Patent ID: 7541807
Filing Date: 2009-06-02
Classification: G01R

Abstract:
1. A rotor drive apparatus for spinning of an NMR sample comprising: a rotor including a rotor body disposed along an axis of rotation and a rotor end member disposed at an axial end of the rotor body, the rotor end member comprising a rotor end surface and a plurality of drive vanes formed in the rotor end surface, the rotor end surface including a tapered rotor surface terminating at a rotor tip disposed at the axis of rotation; and a stator including a stator body and a tapered stator surface, the tapered stator surface axially spaced from the tapered rotor surface to form a bearing gap having a tapered profile coaxial with the axis of rotation, the stator further comprising a gas passage formed through the stator body and terminating at an axial gas injection orifice, the axial gas injection orifice disposed at the tapered stator surface and coaxial with the axis of rotation, wherein the rotor end member and the stator cooperatively form a gas path directed from the axial gas injection orifice and radially outward through the bearing gap at an angle to the axis of rotation.