Two-stage rotodynamic blood pump

A pump comprising:

• a housing;
• at least one impeller;
• and
• a motor for imparting rotation to the at least one impeller, the motor comprising:
• a stator supported in the housing;
• a rotor assembly comprising a rotor supported in the housing for rotation relative to the stator about an axis;
• wherein the stator comprises a stator core comprising first and second laminations spaced from each other along the length of the stator core, and motor windings wound around the first and second laminations;
• and wherein the rotor comprises a rotor core;
• a first magnet assembly that extends around an axial portion of the rotor core and a second magnet assembly that extends around a second axial portion of the rotor core, the first and second magnet assemblies being spaced from each other along the length of the rotor, wherein the first lamination and first magnet assembly act as a first driver for the motor, and the second lamination and second magnet assembly act as a second driver for the motor, the pump also comprising:
• a first impeller operatively coupled to a first axial end of the rotor for rotation with the rotor about the axis;
• and
• a second impeller operatively coupled to a second axial end of the rotor, opposite the first axial end, for rotation with the rotor about the axis;
• wherein the rotor assembly is movable along the axis relative to the housing to adjust hydraulic performance characteristics of the pump, the pump further comprising:
• a first pumping stage comprising a first pump housing part that helps define a first pumping chamber in which the first impeller is supported for rotation about the axis, the first impeller being movable along the axis relative to the first pump housing part;
• and
• a second pumping stage comprising a second pump housing part that helps define a second pumping chamber in which the second impeller is supported for rotation about the axis, the second impeller being movable along the axis relative to the second pump housing part;
• the first and second impellers when moved along the axis with the rotor assembly moving axially relative to the first and second pump housing parts to adjust the hydraulic performance characteristics of the first and second pumping stages.