Ventilzeitpunktbestimmungs-Steuerungsvorrichtung für einen Verbrennungsmotor

摘要

The valve timing control system of the present invention comprises an actuator for changing an actual valve timing of an intake valve or an exhaust valve; an oil pressure adjusting unit for supplying operating oil to the actuator, and adjusting the oil pressure thereof; an actual valve timing control unit for controlling the actuator by controlling the oil pressure adjusting unit, so that the actual valve timing follows up a target value; and an oil temperature estimation unit for estimating the temperature of the operating oil, according to an operating state of the internal combustion engine from a previous operation, and according to its current operating state. Based on the estimated oil temperature, the actual valve timing control unit switches a control amount for controlling the oil pressure adjusting unit.