Patent ID: 6481394
Filing Date: 2002-11-19
Classification: F02B,F02D,F02P,Y02T

Abstract:
A two-cycle, internal combustion engine comprising a cylinder block that defines a cylinder bore, a cylinder head fixed at one end of the cylinder block enclosing one end of the cylinder bore, a crankcase member fixed at the other end of the cylinder block and enclosing the other end of the cylinder bore, the crankcase member forming a crankcase chamber, a piston positioned in the cylinder bore, a crankshaft rotably journaled in the crank case and driven by the piston, the piston, the cylinder bore, the cylinder head together defining a combustion chamber, at least one scavenge passage formed in the cylinder block for transferring an air charge compressed in the crankcase to the combustion chamber, the scavenge passage comprising a scavenge port configured such that reciprocating motion of the piston opens and closes the scavenge port, an exhaust passage formed in the cylinder block for discharging exhaust gases from the combustion chamber, the exhaust passage comprising an exhaust port configured such that the reciprocating motion of the piston opens and closes the exhaust port, a fuel injector mounted to inject fuel directly into the combustion chamber, the fuel injector comprising an actuator to regulate an amount of fuel injected by the fuel injector, an exhaust control valve extending into the exhaust passage and adapted to control the effective cross-sectional area of the exhaust port, an exhaust control valve position sensor that senses a position of the exhaust control valve, the position sensor being electronically connected to a control system, the control system comprising a controller that is configured to control the position of the exhaust control valve, the amount of fuel injected by the fuel injector, and to receive a signal from the exhaust control valve position sensor, the controller being further configured to increase the effective cross-sectional area of the exhaust port when an engine speed increases beyond a specified value and to adjust the amount of fuel injected into the combustion chamber based upon the sensed position of the exhaust control valve and the engine speed.