Acceleration cavity

Abstract

The acceleration cavity according to the present invention is provided with: a frame body having a conductive cylindrical shape and provided with divided members divided into a plurality of sections on a plane along a central axis so that divided surfaces along the plane face each other with a gap therebetween; a plurality of unit parts 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 parts through which the charged particles can pass; and a switching member that is disposed in the gap of the housing, is movable along the plane within the gap, and switches the magnitude of an electric field that accelerates the charged particles by the movement.

Description

Technical Field

[0001] This invention relates to an acceleration cavity. Background Technology

[0002] An accelerating cavity generates an accelerating electric field inside by receiving a high-frequency wave input, thereby accelerating charged particles such as electrons. As such an accelerating cavity, a structure is known to be provided with multiple unit sections arranged axially along a central axis, and the unit sections are connected to each other through a connecting section (for example, see Patent Document 1).

[0003] Previous technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 1-107499 Summary of the Invention

[0006] The technical problem to be solved by the invention

[0007] For the accelerating cavity described above, a structure is proposed that can switch the energy of charged particles by changing the magnitude of the accelerating electric field. For this accelerating cavity, a structure capable of switching the energy of charged particles without using complex mechanisms is required.

[0008] The present invention was made in view of the above, and its object is to provide an accelerating cavity that can switch the energy of charged particles without using a complex mechanism.

[0009] means for solving technical problems

[0010] The accelerating cavity of the present invention comprises: a frame having a conductive cylindrical shape and being arranged in a state in which multiple segmented parts are divided along a plane along a central axis and are positioned opposite each other with gaps between them along the segmented surfaces of the plane; multiple unit parts arranged inside the frame in a state arranged along the axial direction of the central axis of the frame and interconnected with each other through a connecting part that allows charged particles to pass through; and a switching member disposed in the gap of the frame and movable along the plane within the gap, thereby switching the magnitude of the electric field that accelerates the charged particles by means of the movement.

[0011] Invention Effects

[0012] According to the present invention, an accelerating cavity that can switch the energy of charged particles without using a complex mechanism can be provided. Attached Figure Description

[0013] Figure 1 This is a top view showing an example of an acceleration cavity involved in the implementation method.

[0014] Figure 2 It means along Figure 1 The diagram shows the structure of section AA in the diagram.

[0015] Figure 3 It means along Figure 2 A diagram of the structure of section BB in the diagram.

[0016] Figure 4 This is a diagram illustrating a structural example that allows the switching component to move.

[0017] Figure 5 This is a diagram illustrating a structural example that allows the switching component to move.

[0018] Figure 6 This is a diagram illustrating a structural example that allows the switching component to move.

[0019] Figure 7 This is a diagram illustrating a structural example that allows the switching component to move.

[0020] Figure 8 This is a diagram illustrating a structural example that allows the switching component to move.

[0021] Figure 9 This is a diagram illustrating a structural example that allows the switching component to move.

[0022] Figure 10 This is another example of an accelerating cavity.

[0023] Figure 11 This is a diagram illustrating one example of how an acceleration cavity can be used.

[0024] Figure 12 This is a diagram illustrating one example of how an acceleration cavity can be used. Detailed Implementation

[0025] Hereinafter, embodiments of the accelerating cavity according to the present invention will be described with reference to the accompanying drawings. However, the present invention is not limited to these embodiments. Furthermore, the constituent elements in the following embodiments include components that are readily replaceable or substantially identical to those skilled in the art.

[0026] Figure 1 This is a top view showing an example of the acceleration cavity 100 according to this embodiment. Figure 2 It means along Figure 1 A diagram of the structure of section AA in the image. Additionally, in... Figure 2 In the middle, it is represented by a state that is not a cross section but is marked with a shaded line on the dividing surface 12. Figure 3 It means along Figure 2 A diagram of the structure of section BB in the diagram.

[0027] Figures 1 to 3The accelerating cavity 100 shown generates an accelerating electric field inside by inputting a high-frequency wave from the high-frequency wave input unit WI, thereby accelerating charged particles M, such as electrons, emitted from the radiation source BS. The accelerating cavity 100 and the radiation source BS are used to construct an accelerator AC. The accelerator AC can be used in various fields, such as academic fields like high-energy physics experiments or radiation facilities, medical fields like radiation therapy or examinations, and industrial fields like non-destructive testing. Furthermore, in the following description, when explaining the axial direction of the central axis AX within the accelerating cavity 100, the side of the radiation source BS (the side where charged particles M are injected) is marked as the injection side or rear, and the opposite side (the side where charged particles are emitted) is marked as the emission side or front. Also, when the accelerating cavity 100 is arranged in a facility or the like, the vertical direction is marked as the up-down direction, and the direction orthogonal to the up-down direction when viewing the front from the rear of the central axis AX is marked as the left-right direction.

