Acceleration cavity

Abstract

An acceleration cavity is provided with: a housing which has a conductive cylindrical shape and in which divided members, which are divided into a plurality of divided surfaces along a central axis, are provided in a state in which the divided surfaces face each other with a gap therebetween; a plurality of unit sections which are arranged inside the housing so as to be aligned in the axial direction of the central axis of the housing, and which communicate with each other by communicating sections through which the charged particles can pass; and a vacuum manifold connected to the plurality of unit parts via the gap.

Description

Technical Field

[0001] The invention relates to an accelerating cavity. Background Art

[0002] The accelerating cavity generates an accelerating electric field inside by inputting a high frequency, thereby accelerating charged particles such as electrons. As such an accelerating cavity, for example, a structure is known in which a plurality of unit parts are arranged axially along a central axis, and the unit parts are connected to each other through a connecting part (for example, refer to Patent Document 1).

[0003] Previous technical literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 1-107499 Summary of the invention

[0006] Technical issues to be solved by the invention

[0007] In recent years, the following method has been proposed: when manufacturing the above-mentioned accelerating cavity, a plurality of dividing parts are preliminarily formed by dividing surfaces on a plane along the central axis, and the dividing parts are joined together by the dividing surfaces to form the accelerating cavity. In the accelerating cavity manufactured by this method, a structure capable of effectively performing vacuum exhaust in the accelerating cavity is required.

[0008] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an accelerating chamber whose interior can be efficiently evacuated.

[0009] Means for solving technical problems

[0010] The accelerating cavity involved in the present invention comprises: a frame, which is in the shape of a tube with conductivity, and is arranged in a state where a plurality of dividing parts are divided by a planar dividing surface along a central axis and are opposed to each other with a gap along the dividing surface; a plurality of unit parts are arranged inside the frame in an axial direction along the central axis of the frame, and are connected to each other through a connecting part that allows charged particles to pass; and a vacuum manifold, which is connected to the plurality of unit parts via the gap.

[0011] Effects of the Invention

[0012] According to the present invention, it is possible to provide an accelerating chamber whose interior can be efficiently evacuated. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a plan view showing an example of the accelerating cavity according to the first embodiment.

[0014] Figure 2 It means along Figure 1Diagram of the structure of the AA section.

[0015] Figure 3 It means along Figure 2 Figure 2 shows the structure of the BB cross section.

[0016] Figure 4 This is a cross-sectional view showing an example of an accelerating cavity according to the second embodiment.

[0017] Figure 5 It means along Figure 4 Figure 2 shows the structure of the CC cross section.

[0018] Figure 6 This is a cross-sectional view showing an example of an accelerating cavity according to the third embodiment.

[0019] Figure 7 It means along Figure 6 Figure 2 shows the structure of the DD cross section.

[0020] Figure 8 This is a cross-sectional view showing another example of the accelerating cavity according to the third embodiment.

[0021] Fig. 9 It means along Figure 8 Diagram of the structure of the EE cross section. DETAILED DESCRIPTION

[0022] Hereinafter, an embodiment of the accelerating cavity involved in the present invention will be described with reference to the accompanying drawings. In addition, the present invention is not limited to the embodiment. Furthermore, the constituent elements in the following embodiments include components that can be easily replaced by a person skilled in the art or components that are substantially the same.

[0023] Figure 1 It is a plan view showing an example of the accelerating cavity 100 according to the first embodiment. Figure 2 It means along Figure 1 Figure 2 shows the structure of the AA section in FIG. Figure 2 In FIG. 1 , although it is not a cross section, a state in which a hatching line is given on the dividing surface 12 is shown. Figure 3 It means along Figure 2 Figure 2 shows the structure of the BB cross section.

[0024] Figures 1 to 3The acceleration cavity 100 shown generates an accelerating electric field inside by inputting a high frequency, so as to accelerate the charged particles M such as electrons emitted from the radiation source BS. The acceleration cavity 100 and the radiation source BS are used to form an accelerator AC. The accelerator AC is used in various fields such as academic fields such as high-energy physics experiments or radiation light facilities, medical fields such as radiotherapy or inspection, and industrial fields such as non-destructive inspection. In addition, in the following description, when explaining the axial direction of the central axis AX in the direction in the acceleration cavity 100, the radiation source BS side (the side where the charged particles M are incident) is marked as the incident side, and the side opposite to the incident side (the side where the charged particles are emitted) is marked as the emission side.

