Cutting magnet for miniaturized particle accelerator

Abstract

The invention relates to a cutting magnet for a miniaturized particle accelerator, and the cutting magnet comprises a magnet core which is of an upper and lower half structure, the large-diameter end of the magnet core is provided with a notch groove, the notch groove is an air gap, and the inner wall of the notch groove forms a pole face; the magnet exciting coil comprises a saddle-shaped coil body formed by winding a plurality of turns of wires, and the multiple turns of wires at the inlet end and the outlet end of the saddle-shaped coil body are vertically arranged at intervals. The coil main body is embedded into an air gap of the magnet core; the plurality of turns of wires at the inlet end and the outlet end of the coil main body are respectively welded with the power connection copper bar, so that the plurality of turns of wires are connected in series, and the power connection copper bar is used for being connected with an external cable. The structure is simple, installation is convenient, and the installation space and the manufacturing cost are saved.

Description

Technical Field

[0001] The present invention relates to the technical field of accelerator magnets, and specifically relates to a cutting magnet for a miniaturized particle accelerator. Background Art

[0002] With the continuous development of science and technology, particle accelerators are not only important experimental devices for scientific research, but also have broad application prospects in fields such as industrial and agricultural production, medical and health, energy and environment, and aerospace. With the continuous development of current radiotherapy technology, medical accelerators are continuously evolving towards higher precision, higher efficiency, and smaller volume. Therefore, the requirements for some special components are getting higher and higher. As one of the key components for injection and extraction in a synchrotron, since the cutting magnet is located at the intersection of the synchrotron ring and the injection / extraction transport line, in a miniaturized medical accelerator, the cutting magnet needs to be miniaturized and lightweight on the premise of efficiently deflecting the beam current without affecting the circulating beam current.

[0003] According to the working principle of the cutting magnet, considering the limitations of the position space of the cutting magnet and the leakage field shielding, the overall structure is relatively complex. The iron core is usually laminated from silicon steel sheets with a C-shaped structure. The excitation coil is wound in a saddle-shaped structure in a vertically symmetric manner to ensure the magnetic field quality, and a single-turn waterway structure is adopted to ensure the cooling effect. This structure can effectively deflect the beam current and at the same time ensure the operating stability of the excitation coil under a large electromagnetic force. However, its installation conditions in the accelerator determine that a bracket with a slide rail mechanism must be used so that the iron core can be moved out through the slide rail first when installing the coil to ensure that there is enough space for the coil to be installed smoothly. After the magnet iron core is moved out, the lower coil is first placed in place and fixed, the vacuum pipe is installed, and then the magnet iron core is moved back, and the upper coil is adjusted and installed in the remaining narrow space. The installation process requires manual support and adjustment of the upper coil for a long time. Secondly, the moving mechanism results in a relatively large radial dimension of the magnet bracket, usually 2.5 times the width of the iron core, which requires a large installation space and the manufacturing cost is also relatively high.

[0004] Therefore, for a miniaturized medical particle accelerator, there is an urgent need for a compact cutting magnet structure to save space and cost. Summary of the Invention

[0005] Aiming at the above problems, the purpose of the present invention is to provide a cutting magnet for a miniaturized particle accelerator. For a miniaturized accelerator, especially for a cutting magnet operating in a DC mode, this structure is simple, easy to install, and saves installation space and manufacturing cost. To achieve the above purpose, the present invention adopts the following technical solutions: The cutting magnet for a miniaturized particle accelerator described in the present invention includes: The magnet iron core has an upper and lower split structure. A notch groove is provided at the large-diameter end of the magnet iron core. The notch groove is an air gap and the inner wall forms a pole face. The exciting coil includes a coil body wound by a plurality of turns of wire into a saddle shape, and a plurality of turns of wire at the inlet end and the outlet end of the saddle-shaped coil body are respectively arranged vertically at intervals; the coil body is embedded in the air gap of the magnet iron core. The power connection copper bar. A plurality of turns of wire at the inlet end and the outlet end of the coil body are respectively welded to the power connection copper bar to connect the plurality of turns of wire in series, and the power connection copper bar is used for connection with an external cable.

