Abstract: The invention relates to means and methods by which a rotor is rotationally journalled relative to a stator in a magnetic field provided concentrically about a longitudinal axis, coincident with the rotor and the stator axis such that an annular gap is formed between the rotor and the stator. A flexible, sheet metal foil of non-magnetic and electrically conductive material is arranged for insertion in the annular gap in relative rotation to the rotor. The foil is shaped for generating a fluid film in cooperation with the revolving periphery of the rotor, and effective to counteract oscillating rotation of said rotor due to the formation of eddy currents that are induced in the sheet metal foil upon displacement within the magnetic field.

Abstract: Device for magnetic suspension of a rotor (10, 20, 30) in relative rotational movement along a predetermined rotation symmetric path with respect to a stator (14, 24, 26, 34, 36). Rotor (10, 20, 30) comprises a rotational body (11, 21, 31) which essentially consists of an electrically conductive unmagnetic material. Fitted at the stator (14, 24, 26, 34, 36) is at least one magnetic member (12, 22, 25, 32, 35), which comprises at least one rotation symmetric magnet (12, 22, 25, 32, 35) concentric with the rotational axis. The magnetic member is disposed to give rise to a rotation symmetric magnetic field concentric with the rotational axis. When and only when the rotational body (11, 21, 31) tends to leave the predetermined path and rotate eccentric, the magnetic field generates induced eddy currents in the rotational body (11, 21, 31), the eddy currents gives rise to restoring stabilising forces.

Abstract: High velocity vacuum pump, such as turbomolecular pump, drag pump, centrifugal pump or the like, comprising a stator (10) and a rotor (18,43,53), which is axially and radially suspended with respect to the stator (10) by magnetic bearings (27). The vacuum pump may comprise two at the same rotor provided, parallelly acting pump portions, each one comprising two pumping steps. The rotor may be cylindrical and rotates around an inner stator shaft and within an outer stator portion. In that way, one pumping step (22) is formed between the inner stator shaft and the rotor and another pumping step (24) between the outer stator portion (10) and the rotor. The magnet bearing comprises at least one rotation symmetric magnet (27) and is disposed to give rise to a rotation symmetric magnetic field which is centered around the rotational axis.