Abstract: An internal combustion engine comprising a combustion chamber, an injection chamber connected thereto through an injection port, a secondary inlet passage opening to the injection chamber, and a secondary inlet valve for opening and closing the secondary inlet passage. A spark plug extends into the combustion chamber with the spark gap of the plug close to the injection port. At the suction stroke of the engine, air in the injection chamber is injected near to the spark gap through the injection port to blow away the combustion gas around the gap and also to generate a strong swirl and turbulence of the mixture in the combustion chamber, thereby improving firing and combustion of the lean mixture in the combustion chamber to reduce the discharge of noxious components in the exhaust gas and to improve the fuel consumption.

Abstract: A stratified charge spark ignition internal combustion engine is arranged to provide a preferably centered target recess on the end of the piston to redirect fuel spray injected against the recess back into the central portion of the combustion chamber to form a centralized relatively rich core or mixture cloud surrounded by an annular body of air. The size of the centered mixture cloud is load variable as determined by the volume and timing of injection as well as other factors. A preferred embodiment includes a target shape which compensates for limited eccentricity and angularity of the nominally axial injection spray to maintain a relatively even distribution of fuel within the mixture cloud. An alternative arrangement also includes a small ignition antechamber surrounding the end of the injection nozzle.

Abstract: An arrangement for air-compressing, direct-injection internal combustion engine having fuel ignition, at least one piston with a combustion chamber having a constricted throat and a pertaining cylinder having a pertaining cylinder head is disclosed. In this arrangement, the fuel injector and the combustion chamber of the piston are in communication with one another, the point of intersection of the longitudinal central axis of the fuel stream with the plane of the pertaining cylinder head which limits the upward movement of the piston is positioned within an imaginary circle having a diameter which is at most 1.1 times the greatest diameter of the combustion chamber, and the fuel injector is adapted to be located from the combustion chamber at a distance of up to about 30% of the greatest diameter of the combustion chamber.

Abstract: A precombustion type diesel engine having a modified and improved flame cup and precombustion chamber arrangement wherein a single side-opening passage in the floor of the flame cup is provided with dual throats connecting with the prechamber. The primary opening or throat controls swirl development during gas inflow to the prechamber while the secondary opening or throat allows early discharge of initial combustion products to the main combustion chamber for improved secondary mixing and reduced particulate emissions.

Abstract: A diesel engine has a transfer duct interconnecting a cylinder and a substantially toroidal precombustion chamber into which projects a fuel injector having four radially arranged, angularly equidistant nozzles, the fuel injector being coaxial with the generation axis of the precombustion chamber which is perpendicular to the axis of the cylinder.

Abstract: A two or four-stroke spark ignition engine has one or more fuel injectors located at or near BDC and/or in the inlet manifold, and an auxiliary chamber or recess in or adjacent to its cylinderhead to trap a lean mixture for causing more complete combustion of a rich mixture in the main chamber after the rich mixture is ignited.

Abstract: An internal combustion engine comprising an auxiliary chamber connected to a main chamber via a connecting passage. A raised portion is formed on the inner wall of the auxiliary chamber. The auxiliary chamber is divided into a first chamber and a second chamber. The connecting passage is tangentially connected to the inner wall of the second chamber at a position opposite to the raised portion with respect to the axis of the auxiliary chamber. A fuel injector having a pair of injection nozzles is arranged in the first chamber. One of the injection nozzles is directed to the tip of the raised portion. The other nozzle is directed to the inner wall of the auxiliary chamber, which is located at a position opposite to the raised portion with respect to the axis of the auxiliary chamber.