| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a particle accelerator which can enhance its reliability by preventing entry of air into a vacuum vessel while maintaining lubricity of the sliding surface of a shaft member. <P>SOLUTION: The particle accelerator is configured to have a shaft seal device 30 which supplies a lubricant onto the peripheral surface 21a of a retractable shaft member 21 penetrating the wall 3a of a vacuum vessel to reach the vacuum environment in the vessel, and evacuates a vacancy 38A formed above the peripheral surface 21a of the shaft member 21. Thus, entry of air into the vacuum vessel can be prevented by evacuating the vacancy 38A formed above the peripheral surface 21a of the shaft member 21 while maintaining lubricity of the shaft member by the supplied lubricant . <P>COPYRIGHT: (C)2013,JPO&INPIT |
