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 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.

An air-assisted jet flame ignition device includes a housing, a fuel-air premixing unit, and a prechamber. The fuel-air premixing unit includes a fuel injector, an air injection valve, a premixing sleeve, a premixing sleeve inner core placed in the premixing sleeve, and a fuel injector fastening bolt. An inner wall surface of the premixing sleeve and an outer wall surface of the premixing sleeve inner core form a premixing sleeve inner cavity. An inner wall surface of the premixing sleeve inner core, a lower end surface of a nozzle of the fuel injector, and an upper end surface of an air inlet of the air injection valve form a premixing cavity. The premixing cavity coupled to the premixing sleeve inner cavity via a through hole on the sidewall of the premixing sleeve inner core. A prechamber nozzle is fixedly coupled to the lower part of the housing.

An air-assisted jet flame ignition device includes a housing, a fuel-air premixing unit, and a prechamber. The fuel-air premixing unit includes a fuel injector, an air injection valve, a premixing sleeve, a premixing sleeve inner core placed in the premixing sleeve, and a fuel injector fastening bolt. An inner wall surface of the premixing sleeve and an outer wall surface of the premixing sleeve inner core form a premixing sleeve inner cavity. An inner wall surface of the premixing sleeve inner core, a lower end surface of a nozzle of the fuel injector, and an upper end surface of an air inlet of the air injection valve form a premixing cavity. The premixing cavity coupled to the premixing sleeve inner cavity via a through hole on the sidewall of the premixing sleeve inner core. A prechamber nozzle is fixedly coupled to the lower part of the housing.

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 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 method for starting an internal combustion engine comprises the steps of: providing an internal combustion engine having at least one cylinder and a piston supported at a crankshaft for repeated reciprocal movement in the cylinder so as to define a main combustion chamber, the internal combustion engine further having an ignition device arranged in said cylinder with an igniter portion and a fuel injector which are both arranged at a pre-chamber, wherein the pre-chamber has a plurality of orifices for providing fluid communication between said pre-chamber and the main combustion chamber, injecting fuel in the pre-chamber, and igniting the injected fuel in the pre-chamber for pre-heating of the pre-chamber prior to injecting fuel in the main combustion chamber for combusting the injected fuel in the main combustion chamber.

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.

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.

Methods and systems are provided for a vehicle engine having a pre-chamber ignition system. In one example, a method may include adjusting one or more of an air injection amount and a fuel injection amount to a pre-chamber of an engine based on an air injection offset and a fuel injection offset learned while discontinuing fueling to cylinders of the engine and reducing air flow through the engine. In this way, air and fuel may be more accurately provided to the pre-chamber, thereby decreasing an occurrence of pre-chamber misfire.