Abstract: An engine employs a dual mode combustion process including a first combustion mode for light loads utilizing premixed charge forced auto ignition (PCFA) wherein a pulse jet of reacting fuel mixture from a prechamber mixes with an ultra dilute premixed fuel-air charge in a main chamber, causing rapidly expanding combustion that ignites the remaining ultra dilute mixture by compression ignition. This improves efficiency, allows combustion phasing control and reduced NOx emissions. For higher speeds and loads, a conventional second combustion mode is utilized wherein a strong premixed mixture is ignited conventionally with spark ignition and/or pulse jet ignition. Cylinder pressures which would result from compression ignition at the higher speeds and loads are thus reduced providing overall engine operation with reduced emissions, improved fuel economy, and reduced noise through improved control of the combustion process.

Abstract: The present invention provides a fuel injector mounted on a side of a combustion chamber and delivers an ovalized fuel spray toward an oblong piston bowl of the chamber. The ovality of the spray is selected in relation to the oblong piston bowl and the motion of the combustion chamber air charge during the piston compression stroke to maintain the fuel charge within the piston bowl volume (including the space above the bowl) during compression and combustion of the fuel charge in the chamber. The shape of the oval spray may be adjusted as desired. In a specific embodiment, the ovality of the fuel spray indicated by the ratio of the major dimension to the minor dimension is in the range of about 2/1 to 4/1 for delivery into an oblong piston bowl with an ovality of about 1.2/1 to 1.5/1.

Abstract: An engine employs a dual mode combustion process including a first combustion mode for light loads utilizing premixed charge forced auto ignition (PCFA) wherein a pulse jet of reacting fuel mixture from a prechamber mixes with an ultra dilute premixed fuel-air charge in a main chamber, causing rapidly expanding combustion that ignites the remaining ultra dilute mixture by compression ignition. This improves efficiency, allows combustion phasing control and reduced NOx emissions. For higher speeds and loads, a conventional second combustion mode is utilized wherein a strong premixed mixture is ignited conventionally with spark ignition and/or pulse jet ignition. Cylinder pressures which would result from compression ignition at the higher speeds and loads are thus reduced providing overall engine operation with reduced emissions, improved fuel economy, and reduced noise through improved control of the combustion process.

Abstract: An internal combustion engine has a mechanism to control the compression ratio of the combustion chamber. The mechanism includes an eccentric journal bearing supporting each piston rod on the crankshaft of the engine. The journal bearing has a gear member secured thereto that meshes with an inner toothed profile of a ring gear which has an outer toothed profile that meshes with an engine-driven gear. The speed of the engine-driven gear is controllable through a differential gear mechanism to adjust the relative position of the eccentricity of the journal bearing relative to the crank throw on which it is supported. This will change the compression ratio of the combustion chamber of the engine. The mechanism, with a modification, can also be employed to control the maximum compression pressure or the maximum combustion pressure in the combustion chambers of engine.