Patent ID: 7191744
Filing Date: 2007-03-20
Classification: F01L

Abstract:
1. An exhaust valve drive control method for controlling a closing operation of an exhaust valve in an internal combustion engine, comprising the steps of: first determining a current position of the exhaust valve and a rotation speed of the internal combustion engine, and then calculating a time at which a piston arrives at the current position of the exhaust valve on the basis of the current position and the rotation speed; starting the closing operation of the exhaust valve before the arrival time; calculating a time at which a gap between the exhaust valve and the piston reaches a first predetermined value on the basis of the rotation speed of the internal combustion engine, and stopping the exhaust valve closing operation temporarily when the time is reached; and calculating a time at which the piston arrives at the stopping position of the exhaust valve on the basis of the rotation speed of the internal combustion engine, and resuming the exhaust valve closing operation before the arrival time.