights, in alignment with corresponding deflection windows, the introduction opening, and the beam exit (50). electron. The surface forming the interior conductor section is thus formed by an exterior surface of the central uprights and, if a central chamber is used, by the peripheral wall of the central chamber sandwiched therebetween.
    [75] With the modules described above, a resonant cavity can be formed by assembling the second half-shell (12) to the element (13) of the central ring, by means well known in the art, such as bolts , rivets, welding or soldering. The assembly thus formed can be assembled with the first half-shell, the central chamber being sandwiched between the first and second uprights, to complete the resonant cavity provided with an introduction opening, an outlet (50) electron beam and a multiplicity of deflection windows (31w) in fluid communication with deflection chambers, and in radial alignment with corresponding openings in the cylindrical wall of the central chamber. With a part of the central ring element (13) forming a flange extending radially outward and enveloping the deflection chambers, the magnet units can be coupled to said flange in the corresponding positions of the deflection chambers. No electrical wiring is necessary in the assembly thus produced, since the permanent magnets do not need to be powered. This greatly reduces the cost of production and the cost of use.
    [76] The first half-shell has at least one opening for coupling to the RF system (70). If, as shown in Figure 2 (b), said opening (s) are offset from the central axis, Zc, the angular position of the first half-shell is fixed by the position of the opening in question relative to the RF system. The whole as well
    BE2017 / 5775 obtained can be further stabilized by sandwiching it between two plates as shown in Figure 2 (b), firmly holding the magnet units in place. The whole can then be positioned in a support. The RF system (70) can be coupled to the openings in the bottom cover of the first half-shell. Only the RF system requires a power supply to operate, since unlike electromagnets, permanent magnets do not need to be powered. All electrical wiring is therefore concentrated in the RF system, which can be produced separately as standard units. This is advantageous for production, but also facilitates the production of a mobile rhodotron unit, requiring fewer supply connections.
    [77] The various configurations of the rhodotron illustrated in Figure 4 have been mentioned above, showing how the configurations of a rhodotron can vary depending on the applications in terms of energy and orientation of the beam (40 ) of electrons. With the modular construction described above, all configurations can be obtained with the same set of modules or elements. The white central circles in the rhodotrons of Figure 4 represent the lower cover (11b) of the first demicoque. The lower cover (11b) is provided with two openings for coupling to an RF system whose orientation is fixed and cannot be changed. The openings are illustrated in Figure 4 with a black circle on the left side and a white circle on the right side, showing that in all configurations, the angular orientation of the first demohull is kept fixed.
    [78] For a given energy of the electron beam produced by the rhodotron (eg 10MeV in the rhodotrons of Figure 4 (a1-3) and 6MeV in the rhodotrons of Figure 4 (a1-3)), the angular orientation of the outlet (50) can be changed by varying the angular orientation of the element (13) of the central ring and, optionally, of the second half-shell with respect to the first half-shell, of which the position must remain fixed.
    [79] For a given orientation of the electron beam (eg 0 ° in Figure 4 (a1) and (b1), -90 ° in Figure 4 (a2) and (b2), and 90 ° in Figure 4 (a3) and (b3)), the energy of the electron beam can be changed by varying the number of activated magnet units. This can be accomplished simply by removing or adding a number of magnet units or, alternatively, removing or loading discrete magnet elements from or to a number of magnet units. The gray magnet units (30i) in Figure 4 (b)
    BE2017 / 5775 represent units of active magnets, while the white rectangles, with dotted outlines, represent units of inactive magnets. The outlet (50) can easily be pivoted by setting up a radially branching channel in each deflection chamber. In the absence of a magnetic field to influence the radial trajectory of an electron beam, the latter can continue its radial trajectory through said channel and exit the rhodotron.
    [80] All the different configurations illustrated in Figure 4 can be made with a single set of modules illustrated in Figure 2 (a), while with rhodotrons according to the current state of the art, each new configuration would require redesign the components again, with a specific assembly for each new configuration. Such a rationalization of the production of rhodotrons with a unique set of components allows a drastic reduction in production costs and, at the same time, higher reproducibility and reliability of the rhodotrons thus produced.