[0025] like Figures 1 to 3 As shown, the acceleration chamber 100 according to the present embodiment includes a frame 10 , a unit portion 20 , a coupling cavity 30 , and a vacuum manifold 40 .

[0026] The frame 10 is in the shape of a tube having conductivity. The frame 10 is formed in a state where a plurality of split components 11 are joined. The split components 11 have planar split surfaces 12 along the central axis AX. The split components 11 are joined in a state where the split surfaces 12 are opposed to each other. The split components 11 are arranged in a state where a gap 13 is separated between the opposing split surfaces 12. In the present embodiment, a structure in which the frame 10 is split in a lateral direction of the central axis AX along a plane that is orthogonal to the horizontal plane and passes through the central axis AX is used as an example for explanation. The number of divisions of the frame 10 is not limited to two, and may be three or more. The split components 11 have a partially rounded shape that is opposed to each other as a whole. Therefore, local application of voltage is suppressed.

[0027] The unit 20 is formed inside the frame 10. The unit 20 is arranged in an axial direction along the central axis AX of the frame 10. The unit 20 is connected to each other through a connecting portion 22 for passing charged particles. The connecting portion 22 is formed along the central axis AX. The unit 20 accelerates the charged particles by high frequency.

[0028] The coupling cavity 30 connects the adjacent unit parts 20. The coupling cavity 30 propagates high frequency between the adjacent unit parts 20. The coupling cavity 30 is arranged at a position that does not contribute to the acceleration of charged particles. The coupling cavity 30 is arranged outside the unit part 20 in the same direction in the direction orthogonal to the central axis AX. In the first embodiment, all the coupling cavities 30 are arranged above the unit part 20 with respect to the central axis AX.

[0029] The vacuum manifold 40 is a portion that forms a negative pressure when vacuum exhausting the plurality of unit parts 20. The vacuum manifold 40 is connected to a vacuum forming portion 42 such as a vacuum pump via a piping 43. In the present embodiment, the vacuum manifold 40 is, for example, disposed inside the frame 10. The vacuum manifold 40 forms a space and is disposed above each combined cavity 30. The vacuum manifold 40 is connected to the plurality of unit parts 20 via the gap 13 between the dividing parts 11. Each unit part 20 is connected to one vacuum manifold 40. Furthermore, in the present embodiment, the vacuum manifold 40 is connected to the combined cavity 30 via a connecting portion 45. Therefore, the vacuum manifold 40 is connected to the plurality of unit parts 20 via each combined cavity 30. According to this structure, the vacuum manifold 40 and the plurality of unit parts 20 are reliably connected.

[0030] like Figure 2 As shown, in the frame 10, a unit unit portion 21 and a unit connecting portion 23 constituting a part of the unit portion 20 and the connecting portion 22, a unit combining cavity 31 constituting a part of the combining cavity 30, and a unit manifold 41 constituting a part of the vacuum manifold 40 are formed on the dividing surface 12 of each dividing component 11.

[0031] The unit portion 20 is formed by combining the unit unit portions 21 provided in each of the divided components 11. The communication portion 22 is formed by combining the unit communication portions 24 provided in each of the divided components 11. The coupling cavity 30 is formed by combining the unit coupling cavities 31 provided in each of the divided components 11. The vacuum manifold 40 is formed by combining the unit manifolds 41 formed in each of the divided components 11.

[0032] The accelerating cavity 100 involved in this embodiment comprises: a frame 10, which is in the shape of a tube with conductivity and in which a plurality of dividing parts 11 divided into a plane along a central axis AX are arranged in a state where they are opposed to each other with a gap 13 between them along a dividing surface 12 of the plane; a plurality of unit parts 20 are arranged inside the frame 10 in a state where they are arranged in the axial direction of the central axis AX of the frame 10 and are connected to each other via a connecting part 22 that allows charged particles to pass through; and a vacuum manifold 40, which is connected to the plurality of unit parts 20 via the gap 13.

[0033] According to this configuration, in a structure in which the frame 10 is provided with the divided surfaces 12 of the divided members 11 facing each other with the gaps 13 interposed therebetween, the vacuum manifold 40 is connected to the plurality of unit portions 20 via the gaps 13 , so that the interior can be efficiently evacuated.

[0034] In the acceleration chamber 100 according to the present embodiment, the vacuum manifold 40 is connected to the gap 13 of the housing 10 in a direction perpendicular to the central axis AX. With this configuration, the vacuum manifold 40 can be arranged relative to the housing 10 in a direction perpendicular to the central axis AX.

