Patent ID: 10767516

Abstract:
A synchronous drive is provided in which a non-circular rotor generates a fluctuating corrective torque to counteract a fluctuating load torque on a driven rotor. The angular orientation of the non-circular rotor can vary relative to the driven rotor so as to change the phase angle of the fluctuating corrective torque relative to the driving rotor. The arrangement may be applied in internal combustion engines with variable valve timing (VVT) systems, wherein the phase angle of a fluctuating load torque presented on a cam rotor, due to forces arising from actuation of intake and/or exhaust valves by the camshaft, varies relative to the crankshaft. The phase angle of the fluctuating corrective torque is also varied relative to the crankshaft to maintain phase relationship with the fluctuating load torque and thereby maintain reduced cam torsional vibrations and span tensions provided by the non-circular rotor during operation.