    [81] It is now possible to produce mobile rhodotrons, of relatively small dimensions, requiring a smaller number of supply connections. Such a mobile rhodotron can be loaded onto a truck and transported where necessary. The truck can also carry an electric generator to provide total autonomy.
    BE2017 / 5775
    Ref. Detail 1 i inner conductor 1 o outside conductor 1 resonant cavity 11 first half-shell 11 b first half-shell lower cover 12 second half-hull 12 b second half-shell lower cover 13 central ring 13 p cover plate 14 O-ring seal 20 electron source 30 1 ... individual magnet unit 30 i magnet unit (in general) 31w deflection window 31 deflection chamber 32 i discreet magnet element 32 permanent magnet 33 c room surface 33 m magnet surface 33 support element 35 magnet unit yoke 40 electron beam 50 electron beam exit 60 tool for adding or removing magnet elements 61 elongated profile of the tool 62 extended tool plunger 70 RF system
    权利要求:
    Claims (14)
    [1]
    1. Electron accelerator comprising:
    (a) a resonant cavity (1) consisting of a closed hollow conductor comprising:
    • an outer wall comprising an outer cylindrical part with a central axis, Zc, and having an inner surface forming a section (1o) of outer conductor, and • an inner wall contained inside the outer wall and comprising an inner cylindrical part with central axis Zc, and provided with an outer surface forming a section (1i) of internal conductor, the resonant cavity being symmetrical with respect to a median plane, Pm, normal to the central axis, Zc , and crossing the outer cylindrical part and the inner cylindrical part, (b) a source (20) of electrons provided for radially injecting a beam (40) of electrons into the resonant cavity, through an introduction opening located on the section of external conductor, in the direction of the central axis, Zc, along the median plane, Pm, (c) an RF system coupled to the resonant cavity and designed to generate an electric field, E, between the secti on of outer conductor and the inner conductor section, oscillating at a frequency (fRF), to accelerate the electrons of the electron beam along radial paths in the median plane, Pm, extending from the outer conductor section towards the inner conductor section and from the inner conductor section towards the outer conductor section, (d) at least one magnet unit (30i) having a deflection magnet adapted to generate a magnetic field in a deflection chamber (31) in fluid communication with the resonant cavity by at least one deflection window (31w), the magnetic field being provided for deflecting an electron beam emerging from the resonant cavity through the window (s) deflection along a first radial path in the median plane, Pm, and to redirect the electron beam into the resonant cavity through the o u the deflection windows or through a second deflection window in the direction of the central axis along a second radial trajectory in the median plane, Pm, said second radial trajectory being different from the first radial trajectory,
    BE2017 / 5775 characterized in that the deflection magnet is composed of first and second permanent magnets (32) positioned on either side of the median plane, Pm.
    [2]
    2. An electron accelerator according to claim 1, each of the first and second permanent magnets (32) being formed by a multiplicity of elements (32i) of discrete magnets, placed side by side in a network parallel to the median plane, Pm , comprising one or more rows of discrete magnet elements and arranged on either side of the deflection chamber with respect to the median plane, Pm.
    [3]
    3. The electron accelerator according to claim 2, in which the discrete magnet elements are in the form of prisms, in particular rectangular parallelepipeds, cubes or cylinders.
    [4]
    4. The electron accelerator according to claim 2 or 3, comprising first and second support elements (33) each comprising a surface (33m) of magnets supporting the discrete magnet elements, and a chamber surface (33c) separated from the surface of magnets by a thickness of the support element, said chamber surface forming or being contiguous with a wall of the deflection chamber.
    [5]
    5. The electron accelerator of claim 4, wherein the chamber surface and the magnet surface of each of the first and second support members are planar and parallel to the median plane, Pm.
    [6]
    6. The electron accelerator of claim 5, wherein the chamber surface of each of the first and second support members has a smaller area than the area of the magnet surface, and each of the first and second support members has a conical surface (33t) remote from the resonant cavity and joining the surface of magnets to the surface of the chamber.
