TURBOMOLECULAR VACUUM PUMP Russian patent published in 1994 - IPC

FIELD: manufacture of pumps. SUBSTANCE: gas-dynamic seal is formed by surface of cylindrical stator coated with fluoroplastic with many cylindrical grooves forming the sealing zone and multistart spiral grooves made on surface of rotor facing the cylindrical stator; depth of these grooves reduces towards discharge side; direction of these grooves is opposite to sense of rotation of rotor. Second stage is made in form of vortex stage which has stator and rotor disks. Stator disks are flat and are coated with fluoroplastic seal with concentric grooves forming the labyrinth seal. Rotor disks have blades over contour inclined towards side of rotation. On the surfaces of the disks there are passages inclined to side opposite to rotation of disk on side of gas inlet and to side of rotation on side of gas outlet. EFFECT: enhanced efficiency. 3 dwg