Blood pump

An intravascular blood pump for percutaneous insertion into a patient's blood vessel, comprising:

• a pump casing having a blood flow inlet and a blood flow outlet,
• an impeller arranged in said pump casing so as to be rotatable about an axis of rotation, the impeller having blades sized and shaped for conveying blood from the blood flow inlet to the blood flow outlet,
• a drive unit for rotating the impeller, the drive unit comprising a magnetic core including a plurality of posts arranged about the axis of rotation and a back plate connecting the posts and extending between the posts in an intermediate area, and
• a coil winding disposed around each of the posts, the coil windings being controllable so as to create a rotating magnetic field,
• wherein the impeller comprises a magnetic structure arranged to interact with the rotating magnetic field so as to cause rotation of the impeller,
• wherein the magnetic core comprises or consists of layered sheets of soft magnetic material such that the soft magnetic material is discontinuous regarding electric conductivity in a cross-section transverse to the layered sheets,
• wherein an orientation of the sheets within the posts relative to the rotational axis is the same for all posts.