Patent ID: 6474291
Filing Date: 2002-11-05
Classification: F01L,F02B,F02D,Y02T

Abstract:
A four-stroke reciprocating internal combustion engine comprising:a combustion chamber defined by a cylinder, a reciprocating piston contained within the cylinder, and a cylinder head; an exhaust port in fluid communication with the combustion chamber and an exhaust manifold, the exhaust port including an exhaust valve, the exhaust manifold being in fluid communication with an emissions control device; an intake port in fluid communication with the combustion chamber, the intake port being in fluid communication with a fuel injector for directing fuel into air in the intake port to form an air-fuel mixture, the intake port including an intake valve, the cylinder including a spark device for igniting the air-fuel mixture introduced into the combustion chamber through the intake port; at least one sensor for sensing at least one engine operating condition; and a controller, responsive to each sensor, for providing fuel injector control signals to the fuel injector for operating the fuel injector, for providing spark device control signals to the spark device for operating the spark device, and for providing valve control signals to a variable valve timing system for operating the exhaust valve and the intake valve, the controller executing a stored program to: (a) sense when the engine is in a shutdown condition, (b) thereafter cease fuel injection from the fuel injector, (c) thereafter operate the spark device to ignite the air-fuel mixture in the combustion chamber, (d) thereafter open the exhaust valve, and (e) thereafter close the exhaust valve after the reciprocating piston has been in upward motion for a time period, and (f) thereafter open the intake valve when the reciprocating piston is in downward motion, (g) thereafter close the intake valve after the reciprocating piston has been in downward motion for a time period, and (h) thereafter open the exhaust valve when the reciprocating piston is in upward motion.