Patent ID: 8312860

Claim:
Method of operating a four-stroke internal combustion engine including a variable volume combustion chamber defined by a piston reciprocating within a cylinder between top-dead center and bottom-dead center points, intake and exhaust passages, intake and exhaust valves controlled during repetitive, sequential exhaust, intake, compression and expansion phases of a combustion cycle, a direct injection fuel system and a spark ignition system, comprising: monitoring an engine operating state comprising an engine speed and an engine load; and selectively operating the engine in a multiple-injection, multiple-ignition combustion mode comprising three injection events based upon the engine speed and the engine load, the operating comprising: controlling a first injection event during a recompression period of the combustion cycle and a first ignition calibrated to the first injection event; controlling a second injection event effective to establish a homogeneous fuel charge prior to a main combustion, wherein the second injection event corresponds to a compression ignition event; and controlling a third injection event late in the compression phase of the combustion cycle and a second ignition calibrated to the third injection event.