| 摘要 |
A turbomolecular pump including a casing stationary blades arranged in a plurality of stages in the casing axially thereof, rotating blades arranged between the stationary blades and located on an outer periphery of a rotor located in a central portion of the casing, and a bearing device journaling the rotor at its high vacuum and end a low vacuum end. A first permanent magnet of the fixed side having a high Curie point and a second permanent magnet of the rotor side located in juxtaposed relation to the first permanent magnet constitute a magnetic bearing of an attraction type for journaling the rotor at its high vacuum end. A pivot type hydrodynamic bearing or active magnetic bearings journal the rotor at its low vacuum end. |
