A test bench for RF parameters of a side-coupled standing wave accelerator tube

Abstract

This invention relates to a test bench for the radio frequency parameters of a side-coupled standing wave accelerator tube (SSB). The bench includes an operating platform, an optical panel, a perturbation measurement pulley system, a pressure adjustment assembly, an accelerator tube placement component, and a probe testing assembly. The optical panel is mounted on the operating platform, and the accelerator tube placement component is connected to the side of the optical panel away from the operating platform. The perturbation measurement pulley system is located on both sides of the accelerator tube placement component, and nylon wires with perturbation elements are mounted on it. The probe testing assembly is located on both sides of the accelerator tube placement component and measures the frequency of the accelerator cavity and coupling cavity of the side-coupled cavity under test. The pressure adjustment assembly is located on both sides of the accelerator tube placement component. Using the SSB test bench described in this invention, parameters of the cavity can be tested, and the frequency of the cavity can be adjusted.

Description

Technical Field

[0001] This invention belongs to the field of radio frequency linear accelerator design and manufacturing, specifically relating to a test bench for radio frequency parameters of a side-coupled standing wave accelerator tube. Background Technology

[0002] In the field of radio frequency linear accelerator design and manufacturing, after the accelerating cavity is precision-machined according to the design drawings, due to the influence of machining accuracy and errors, it is usually necessary to perform parameter testing and fine tuning on accelerating structures that do not meet the requirements, so that the radio frequency parameters of each accelerating cavity and the overall accelerating tube meet the requirements. Parameter testing of the accelerating structure mainly includes the frequency and quality factor of each accelerating cavity, the operating frequency of the overall accelerating structure, reflection coefficient, and electric field distribution. Fine tuning mainly includes correcting the frequency of each cavity, matching and tuning the coupler, and tuning the accelerating tube as a whole. The ultimate goal is to make the overall operating frequency, reflection coefficient, and electric field distribution of the accelerating structure meet the requirements.

[0003] For the various tasks involved in the testing and tuning of the acceleration structure, manual testing and tuning methods can be used, or automatic testing and tuning can be carried out using a platform composed of slides. However, these methods are only applicable to cylindrical acceleration tubes.

[0004] Because the coupling cavity and the accelerating cavity are not on the same axis, the acceleration tube is irregular in shape. The existing method is not conducive to accurately testing the parameters of the coupling cavity and the accelerating cavity, resulting in insufficient test accuracy. At the same time, it is not possible to perform overall tuning of the side-coupled standing wave accelerator tube. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a test bench for the radio frequency parameters of a side-coupled standing wave accelerator tube to achieve more accurate parameter testing of the cavity under test, adjustment of the cavity frequency, and optimization of the field distribution inside the accelerator cavity.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A test bench for the radio frequency parameters of a side-coupled standing wave accelerator tube includes an operating table body, an optical panel, a perturbation measurement pulley group, a top pressure adjustment component, an accelerator tube placement component, and a probe test component. The optical panel is disposed on the operating table body, and the accelerator tube placement component is connected to the side of the optical panel away from the operating table body. The perturbation measurement pulley group is located on both sides of the accelerator tube placement component, and nylon wires with perturbation elements are disposed on it to automatically perform non-resonant perturbation measurement on the side-coupled standing wave accelerator tube through the perturbation elements carried by the nylon wires. The probe test component is located on both sides of the accelerator tube placement component to perform frequency measurement on the acceleration cavity and coupling cavity of the side-coupled cavity under test. The top pressure adjustment component is located on both sides of the accelerator tube placement component to perform structural fine-tuning of the cavity under test through top pressure.

