Compression-ignition engine

Claim 1

A compression-ignition engine of the type having a cylinder, a piston having two cavities formed in the crown thereof and being reciprocably carried in the cylinder, a cylinder head closing one end of the cylinder and having an air inlet passage means for directing air into the closed end of the cylinder during an induction stroke of the piston, and a fuel injection nozzle means carried on the cylinder head for injecting fuel into the closed end of the cylinder near the end of a compression stroke of the piston, wherein the improvement comprises: the two cavities in the piston crown being cylindrical and forming two deep pan-shaped depressions which are spaced apart equidistantly on opposite sides of the center of the piston crown; the piston crown having a slot communicating the depressions, the slot having a depth extending substantially to the bottom of the depressions and having two parallel walls each of which extends tangentially from a respective cylindrical surface of each depression; and the fuel injection nozzle means having a discharge end projecting into the cylinder to a depth that the discharge end extends into one of the depressions in the piston crown at the end of the compression stroke of the piston.