[0006] For the described cutting magnet, preferably, each turn of wire is made of a copper wire with an inner circle wrapped by an outer square inter-turn insulation, and the copper wire has a hollow tubular structure.

[0007] For the described cutting magnet, preferably, there are two sets of exciting coils, and the two sets of exciting coils are arranged oppositely.

[0008] For the described cutting magnet, preferably, it further includes a cooling water pipe assembly; the cooling water pipe assembly includes a main manifold and branch water pipes; two main manifolds are respectively arranged vertically, and a plurality of branch water pipes are respectively connected to each main manifold; wherein, a plurality of branch water pipes on one main manifold are respectively connected to a plurality of turns of wire at the inlet end of the coil body; a plurality of branch water pipes on the other main manifold are respectively connected to a plurality of turns of wire at the outlet end of the coil body.

[0009] For the described cutting magnet, preferably, it further includes a shielding and fixing assembly. The shielding and fixing assembly has a shell structure that is open at both the top and bottom and is in a C shape. The shielding and fixing assembly covers the large-diameter end of the magnet iron core and is fixed to the magnet iron core for shielding the leakage field.

[0010] For the described cutting magnet, preferably, it further includes a coil support assembly; the coil support assembly includes a first support and a second support; the first support is fixedly arranged on the first side of the magnet iron core for fixing the exciting coil; the second support is fixedly arranged on the second side of the magnet iron core for fixing the exciting coil; the main manifold is fixed on the coil support assembly.

[0011] For the described cutting magnet, preferably, it further includes a magnet support; the magnet support is fixed to the bottom of the coil support assembly for supporting the entire cutting magnet device.

[0012] For the described cutting magnet, preferably, the magnet iron core is made of the soft magnetic material of pure iron for electrical engineering DT4.

[0013] For the described cutting magnet, preferably, the inter-turn insulation is semi-overlapped and wrapped with polyimide and glass ribbon, and is formed by vacuum epoxy casting.

[0014] For the described cutting magnet, preferably, the top of the magnet core has a lifting lug, and the lifting lug is used to lift the upper half of the magnet core.

[0015] Due to the adoption of the above technical solutions, the present invention has the following advantages: Through the above technical solutions, the present invention can not only simplify the processing technology of the iron core, but also make it relatively easy to install the exciting coil without repeatedly moving the iron core and disassembling the coil bracket due to the upper and lower iron core structures. In this way, the bracket structure does not need to move the guide rail structure and is simpler, saving installation space and manufacturing cost in a miniaturized accelerator. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] By reading the following detailed description of the preferred embodiments, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered to be a limitation of the present invention. Throughout the drawings, the same reference numerals are used to represent the same components. In the drawings: Figure 1 is a schematic diagram of the overall structure of the cutting magnet for a miniaturized particle accelerator according to the present invention; Figure 2 is Figure 1 a schematic diagram of the magnet core structure in Figure 3 is Figure 1 a schematic diagram of the exciting coil structure in Figure 4 is Figure 1 a schematic diagram of the connection between the power connection copper bar and the wire of the exciting coil in Figure 5 is Figure 1 a schematic diagram of the structure of the cooling water pipe assembly in Figure 6 is Figure 1 a schematic diagram of the structure of the shielding fixing assembly in Figure 7 is Figure 1 a schematic diagram of the structure of the coil bracket in Figure 8 is Figure 1 a schematic diagram of the structure of the magnet bracket in

[0017] The reference numerals in the drawings are as follows: 1 - Magnet iron core; 2 - Excitation coil; 201 - Coil body; 202 - Conducting wire; 3 - Electric connection copper bar; 4 - Cooling water pipe assembly; 401 - Main manifold; 402 - Branch water pipe; 5 - Shield fixing assembly; 6 - Coil support assembly; 601 - First support; 602 - Second support; 7 - Magnet support; 8 - Lifting lug. Detailed implementation mode

[0018] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present invention can be more thoroughly understood and the scope of the present invention can be fully conveyed to those skilled in the art.

