Patent ID: 7105022

Claim:
An implantable left ventricular assist device which is implanted to a heart-diseased patient to assist the heart, the implantable left ventricular assist device comprising: an actuator for generating a linearly reciprocating driving force, wherein the actuator comprises a motor for generating a torque and a planetary gear assembly for reducing the torque of the motor; a pusher plate which performs a linearly reciprocating motion by the actuator; a blood sac which is contracted and expanded due to compression by reciprocating the pusher plate and the restoration of the blood sac; and a chamber for accommodating the blood sac, the pusher plate and the actuator, combining the same physically, and protecting the same within the body of a patient, wherein said actuator further comprises: a major axis which is driven by the motor, including a major axis gear at an end portion of the major axis, wherein the planetary pear assembly is threadedly engaged with the major axis gear; a minor axis, including a vessel-shaped fixing portion built in the center of the planetary gear assembly, and a cylindrical portion within which a pair of rollers are mounted on a predetermined position, while having a large cylindrical shape with respect to the fixing portion; a cylindrical cam which is inserted into the cylindrical portion of the minor axis, combined with the pusher plate, provided with a double cam groove along which the rollers move on an outer circumferential surface of the minor axis, and performs a linearly reciprocating motion according to the rotation of the minor axis; and a case and a rear cover which is provided with a ring gear threadedly engaged with the planetary gear assembly externally in a corresponding position, enables the motor and the minor axis to rotate together, and accommodates the cylindrical cam, the minor axis, the planetary gear assembly, the major axis and the motor.