[0007] Furthermore, the probe testing assembly includes a combined probe, an angle adjustment assembly, a horizontal slide rail, and a vertical slide rail. There are two horizontal slide rails, each located on opposite sides of the accelerator tube placement component. There are also two vertical slide rails, each located on one of the two horizontal slide rails and movable along the horizontal slide rails in a direction parallel to the horizontal plane. There are also two angle adjustment assemblies and two combined probes, each located on one of the two vertical slide rails and movable along the vertical slide rails in a direction perpendicular to the horizontal plane. The two combined probes are connected to two angle adjustment assemblies 21, so that the angle adjustment assemblies can drive the two combined probes to rotate in a direction parallel to the horizontal plane and / or in a direction perpendicular to the horizontal plane.

[0008] Furthermore, the combined probe includes a hollow tube, a coaxial cable, and a probe head. One end of the hollow tube is connected to the angle adjustment component, the probe head is located on the hollow tube at the end away from the angle adjustment component, and the coaxial cable is located inside the hollow tube and electrically connected to the probe head.

[0009] Furthermore, the hollow tube is provided with an external connection hole that communicates with the interior of the hollow tube, and an outgoing cable is provided in the external connection hole. One end of the outgoing cable is electrically connected to the coaxial cable.

[0010] Furthermore, a magnetic coupling ring is provided on the end of the external connection hole that is away from the end that communicates with the interior of the hollow tube.

[0011] Furthermore, the top pressure distribution assembly includes a top pressure drive component, a top head, a top pressure shaft, a top pressure transmission assembly, and a housing. There are two housings, each located on one side of the acceleration tube placement component. There are two top pressure shafts, each slidably connected to one of the housings. There are two top heads, each connected to one opposite end of one of the top pressure shafts. There are also two top pressure drive components and two top pressure transmission assemblies. The two top pressure drive components are connected to the two top pressure shafts via the two top pressure transmission assemblies, driving the two top pressure shafts to move closer or further apart, so that the top head on the top pressure shaft can apply pressure to the cavity under test.

[0012] Furthermore, the top pressure drive component is a stepper motor.

[0013] Furthermore, the top pressure drive component is a manually adjustable wheel.

[0014] Furthermore, the perturbation measurement pulley group includes an active pulley group and a driven pulley group, and nylon wires with perturbation bodies are wound on the active pulley group and the driven pulley group.

[0015] Furthermore, the active pulley assembly includes an active pulley plate and active pulleys and driven pulleys located at both ends of the active pulley plate. The driven pulley assembly includes a driven pulley plate and driven pulleys located on the driven pulley plate. Nylon threads with micro-perturbations are wound around the active pulleys and the driven pulleys.

[0016] The advantages of this invention are as follows: By measuring the perturbation carried by the nylon wire on the perturbation measurement pulley system, non-resonant perturbation measurement is automatically performed on the side-coupled standing wave accelerator tube to obtain the amplitude distribution of its accelerating field. The combined probe structure design of the probe head and magnetic coupling ring makes it applicable to both dual-probe and single-probe measurement modes of the accelerating cavity. The probe testing assembly measures the radio frequency parameters of the side-coupled standing wave accelerator tube. Based on the measured data, the pressure adjustment components on both sides of the accelerator tube press inward at designated positions of the circular holes in the cavity, causing local deformation, thereby adjusting the radio frequency parameters and field distribution of the side-coupled standing wave accelerator tube. This achieves fine tuning of the accelerating structure of the side-coupled standing wave accelerator tube and accurate measurement of its radio frequency parameters and field distribution. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a test bench for the radio frequency parameters of a side-coupled standing wave accelerator tube according to the present invention;

[0018] Figure 2 yes Figure 1 A schematic diagram of the structure of the probe testing component;

[0019] Figure 3 yes Figure 1 Schematic diagram of the structure of the central active pulley block;

[0020] Figure 4 yes Figure 1 Schematic diagram of the driven pulley block;

[0021] Figure 5 yes Figure 1 Schematic diagram of the structure of the center-top pressure adjustment component;

[0022] Figure 6 yes Figure 2 A schematic diagram of the combined probe structure.

