US 12,345,277 B2
Rotor assembly for a turbomolecular pump
Richard Glyn Horler, Burgess Hill (GB); Ales Kubis, Lutin (CZ); and David Student, Lutin (CZ)
Assigned to Edwards S.R.O., Olomouc (CZ)
Appl. No. 18/254,066
Filed by Edwards S.R.O., Lutin (CZ)
PCT Filed Nov. 23, 2021, PCT No. PCT/EP2021/082602
§ 371(c)(1), (2) Date May 23, 2023,
PCT Pub. No. WO2022/112212, PCT Pub. Date Jun. 2, 2022.
Claims priority of application No. 2018530 (GB), filed on Nov. 25, 2020.
Prior Publication US 2024/0093701 A1, Mar. 21, 2024
Int. Cl. F04D 29/66 (2006.01); F04D 19/04 (2006.01); F04D 29/058 (2006.01); F04D 29/32 (2006.01); F04D 29/64 (2006.01)
CPC F04D 29/662 (2013.01) [F04D 19/042 (2013.01); F04D 19/048 (2013.01); F04D 29/058 (2013.01); F04D 29/321 (2013.01); F04D 29/644 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A rotor assembly for a turbomolecular pump, the rotor assembly comprising:
a rotor shaft extending along a longitudinal axis about which the rotor assembly is configured to rotate, the rotor shaft defining a circumferentially-extending inner shaft surface;
at least one magnet mounted to the rotor shaft for rotation therewith;
a plurality of rotor blades extending from the rotor shaft; and
a balancing member defining a circumferentially-extending outer surface fitted within the rotor shaft such that the circumferentially-extending outer surface of the balancing member contacts the circumferentially-extending inner shaft surface to provide an interference fit between the balancing member and the rotor shaft such that the balancing member is retained in compression by the rotor shaft and the balancing member is positioned to axially retain the at least one magnet to the rotor shaft;
wherein the balancing member comprises a plurality of balancing features in the form of a plurality of holes defined therein for receiving balance weights.