摘要 |
The present invention provides a vacuum pump (1) which reduces a damaging torque produced when a rotor (2) rotating at high-speed crashes into a screw stator (7) or the like. The vacuum pump has a rigid ring (9) disposed around the screw stator such that a shock load from the screw stator causes the rigid ring to rotate. When a brittle facture occurs in the rotor rotating at high-speed, for example, and a part of the rotor crashes into the screw stator, a rotating torque, i.e., a damaging torque causing the entire vacuum pump to rotate is likely to occur. However, this damaging torque is absorbed by the rotation of the rigid ring and eventually subsides. <IMAGE> |