Abstract: An engine system is provided, which includes a cylinder block, a cylinder head, a piston, 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, and a controller electrically connected to the injector, the main spark plug and the subspark plug. When an engine speed is above a given reference engine speed, the controller controls, in a low-load range below a given reference load, the ignition devices so that the subignition is performed after the main ignition, and the controller controls, in a high-load range exceeding the reference load, the ignition devices so that only the subignition is performed, or so that the main ignition is performed at the same timing as or after the subignition.

Abstract: 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.

Abstract: An internal combustion engine for gaseous fuel includes a cylinder and a piston for reciprocal movement in the cylinder along a reciprocal axis, whereby a combustion chamber is at least partially delimited by the cylinder and the piston. The piston includes a piston crown facing the combustion chamber, a piston crown projection of the piston crown in a direction parallel to the reciprocal axis and onto a piston crown plane extending transversally to the reciprocal axis having a piston crown center point, the piston crown comprising a piston bowl surface defining a piston bowl and a piston rim portion enclosing the piston bowl surface. A piston bowl opening is the intersection between the piston rim portion and the piston bowl surface. The piston bowl opening has an opening center of gravity in the piston crown plane. The opening center of gravity is offset from the piston crown center point.

Abstract: Systems and methods for cold starting an internal combustion engine are described. In one example, the two amounts of fuel are injected into an engine cylinder during a cycle of the engine cylinder. The first amount of fuel is combusted to generate torque to rotate a crankshaft of the engine and the second amount of fuel is at least partially combusted in an exhaust system of the engine to increase exhaust gas temperature.

Abstract: A fuel supply system for an active pre-combustor, including a cylinder assembly. The cylinder assembly comprises a cylinder head, a cylinder body, and a piston. The cylinder head, the cylinder body and the piston form a main combustor. The fuel supply system for the active precombustor further includes a precombustion chamber assembly and a plunger air pump assembly. The pre-combustor assembly is communicated with the main combustor. The plunger air pump assembly is communicated with the pre-combustor assembly. The plunger air pump assembly can actively mix air with fuel into a mixed fuel and deliver it into the pre-combustor assembly (20). The fuel supply system for the active pre-combustor supplies the mixed fuel to the pre-combustor on the basis of a reciprocating stroke opposite to the piston by adding the plunger air pump assembly on the pre-combustor assembly, and is safe, reliable, and efficient.

Abstract: 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.

Abstract: A method for operating an internal combustion engine of a motor vehicle, where the internal combustion engine includes a combustion chamber and a prechamber spark plug which is assigned to the combustion chamber and which has a prechamber which is fluidically connected to the combustion chamber via a plurality of openings. The method includes operating the internal combustion engine in a catalytic converter heating operation in which an ignition time, at which an ignition spark for igniting a fuel-air mixture in the combustion chamber is generated in the prechamber within a particular operating cycle of the internal combustion engine, is shifted later compared to a normal operation. An injection time, at which a last direct fuel injection into the combustion chamber is carried out within the particular operating cycle, is a same in the catalytic converter heating operation and in the normal operation.

Abstract: Embodiments of the present invention provide a pre-combustion chamber assembly, comprising (a) a body, having a cylindrical end portion having a step-wise increase in diameter forming a sealing surface for sealing to an engine; (b) a tip, with a hollow shaft in fluid communication with a combustion region of the tip, where the shaft has a first shaft diameter that allows the shaft to be slid over a portion of the body; (c) a gasket mounted about the body and resting against the sealing surface, wherein the gasket comprises a wire wound washer.

Abstract: The objective is to obtain an internal-combustion-engine ignition apparatus that raises the ignitability at a time when a smolder occurs. An internal-combustion-engine ignition apparatus having a main combustion chamber and a subsidiary combustion chamber includes an ignition plug, an ignition coil having a primary coil, a secondary coil, and a tertiary coil, a first switching circuit that turns on or off energization of the primary coil, a second switching circuit that turns on or off energization of the tertiary coil, and a control apparatus that estimates a combustion state, that performs on/off-control of the first switching circuit so that a spark discharge is produced in the ignition plug and that performs on/off-control of the second switching circuit so that magnetic flux in the tertiary coil is changed so as to increase a secondary current, when deterioration of a combustion state has been estimated.

