Patent ID: 6736593
Filing Date: 2004-05-18
Classification: F04D,F16C

Abstract:
A protective device for protecting a turbo molecular pump having a rotor mounted for undergoing rotation, an intake port for sucking gas by rotation of the rotor, and an exhaust port for exhausting the gas sucked from the intake port, the protective device comprising:detecting means for detecting the occurrence of an abnormal phenomenon in the turbo molecular pump; abnormal phenomenon inference means for inferring a type of the abnormal phenomenon detected by the detecting means; value obtaining means for inferring a magnitude of damage given to the turbo molecular pump by the abnormal phenomenon inferred by the abnormal phenomenon inference means and for obtaining a value weighted based on the inferred magnitude of the damage; value accumulation means for accumulating the value obtained by the value obtaining means; sum obtaining means for obtaining a sum of the values accumulated in the value accumulation means; and protecting means for protecting the turbo molecular pump in a case where the sum obtained by the sum obtaining means exceeds a predetermined value.