Radio frequency linear accelerator control system

• US 4,992,744 A
• Filed: 05/30/1989
• Issued: 02/12/1991
• Est. Priority Date: 05/30/1988
• Status: Expired due to Fees

• Current Assignee: Shimadzu Corporation
• Original Assignee: Shimadzu Corporation
• Inventors: Hirakimoto, Akira, Fujita, Hiroyuki
• Primary Examiner(s): Yusko, Donald J.
• Assistant Examiner(s): Horabik, Michael
• Application Number:
  US07/358,827
• Time in Patent Office: 623 Days
• Field of Search: 328/233, 313/359.1, 315/111.61, 315/5.42, 331/3, 331/94.1
• US Class Current: 315/505
• CPC Class Codes: H05H 7/02 Circuits or systems for supplying or feeding radio-frequency energy radio-frequency generators H03B
• CPC Class Codes: H05H 7/18 Cavities; Resonators travelling-wave tubes H01J23/18; hyperfrequency cavities in general H01P7/04, H01P7/06
• CPC Class Codes: H05H 9/00 Linear accelerators

Abstract

A control system for controlling a radio frequency resonant cavity type linear accelerator so as to be power-supplied always at a resonance frequency of a resonat cavity constituting the accelerator. The system consists essentially of a signal pick-up coil inserted in the resonat cavity, a voltage-controlled oscillator assembly, a phase detector for detecting a phase difference between a signal picked up from the cavity by the signal pick-up coil and an output from the voltage-controlled oscillator assembly. An output from the phase detector controls the voltage-controlled oscillator assembly so as to make it oscillate at a frequency equal to a resonance frequency of the resonant cavity.

Claims

1. A radio frequency linear accelerator control system for controlling the frequency of a radio frequency power to a resonant cavity type radio frequency linear accelerator, said system comprising:

a loop coupler for taking out a signal from said resonant cavity type radio frequency linear accelerator;

a voltage-controlled oscillator for feeding a radio frequency power to said resonant cavity type radio frequency linear accelerator; and

a phase detector for outputting a frequency control signal according to a relative phase difference between a signal picked up by said loop coupler and a signal made to branch from said radio frequency power being fed to said resonant cavity type radio frequency linear accelerator, said frequency control signal being fed back to said voltage-controlled oscillator for maintaining a frequency of said radio frequency power at a predetermined value.

2. A control system for controlling the frequency of a radio frequency power to a resonant cavity type radio frequency linear accelerator to maintain the frequency of the radio frequency power at a resonant frequency characteristic of a geometry of the accelerator, said control system comprising:

a loop coupler for taking out a signal form said resonant cavity type radio frequency linear accelerator;

a radio frequency power amplifier whose output is supplied to said resonant cavity type radio frequency linear accelerator;

a voltage-controlled oscillator for exciting said radio frequency power amplifier; and

a phase detector for outputting a frequency control voltage in accordance with a relative phase difference between a signal picked up by said loop coupler and a signal made to branch from said radio frequency power amplifier, said frequency control voltage being fed back to said voltage controlled oscillator for maintaining said frequency at a predetermined value;

whereby said resonant cavity type radio frequency linear accelerator is always supplied at a frequency equal to a resonant frequency thereof.