Abstract: 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.

Abstract: 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.

Abstract: The objective is to provide an internal-combustion-engine controller that can diagnose a smolder state in a subsidiary combustion chamber of a subsidiary-chamber-type internal combustion engine at low cost and in real time and that can perform control so as to securely produce a spark discharge. The controller controls an internal combustion engine in which a fuel-air mixture in the main combustion chamber is ignited with combustion gas to be injected through an orifice provided in a subsidiary combustion chamber; the controller includes an ignition plug and a detection probe arranged in the subsidiary combustion chamber, an ignition coil, a fuel injector, a smolder detector, and a smolder diagnosis device, and controls at least one of the ignition coil and the fuel injector in accordance with a diagnostic result in the smolder diagnosis device.

Abstract: A spark plug includes a tubular metal shell; an insulator including a locking portion locked onto the metal shell; and a cap disposed at a front end side of the metal shell, the cap having a plurality of orifices. The plurality of orifices include orifices with different cross-sectional areas. A sum of the number of one or more largest orifices and the number of one or more large orifices that have a cross-sectional area of larger than or equal to 90% of the one or more largest orifices is smaller than the number of orifices that are other than the one or more largest orifices and the one or more large orifices. A length of the front end portion in an axial direction between a front end of the insulator and a front end of the locking portion is smaller than or equal to 12 mm.

Abstract: Methods and systems are provided for a pre-chamber. In one example, a pre-chamber comprises a plurality of slots fluidly coupling it to a primary combustion chamber. The plurality of slots comprising a plurality of corresponding flaps configured to direct gases through the plurality of slots.

Abstract: A spark ignition engine includes: a pre-chamber (PC); a main chamber (MC); and a cylinder head coupled with a water jacket. The PC includes: a spark plug; and a PC body. The spark plug is surrounded by a jacket with thermal-conductive substance. The thermal-conductive substance is solid at room temperature and liquid at working temperature of the PC. At working temperature of the PC, the liquid thermal-conductive substance conducts heat from the spark plug to the water jacket. The PC body is coated with a layer of non-thermal-conductive substance.

Abstract: Methods and systems are provided for multiplexing ignition signals in an engine system based on engine operating conditions, each cylinder of the engine system including a main chamber spark plug and a pre-chamber system. In one example, a method may include multiplexing spark signals to a first spark plug and a second spark plug, the first spark plug coupled to a pre-chamber of a first cylinder and the second spark plug coupled to a main chamber of a second cylinder. In this way, one ignition coil may be used to actuate two different spark plugs coupled to separate cylinders.

Abstract: Methods and systems are provided for a prechamber. In one example, a system comprises a reservoir fluidly coupled to a prechamber and a compressor. The reservoir is configured to store boost air or residual gases.

Abstract: The present invention uses an improved engineered metal seal with or without an internal energized spring that is disposed in a pre-combustion chamber apparatus assembly to improve sealing over the flat washer seals that are currently used. The seals of the present invention comprise at least three different geometrical configurations of seals that are manufactured from titanium, Inconel, and/or hastelloy. The design of the tip and body of the pre-combustion chamber provide for movement of the seal without leaking. The sealing is provided on the axial surfaces of the tip and the body instead of the face of the tip and body by a flat washer seal, as is currently done.

Abstract: The present invention relates to a device and a method for controlling the start of an internal combustion engine, wherein the internal combustion engine is equipped with an ignition device comprising a fuel-fed prechamber to ignite an air-fuel mixture in a main combustion chamber. In order to reduce the emissions of the internal combustion engine during engine start a prechamber heating operations is performed by injecting a predetermined amount of fuel into the prechamber and igniting an air-fuel-mixture therein, while the main fuel injector is deactivated during at least a first engine cycle after engine start request.

