A pre-chamber arrangement (100) for a gas engine (1), including a pre-chamber body (20) accommodating a volume (30); and an inlet passage (40) with an inlet port (42), for supplying a gaseous medium (50) into the pre-chamber volume (30); the pre-chamber volume (30) extends in a longitudinal direction (L) between a top end (32) and a bottom end (34); the pre-chamber volume (30) is configured to accommodate an end of a spark plug (60) at the top end (32) and at the bottom end (34), the pre-chamber body (20) has openings (26) for allowing gas to flow between the pre-chamber volume (30) and a main combustion chamber (10) of the gas engine (1); the inlet port (42) is positioned, at a distance (D) from the top end (32) of the pre-chamber volume (30), in the longitudinal direction (L), such that a volume of residual gases is trapped at the top end of the pre-chamber volume when the gaseous medium is supplied into the pre-chamber volume during an intake stroke.

A pre-chamber spark plug for a combustion chamber of a combustion engine includes a pre-chamber which has a plurality of openings and an electrode device which is disposed in the pre-chamber. An ignition spark for igniting a fuel-air mixture introduced into the pre-chamber is generatable at a spark location in the pre-chamber by the electrode device. The pre-chamber spark plug is configured to bring about a tumble-shaped flow of fuel-air mixture flowing into the pre-chamber via the plurality of openings. The tumble-shaped flow has, in a first region of the pre-chamber, a first flow part pointing upward away from the plurality of openings, and, in a second region of the pre-chamber, a second flow part adjoining the first flow part and pointing downward in a direction of the plurality of openings. The spark location is disposed at least in part in the second region.

A pre-chamber spark plug for a combustion chamber of an internal combustion engine includes a pre-chamber which has a plurality of openings. A fuel-air mixture is introducible from the combustion chamber into the pre-chamber via the plurality of openings. With respect to an imaginary plane running in a longitudinal extension direction of the pre-chamber and dividing the pre-chamber into a first half and a second half of equal size, first openings are disposed in the first half and second openings are disposed in the second half. The first openings enclose a respective first angle with the imaginary plane, the second openings enclose a respective second angle with the imaginary plane, and a mean value of the first angles is greater than a mean value of the second angles. The plurality of openings are configured rotationally asymmetrically about an imaginary axis running on the imaginary plane.

A pre-chamber spark plug includes a shell extending along a longitudinal axis and comprising an inner surface. The pre-chamber spark plug further includes an insulator including an outer surface. The pre-chamber spark plug further includes a pre-chamber cap connected to the shell. The pre-chamber cap and the shell together forms a pre-chamber. The pre-chamber spark plug further includes an annular reservoir defined between the outer surface of the insulator and the inner surface of the shell. The annular reservoir is spaced apart from the pre-chamber with respect to the longitudinal axis. The pre-chamber spark plug further includes a plurality of projections disposed between the annular reservoir and the pre-chamber with respect to the longitudinal axis. The plurality of projections at least partially define a plurality of flow passages therebetween.

A prechamber spark plug. The spark plug includes a housing, a cap, which defines a prechamber at least partially, and which includes a plurality of through holes that are configured to produce a connection between the prechamber and a combustion chamber of an internal combustion engine; the through holes each having a hole center line; the cap including a recess at a region pointed towards the housing, the recess abutting the housing at a combustion-chamber-side end of the housing; a distance from an exit point of a through hole lying on the hole center line, to a recess, being in a range of 2 mm to 7 mm; and a first angle between a center axis of the prechamber spark plug and the hole center line being in a range of 30° to 70°. An internal combustion engine including such a prechamber spark plug is also described.

A precombustion chamber gas engine includes a main-chamber forming portion forming a main combustion chamber, a precombustion-chamber forming portion forming a precombustion chamber communicating with the main combustion chamber via a plurality of nozzle holes, and an ignition device disposed in the precombustion chamber and having an ignition portion spaced from a main chamber central axis of the main combustion chamber at a predetermined distance. In a plan view, the precombustion chamber has a near-ignition region including the ignition portion and a far-ignition region opposite to the near-ignition region separated by a borderline passing through a precombustion chamber central axis of the precombustion chamber and perpendicular to a straight line passing through the precombustion chamber central axis and the ignition portion. The distance between the precombustion chamber central axis and a precombustion-chamber-side opening end, connected to the precombustion chamber, of a specific far nozzle hole which is at least one nozzle hole in the far-ignition region is shorter or longer than the distance between the precombustion chamber central axis and a precombustion-chamber-side opening end of a specific near nozzle hole which is at least one nozzle hole in the near-ignition region.

The invention relates to an engine having prechamber ignition, in particular a gas engine, that comprises a main combustion space in a cylinder of the engine for combusting an air-fuel mixture and a prechamber having an ignition device arranged therein and a fuel injector arranged therein, wherein the prechamber has at least one transfer port that fluidically connects the prechamber to the main combustion space. The engine is characterized in that the fuel injector arranged in the prechamber is the only fuel injector via which fuel can be introduced into the associated main combustion space.

A pre-chamber spark plug for a combustion chamber of an internal combustion engine includes a pre-chamber which has a plurality of openings and which is fluidically connectable to the combustion chamber via the plurality of openings. A fuel/air mixture is introducible from the combustion chamber into the pre-chamber via the plurality of openings. Each of the plurality of openings has a respective flow cross section through which the fuel/air mixture is flowable. With respect to an imaginary plane running along an imaginary axis of the pre-chamber and dividing the pre-chamber into a first half and a second half of equal size, a sum of the flow cross sections of first openings disposed in the first half is greater than a sum of the flow cross-sections of second openings disposed in the second half.

A pre-chamber spark plug has a pre-chamber which has openings, where, with respect to a first plane running in the longitudinal direction of the pre-chamber and dividing the pre-chamber into two halves of equal size, first openings are disposed in a first of the halves and second openings are disposed in a second of the halves. The first openings are spaced apart from a second plane running in the longitudinal direction of the pre-chamber and extending perpendicular to the first plane by a first angle in the circumferential direction of the pre-chamber. The second openings are spaced apart from the second plane by a second angle in the circumferential direction of the pre-chamber. The mean value of the first angles is smaller than the mean value of the second angles.

In certain embodiments with large size prechambers and/or with prechambers that have large spark-gap electrode assemblies, a poor scavenge of the crevice volume may cause deterioration of the preignition margin, which then may limit the power rating of the engine, may cause the flow velocity field of the fuel-air mixture to be excessively uneven and may result in the deterioration of the misfire limit. One or more auxiliary scavenging ports may allow admission of fuel rich mixture to the crevice volume, thereby cooling the residual gases and preventing occurrence of preignition. More organized and powerful flow velocity fields may be obtained in the spark-gap electrode assembly region. This condition may result in a significant extension of the flammability limit and may significantly improve the combustion efficiency of the prechamber. Passive prechambers using the active scavenge concept may increase the engine power output and reduce the emission of pollutants from engine combustion.