Patent ID: 6176215
Filing Date: 2001-01-23
Classification: F02B,F02P,Y02T

Abstract:
A method for operation of a direct-injection spark-ignition internal combustion engine having one piston per cylinder and one injector per cylinder for injecting fuel into a combustion chamber comprising:forming a combustible fuel/air mixture with separately delivered combustion air, stratified charge operation being provided over large areas of a characteristics map of the internal combustion engine by injection of fuel centrally into the combustion chamber in a conical spray widening toward the piston during a compression stroke in a working cycle of a respective cylinder;igniting the mixture by applying an electrical flashover voltage between electrodes of a spark plug projecting into the combustion chamber, the ignition occurring in an edge region of the conical spray; andgenerating alternating voltage using an ignition system, so that high voltage rapidly builds up between the electrodes and triggers ignition sparks for the igniting step, wherein the high voltage triggering the spark is alternating voltage, and a spark duration being a function of an operating point.