Abstract: A direct injection internal combustion engine of compression ignition type is provided with a piston cavity offset from the piston center and with an injection nozzle which injects a hollow conical fuel spray having a tangential velocity component and relatively weak penetration into a swirl set up in the combustion chamber. The injection geometry and the offset are such that squish and swirl flows interact to form an excellent air-fuel mixture over the whole volume of the cavity without forming local fuel concentrations or wetting the cavity wall.

Abstract: There is provided an alcohol internal combustion engine with direct injection and controlled ignition comprising a combustion chamber defined by a reciprocating piston and a flat cylinder head. The cylinder head supports a spark plug and an injector. In the dome of the piston is formed a cup disposed with respect to the intake valve so that the gases are set in rotation in the cup. The spark plug is placed in the cylinder head so that its electrodes are in the vicinity of the periphery of the cup where a rich mixture is produced by stratification at the end of compression. To further improve the stratification and the turbulence, favorable to complete and rapid combustion, a ramp may be provided around a fraction of the periphery of the cup.

Abstract: A direct-injection internal combustion engine has a rotationally symmetric combustion chamber which is located in the crown of a piston. Air for combustion is admitted into the combustion chamber in such a manner as to circulate about the axis of the latter. Fuel is injected into the combustion chamber through a discharge passage as a function of the engine load and speed. Within the upper range of engine load and speed, the fuel is injected as a concentrated jet and virtually all of the fuel is deposited upon the wall of the combustion chamber. The fuel evaporates from the wall and then mixes with the circulating air. In the lower range of engine load and speed, as well as during idling, the fuel is injected in the form of a finely atomized jet and mixes with the circulating air directly. The effective cross-sectional area of the fuel discharge passage in the lower range of engine load and speed is maintained between about 3 and 15% of the effective cross-sectional area at maximum output.

Abstract: A four-stroke piston engine in which air is drawn into a cylinder while rotary motion about the cylinder axis is imparted to the air. Fuel may be blown/injected into the air during its rotation in the cylinder while the fuel supply is located on the axis of the cylinder and supplies at least one jet of fuel directed radially outwardly and which jet of fuel in cooperation with the rotating air forms at least one helical stream of mixture within the cylinder, preferably during the compression stroke, which is transformed into a coherent mixture zone enclosed by a ring of air upon completion of compression. The piston may have a recess in the upper end into which the fuel nozzle is received when the piston approaches top dead center so that an enriched region is formed in the recess which can be ignited by electrodes disposed adjacent the recess.

Abstract: A combustion process for a stratified charge reciprocating internal combustion engine having a high pressure fuel injection system with two injectors discharging into the combustion chamber; the fuel from the first nozzle is ignited as it discharges and the heat from the burning fuel raises the temperature and pressure and chemically conditions the gas in the combustion chamber so fuel from the second injector is auto ignited as it is discharged into the combustion chamber. To provide the two injections of fuel, a simplified, electrically triggered, accumulator type multi-fuel injection system is preferred.

Abstract: A method for the pilot injection of fuel in a direct injection diesel engine with a depression in the tops of the pistons. The pilot fuel, of relatively high cetane number, e.g. diesel fuel, is sprayed prior to the main spray, obliquely from the side into the piston depression in a direction counter to the rotation of the intake air. Thereafter, during the same combustion cycle, the main spray, of lower cetane number, e.g. methanol, is sprayed in a zone around the center axis of the piston depression. A substantial reduction in pollutants is achieved.

Abstract: A fuel injection system for direct injection diesel engines with a depression in the tops of the pistons. A first injection pump has a regulator and accompanying first injector for each cylinder, the injectors being disposed to spray the fuel in a zone around the center axis of the respective piston depression. A second injection pump has a regulator and accompanying second injector for each cylinder, the second injectors being disposed to inject fuel obliquely from the side into the respective piston depression in a direction counter to the rotation of the intake air before the fuel from the first injectors is injected.

Abstract: A two cycle, spark ignition internal combustion engine of the class having a combustion chamber divided into a relatively small ignition region and a larger combustion region including the cylinder and piston is defined. Substantially stoichiometric fuel-air mixtures are independently supplied to the ignition region in substantially fixed quantity and to the larger region in variable quantity and compressed simultaneously so that the mixtures remain completely separated prior to ignition. The mixtures are stratified with respect to excess air supplied to both regions and to exhaust gases in the engine cylinder, and combustion initiated in the ignition region ignites the variable-sized mixture in the larger region. Burning proceeds from stoichiometric mixtures to lean mixtures as the stratified excess air is mixed into the burning gases. When no fuel is supplied to the large region, the small region functions independently and burns its fuel efficiently.