Patent ID: 8191519
Filing Date: 2012-06-05
Classification: F01L,F02D,Y02T

Abstract:
1. A method for controlling a spark-ignition direct injection internal combustion engine including intake and exhaust camshafts and intake and exhaust valves, the method comprising: providing a low-lift intake lobe and a high-lift intake lobe on the intake camshaft, said low-lift intake lobe and said high-lift intake lobe separated by a predetermined intake lobe separation angle; providing a low-lift exhaust lobe and a high-lift exhaust lobe on the exhaust camshaft, said low-lift exhaust lobe and said high-lift exhaust lobe separated by a predetermined exhaust lobe separation angle; operating the engine in a controlled auto-ignition combustion mode with a positive valve overlap using the high-lift intake and exhaust lobes; operating the engine in the controlled auto-ignition combustion mode with a negative valve overlap using the low-lift intake and exhaust lobes; and transitioning between operating the engine in the controlled auto-ignition combustion mode with positive valve overlap and the controlled auto-ignition combustion mode with negative valve overlap solely by switching between using the high-lift intake and exhaust lobes and the low-lift intake and exhaust lobes.