ELECTROMAGNETIC DRIVE FOR A VENTRICULAR ASSIST DEVICE

摘要

An electromagnetic drive for use in a ventricular assist device. The electromagnetic drive provides adjustment to the device pressure according to the current through an electromagnet. The device includes a pair of U-shaped cores, each having a center section and two legs; one or more coils, each wound around a selected U-shaped core that, when electrically energized, generate a magnetic flux and define one or more pairs of magnetic poles each having a polar axis; and an armature between the U-shaped cores having two non-magnetic ends and a permanent magnet therebetween for generating a magnet force on the armature resulting from the attraction of the magnet to the U-shaped cores when the coils are not electrically energized. The drive geometry reduces lateral instability and device size and increases magnetic efficiency and linearity. Preferably, a coil is wound around each center section. Alternatively, the coils are wound around the legs.