[0035] In the accelerating cavity 100 involved in the present embodiment, all the combined cavities 30 are arranged on the same side in the direction orthogonal to the central axis AX relative to the unit part 20. In this structure, by making the combined cavities 30 biased to the same side in the direction orthogonal to the central axis AX relative to the unit part 20, the direction of the electric field in the direction orthogonal to the central axis AX (up and down direction) is reversed for two combined cavities 30 connected to one unit part 20. As a result, the electric field in the up and down direction is canceled, so that the center of the electric field distribution in the unit part 20 can be suppressed from being biased to the up and down direction. Therefore, the deflection of the charged particle beam can be suppressed.

[0036] The accelerating chamber 100 according to the present embodiment further includes a connecting cavity 30 disposed inside the frame 10 and connecting adjacent unit portions 20, and the connecting cavity 30 is connected to a vacuum manifold 40. According to this structure, the vacuum manifold 40 is connected to the unit portion 20 via the connecting cavity 30, so that the unit portion 20 can be more reliably vacuum-exhausted through the vacuum manifold 40.

[0037] In the accelerating chamber 100 according to the present embodiment, the vacuum manifold 40 is provided inside the housing 10. In this structure, by providing the vacuum manifold 40 inside the housing 10, the number of components can be reduced.

[0038] Next, a second embodiment will be described. Figure 4 FIG. 2 is a cross-sectional view showing an example of an accelerating cavity 200 according to the second embodiment. Figure 4 In FIG. 1 , although it is not a cross section, a hatched state is shown on the dividing surface 112 . Figure 5 It means along Figure 4 Figure 2 shows the structure of the CC cross section.

[0039] like Figure 4 and Figure 5As shown in FIG. 1 , the accelerating cavity 200 according to the second embodiment includes a frame 110, a unit portion 120, a coupling cavity 130, and a vacuum manifold 140. The frame 110 is formed by joining a plurality of split components 111. The split components 111 are joined in a state where split surfaces 112 face each other, and are provided with a gap 113 between the facing split surfaces 112. A plurality of unit portions 120 are formed in a state arranged along the axial direction of the central axis AX inside the frame 110, and are connected to each other through a connecting portion 122. In the accelerating cavity 200 according to the second embodiment, although the marking based on the symbol is omitted, in the frame 110, as in the first embodiment, a unit unit portion and a unit connecting portion constituting a part of the unit portion 120 and the connecting portion 122, a unit connecting cavity constituting a part of the coupling cavity 130, and a unit manifold constituting a part of the vacuum manifold 140 are formed on the split surfaces 112 of each split component 111.

[0040] In the acceleration cavity 200 involved in this embodiment, the coupling cavity 130 and the vacuum manifold 140 are arranged on the opposite side of the unit part 120 in the direction perpendicular to the central axis AX. That is, the following structure is formed: in the direction perpendicular to the central axis AX, the coupling cavity 130 is arranged on one side relative to the unit part 120, and the vacuum manifold 140 is arranged on the other side opposite to the one side relative to the unit part 120. Figure 4 In the illustrated example, the coupling cavity 130 is disposed on the upper side of the unit portion 120 , and the vacuum manifold 140 is disposed on the lower side of the unit portion 120 .

[0041] In this structure, the vacuum manifold 140 and the cell unit 120 are connected via the gap 113. Therefore, the cell unit 120 can be vacuum-exhausted through the gap 113 by the vacuum manifold 140. Therefore, the cell unit 120 can be vacuum-exhausted efficiently.

[0042] Next, a third embodiment will be described. Figure 6 FIG. 1 is a cross-sectional view showing an example of an accelerating cavity 300 according to the third embodiment. Figure 6 In FIG. 1 , although it is not a cross section, a hatched state is shown on the dividing surface 212 . Figure 7 It means along Figure 6 Figure 2 shows the structure of the DD cross section.

[0043] like Figure 6 and Figure 7As shown, the accelerating cavity 300 involved in the third embodiment includes a frame 210, a unit part 220, a combined cavity 230 and a vacuum manifold 240. The frame 210 is formed in a state where a plurality of split components 211 are joined. The split components 211 are joined in a state where the split surfaces 212 face each other, and are arranged in a state where a gap 213 is spaced between the facing split surfaces 212. In addition, the gap 213 is sealed by welding, bonding or a sealant, etc., except for the vacuum manifold 240 and the connecting part 222 provided outside the frame 210. A plurality of unit parts 220 are formed in a state where they are arranged in the axial direction of the central axis AX inside the frame 210, and are connected to each other through the connecting part 222. In addition, in the acceleration cavity 300 involved in the third embodiment, although the notation based on symbols is omitted, similarly to the above-mentioned embodiments, in the frame 210, a unit unit portion and a unit connecting portion constituting a part of the unit portion 220 and the connecting portion 222, a unit combined cavity constituting a part of the combined cavity 230, and a unit manifold constituting a part of the vacuum manifold 240 are formed on the dividing surface 212 of each dividing component 211.

