Patent ID: 6202601
Filing Date: 2001-03-20
Classification: F02B,F02D,F02M,Y02T

Abstract:
A method of introducing fuel into a combustion chamber of an operating four-stroke internal combustion engine having at least one cylinder with a piston, wherein said fuel comprises a main fuel and a pilot fuel that is more readily auto-ignitable than said main fuel, said method comprising:(a) detecting a set of load conditions on said engine;(b) employing a low load operating mode when a first predetermined set of load conditions is detected, and employing a high load operating mode when a second predetermined set of load conditions is detected, wherein an operable engine speed, said second set of load conditions corresponds to an engine load that is greater than the engine load corresponding to said first predetermined set of load conditions;(c) in said low load operating mode, introducing said pilot fuel and said main fuel into said combustion chamber when said cylinder is pressurized, when said piston is at or near top dead center;(d) in said high load operating mode comprises a three stage sequential introduction of said pilot fuel and said main fuel into said combustion chamber, whereby a first portion of said main fuel is introduced in a first stage during an intake or compression stroke, said pilot fuel is introduced in a second stage so that it ignites at the beginning of a power stroke, and a second portion of said main fuel is introduced in a third stage.