[0023] Explanation of reference numerals in the attached figures:

[0024] 1. Main body of the operating table; 2. Optical panel; 3. Casters; 4. Active pulley group; 5. Driven pulley group; 6. Top pressure adjustment component; 7. Accelerator tube placement component; 8. Fixing frame; 9. Probe testing assembly; 10. Driven pulley; 11. Active pulley; 12. Active pulley upright plate; 13. Driven pulley upright plate; 14. Stepper motor; 15. Top head; 16. Top pressure shaft; 18. Housing; 19. Manual adjustment wheel; 20. Combined probe; 21. Angle adjustment assembly; 22. Horizontal slide rail; 23. Longitudinal slide rail; 24. Hollow tube; 25. Probe head; 26. Coaxial cable; 27. Lead-out cable; 28. Magnetic coupling ring. Detailed Implementation

[0025] The present invention will now be further described with reference to the accompanying drawings and specific embodiments.

[0026] like Figure 1-6 As shown, the present invention provides a test bench for the radio frequency parameters of a side-coupled standing wave accelerator tube (SCWT), comprising an operating platform body 1, an optical panel 2, a perturbation measurement pulley group, a top pressure adjustment assembly 6, an accelerator tube placement component 7, and a probe test assembly 9. The optical panel 2 is mounted on the operating platform body 1, and the accelerator tube placement component 7 is connected to the side of the optical panel 2 away from the operating platform body 1. The perturbation measurement pulley group is located on both sides of the accelerator tube placement component 7, and nylon wires with perturbation elements are mounted on it to automatically perform non-resonant perturbation measurements on the side-coupled SCWT accelerator tube through the perturbation elements on the nylon wires, thereby obtaining the amplitude distribution of its acceleration field. The probe test assembly 9 is located on both sides of the accelerator tube placement component 7 to measure the frequency of the acceleration cavity and coupling cavity of the side-coupled cavity under test. The top pressure adjustment assembly 6 is located on both sides of the accelerator tube placement component 7 to fine-tune the structure of the cavity under test by applying top pressure, thereby changing the cavity's frequency, Q value, and field distribution.

[0027] It is understandable that after the probe testing component 9, nylon wire and micro-perturbation body effectively measure the frequency and field distribution of the cavity under test, the top pressure adjustment component 6 applies pressure to the structure of the cavity under test, causing local deformation of the cavity, thereby achieving the tuning of the cavity frequency and field distribution through edge coupling acceleration.

[0028] Furthermore, the probe testing assembly 9 includes a combined probe 20, an angle adjustment assembly 21, a horizontal slide rail 22, and a longitudinal slide rail 23. There are two horizontal slide rails 22, located on opposite sides of the accelerator tube placement component 7. There are also two longitudinal slide rails 23, each located on one of the two horizontal slide rails 22 and movable along the horizontal slide rails 22 in a direction parallel to the horizontal plane. There are also two angle adjustment assemblies 21 and two combined probes 20. The two angle adjustment assemblies 21 are located on the two longitudinal slide rails 23 and can move along the longitudinal slide rails 23 in a direction perpendicular to the horizontal plane. The two combined probes 20 are connected to the two angle adjustment assemblies 21, so that the angle adjustment assemblies 21 can rotate the two combined probes 20 in a direction parallel to the horizontal plane and / or in a direction perpendicular to the horizontal plane, thereby adjusting the measurement position of the combined probes 20.

[0029] It is understood that the horizontal slide rail 22 and the vertical slide rail 23 can be XY axis lead screw module structures or any other structure, as long as the horizontal slide rail 22 and the vertical slide rail 23 can cooperate with each other to drive the angle adjustment component 21 located on the vertical guide rail 23 to move in the direction parallel to the horizontal plane and perpendicular to the horizontal plane, thereby driving the combined probe 20 to move together.