[0028] like Figures 1 to 3 As shown, the acceleration cavity 100 according to this embodiment includes a frame 10, a unit 20, a connecting cavity 30, a vacuum manifold 40, and a switching component 50.

[0029] The frame 10 is in the shape of a conductive cylinder. The frame 10 is formed with a plurality of segmented members 11 joined together. Each segmented member 11 has a planar dividing surface 12 along the central axis AX. Each segmented member 11 is joined with its dividing surfaces 12 facing each other. Each segmented member 11 is arranged with a gap 13 between the opposing dividing surfaces 12. In this embodiment, the structure of the frame 10 divided along a plane orthogonal to the horizontal plane and passing through the central axis AX in a left-right direction is described as an example. The number of segments in the frame 10 is not limited to two; it can be three or more. The segmented members 11 have rounded corners in their opposing portions. Therefore, localized voltage application can be suppressed.

[0030] Unit sections 20 are formed inside the frame 10. The unit sections 20 are arranged in a configuration along the central axis AX of the frame 10. The unit sections 20 are interconnected via connecting sections 22 that allow charged particles to pass through. The connecting sections 22 are formed along the central axis AX. The unit sections 20 accelerate charged particles using high-frequency waves.

[0031] The connecting cavity 30 connects adjacent unit portions 20 to each other. The connecting cavity 30 propagates high-frequency waves between adjacent unit portions 20. The connecting cavity 30 is positioned at a location that does not contribute to the acceleration of charged particles. The connecting cavity 30 is positioned outward in the same direction orthogonal to the central axis AX relative to the unit portion 20. In this embodiment, with the central axis AX as a reference, all connecting cavities 30 are positioned above the unit portions 20. The connecting cavity 30 has a first space portion 31 connected to the unit portion 20, a second space portion 32 positioned radially outward relative to the first space portion 31 and separated from the central axis AX, and a connecting portion 33 connecting the first space portion 31 and the second space portion 32 radially upward. The first space portion 31, the second space portion 32, and the connecting portion 33 are, for example, cylindrical about an axis extending in the vertical direction. The first space portion 31, the second space portion 32, and the connecting portion 33 may also be prismatic or the like. Compared with the first space portion 31 and the second space portion 32, the diameter of the connecting portion 33 is smaller in the vertical direction.

[0032] The vacuum manifold 40 is the part that creates negative pressure when vacuum exhausting the multiple unit sections 20. The vacuum manifold 40 is connected to a vacuum forming part 42, such as a vacuum pump, via a piping 43. In this embodiment, the vacuum manifold 40 is, for example, disposed inside the frame 10. The vacuum manifold 40 forms a space and is positioned above each connecting cavity 30. The vacuum manifold 40 is connected to the multiple unit sections 20 via gaps 13 between the dividing members 11. Each unit section 20 is connected to one vacuum manifold 40. Furthermore, in this embodiment, the vacuum manifold 40 communicates with the connecting cavity 30 via a connecting portion 45. Therefore, the vacuum manifold 40 is connected to the second space portion 32 of each connecting cavity 30, and is connected from the second space portion 32 to the multiple unit sections 20 via the connecting cavity 30. According to this structure, the vacuum manifold 40 is reliably connected to the multiple unit sections 20.

[0033] like Figure 2 As shown, in the frame 10, on the dividing surface 12 of each dividing member 11, there are a unit unit part 21 and a unit connecting part 23 that constitute part of the unit part 20 and the connecting part 22, a unit connecting cavity 35 that constitutes part of the connecting cavity 30, and a unit manifold 41 that constitutes part of the vacuum manifold 40.

[0034] The unit section 20 is formed by combining the unit unit sections 21 disposed on each of the segmented components 11. The connecting section 22 is formed by combining the unit connecting sections 24 disposed on each of the segmented components 11. The connecting cavity 30 is formed by combining the unit connecting cavities 35 disposed on each of the segmented components 11. The vacuum manifold 40 is formed by combining the unit manifolds 41 formed on each of the segmented components 11.

