Patent ID: 8087907
Filing Date: 2012-01-03
Classification: F04D,F16C

Abstract:
1. A turbo vacuum pump comprising: a casing; a pumping section having rotor blades and stator blades which are disposed alternately in said casing; a main shaft for supporting said rotor blades; and a bearing and motor section having a motor for rotating said main shaft and a bearing mechanism for supporting said main shaft rotatably; wherein a gas bearing is used as a bearing for supporting said main shaft in a thrust direction, spiral grooves are formed in both surfaces of a stationary part of said gas bearing, and said stationary part having said spiral grooves is placed between an upper rotating part and a lower rotating part which are fixed to said main shaft; and wherein a thrust magnetic bearing for canceling out a thrust force generated by the differential pressure between a discharge side and an intake side by an evacuation action of said pumping suction is provided, and a displacement sensor for measuring an axial displacement of a rotor having said main shaft is provided.