[0030] It is understood that the angle adjustment component 21 can be a combination structure of a worm gear, a gear combination transmission structure, or any other structure, as long as it can drive the combined probe 20 to rotate in a direction perpendicular to and / or parallel to the horizontal plane. The rotation can be driven by a motor or manually. For example, the angle adjustment component 21 includes a fixed block, a connecting block, and a base. The combined probe 20 is located on the fixed block, which slides against the connecting block, and the contact surfaces of the fixed block and the connecting block are mutually adapted arc surfaces, allowing the fixed block to rotate in a direction perpendicular to the horizontal plane by sliding. The side of the connecting block away from the fixed block is rotatably connected to the base, which is connected to the longitudinal slide rail 23. The combined probe 20 rotates in a direction perpendicular to and / or parallel to the horizontal plane by the sliding of the fixed block relative to the connecting block in a direction perpendicular to the horizontal plane and the rotation of the connecting block relative to the base in a direction parallel to the horizontal plane. The driving method of the fixed block sliding relative to the connecting hole and the driving method of the connecting block rotating relative to the base can be driven by a gear set via a motor or manually.

[0031] Furthermore, the combined probe 20 includes a hollow tube 24, a coaxial cable 26, and a probe head 25. One end of the hollow tube 24 is connected to the angle adjustment component 21, and the probe head 25 is located on the end of the hollow tube 24 away from the angle adjustment component 21. The coaxial cable 26 is located inside the hollow tube 24 and is electrically connected to the probe head 25 to transmit the detection results of the probe head.

[0032] Furthermore, the hollow tube 24 is provided with an external connection hole that communicates with the interior of the hollow tube 24, and an outgoing cable 27 is provided in the external connection hole. One end of the outgoing cable 27 is electrically connected to the coaxial cable 26.

[0033] It is understood that the external connection hole is a through hole, through which the cable 27 is inserted into the hollow tube 24 to be electrically connected to the coaxial cable 26.

[0034] Furthermore, a magnetic coupling ring 28 is provided on the end of the external connection hole that is away from the end that communicates with the interior of the hollow tube 24.

[0035] It is understandable that an electrical connection with an external cable 27 can be achieved through the magnetic coupling ring 28.

[0036] It's understandable that the hollow tube 24 is made of stainless steel.

[0037] Furthermore, the top pressure distribution assembly 6 is fixed to both sides of the acceleration tube placement component 7 by the fixing bracket 8.

[0038] It is understandable that the position of the top pressure distribution component 6 on both sides of the acceleration placement component 7 can be adjusted by the fixing frame 8 to adapt to the top pressure at any position of the cavity to be tested.

[0039] Furthermore, the top pressure adjustment assembly 6 includes a top pressure drive component, a top head 15, a top pressure shaft 16, a top pressure transmission assembly (not shown in the figure), and a housing 18. There are two housings 18, located on opposite sides of the accelerating tube placement component 7. There are two top pressure shafts 16, each slidably connected to one of the two housings 18. There are two top heads 15, each connected to one opposite end of one of the two top pressure shafts 16. There are also two top pressure drive components and two top pressure transmission assemblies. The two top pressure drive components are connected to the two top pressure shafts 16 via the two top pressure transmission assemblies, driving the two top pressure shafts 16 to move closer or further apart. This allows the top heads 15 on the top pressure shafts 16 to apply pressure to the cavity under test, achieving fine-tuning of the cavity's structure, i.e., tuning the frequency and field distribution of the side-coupled accelerating cavity.

[0040] Furthermore, the top pressure drive component is a stepper motor 14.

[0041] Furthermore, the top pressure drive component is a manually adjustable wheel 19.

[0042] It is understandable that the top pressure transmission assembly can be any transmission structure such as a gear set or a worm gear, as long as the top pressure drive component can drive the top pressure shaft 16 to move in a direction that is closer to or further away from each other through the top pressure transmission assembly, so as to achieve top pressure on the cavity to be tested.

[0043] It is understood that the top pressure shaft 16 and the housing 18 can be slidably connected through shaft hole fitting or other arbitrary means.

