A Disposable Magnetic Bearing System for an Extracorporeal Centrifugal Blood Pump

In order to increase the design flexibility of the rotor/impeller in an extracorporeal maglev centrifugal blood pump and realize a magnet-less disposable pump head, a novel combination of a radial magnetic bearing and a magnetic coupling disk for transmitting the rotational torque from the motor, which surrounds the disposable magnet-less rotor/impeller, is proposed. The magnetic bearing system actively controls the radial motion of the rotor/impeller and passively controls motion in the other directions. Contactless stable levitation and rotation of the rotor at speeds from 0 to 3,200rpm were realized with a bearing system fabricated for a 50mm diameter rotor.