Patent ID: 6679206
Filing Date: 2004-01-20
Classification: F02D,F02M,Y02T

Abstract:
A control method of a valve condition control system for an internal combustion engine including a first variable valve drive mechanism for changing a valve condition of one of an intake valve and an exhaust valve and a second variable valve drive mechanism for changing a valve condition of the other of the intake valve and the exhaust valve, the valve condition control system being adapted to calculate a target control amount of each variable valve drive mechanism and to control an operation of each variable valve drive mechanism such that its actual control amount matches the target control amount, the control method comprising the steps of:calculating the control amount of the first variable valve drive mechanism required for obtaining an appropriate valve condition of one of the intake and exhaust valves for an engine operation state as a target control amount of the first variable valve drive mechanism; calculating a target valve overlapping amount between the intake and exhaust valves in accordance with the engine operation state; and calculating the target control amount of the second variable valve drive mechanism on the basis of an actual control amount of the first variable valve drive mechanism and the target valve overlapping amount.