[0044] Furthermore, the perturbation measurement pulley system includes an active pulley system 4 and a driven pulley system 5, with nylon wires containing perturbations wound around the active pulley system 4 and the driven pulley system 5.

[0045] Furthermore, the active pulley assembly 4 includes an active pulley plate 12 and active pulleys 11 and driven pulleys 10 located at both ends of the active pulley plate 12. The driven pulley assembly 5 includes a driven pulley plate 13 and driven pulleys 10 located on the driven pulley plate 13. The active pulleys and driven pulleys are wound with nylon lines containing micro-perturbations.

[0046] Furthermore, the accelerator tube placement component 7 is provided with a V-shaped groove to place the accelerator tube to be tested in the V-shaped groove for fixation.

[0047] Furthermore, screw holes are evenly arranged on the optical panel 2 to facilitate the installation and fixation of various components on its surface.

[0048] Furthermore, the bottom of the main body 1 of the control panel is equipped with outward-facing wheels 3.

[0049] The working principle of this invention is as follows: An active pulley 11 is connected to a pulley stepper motor, and a control system controls the motor's movement. The motor's speed is adjustable from 0.5 mm / s to 50 mm / s, and the movement distance can be arbitrarily set. A nylon wire with a micro-perturbation is passed through an acceleration tube and tightened by four pulleys. By controlling the active pulley 11, the micro-perturbation moves within the acceleration tube. The micro-perturbation causes small reflections within the acceleration tube. By measuring the change in the reflection coefficient caused by the micro-perturbation at different positions on the axis, the change in the field distribution can be determined.

[0050] The combined probe 20 is inserted into the beam aperture of the accelerating cavity, with the side of the combined probe 20 with the magnetic coupling ring 28 facing the direction of the side-coupled cavity under test. When testing the accelerating cavity, a short-circuit bar can be inserted into the side-coupled cavity to detune it, leaving only the accelerating cavity between the two combined probes 20, thus completing the acceleration cavity test. When testing the side-coupled cavity, the outer shell of the combined probe 20 will short-circuit and detune the adjacent accelerating cavities on both sides of the side-coupled cavity under test, thus completing the coupling cavity test.

[0051] The top pressure adjustment component 6 has two working modes: manual and automatic. In manual mode, the manual speed is set, and the top pressure action can be initiated by clicking the button on the operation interface. In automatic mode, the movement speed and movement distance need to be set, and then the top pressure is initiated through the operation interface, causing local deformation of the cavity, thereby completing the tuning of the frequency of the side-coupled acceleration cavity.

[0052] As can be seen from the above embodiments, this invention automatically performs non-resonant perturbation measurement on the side-coupled standing wave accelerator tube by measuring the perturbation of the nylon wire on the perturbation measurement pulley system, thereby obtaining the amplitude distribution of its accelerating field. The combined probe structure design of the probe head and magnetic coupling ring makes it applicable to both dual-probe and single-probe measurement modes of the accelerating cavity. The probe test assembly measures the radio frequency parameters of the side-coupled standing wave accelerator tube, and based on the measured data, the pressure adjustment components on both sides of the accelerator tube press inward at the circular holes at designated positions in the cavity, causing local deformation, thereby adjusting the radio frequency parameters and field distribution of the side-coupled standing wave accelerator tube, completing the fine tuning of the accelerating structure of the side-coupled standing wave accelerator tube and the accurate measurement of radio frequency parameters and field distribution.

[0053] The device described in this invention is not limited to the embodiments described in the specific implementation. Other implementation methods derived by those skilled in the art based on the technical solution of this invention also fall within the scope of technical innovation of this invention.

