Rotodynamic pump with spherical motor

摘要

A pump-motor unit of the type having an impeller connected to an armature and where the armature is separated from a stator by an air gap. The armature comprises a magnetic material having sufficient residual flux density whereby when the torque load on the impeller-armature structure is low, the magnet will act as a permanent magnet to provide synchronous rotation of the armature with respect to magnetic flux generated by the stator and when the torque load on the impeller-armature structure is high, will allow magnetic reversal whereby the armature will rotate asynchronously with respect to the magnetic flux generated by the stator.