[0019] The present invention provides a cutting magnet for a miniaturized particle accelerator. By changing the installation method of the coil through the upper and lower structure of the magnet iron core, the magnet support can be designed to be simpler, easier to install and manufacture, saving space and manufacturing costs.

[0020] As Figure 1 shown, the cutting magnet for a miniaturized particle accelerator provided by the present invention includes: a magnet iron core 1 (see Figure 2 ), which is in an upper and lower half structure. A notch groove is provided at the large diameter end of the magnet iron core, and the notch groove is an air gap and the inner wall forms a pole face; An excitation coil 2, as Figure 3 shown, includes a coil body 201 wound into a saddle shape by a plurality of turns of conducting wire, and a plurality of turns of conducting wire 202 at the inlet end and the outlet end of the saddle-shaped coil body are respectively arranged vertically at intervals; the coil body 201 is embedded in the air gap of the magnet iron core 1; An electric connection copper bar 3, as Figure 4 shown, a plurality of turns of conducting wire 202 at the inlet end and the outlet end of the coil body 201 are respectively welded to the electric connection copper bar 3 to connect the plurality of turns of conducting wire 202 in series, and the electric connection copper bar 3 is used for connecting an external cable.

[0021] In the above embodiment, preferably, each turn of conducting wire 202 is made of a copper wire with an inner circle wrapped by an outer square inter-turn insulation, and the copper wire is in a hollow tubular structure to facilitate the passage of cooling water.

[0022] In the above embodiment, preferably, there are two groups of excitation coils 2, and the two groups of excitation coils 2 are arranged oppositely.

[0023] In the above embodiment, preferably, the present invention further includes a cooling water pipe assembly 4; as Figure 5As shown in the figure, the cooling water pipe assembly 4 includes a main header 401 and branch water pipes 402; two main headers 401 are arranged vertically, and a number of branch water pipes 402 are respectively connected to each main header 401; among them, a number of branch water pipes 402 on one main header 401 are respectively connected to a number of turns of wires 202 at the inlet end of the coil body 201; a number of branch water pipes 402 on the other main header 401 are respectively connected to a number of turns of wires 202 at the outlet end of the coil body 201. In practical use, cooling water is introduced into one main header 401, and the cooling water is recovered by the other main header 401.

[0024] In the above embodiment, preferably, the present invention further includes a shielding and fixing assembly 5, as Figure 6 shown, the shielding and fixing assembly 5 is a housing structure that is open at both the top and bottom and is in a C shape. The shielding and fixing assembly 5 covers the large-diameter end of the magnet core 1 and is fixed to the magnet core 1 for shielding the leakage field.

[0025] In the above embodiment, preferably, the present invention further includes a coil support assembly 6; as Figure 7 shown, the coil support assembly includes a first support 601 and a second support 602; the first support 601 is fixedly arranged on the first side of the magnet core 1 for fixing the exciting coil 2; the second support 602 is fixedly arranged on the second side of the magnet core 1 for fixing the exciting coil 2; the main header 401 is fixed on the coil support assembly 6, specifically, fixed on the first support 601.

[0026] In the above embodiment, preferably, the present invention further includes a magnet support 7 (see Figure 8 ); the magnet support 7 is fixed to the bottom of the coil support assembly 6 for supporting the entire cutting magnet device.

[0027] In the above embodiment, preferably, the magnet core 1 is made of the soft magnetic material of pure electrical iron DT4.

[0028] In the above embodiment, preferably, the inter-turn insulation is processed by semi-overlapping wrapping with polyimide and glass ribbon and is formed by vacuum epoxy casting.

[0029] In the above embodiment, preferably, the top of the magnet core 1 has a lifting lug 8, and the lifting lug is used for lifting the upper half of the magnet core.