[0035] A switching component 50 is disposed within the gap 13 of the frame 10. The switching component 50 is movable within the gap 13 along a plane passing through the central axis AX. In this embodiment, the switching component 50 is movable within the gap 13 along a plane passing through the central axis AX and orthogonal to the left-right direction. The switching component 50 switches the magnitude of the electric field that accelerates charged particles by moving. By switching the magnitude of the electric field with the switching component 50, the energy of the charged particles can be switched.

[0036] The switching component 50 is formed using a conductor such as metal. The switching component 50 is, for example, a plate with a thickness thinner than the gap 13. The switching component 50 is configured to enter and exit the connecting cavity 30. When the switching component 50 is configured to enter the interior of the connecting cavity 30, the electromagnetic field of the connecting cavity 30 can be cut off. The switching component 50 can move between a retracted position P1 (retracting from the connecting cavity 30) and a cut-off position P2 (entering the interior of the connecting cavity 30). In this embodiment, the cut-off position P2 can be set at the position where it enters the connecting portion 33 of the connecting cavity 30.

[0037] The switching component 50 is connected to the transmission mechanism 51. The transmission mechanism 51 is connected to the outside of the housing 10. The transmission mechanism 51 transmits the driving force generated outside the housing 10 to the switching component 50. The driving force transmitted to the switching component 50 can be generated manually by an operator or by a drive source such as a motor.

[0038] Figures 4 to 9 This is a diagram illustrating a structural example of moving the switch component 50. Figure 4 , Figure 6 and Figure 8 It is a top view. Figure 5 , Figure 7 and Figure 9 It means along Figure 1 A diagram of the structure of section AA.

[0039] exist Figure 4 and Figure 5In the example shown, the switch member 50 is rotated around a rotation axis BX orthogonal to the central axis AX. The rotation axis BX is arranged in the left-right direction. In this example, the transmission mechanism 51A is formed as a rod, extending from the switch member 50 through the frame 10 along the rotation axis BX to the outside of the frame 10. Thus, the transmission mechanism 51A extends in a direction perpendicular to the plane along the central axis AX. In addition, a bearing or the like with a sealing mechanism can be provided at the part of the transmission mechanism 51A that penetrates the frame 10 to maintain a vacuum state inside the frame 10. Furthermore, it is also possible to have a structure that allows the switch member 50 to rotate from the outside of the frame 10 through a non-contact method such as magnetic coupling. A rotating part 52A is provided on the outside of the frame 10 to rotate the transmission mechanism 51A. The rotating part 52A is, for example, a motor device. Alternatively, the rotating part 52A can also be a structure in which the operator manually rotates the transmission mechanism 51A.

[0040] The transmission mechanism 51A is rotated by the rotating part 52A, thereby causing the switching component 50 to rotate about the rotating shaft BX. The switching component 50 rotates along a plane including the central axis AX between a retracted position P1A (retracting from the engagement cavity 30) and a cut-off position P2B (entering the engagement cavity 30). The rotation range of the switching component 50 can be adjusted by using an encoder or other means to regulate the rotation based on the rotating part 52A, or by using a physical mechanism such as a limit switch.

[0041] exist Figure 6 and Figure 7 In the example shown, the switch member 50 is slidable along the central axis AX. In this example, the transmission mechanism 51B has a rotating member 53B, a rod-shaped member 54B, and a support member 55B. The rotating member 53B is formed in an L-shape extending from its base end in two directions (here, for example, left-right and front-back directions). The rotating member 53B rotates about a rotation axis CX passing through its base end in the vertical direction. In the rotating member 53B, for example, the front end of the portion extending in the left-right direction is connected to the switch member 50. In the rotating member 53B, for example, the front end of the portion extending in the front-back direction is connected to the rod-shaped member 54B. The rod-shaped member 54B extends to the outside of the frame 10 in the left-right direction. Thus, the transmission mechanism 51B extends in a direction perpendicular to the plane along the central axis AX.

[0042] A drive unit 52B is provided on the outside of the frame 10 to move the rod-shaped member 54B in the left-right direction. The drive unit 52B is, for example, a bellows mechanism. By extending or retracting the bellows, the rod-shaped member 54B can be moved in the left-right direction. Alternatively, other drive mechanisms such as ball screw mechanisms or cylinder mechanisms can be used instead of bellows mechanisms as the drive unit 52B.

