compression-ignition engine, in particular for light aircraft

A compression-ignition engine, suitable in particular for the propulsion of ligh aircraft, comprising:

• a crankcase accommodating a plurality of pistons, connected to and reciprocated in ordered sequence in banks on either side of a crankshaft disposed centrally in the crankcase;
• a plurality of cylinder heads corresponding in number to the pistons, associated and combining with the crankcase to establish a plurality of combustion chambers, each formed in the crown of the respective piston, of which the cross-sectional profile exhibits the shape of an upturned omega and the base presents a central bulge projecting back in the direction of the injector in such a way as to create a toroidal cavity directly in receipt of the injected fuel, of which the overall diameter is greater than the diameter of the rounded rim of the chamber established by the geometry of the omega profile;
• a plurality of valves supported by the cylinder heads and invested with reciprocating motion to the end of opening and closing corresponding air inlet and gas exhaust ports;
• a fuel injection system, comprising a plurality of spaced pump elements, arranged in two opposed banks equidistant from the camshaft, one for each of said plurality of cylinder heads, by which pump elements fuel is drawn from a tank and pumped through pipelines of identical length to a corresponding plurality of injectors, each carried by a respective cylinder head with one end penetrating directly into the respective combustion chamber and the remaining end connected to the respective pipeline;
• control means for driving said fuel injection system, comprising two rods disposed one at either side of and parallel to the camshaft and associated with each of said spaced pump elements of the fuel injection system, in such a way that all of the spaced pump elements are controlled simultaneously and uniformly by their movement, and a lever disposed transversely to and engaging one end of the two rods, pivoted at mid-point to and operated from outside the crankcase, by which the rods are invested with rectilinear motion;
• means for driving both the valves and the fuel injection system, said means for driving comprising one centrally located camshaft disposed longitudinally in the crankcase, parallel with and connected in timed rotation to the crankshaft by a train of three gears and operating synchronously with the pistons, by which one end of each of said spaced pump elements is engaged in direct contact.

A compression-ignition engine comprising:

• a crankcase accommodating a plurality of pistons reciprocated in ordered sequence and connected to a crankshaft extending in said crankcase;
• a plurality of cylinder heads corresponding in number to the pistons, said cylinder heads cooperating with said crankcase to establish a plurality of combustion chambers;
• a fuel injection system comprising a plurality of spaced fuel pump elements, one being provided for each of said cylinder heads, said pump elements drawing fuel from a fuel tank and pumping the fuel through respective pipelines to a respective one of a plurality of spaced fuel injectors, one injector being provided for each of said cylinder heads;
• and,
• a camshaft extending in said crankcase and spaced from said crankshaft, said camshaft including a plurality of longitudinally spaced fuel pump cams, one cooperating with a respective one of said plurality of spaced fuel pump elements.