| 摘要 |
PROBLEM TO BE SOLVED: To provide a vacuum pump capable of excellently maintaining exhaust efficiency by reducing influence on a gap between members even if each member is unevenly and thermally expanded by a partial temperature rise generated during the operation of the pump.SOLUTION: A cylinder 10 of a vacuum pump 100 stores a body 3 of a rotor 30 so that an intake chamber 21 and an exhaust chamber 22 are sectioned and an axial direction gap G1 is formed between an opposed surface 110 opposed to a first end face 31 directing in the direction of a rotor shaft 33 and the first end face 31. The cylinder 10 is formed so that a gap d1 formed in the intake chamber 21 of the axial direction gap G1 becomes larger than a gap d2 formed in the exhaust chamber 22. The exhaust chamber 22 side is thermally expanded to have larger elongation amount than the intake chamber 21 side in the cylinder 10 according to a temperature rise during the operation of the vacuum pump 100. However, the axial direction gap G1 is set to d1>d2 in advance, thereby preventing the sizes of the axial direction gap G1 formed in the intake chamber 21 and the exhaust chamber 22 from being made uneven. |