[0044] like Figure 6 and Figure 7 As shown, in the acceleration chamber 300 according to the third embodiment, the vacuum manifold 240 is provided outside the frame 210. That is, the vacuum manifold 240 and the frame 210 are provided as separate components. Thus, the degree of freedom in the arrangement of the vacuum manifold 240 is improved.

[0045] exist Figure 6 and Figure 7 In the example shown, the vacuum manifold 240 is provided inside a manifold forming member 242 disposed laterally in the axial direction of the central axis AX with respect to the frame 210. Figure 7 As shown, the manifold forming member 242 has, for example, an arc-shaped cross section, but is not limited to this structure, and may also have other shapes such as a rectangular shape or a triangular shape.

[0046] like Figure 6 and Figure 7 As shown, the frame 210 has an exhaust hole 214. The exhaust hole 214 is disposed at a position of the frame 210 away from each unit portion 220. The exhaust hole 214 is formed in a direction intersecting the dividing surface 212. The exhaust hole 214 communicates between the gap 213 and the vacuum manifold 240.

[0047] Figure 8 FIG. 2 is a cross-sectional view showing another example of the accelerating cavity according to the third embodiment. Figure 8 In FIG. 1 , although it is not a cross section, a hatched state is shown on the dividing surface 212 . Fig. 9 It means along Figure 8FIG. 2 is a diagram showing the structure of the EE cross section in FIG. 2. At a point where the vacuum manifold 240A (manifold forming member 242A) is arranged below the frame 210, Figure 8 and Fig. 9 The acceleration cavity 300A shown has a different structure from the acceleration cavity 300A. In this structure, the vacuum manifold 240A is connected to the unit portion 220 via the gap 213.

[0048] In the accelerating chamber 300, 300A according to the present embodiment, the vacuum manifold 240 is provided outside the housing 210. This improves the degree of freedom in arranging the vacuum manifold 240.

[0049] Furthermore, in the accelerating cavity 300, the frame 210 has an exhaust hole 214, which is formed in a direction intersecting the dividing surface 212 at a position separated from the plurality of unit portions 220 and connects the gap 213 with the vacuum manifold 240 provided outside the frame 210. In this structure, the unit portions 220 can be effectively vacuum-exhausted through the exhaust hole 214 by the vacuum manifold 240.

[0050] As described above, the accelerating cavity involved in the first embodiment of the present invention comprises: a frame 10, which is in the shape of a tube having conductivity, and in which a plurality of dividing parts 11 divided into a plane along a central axis AX are arranged in a state opposite to each other with a gap 13 separated therefrom along a dividing surface 12 of the plane; a plurality of unit parts 20 are arranged inside the frame 10 in a state arranged in the axial direction of the central axis AX of the frame 10, and are connected to each other through a connecting part 22 that allows charged particles to pass through; and a vacuum manifold 40, which is connected to the plurality of unit parts 20 via the gap 13.

[0051] According to this configuration, in a structure in which the frame 10 is provided with the divided surfaces 12 of the divided members 11 facing each other with the gaps 13 interposed therebetween, the vacuum manifold 40 is connected to the plurality of unit portions 20 via the gaps 13 , so that the interior can be efficiently evacuated.

[0052] The accelerating cavity according to the second aspect of the present invention is the accelerating cavity according to the first aspect, in which the vacuum manifold 40 is connected to the gap 13 of the frame 10 from a direction perpendicular to the central axis AX.

[0053] According to this configuration, the vacuum manifold 40 can be arranged with respect to the housing 10 in a direction perpendicular to the central axis AX.

[0054] The accelerating cavity involved in the third embodiment of the present invention is further provided with a connecting cavity 30 which is arranged inside the frame 10 and connects adjacent unit parts 20 in the accelerating cavity involved in the first embodiment or the second embodiment, and all the connecting cavities 30 are arranged on the same side relative to the unit parts 20 in a direction orthogonal to the central axis AX.

[0055] In this structure, by biasing the coupling cavity 30 to the same side in the direction perpendicular to the central axis AX as the unit portion 20, the center of the electric field distribution in the direction perpendicular to the central axis AX can be made to coincide with the central axis AX. Therefore, the deflection of the charged particle beam can be suppressed.

