Magnetic bearing type vacuum pump

摘要

To provide a magnetic bearing type vacuum pump, which can suppress the generation of eddy current on a shaft to be small in heat generation on the shaft and to be excellent in efficiency. In a shaft, an electromagnet target composing a target for electromagnets composing a radial magnetic bearing portion, a radial sensor target composing a target for a coil detecting a displacement of the shaft in the vicinity of the magnetic bearing portion and a collar between the electromagnet target and the radial sensor target are composed of laminated steel plates, so that the generation of eddy current caused on the shaft due to magnetic field generated in the magnetic bearing portion is reduced.