    [7]
    7. An electron accelerator according to any one of claims 4 to 6, comprising a tool (60) for adding or removing discrete magnet elements to the magnet surfaces of the first and second support elements, said tool comprising an elongated profile (61), preferably an L-profile or a C-profile, for receiving a desired number of discrete magnet elements in a given row of the array, and an elongated pusher (62), mounted sliding on the elongated profile, used to push the discrete magnet elements along the elongated profile.
    BE2017 / 5775
    [8]
    8. An electron accelerator according to any one of claims 4 to 7, in which a yoke maintains the first and second support elements in their desired position, said yoke preferably allowing fine adjustment of the position of the first and second elements Support.
    [9]
    9. An electron accelerator according to any one of the preceding claims 1 to 8, in which the resonant cavity is formed by:
    • a first half-shell (11), provided with a cylindrical exterior wall of interior radius R, and of central axis Zc, • a second half-shell (12), provided with a cylindrical exterior wall of interior radius R , and of central axis Zc, and • an element (13) of central ring of internal radius R, sandwiched at the median plane, Pm, between the first and second half-shells, the surface forming the conductor section outer being formed by an inner surface of the cylindrical outer wall of the first and second half shells, and by an inner edge of the central ring member, which preferably is flush with the inner surfaces of both the first and second half shells .
    [10]
    10. An electron accelerator according to claim 9 which precedes, • each of the first and second half-shells comprising the cylindrical outer wall, a lower cover (11b, 12b), and a central upright (15p) rising from the lower cover. , and • a central chamber (15c) being sandwiched between the central uprights of the first and second half-shells, said central chamber comprising a cylindrical peripheral wall of central axis Zc, having openings aligned radially with corresponding deflection windows and with the insertion opening, the surface forming the interior conductor section being formed by an exterior surface of the central uprights and by the peripheral wall of the central chamber sandwiched therebetween.
    [11]
    11. The electron accelerator according to claim 9 or 10, a part of the central ring element extending radially beyond an outer surface of the outer wall of both the first and second half-shells, and the unit or units of magnets being adjusted
    BE2017 / 5775 on said part of the central ring element.
    [12]
    12. The electron accelerator as claimed in claim 11, in which the deflection chamber of the unit or units of magnets is formed by a cavity hollowed out in a thickness of the central ring element, the deflection window. being formed at the edge
    5 inside the central ring element, facing the center of the central ring element.
    [13]
    13. The electron accelerator as claimed in claim 1, comprising N units of magnets, with N> 1, and the deflection magnets of n units of magnets being composed of first and second permanent magnets (32), with 1 <n <N.
    [14]
    14. Electron accelerator according to any one of the preceding claims, in
    10 where the unit or units of magnets form a magnetic field in the deflection chamber of between 0.05 T and 1.3 T, preferably 0.1 T to 0.7 T.
    类似技术:
    公开号 | 公开日 | 专利标题
    BE1025838B1|2019-10-18|COMPACT ELECTRON ACCELERATOR HAVING FIRST AND SECOND HALF SHELLS
    BE1026069B1|2019-10-03|COMPACT ELECTRON ACCELERATOR HAVING PERMANENT MAGNETS
    EP0662195A1|1995-07-12|Reduced length plasma engine with closed electron deviation.
    LU85895A1|1986-12-05|CYCLOTRON
    WO2017149434A1|2017-09-08|Method for generating a magnetic field and magnetic field generator
    EP2353347A1|2011-08-10|Device and method for producing and/or confining a plasma
    EP1130949B1|2005-09-07|Electromagnetic device for cold atom production
    CA2763820A1|2010-12-09|Magnetic field generator and magnetocaloric device comprising said magnetic field generator
    FR3018316A1|2015-09-11|PLASMIC PROPELLER WITH HALL EFFECT
    EP0499514B1|1995-09-20|Mode converter and power-dividing device for a microwave tube, and microwave tube with such a device
    EP0946961B1|2007-03-07|Magnetic system, particularly for ecr sources, for producing closed surfaces of equimodule b of any form and dimensions
    BE1020221A5|2013-06-04|PARTICLE ACCELERATOR AND METHOD FOR MAINTAINING PARTICLE ACCELERATOR.
