Patent ID: 8684902

Claim:
A pump apparatus comprising: a centrifugal pump housing defining a pumping chamber for pumping a liquid, the centrifugal pump housing having a spindle extending into the pumping chamber; and a spindle magnet assembly comprising a first and a second magnet disposed within the spindle, wherein the first and second magnets are arranged proximate each other with their respective magnetic vectors being parallel to an axis of rotation of a rotor of said pump; a rotor with a rotor magnet assembly comprising a third and a fourth magnet disposed within a non-bladed portion of the rotor, wherein the third and fourth magnets are arranged proximate each other with their respective magnetic vectors being parallel to said axis of rotation of said rotor, wherein said spindle and rotor magnet assemblies form a passive magnetic axial bearing wherein a relative orientation of the spindle and rotor magnet assemblies are selected so that the spindle and rotor magnet assemblies attract each other; and, a hydrodynamic bearing formed of a plurality of contoured surfaces between said housing and said rotor.