Abstract: An internal combustion engine includes a plurality of cylinders defining combustion chambers each having a roof provided in the cylinder head. Each roof is composed of first and second inclined roof surfaces meeting in a ridge line. Two gas intake openings terminate in respective free edges on the first roof surface and at least one gas exhaust opening terminates in a free edge on the second roof surface. Respective gas exchange valves are seatable in the gas intake and gas exhaust openings. A fuel injection nozzle and a spark plug are supported in the cylinder head in a region of the roof. The first roof surface has, adjacent the fuel injection nozzle, a shoulder covering a terminal edge of the cylinders and extending into each combustion chamber. The shoulder has a front face transverse to the nozzle axis. The free edge of the gas intake openings intersects the ridge line.

Abstract: An internal-combustion engine includes a cylinder, a piston reciprocating therein, intake and exhaust ports, a fuel injection nozzle opening into the combustion chamber of the cylinder and an ignition device situated in the top wall of the cylinder. The top wall of the cylinder as well as the piston base oriented towards the top wall each has first and second surfaces being inclined to one another and meeting in a ridge, whereby the top wall and the piston base have an essentially V-shaped configuration when viewed in a sectional plane taken along the cylinder axis. The first surface of the top wall faces and is parallel with the first surface of the piston base and the second surface of the top wall faces and is parallel with the second surface of the piston base. A dished depression is provided in the piston base such that the depression interrupts the ridge and extends on either side thereof, whereby the dished depression is bounded by the first and second surfaces of the piston base.