Claims

1. A test bench for the radio frequency parameters of a side-coupled standing wave accelerator tube, characterized in that, include: The system comprises an operating platform body, an optical panel, a perturbation measurement pulley assembly, a top pressure adjustment component, an accelerator tube placement component, and a probe testing component. The optical panel is mounted on the operating platform body, and the accelerator tube placement component is connected to the side of the optical panel away from the operating platform body. The perturbation measurement pulley assembly is located on both sides of the accelerator tube placement component, and nylon wires with perturbation elements are mounted on them to automatically perform non-resonant perturbation measurements on the side-coupled standing wave accelerator tube using the perturbation elements carried by the nylon wires. The probe testing component is located on both sides of the accelerator tube placement component to measure the frequency of the accelerating cavity and coupling cavity of the side-coupled cavity under test. The top pressure adjustment component is located on both sides of the accelerator tube placement component to perform structural fine-tuning of the cavity under test through top pressure. The probe testing component includes a combination of... The device comprises a probe, an angle adjustment assembly, a horizontal slide rail, and a vertical slide rail. There are two horizontal slide rails, each located on opposite sides of the accelerator tube placement component. There are also two vertical slide rails, each situated on one of the two horizontal slide rails and movable along the horizontal slide rails in a direction parallel to the horizontal plane. Two angle adjustment assemblies are also present, each situated on one of the two vertical slide rails and movable along the vertical slide rails in a direction perpendicular to the horizontal plane. The two combined probes are connected to the two angle adjustment assemblies, allowing the angle adjustment assemblies to drive the two combined probes to rotate in a direction parallel to the horizontal plane and / or perpendicular to the horizontal plane.

2. The test bench for RF parameters of a side-coupled standing wave accelerator tube as described in claim 1, characterized in that: The combined probe includes a hollow tube, a coaxial cable, and a probe head. One end of the hollow tube is connected to the angle adjustment component, and the probe head is located on the end of the hollow tube away from the angle adjustment component. The coaxial cable is located inside the hollow tube and is electrically connected to the probe head.

3. The test bench for RF parameters of a side-coupled standing wave accelerator tube as described in claim 2, characterized in that: The hollow tube is provided with an external connection hole that communicates with the interior of the hollow tube. A lead-out cable is provided in the external connection hole, and one end of the lead-out cable is electrically connected to the coaxial cable.

4. The test bench for RF parameters of a side-coupled standing wave accelerator tube as described in claim 3, characterized in that: A magnetic coupling ring is provided on the end of the external connection hole that is away from the end that communicates with the interior of the hollow tube.

5. The test bench for RF parameters of a side-coupled standing wave accelerator tube as described in claim 1, characterized in that: The pressure distribution assembly includes a pressure drive, a pressure head, a pressure shaft, a pressure transmission assembly, and a housing. There are two housings, each located on one side of the acceleration tube placement assembly. There are two pressure shafts, each slidably connected to one of the housings. There are two pressure heads, each connected to one opposite end of one of the pressure shafts. There are also two pressure drive components and two pressure transmission assemblies. The two pressure drive components are connected to the two pressure shafts via the two pressure transmission assemblies, driving the two pressure shafts to move closer or further apart, so that the pressure head on the pressure shaft can apply pressure to the cavity under test.

6. The test bench for RF parameters of a side-coupled standing wave accelerator tube as described in claim 5, characterized in that: The top pressure drive component is a stepper motor.

7. The test bench for RF parameters of a side-coupled standing wave accelerator tube as described in claim 5, characterized in that: The top pressure drive component is a manually adjustable wheel.

8. The test bench for RF parameters of a side-coupled standing wave accelerator tube as described in claim 1, characterized in that: The perturbation measurement pulley group includes an active pulley group and a driven pulley group, and nylon wires with perturbation bodies are wound on the active pulley group and the driven pulley group.

9. The test bench for RF parameters of a side-coupled standing wave accelerator tube as described in claim 8, characterized in that: The active pulley assembly includes an active pulley plate and active and driven pulleys located at both ends of the active pulley plate. The driven pulley assembly includes a driven pulley plate and driven pulleys located on the driven pulley plate. Nylon threads with micro-perturbations are wound around the active pulleys and the driven pulleys.

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