    FR2691285A1|1993-11-19|Focusing system with periodic permanent magnets with X-Z geometry.
    EP2472555A1|2012-07-04|Device for the generation of hyperfrequency waves, comprising a plurality of magnetrons
    EP2747117B1|2021-06-23|Device for generating microwaves with dual cathodes
    FR2607345A1|1988-05-27|Synchrotron
    FR3015109A1|2015-06-19|ION SOURCE WITH ELECTRONIC CYCLOTRONIC RESONANCE
    FR2815810A1|2002-04-26|Electron accelerator, for non-destructive testing or irradiation of products or substances, has cavity excited so that it presents maximum electric field in direction of cavity axis and zero magnetic field
    EP1251544B1|2007-05-30|Microwave amplifier electron tube with miniature entry plug and method of fabrication
    FR3093269A1|2020-08-28|Multiple injection line for particle accelerator cavity
    FR2820880A1|2002-08-16|Semiconductor material etching ion source multiple charged beam having ionization reactor with extractor wall/ionization input and input/output poles with enclosing flux magnetic field.
    WO2012107699A1|2012-08-16|Inductive plasma torch
    FR2943172A1|2010-09-17|INTERACTION NOZZLE FOR RF POWER CAVITY
    同族专利:
    公开号 | 公开日
    JP6913002B2|2021-08-04|
    US10271418B2|2019-04-23|
    CN207854258U|2018-09-11|
    EP3319402A1|2018-05-09|
    EP3319402B1|2021-03-03|
    BE1026069A1|2019-09-26|
    JP2018078100A|2018-05-17|
    CN108064113B|2021-06-01|
    US20180132342A1|2018-05-10|
    CN108064113A|2018-05-22|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    JPH11214200A|1998-01-29|1999-08-06|Nissin Electric Co Ltd|Charged particle accelerator|
    FR2616032B1|1987-05-26|1989-08-04|Commissariat Energie Atomique|COAXIAL CAVITY ELECTRON ACCELERATOR|
    US5506475A|1994-03-22|1996-04-09|Martin Marietta Energy Systems, Inc.|Microwave electron cyclotron electron resonance ion source with a large, uniformly distributed, axially symmetric, ECR plasma volume|
    FR2815810B1|2000-10-20|2003-11-28|Thomson Tubes Electroniques|COMPACT ELECTRON ACCELERATOR WITH RESONANT CAVITY|
    CN2938701Y|2006-08-16|2007-08-22|宁波超能科技股份有限公司|Petaling irradiation accelerator|
    EP2509399B1|2011-04-08|2014-06-11|Ion Beam Applications|Electron accelerator having a coaxial cavity|
    CA2787794C|2012-08-27|2016-04-19|Mikhail Gavich|Multirhodotron|
    EP2804451B1|2013-05-17|2016-01-06|Ion Beam Applications S.A.|Electron accelerator having a coaxial cavity|
    EP3319403B1|2016-11-07|2022-01-05|Ion Beam Applications S.A.|Compact electron accelerator comprising first and second half shells|
    EP3319402B1|2016-11-07|2021-03-03|Ion Beam Applications S.A.|Compact electron accelerator comprising permanent magnets|EP3319402B1|2016-11-07|2021-03-03|Ion Beam Applications S.A.|Compact electron accelerator comprising permanent magnets|
    EP3661335B1|2018-11-28|2021-06-30|Ion Beam Applications|Vario-energy electron accelerator|
    CN110582156B|2019-07-31|2021-06-01|中国科学院近代物理研究所|Particle beam deflection device for annular particle accelerator|
    EP3876679A1|2020-03-06|2021-09-08|Ion Beam Applications|Synchrocyclotron for extracting beams of various energies|
    法律状态:
    2019-11-04| FG| Patent granted|Effective date: 20191003 |
    优先权:
    申请号 | 申请日 | 专利标题
    EP16197603.0A|EP3319402B1|2016-11-07|2016-11-07|Compact electron accelerator comprising permanent magnets|
    EP16197603.0|2016-11-07|
    [返回顶部]