[0043] By stretching the bellows in the drive unit 52B, the rod-shaped member 54B moves to the right. If the rod-shaped member 54B moves to the right, the rotating member 53B rotates clockwise around the rotation axis CX when viewed from above. At this time, the front end of the portion extending left and right from the base moves forward. Therefore, the switch member 50 moves forward.

[0044] By contracting the bellows in the drive section 52B, the rod-shaped member 54B moves to the left. If the rod-shaped member 54B moves to the left, the rotating member 53B rotates counterclockwise around the rotation axis CX when viewed from above. At this time, the front end of the portion extending left and right from the base moves rearward. Therefore, the switch member 50 moves rearward.

[0045] Thus, the switching component 50 can slide in the front-to-back direction via the transmission mechanism 51B and the drive unit 52B. Figure 6 and Figure 7 In the example, the position where the switch component 50 moves forward is considered the retracted position P1B, and the position where the switch component 50 moves backward is considered the cut-off position P2B. Alternatively, the position where the switch component 50 moves forward can be considered the cut-off position P2B, and the position where the switch component 50 moves backward can be considered the retracted position P1B.

[0046] exist Figure 8 and Figure 9 In the example shown, the switch member 50 is slidable along the central axis AX. In this example, the transmission mechanism 51C has a wire-like member 53C and a guide member 54C. One end of the wire-like member 53C (the switch-side end) is connected to the switch member 50. The wire-like member 53C can be a member that is rigid in the length direction and can deform in a direction orthogonal to the length direction, such as a metal wire. The wire-like member 53C is configured, for example, to be pulled forward from the switch member 50, bent to the left by the guide member 54C, and extend its front end to the outside of the frame 10. The guide member 54C can be a tubular member, such as a tube. The wire-like member 53C is arranged to pass through the interior of the guide member 54C. Thus, the transmission mechanism 51C extends in a direction perpendicular to the plane along the central axis AX.

[0047] A drive unit 52C is provided on the outside of the frame 10 to move the linear member 53C in the left-right direction. The drive unit 52C is connected to the other end (drive side end) of the linear member 53C. Similar to the drive unit 52B described above, the drive unit 52C is, for example, a bellows mechanism. By extending and retracting the bellows, the linear member 53C can be moved in the left-right direction. Alternatively, other drive mechanisms such as ball screw mechanisms or cylinder mechanisms can be used instead of bellows mechanisms as the drive unit 52C.

[0048] By stretching the bellows in the drive section 52C, the drive-side end of the linear member 53C is pulled to the right. The linear member 53C is bent by the guide member 54C and its switch-side end is arranged in the front-rear direction. Therefore, by pulling the drive-side end of the linear member 53C to the right, the switch-side end moves forward. As a result, the switch member 50 moves forward.

[0049] By contracting the bellows in the drive section 52C, the drive-side end of the linear member 53C is pushed to the left. The linear member 53C is bent by the guide member 54C and its switch-side end is arranged in the front-rear direction. Therefore, by pushing the drive-side end of the linear member 53C to the left, the switch-side end moves rearward. As a result, the switch member 50 moves rearward.

[0050] Thus, the switching component 50 can slide in the front-to-back direction via the transmission mechanism 51C and the drive unit 52C. Figure 8 and Figure 9 In the example, with Figure 6 and Figure 7 Similarly, in the example shown, the position where the switch component 50 moves forward is considered the retracted position P1C, and the position where the switch component 50 moves backward is considered the cut-off position P2C. Alternatively, the position where the switch component 50 moves forward can be considered the cut-off position P2C, and the position where the switch component 50 moves backward can be considered the retracted position P1C.

[0051] Figure 10 This is another example of an accelerating cavity 100. (See diagram.) Figure 10 As shown, in the portion where the switch member 50 is disposed within the gap 13, a moving gap 14 can be provided in at least a portion of the movable range of the switch member 50. The moving gap 14 is the portion where the distance between the dividing surfaces 12 is greater than the gap 13. By providing the moving gap 14, interference between the switch member 50 and the dividing surfaces 12 of the frame 10 can be suppressed.

[0052] Figure 11 and Figure 12 This diagram illustrates an example of how the acceleration cavity 100 is used. (See diagram below.) Figure 11 As shown, when the switch component 50 is positioned in the retracted position P1, the high-frequency wave input from the high-frequency wave input section WI propagates to all the unit sections 20. Therefore, the charged particles M that are emitted from the ray source BS and enter the acceleration cavity 100 are accelerated in all the unit sections 20 they pass through before being emitted.

