An engine system is provided, which includes a main combustion chamber, a subchamber, an injector that injects fuel into the main combustion chamber, a main spark plug that ignites a mixture gas inside the main combustion chamber, and a subspark plug that ignites the mixture gas inside the subchamber, an throttle valve, and a control device. In a first range, compression self-ignition combustion of the mixture gas inside the main combustion chamber is performed. In a second range, flame propagation combustion is performed while setting an air-fuel ratio of the mixture gas lower than that in the first range. Immediately after the transition from the first range to the second range, only the subignition is performed, or the subignition and the main ignition are performed while setting a timing of the main ignition to a timing same as or retarded from the subignition.

A method includes providing an internal combustion engine having a combustion chamber, a piston movably disposed in the combustion chamber, and a prechamber connected to the combustion chamber via a flow port. The method further includes forcing a gas mixture from the combustion chamber through a zeolite material to the prechamber using a compression stroke of the piston, where the zeolite material filters the gas mixture to provide an oxygen rich gas into the prechamber.

A method includes providing an internal combustion engine having a combustion chamber, a piston movably disposed in the combustion chamber, and a prechamber connected to the combustion chamber via a flow port. The method further includes forcing a gas mixture from the combustion chamber through a zeolite material to the prechamber using a compression stroke of the piston, where the zeolite material filters the gas mixture to provide an oxygen rich gas into the prechamber.

A spark plug for an internal combustion engine includes a housing, an insulator, a center electrode, a ground electrode, and an auxiliary chamber forming portion. The ground electrode faces the center electrode from an outer peripheral side and forms a discharge gap between the ground electrode and the center electrode. An auxiliary chamber is formed inside the auxiliary chamber forming portion. A distance in an axial direction between the discharge gap and a distal end of the auxiliary chamber is equal to or greater than a maximum wall thickness of the auxiliary chamber forming portion. The auxiliary chamber forming portion includes injection holes. The injection holes are formed in a state where openings on an outer side are located closer to a distal end than openings on the auxiliary chamber side. At least one of the injection holes is an injection hole in the axial direction formed along an axial direction of a plug. When viewed in the axial direction of the spark plug, a center of the axial injection hole is eccentric from a central axis of the spark plug toward the discharge gap.

A fuel injection system for a spark-ignition internal combustion engine having a number of cylinders, where a plurality of respective main combustion chambers are defined; a number of first injectors and spark plugs coupled to the cylinders; a number of combustion pre-chambers, each obtained in the area of a respective spark plug; a number of extraction ducts, which originate from a respective cylinder to extract the gas mixture present inside the respective main combustion chamber; a reserve, where the gases extracted by the extraction ducts are mixed with the quantity of fuel needed to obtain a combustion under stoichiometric conditions inside the combustion pre-chambers; and a number of second injectors, each coupled to a respective combustion pre-chamber, into which it injects the gas-and-fuel mixture coming from the reserve.

A fuel injection system for a spark-ignition internal combustion engine having a number of cylinders, where a plurality of respective main combustion chambers are defined; a number of first injectors and spark plugs coupled to the cylinders; a number of combustion pre-chambers, each obtained in the area of a respective spark plug; a number of extraction ducts, which originate from a respective cylinder to extract the gas mixture present inside the respective main combustion chamber; a reserve, where the gases extracted by the extraction ducts are mixed with the quantity of fuel needed to obtain a combustion under stoichiometric conditions inside the combustion pre-chambers; and a number of second injectors, each coupled to a respective combustion pre-chamber, into which it injects the gas-and-fuel mixture coming from the reserve.

A cylinder head, for an applied-ignition reciprocating-piston internal combustion engine, includes a prechamber ignition system. The prechamber ignition system has a cavity in which an ignition device is arrangeable. The cavity is covered with respect to a combustion space of the reciprocating-piston internal combustion engine with a cover. The cover has at least two apertures which connect the cavity and the combustion space to one another in a gas-conducting fashion. The cavity is divided into a first ignition chamber and a second ignition chamber by a partition, and each ignition chamber is assigned an aperture.

A cylinder head, for an applied-ignition reciprocating-piston internal combustion engine, includes a prechamber ignition system. The prechamber ignition system has a cavity in which an ignition device is arrangeable. The cavity is covered with respect to a combustion space of the reciprocating-piston internal combustion engine with a cover. The cover has at least two apertures which connect the cavity and the combustion space to one another in a gas-conducting fashion. The cavity is divided into a first ignition chamber and a second ignition chamber by a partition, and each ignition chamber is assigned an aperture.

The present invention pertains to a pre-chamber body for an internal combustion engine. The pre-chamber body comprises a pre-chamber tip with a pre-chamber defined by an encircling side wall and at least one flow transfer passage fluidly connecting the pre-chamber and an exterior of the pre-chamber body (1), the flow transfer passage extending through the encircling wall, wherein the side wall is provided with at least one stiffness reduced section in proximity or adjacent to the flow transfer passage.

A prechamber sparkplug includes a housing having a nozzle with a prechamber formed therein, and each of a first set and a second set of electrode prongs within the prechamber. The second set of electrode prongs downwardly depend from attachment points to the housing, and form, together with the first set of electrode prongs, spark gaps within the prechamber. Each of the anode-cathode pairs formed by the sets of electrode prongs is spaced radially inward a clearance distance from the prechamber wall to position the spark gaps in a flow of swirled gases. The flow of swirled gases displaces a flame kernel formed at the spark gaps to inhibit quenching.