| 摘要 |
A vacuum pump includes a casing having an inlet port and an outlet port, a stator portion provided inside the casing and a rotor portion having a shaft rotatably supported inside the casing and a rotor disposed on the shaft and provided with a gas transfer mechanism that transfers a gas from the inlet port to the outlet port. The rotor portion is arranged with a predetermined clearance between the rotor portion and the stator portion. A motor rotates the shaft. Vibration detection disposed in the stator portion detects vibrations by converting vibration amplitude to an electric signal. Contact detection judges an occurrence of contact between the stator portion and the rotor portion when, in the vibration detected by the vibration detection, an amplitude in frequency of a specific vibration caused by contact between the stator portion and the rotor portion exceeds a predetermined threshold value. |
