| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a turbo vacuum pump improving exhaust performance by reducing a gap between a rotary blade and a stationary blade, accurately estimating temperature and thermal expansion quantity of a rotary shaft, and issuing warning or stopping operation before the rotary blade and the stationary blade touch. <P>SOLUTION: The turbo vacuum pump is provided with: at least a pair of axial magnetic bearings 59 magnetically floating a rotary shaft 54; a rotary blade 52 attached on a rotary shaft; a stationary blade 53 disposed to oppose to the rotary blade; and a motor 55 rotationally driving the rotary shaft. An exhaust part 90 is constructed by disposing the rotary blade and the stationary blade near one end part of the rotary shaft, a motion control part 91 is constructed by disposing an axial magnetic bearing 58 and a first axial displacement sensor 59 detecting an axial position of the rotary shaft near another end of the rotary shaft, and a second axial displacement sensor 60 detecting axial direction of the rotary shaft is disposed near the exhaust part. <P>COPYRIGHT: (C)2009,JPO&INPIT |
