Abstract: A reciprocating internal-combustion engine having at least two gas intake ports (3) with gas intake valves (6), at least one gas exhaust port (4) with a gas exhaust valve (7) and at least one ignition device (14) per cylinder (1) is provided. The engine can also include a combustion chamber (1.1) formed by a cylinder cover (2.1) and a crown (11.1) of a piston (11). A trough-shaped recess (12) can be provided in the piston crown (11.1) and is bounded by a trough base (12.1) and side walls (16). The recess (12) can intersect a roof ridge (11.2) on the piston crown (11.1) and the trough base (12.1) slopes towards a fuel injection nozzle (8) and ends in a wall zone (12.2) extending steeply upwards on its side facing the fuel injection nozzle (8).

Abstract: A reciprocating internal-combustion engine having at least two gas intake ports (3) with gas intake valves (6), at least one gas exhaust port (4) with a gas exhaust valve (7) and at least one ignition device (14) per cylinder (1), and having a combustion chamber (1.1) formed by the cylinder cover (2.1) and the crown (11.1) of the piston (11), which is guided in the cylinder (1) in a reciprocating manner, into which combustion chamber the gas intake ports open at a flat angle of less than 45 degrees, measured in relation to the cylinder-head plane (2.1), wherein the piston crown (11.1) on the one hand and the cylinder cover (2.1) on the other hand are substantially roof-shaped in vertical section, wherein in each case one of the roof surfaces is associated with the gas intake valves (6) and the other roof surface is associated with the gas exhaust valve (7), and the orientation of the roof surfaces of the cylinder cover (2.1) corresponds to the orientation of the roof surfaces of the piston crown (11.

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.