[0053] In contrast, such as Figure 12As shown, when the switch member 50 is positioned in the cut-off position P2, the high-frequency wave input from the high-frequency wave input section WI is cut off at the cut-off position P2. In the acceleration cavity 100, no high-frequency wave propagates in the unit section 20 in front of the cut-off position P2. Therefore, charged particles M that enter the acceleration cavity 100 after being emitted from the radiation source BS are accelerated in the unit section 20 through which the high-frequency wave propagates, but are not accelerated and emitted in the unit section 20 where the high-frequency wave does not propagate. At this time, the energy of the charged particles M is lower than when the switch member 50 is positioned in the retraction position P1. Thus, by switching the energy of the charged particles M, the acceleration cavity 100 can be widely used in inspection devices, treatment devices, etc.

[0054] As described above, according to a first aspect of the present invention, an acceleration cavity is provided, comprising: a frame 10 having a conductive cylindrical shape and having multiple dividing parts 11 divided along a plane along the central axis AX, which are arranged opposite each other with a gap 13 between them along the dividing surface 12 of the plane; multiple unit parts 20 arranged inside the frame 10 in a direction along the axial direction of the central axis AX of the frame 10 and interconnected by a connecting part 22 that allows charged particles to pass through; and a switching member 50 disposed in the gap 13 of the frame 10, which is movable along a plane passing through the central axis AX within the gap 13, and which switches the magnitude of the electric field that accelerates the charged particles by moving.

[0055] According to this structure, in the frame 10 which is set with the dividing surfaces 12 of the divided components 11 facing each other with gaps 13 between them, the energy of the charged particles M can be easily switched by moving the switching component 50 using the gaps 13 without using a complicated mechanism.

[0056] The acceleration cavity according to the second aspect of the present invention, in the first aspect, further includes: a connecting cavity 30 disposed inside the frame 10, such that adjacent unit parts 20 are connected to each other, and a switch member 50 is configured to enter and exit the connecting cavity 30.

[0057] According to this structure, the switching component 50 is configured as an input / output cavity, thus enabling effective switching of the propagation and interruption of high-frequency waves.

[0058] In the third aspect of the present invention, the acceleration cavity is in the second aspect, in which all the combined cavities 30 are arranged on the same side in a direction orthogonal to the central axis AX relative to the unit portion 20.

[0059] According to this structure, by offsetting the combined cavity 30 relative to the unit portion 20 on the same side in a direction orthogonal to the central axis AX, the center of the electric field distribution in the direction orthogonal to the central axis AX can be aligned with the central axis AX. Therefore, the deflection of the charged particle beam can be suppressed.

[0060] In the second embodiment, the acceleration cavity according to the fourth aspect of the present invention has a first space portion 31 connected to the unit portion 20, a second space portion 32 disposed relative to the first space portion 31 at a position separated radially outward relative to the central axis AX, and a connecting portion 33 connecting the first space portion 31 and the second space portion 32 radially, and the switch member 50 is configured to enter and exit the connecting portion 33.

[0061] According to this structure, the switching component 50 is configured as a connection part 33 for entering and exiting the cavity 30, thus enabling effective switching of the propagation and interruption of high-frequency waves.

[0062] In the fifth aspect of the present invention, the acceleration cavity is connected to the vacuum manifold 40 via the second space portion 32 of the cavity 30 in the first aspect.

[0063] According to this structure, the vacuum manifold 40 is connected to the unit section 20 via the connecting cavity 30, thus enabling more reliable vacuum exhaust of the unit section 20 through the vacuum manifold 40.

[0064] In the sixth aspect of the present invention, the acceleration cavity has, in the first to fifth aspects, a moving gap 14 in at least a portion of the movable range of the switch member 50, such that the distance between the dividing surfaces 12 is greater than the gap 13.

[0065] According to this structure, by setting the movement gap 14, interference between the switch component 50 and the dividing surface 12 of the frame 10 can be suppressed.

[0066] The acceleration cavity according to the seventh aspect of the present invention, in any one of the first to sixth aspects, further includes: a transmission mechanism 51 that transmits the driving force generated outside the frame 10 to the switching member 50.

[0067] According to this structure, by providing a transmission mechanism 51, the switch component 50 can be moved from the outside of the frame 10.

[0068] In the seventh embodiment, the acceleration cavity involved in the eighth embodiment of the present invention has a transmission mechanism 51 extending in a direction perpendicular to the plane.

