Motor for a shaftless spinning rotor for an open-end spinning machine

Claim 1

A shaftless rotor assembly for an open-end spinning machine comprising an axial field motor including a rotor and a stator, the rotor having a body defining a spinning chamber, an opening into the chamber and a bearing face opposite the rotor opening, and the stator having an opposed facing bearing face, means for producing a combined magnetic and gas bearing for supporting the rotor relative to the stator including means for producing a first field of magnetic flux for orienting and maintaining a rotational axis of the rotor in a stationary disposition, means for producing a second field of magnetic flux for driving rotation of the rotor about the axis, and means for conducting the magnetic flux for the guiding and driving magnetic fields, wherein the means for producing the guiding magnetic field comprises magnets concentrically arranged about the rotor axis including a first dynamically balanced magnet unit projecting from one of the two bearing faces and a second corresponding dynamically balanced magnet unit recessed in the opposed bearing face, the dynamically balanced magnet units being dimensioned to define axial and radial air gaps therebetween.