Abstract: An internal combustion engine has at least one cylinder, wherein in the cylinder there is a piston, which has a recess. Furthermore, the internal combustion engine has a cylinder head, which has the shape of a roof complementary to the roof-shaped geometry of the piston with a first and second side converging in the shape of a gable, with the piston and the cylinder head defining a top side and a bottom side of a combustion chamber. The internal combustion engine has an ignition device, which is arranged at least approximately in the center in the roof shape. The cylinder further has preferably two inlet valves, which are arranged in the first side, and also preferably two outlet valves, which are arranged in the second side. The recess extends past both sides, wherein the recess includes at the side approximately vertically descending sides and a base. The piston further has at least two, preferably four quench zones, which are at least partially separated from each other by valve pockets for valves.

Abstract: An internal combustion engine has at least one cylinder, wherein in the cylinder there is a piston, which has a recess. Furthermore, the internal combustion engine has a cylinder head, which has the shape of a roof complementary to the roof-shaped geometry of the piston with a first and second side converging in the shape of a gable, with the piston and the cylinder head defining a top side and a bottom side of a combustion chamber. The internal combustion engine has an ignition device, which is arranged at least approximately in the center in the roof shape. The cylinder further has preferably two inlet valves, which are arranged in the first side, and also preferably two outlet valves, which are arranged in the second side. The recess extends past both sides, wherein the recess includes at the side approximately vertically descending sides and a base. The piston further has at least two, preferably four quench zones, which are at least partially separated from each other by valve pockets for valves.

Abstract: An ignition method for a multi-cylinder reciprocating gas engine wherein, in order to start a combustion cycle, a compressed, substantially homogeneous and not self-igniting combustion gas-air mixture contained in the corresponding cylinder chamber to be fired is ignited by the direct injection of a small amount of combustion gas. The injected small amount of combustion gas, which serves as the ignition gas, is injected onto a hot surface in the region of the combustion chamber. The beginning of the injection is predetermined depending on the position of the crankshaft, and is controlled by an engine control unit.

Abstract: A piston for an internal-combustion engine has a longitudinal axis, a crown and an outer crown face. The crown face includes a dished depression; a surface region surrounding the dished depression and being elevated relative thereto; and a plurality of substantially radially extending clefts subdividing the surface region into a plurality of elevated partial surface regions.