Patent ID: 6305364
Filing Date: 2001-10-23
Classification: F02B,F02D,F02M,Y02T

Abstract:
A four stroke internal combustion engine having at least one intake valve and a corresponding intake port, and at least one exhaust valve and a corresponding exhaust port, said engine comprising:a fuel injection system having fuel injectors arranged in the intake port;a variable valve timing system for simultaneously opening, at least during pre-defined engine operating conditions, the intake and exhaust valves so as to enhance internal exhaust gas recirculation (EGR) by forcing a substantial quantity of exhaust gases back into the intake port, said variable valve timing system being operative, at least during the engine operating conditions, to prolong a valve overlap period defined as the time during which the intake and exhaust valves are simultaneously open; andfuel control means for controlling the timing of said fuel injectors to introduce substantially all of the injected fuel directly into the back flow of the internal EGR gases during the prolonged valve overlap period, the fuel being thermally conditioned by the internal EGR gases before being admitted into the combustion chamber during a subsequent intake stroke.