Patent ID: 10920679

Abstract:
A method for controlling intake and exhaust valves of an engine includes: controlling, by an intake continuous variable valve timing (CVVT) device and an exhaust CVVT device, opening and closing timings of the intake valve and exhaust valves; determining, by a controller, a target opening duration of the intake and exhaust valves based on an engine load and an engine speed; modifying, by an intake continuous variable valve duration (CVVD) device and by an exhaust two-stage variable valve duration device, current opening and closing timings of the intake valve and exhaust valve based on the target opening durations. In particular, the exhaust two-stage VVD device switches a current opening duration of the exhaust valve to a first exhaust opening duration or a second exhaust opening duration which is shorter than the first opening duration based on the target opening duration of the exhaust valve.