In a turbo-molecular pump with a high vacuum-side induction area and of a
rotational symmetrical arrangement, comprising a compressor turbine
including a rotor and a stator tube having axially alternately tightly
arranged rotor blade rings and stator vane rings with oppositely oriented
blade and vane surfaces, a pre-vacuum chamber with a gas guide structure
for the connection of a pre-pumping system, a drive module and a bearing
unit, the turbo-molecular pump has a center area with a central coaxial
open space extending from an ambient end to the high vacuum-side
induction area and the open space is closed at its end adjacent the
ambient end thereof by a flange in a vacuum-tight manner or is connected
to a vacuum recipient, and the high-vacuum end of this space is separated
from a pre-vacuum space.