The ignition insert with an active pre-chamber (1) comprises an insert well (72) arranged in a cylinder head (3) of an internal combustion engine (2), said well (72) accommodating a cylindrical insert body (70) which is indexed in rotation and in which are arranged an ignition pre-chamber (71), an insert spark plug well (83) receiving a spark plug (12), and a injector radial orifice (88) which is aligned with a injector lateral well (73) arranged in the cylinder head (3) so as to receive an injector nose (16), said body (70) being terminated by a pre-chamber nose (75) opening into a combustion chamber (5), and being held in the insert well (72) by fixing means (82) cooperating with clamping means (74).

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 nozzle holes, and an ignition device disposed in the precombustion chamber and having an ignition portion spaced from the main chamber central axis 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 the precombustion chamber central axis and perpendicular to a straight line passing through the precombustion chamber central axis and the ignition portion. The cross-sectional area of a specific near nozzle hole which is at least one nozzle hole in the near-ignition region is smaller than the cross-sectional area of a specific far nozzle hole which is at least one nozzle hole in the far-ignition region.

A pre-chamber spark plug for a combustion chamber of an internal combustion engine includes a pre-chamber with a plurality of openings where the pre-chamber is fluidically connectable to the combustion chamber via the plurality of openings. The plurality of openings are configured to cause a tumbling flow of a fuel/air mixture flowing into the pre-chamber from the combustion chamber via the plurality of openings. At least two of the openings of the plurality of openings have diameters which differ from one another. At least two of the openings of the plurality of openings enclose angles from a main axis of the pre-chamber which differ from one another.

An internal combustion engine is provided with a pre-chamber provided inside a main combustion chamber. The pre-chamber includes an ignition plug, and a casing provided to a ceiling part to cover the ignition plug, the casing isolating an internal space formed therein from the main combustion chamber. A tumble flow of a mixture gas is formed inside the main combustion chamber. A plurality of communicating holes are formed in the casing, and include a first communicating hole opening to an intake port side and a second communicating hole opening to an exhaust port side. The tumble flow flowing into the pre-chamber through the first communicating hole forms in the pre-chamber a vortex flowing in the opposite direction from the tumble flow. The main combustion chamber is provided with a structure configured to suppress a flow opposing the vortex flowing into the pre-chamber through the second communicating hole.

A passive ignition pre-chamber for an internal combustion engine. The pre-chamber is typically implemented as a cap on the electrode end of a spark plug, and encloses a pre-chamber volume in which fuel is mixed with air to form a consistently ignitable mixture. The pre-chamber is passive in the sense that gas exchange with the engine's main combustion chamber is realized by local flow fields near nozzles into the main chamber and by pressure differences between the pre-chamber and the main chamber. The nozzles are sized such that at least one of the nozzles has a larger diameter than the remaining nozzles, as optimized using flow field and pre-chamber turbulence analysis.

A method of providing a passive ignition pre-chamber for an internal combustion engine. The pre-chamber is typically implemented as a cap on the electrode end of a spark plug and encloses a pre-chamber volume in which fuel is mixed with air to form a consistently ignitable mixture. The pre-chamber is passive in the sense that gas exchange with the engine's main combustion chamber is realized by local flow fields near nozzles into the main chamber and by pressure differences between the pre-chamber and the main chamber. The nozzles are sized such that at least one of the nozzles has a larger diameter than the remaining nozzles, as optimized using flow field and pre-chamber turbulence analysis.

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.

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.