[0030] During use, the cooling water pipe assembly 4 uses an external cooling device to supply cooling water to the excitation coil. The current-carrying copper busbar 3 is used to transmit current to the excitation coil 2, so that an effective deflection magnetic field is generated in the pole face area of the magnet iron core 1, deflecting the ion beam to the required direction. During installation, since the structure of the magnet iron core 1 is an upper and lower structure, after the magnet bracket is installed in place, the upper half of the magnet iron core 1 is lifted, and the excitation coil 2 can be directly placed in place without disassembling the coil bracket 6, and then the upper half of the magnet iron core is closed. The same applies to disassembly. In this way, the size of the magnet bracket only needs to meet the support strength, and there is no need to make the size very large to ensure the radial stroke of the magnet iron core 1, and both installation and disassembly become relatively easy.

[0031] A cutting magnet for a miniaturized particle accelerator according to an embodiment of the present invention realizes the saving of installation space and manufacturing cost when the required magnetic field strength is not high and it operates directly, overcomes the large installation space and higher cost brought by the commonly used iron core and bracket structures at present, and provides a new design scheme for the development of miniaturized accelerators.

[0032] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention 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 for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A cutting magnet for a miniaturized particle accelerator, characterized in that: include: The magnet core is in a structure of upper and lower halves, wherein a notch groove is provided at the large diameter end of the magnet core, wherein the notch groove is an air gap and the inner wall forms a pole surface; The excitation coil comprises a coil body wound into a saddle shape by a plurality of turns of wire, and the plurality of turns of wire at the inlet end and the outlet end of the saddle-shaped coil body are arranged vertically and spaced apart; the coil body is embedded in the air gap of the magnet core; A power connection copper bar, to which several turns of wire at the inlet and outlet ends of the coil body are respectively welded to connect several turns of wire in series, and the power connection copper bar is used for connecting external cables.

2. The cut magnet according to claim 1, characterized in that: Each turn of the conductor is made of an outer inter-turn insulation wrapped around an inner copper conductor, and the copper conductor is a hollow tubular structure.

3. The cut magnet according to claim 2, characterized in that: There are two groups of excitation coils, and the two groups of excitation coils are arranged opposite to each other.

4. The cut magnet according to claim 2 or 3, characterized in that: Also included is a cooling water pipe assembly; The cooling water pipe assembly includes a main header and a water distribution pipe; The two main collecting pipes are respectively arranged vertically, and each of the main collecting pipes is respectively connected to a plurality of water distribution pipes; Among them, several water distribution pipes on one of the main collecting pipes are respectively connected to several turns of wires at the inlet end of the coil body; several water distribution pipes on another main collecting pipe are respectively connected to several turns of wires at the outlet end of the coil body.

5. The cut magnet according to claim 4, characterized in that: It also includes a shielding and fixing component, which is a C-shaped shell structure with openings on both the top and the bottom. The shielding and fixing component is covered at the large-diameter end of the magnet core and fixed to the magnet core for shielding leakage fields.

6. The cut magnet according to claim 4, characterized in that: Also included is a coil support assembly; The coil support assembly includes a first support and a second support; The first bracket is fixedly disposed on the first side of the magnet core and is used to fix the excitation coil; The second bracket is fixedly disposed on the second side of the magnet core and is used to fix the excitation coil; The main collecting pipe is fixed on the coil support assembly.

7. The cut magnet according to claim 6, characterized in that: Also includes magnet mount; The magnet support is fixed to the bottom of the coil support assembly and is used to support the entire cutting magnet device.

8. The cut magnet according to claim 1, characterized in that: The magnet core is made of electrical pure iron DT4 soft magnetic material.

9. The cut magnet according to claim 2, characterized in that: The inter-turn insulation is semi-lapped with polyimide and glass ribbon and is formed by vacuum epoxy casting.

10. The cut magnet according to claim 1, characterized in that: The top of the magnet core is provided with a lifting lug, and the lifting lug is used to lift the upper half of the magnet core.

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