| 摘要 |
PROBLEM TO BE SOLVED: To provide a vacuum pump capable of preventing a vacuum chamber from being broken by breaking torque generated when a rotating rotor collides with an inner wall of a casing. SOLUTION: The diameter of a bolt hole 3 of a connection flange part 1a with the vacuum chamber, and a diameter of a bolt hole of a connecting part of a pump case and a lower base are respectively determined to be larger than a diameter of each bolt to be inserted therein by 20% or more, whereby the vacuum chamber and the pump case or the pump case and the base are respectively slid by a clearance between the vacuum chamber connection hole and the pump chamber connection bolt 30, and a clearance between the bolt hole for connecting the pump case and the base, and the bolt for connecting the pump case and the pump, when the vacuum pump 10 is rotated by the breaking torque as a whole, whereby the breaking torque is absorbed, and the transmission of the breaking torque to the vacuum chamber 200 can be prevented. COPYRIGHT: (C)2003,JPO |
