Rotary Blood Pump

A fluid pump comprising:

• a pump housing;
• a rotor rotatably disposed in said pump housing;
• a plurality of ramps located between said pump housing and said rotor;
• a flat surface associated with each of said plurality of ramps;
• each of said flat surfaces extending horizontally relative to said angle of its associated ramp;
• a passive axial magnetic bearing supporting said rotor and creating a biasing force on the rotor in an axial direction;
• said plurality of ramps and said passive axial magnetic bearing sized to cooperate with each other so as to suspend said impeller during operation of said pump.

A method of pumping blood comprising:

• providing a pump housing defining a pump chamber having an inlet and an outlet and a rotor rotatably disposed in said pump chamber;
• spinning said rotor
• generating a hydrodynamic bearing between said pump housing and said rotor using a plurality of a plurality of lifts positioned between said pump housing and said rotor;
• supporting said rotor with a passive axial magnetic bearing
• said hydrodynamic bearing and said passive axial magnetic bearing cooperating with each other so as to enhance axial stability to said rotor during rotation of said rotor.