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, a subspark plug that ignites the mixture gas inside the subchamber, an exhaust gas recirculation (EGR) device and a control device. In a specific range where EGR is performed, the ignition devices are controlled so that a subignition timing is retarded from a main ignition timing, and an ignition phase difference that is a retard amount of the subignition timing from the main ignition timing becomes larger under a high EGR condition than a low EGR condition, the EGR conditions being conditions in the specific range where engine speeds are the same and EGR rates are different, and the high EGR condition being larger in the EGR rate than the low EGR condition.

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, a subspark plug that ignites the mixture gas inside the subchamber, an exhaust gas recirculation (EGR) device and a control device. In a specific range where EGR is performed, the ignition devices are controlled so that a subignition timing is retarded from a main ignition timing, and an ignition phase difference that is a retard amount of the subignition timing from the main ignition timing becomes larger under a high EGR condition than a low EGR condition, the EGR conditions being conditions in the specific range where engine speeds are the same and EGR rates are different, and the high EGR condition being larger in the EGR rate than the low EGR condition.

An internal combustion engine includes a combustion chamber with a cylinder head, a cylinder, and a piston. The internal combustion engine also includes at least one intake valve and at least one exhaust valve that are connected to the combustion chamber, a fuel injector that injects fuel into the combustion chamber, at least two ignition devices arranged in the combustion chamber, and control means that control the valves, the injector, and the ignition means. The control means operate the engine according to different combustion modes including a controlled ignition combustion mode, a compression ignition combustion mode, and an assisted compression ignition combustion mode. The control means activate the ignition means in the assisted compression ignition combustion mode.

A fuel combustion apparatus 2 according to the present invention includes: a combustion cylinder 4; a fuel feed unit 6 that introduces a swirling flow of an air-fuel mixture into the combustion cylinder; an ignition unit 10 including an igniter 32 located in the combustion cylinder 4; an ion detection unit 12 including a detector 40 located in the combustion cylinder 4; and a control unit 14 that adjusts a mixing ratio of the fuel based on a detection result obtained by the ion detection unit 12. Preferably, the fuel is ammonia. Preferably, the detector 40 is located in the vicinity of the igniter 32.

An internal combustion engine may include a combustion chamber which is delimited by a cylinder; an injector with which fuel can be injected into the combustion chamber, whereby a mixture comprising fuel and air can be generated in the combustion chamber; a pre-chamber, which is fluidically separate from the combustion chamber with the exception of a passage opening and which is fluidically connected to the combustion chamber via the passage opening; a first spark plug with which an ignition spark can be produced in the pre-chamber; and a second spark plug with which an ignition spark can be produced in the combustion chamber and outside of the pre-chamber, wherein the pre-chamber, the injector, and the second spark plug are arranged, in this order, in a direction extending in a plane that is perpendicular to the axial direction of the cylinder.

An internal combustion engine may include a combustion chamber which is delimited by a cylinder; an injector with which fuel can be injected into the combustion chamber, whereby a mixture comprising fuel and air can be generated in the combustion chamber; a pre-chamber, which is fluidically separate from the combustion chamber with the exception of a passage opening and which is fluidically connected to the combustion chamber via the passage opening; a first spark plug with which an ignition spark can be produced in the pre-chamber; and a second spark plug with which an ignition spark can be produced in the combustion chamber and outside of the pre-chamber, wherein the pre-chamber, the injector, and the second spark plug are arranged, in this order, in a direction extending in a plane that is perpendicular to the axial direction of the cylinder.

An internal combustion engine ignition device is provided for increasing the thermal efficiency of an internal combustion engine by increasing the spark length within the combustion chamber, wherein the spark can extend the width of the combustion chamber. The ignition device includes an ignition device housing to which a laser source is coupled. The laser source generates a laser beam capable of ionizing a fuel and/or an oxygen-containing gas used for combustion of the fuel in a combustion chamber. An electrical spark generator having a cathode electrode is coupled to the ignition device housing. The spark generator is configured for generating an electrical spark that emanates from the cathode within the combustion chamber and extends through the ionized fuel and/or ionized oxygen-containing gas, which may extend through the expanse of the combustion chamber, to a ground electrode within the combustion chamber to provide a more efficient and rapid fuel combustion within the combustion chamber.

A four-stroke opposed-piston engine contains a cylinder having a periphery and a combustion chamber and an ignition system, wherein the ignition system is fixed to the cylinder periphery and at least partially contained within the combustion chamber. During combustion, the ignition system is adapted to locate a spark within a fuel-rich predetermined region of the combustion chamber.

A four-stroke opposed-piston engine contains a cylinder having a periphery and a combustion chamber and an ignition system, wherein the ignition system is fixed to the cylinder periphery and at least partially contained within the combustion chamber. During combustion, the ignition system is adapted to locate a spark within a fuel-rich predetermined region of the combustion chamber.

A fuel combustion apparatus 2 according to the present invention includes: a combustion cylinder 4; a fuel feed unit 6 that introduces a swirling flow of an air-fuel mixture into the combustion cylinder; an ignition unit 10 including an igniter 32 located in the combustion cylinder 4; an ion detection unit 12 including a detector 40 located in the combustion cylinder 4; and a control unit 14 that adjusts a mixing ratio of the fuel based on a detection result obtained by the ion detection unit 12. Preferably, the fuel is ammonia. Preferably, the detector 40 is located in the vicinity of the igniter 32.