[0056] The accelerating cavity according to the fourth aspect of the present invention is the accelerating cavity according to the third aspect in which the coupling cavity 30 is connected to the vacuum manifold 40 .

[0057] According to this structure, the vacuum manifold 40 is connected to the unit portion 20 via the coupling cavity 30 , so the unit portion 20 can be more reliably vacuum-exhausted by the vacuum manifold 40 .

[0058] The accelerating cavity according to the fifth aspect of the present invention is the accelerating cavity according to the third aspect, in which the coupling cavity 130 and the vacuum manifold 140 are arranged on the opposite side of the unit portion 120 in a direction perpendicular to the central axis AX.

[0059] In this structure, the vacuum manifold 140 and the cell unit 120 are connected via the gap 113. Therefore, the cell unit 120 can be vacuum-exhausted through the gap 113 by the vacuum manifold 140. Therefore, the cell unit 120 can be vacuum-exhausted efficiently.

[0060] An accelerating cavity according to a sixth aspect of the present invention is the accelerating cavity according to any one of the first to fifth aspects, wherein the vacuum manifold 40 is provided inside the housing 10 .

[0061] In this structure, by providing the vacuum manifold 40 inside the housing 10 , the number of components can be reduced.

[0062] An accelerating cavity according to a seventh aspect of the present invention is the accelerating cavity according to any one of the first to fifth aspects, wherein the vacuum manifold 240 is provided outside the housing 210 .

[0063] This improves the degree of freedom in arranging the vacuum manifold 240 .

[0064] The accelerating cavity involved in the 8th embodiment of the present invention is the accelerating cavity involved in the 7th embodiment, wherein the frame 210 has an exhaust hole 214, which is formed in a direction intersecting the dividing surface 212 at a position separated from the plurality of unit portions 220 and connects the gap 213 with the vacuum manifold 240 arranged outside the frame 210.

[0065] In this structure, the unit portion 220 can be efficiently vacuum-exhausted through the exhaust hole 214 by the vacuum manifold 240 .

[0066] Explanation of symbols

[0067] 10, 110, 210-frame,

[0068] 11, 111-dividing parts,

[0069] 12, 112, 212-dividing surface,

[0070] 13, 113, 213 - gap,

[0071] 20, 120, 220-unit,

[0072] 21-Unit unit,

[0073] 22, 45, 122-connecting part,

[0074] 23, 24-Unit connection part,

[0075] 30, 130-combined cavity,

[0076] 31-unit combined cavity,

[0077] 40, 140, 240 - Vacuum manifold,

[0078] 41-unit manifold,

[0079] 42- vacuum forming part,

[0080] 43-Piping,

[0081] 100, 200, 300, 300A-acceleration cavity,

[0082] 214- Exhaust hole,

[0083] 242-manifold forming component,

[0084] AC-Accelerator,

[0085] AX-center axis,

[0086] BS-ray source,

[0087] M-charged particle.

Claims

1. An accelerating cavity, comprising: The frame is in the shape of a tube having conductivity, and is provided with a plurality of split parts divided by a plane along the central axis in a state where the split parts are opposed to each other with a gap therebetween along the split plane of the plane; A plurality of unit parts are arranged inside the frame in an axial direction along the central axis of the frame, and are connected to each other via a connecting part through which charged particles can pass; and The vacuum manifold is connected to the plurality of unit portions via the gaps.

2. The accelerating cavity according to claim 1, wherein: The vacuum manifold is connected to the gap of the frame from a direction perpendicular to the central axis.

3. The accelerating cavity according to claim 1, further comprising: The combined cavity is arranged inside the frame and connects the adjacent unit parts. All of the coupling cavities are arranged on the same side of the unit portion in a direction orthogonal to the central axis.

4. The accelerating cavity according to claim 3, wherein: The combining cavity is connected to the vacuum manifold.

5. The accelerating cavity according to claim 3, wherein: The coupling cavity and the vacuum manifold are arranged on the opposite side of the unit portion in a direction perpendicular to the central axis.

6. The accelerating cavity according to claim 1, wherein: The vacuum manifold is disposed inside the frame.

7. The accelerating cavity according to claim 1, wherein: The vacuum manifold is arranged outside the frame.

8. The accelerating cavity according to claim 7, wherein: The frame has an exhaust hole formed in a direction intersecting the dividing surface at a position separated from the plurality of unit portions and connecting the gap with the vacuum manifold provided outside the frame.

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