[0069] According to this structure, the transmission mechanism 51 extends in a direction perpendicular to the plane, so that driving force can be properly transmitted in any case, such as when the switch member 50 is rotated or when it is slid.

[0070] In any of the first to seventh embodiments of the present invention, the acceleration cavity of the ninth embodiment of the present invention transmits driving force by means of a transmission mechanism 51 that causes the switching member 50 to rotate around a rotation axis BX in a direction orthogonal to the central axis AX.

[0071] According to this structure, the switching component 50 can be moved by the transmission mechanism 51 in such a way that it rotates around the rotation axis BX, which is orthogonal to the central axis AX.

[0072] In any of the first to seventh embodiments of the present invention, the acceleration cavity of the tenth embodiment of the present invention transmits driving force by means of the transmission mechanism 51 in such a way that the switching member 50 slides along the direction of the central axis AX.

[0073] According to this structure, the switch component 50 can be moved by the transmission mechanism 51 in a sliding manner along a direction orthogonal to the central axis AX.

[0074] In the above embodiment, a structure with one switch component 50 was described as an example, but the embodiment is not limited to this structure. Multiple switch components 50 may be provided. In this case, multiple switch components 50 can move independently and can be configured to enter and exit different connecting cavities 30.

[0075] Symbol Explanation

[0076] 10-Frame, 11-Dividing component, 12-Dividing surface, 13-Gap, 14-Moving gap, 20-Unit section, 21-Unit unit section, 22, 45-Connecting section, 23, 24-Unit connecting section, 30-Connecting cavity, 31-First space section, 32-Second space section, 33-Connecting section, 35-Unit connecting cavity, 40-Vacuum manifold, 41-Unit manifold, 42-Vacuum forming section, 43-Pipeline, 50-Switch component, 51, 51A, 51B, 51 C - Transmission mechanism, 52A - Rotating part, 52B, 52C - Driving part, 53B - Rotating component, 53C - Linear component, 54B - Rod-shaped component, 54C - Guiding component, 55B - Supporting component, 100 - Acceleration cavity, AC - Accelerator, AX - Central axis, BS - X-ray source, BX, CX - Rotating axis, M - Charged particle, P1, P1A, P1B, P1C - Retreat position, P2, P2A, P2B, P2C - Cut-off position, WI - High-frequency wave input part.

Claims

1. An accelerating cavity, comprising: The frame is in the shape of a conductive cylindrical part and is divided into multiple segments along a plane along the central axis, with the segments facing each other with gaps along the dividing surfaces of the plane. Multiple unit sections are arranged inside the frame in a manner aligned along the central axis of the frame and interconnected through connecting sections that allow charged particles to pass through; and A switching component, disposed in the gap of the frame, is movable along the plane within the gap, thereby switching the magnitude of the electric field that accelerates the charged particles.

2. The acceleration cavity according to claim 1, further comprising: The cavity is located inside the frame, allowing adjacent unit sections to communicate with each other at a position offset relative to the central axis. The switching component is configured to enter and exit the combined cavity.

3. The accelerating cavity according to claim 2, wherein, All of the combined cavities are arranged on the same side in a direction orthogonal to the central axis relative to the unit portion.

4. The acceleration cavity according to claim 2, wherein, The combined cavity includes: a first space portion connected to the unit portion, a second space portion disposed relative to the first space portion at a position radially outward relative to the central axis, and a connecting portion connecting the first space portion and the second space portion radially. The switch component is configured to enter and exit the connection portion.

5. The acceleration cavity according to claim 4, further comprising: The vacuum manifold is connected to the plurality of the unit sections via the gap. The second space portion of the combined cavity is connected to the vacuum manifold.

6. The accelerating cavity according to claim 1, wherein, The frame has a movement gap in at least a portion of the movable range of the switch component, such that the distance between the dividing surfaces is greater than the gap.

7. The accelerating cavity according to claim 1, further comprising: The transmission mechanism transmits the driving force generated outside the frame to the switching component.

8. The accelerating cavity according to claim 7, wherein, The transmission mechanism extends in a direction perpendicular to the plane.

9. The accelerating cavity according to claim 7, wherein, The transmission mechanism transmits the driving force by causing the switching component to rotate around a rotation axis orthogonal to the central axis.

10. The accelerating cavity according to claim 7, wherein, The transmission mechanism transmits the driving force in such a way that the switching component slides along the central axis.

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