(57) In order to improve the exhaust performance of the turbomolecular pump comprising
an exhaust stage, intermediate stage, and compression stage formed in sequence by
rotor blades and the stator blades to effect exhaust and compression of gas, and rotor
blades 141 to 144 are installed to a rotor shaft 12 supported by a bearing 20, and
fixed stator blades 181 to 184 are arranged between the rotor blades, each vane of
the rotor blade 144 forming the compression stage is arranged radially in a tilted
manner with respect to the rotor shaft 12, and curved in the width direction so as
to be convex to the rear side with respect to the vane rotation direction. Therefore,
gas flows along the plate surface at the periphery of each vane 144b, so that the
gas can be moved from the upper side to the lower side, thereby avoiding turbulence.
|
|