Abstract: An internal combustion engine has a cylinder head having a cylinder roof defining first and second intake ports. The cylinder head supports a spark plug positioned between a central axis of the cylinder roof and a fuel injector. A combustion pre-chamber is connected to and extends outwardly from the roof. The pre-chamber encapsulates the spark plug, and is offset from the central axis and positioned between the central axis and the first and second intake ports. The pre-chamber defines an inlet aperture and an outlet aperture positioned along a spray streamline of the fuel injector, and defines first and second side apertures. Each side aperture is positioned adjacent to a respective one of the first and second intake ports. A method of operating an engine having a pre-chamber is also provided.

Abstract: A precombustion chamber gas engine includes a main-chamber forming portion forming a main combustion chamber, and a precombustion-chamber forming portion forming a precombustion chamber communicating with the main combustion chamber via a plurality of nozzle holes. The precombustion-chamber forming portion includes a cylindrical portion extending along an extension direction of a precombustion chamber central axis of the precombustion-chamber forming portion, and a tip portion closing a main-combustion-chamber-side end of the cylindrical portion and having the nozzle holes. The tip portion includes a thin region having a thickness T satisfying T<L where L is a length of each nozzle hole.

Abstract: A diesel engine employs a turbulent jet ignition system and method. In another aspect, diesel fuel and air are premixed prior to introduction of the mixture into a main engine combustion chamber. A further aspect employs a turbocharger compressor to boost air pressure into a main piston combustion chamber and/or an ignition pre-chamber for missing with a heavy fuel, such as diesel.

Abstract: Methods and systems are provided for a pre-chamber. In one example, a pre-chamber comprises a plurality of slots fluidly coupling it to a primary combustion chamber. The plurality of slots comprising a plurality of corresponding flaps configured to direct gases through the plurality of slots.

Abstract: The invention is provided with an ignition control section and an injection control section. When partial compression ignition combustion is carried out, the ignition control section causes an ignition plug to carry out: main ignition in which a spark is generated in a late period of a compression stroke or an initial period of an expansion stroke to initiate SI combustion; and preceding ignition in which the spark is generated at earlier timing than the main ignition. Also, when the partial compression ignition combustion is carried out, the injection control section causes an injector to inject fuel at such timing that the fuel exists in a cylinder at an earlier time point than the preceding ignition. Ignition timing of the preceding ignition is set to be more retarded when fuel concentration specified by a fuel concentration specification section is low than when the fuel concentration is high.

Abstract: Combustion cylinder (10) of an internal combustion engine, having a combustion chamber wall (20), which surrounds a combustion chamber (30), and a combustion chamber cover (40), which closes off the combustion chamber (30) on the upper side, wherein at least one inlet valve (50) for letting in a fluid is arranged on an inlet side (42) in the combustion chamber cover (40), and at least one outlet valve (60) for letting out a fluid is arranged on an outlet side (44) in the combustion chamber cover (40), wherein, furthermore, a prechamber spark plug (70) is arranged between the at least one inlet valve (50) and the at least one outlet valve (60) in the combustion chamber cover (40), which prechamber spark plug is arranged between the at least one inlet valve (50) and an injector (80) for injecting combustion fluid.

Abstract: Methods and systems are provided for increasing an amount of oxygen in a pre-chamber of a cylinder prior to combustion. In one example, a method may include purging residual gases from a pre-chamber to a cylinder via a pre-chamber air injection, and reducing a flow of the oxygen from the pre-chamber to the cylinder via a cylinder fuel injection directed toward an orifice fluidically connecting the pre-chamber with the cylinder. In this way, a composition of pre-chamber gases may be adjusted during a combustion cycle of a cylinder.

Abstract: An apparatus comprising a cylinder for an internal combustion engine having at least one combustion chamber and a squish area disposed at or around a base of the at least one combustion chamber, wherein the at least one combustion chamber comprises a paraboloidal cavity.

Abstract: Methods and systems are provided for a pre-chamber. In one example, a pre-chamber comprises a plurality of venturi passages fluidly coupling it to a primary combustion chamber. The plurality of venturi passages may be configured to assist in drawing out residual gases from a previous combustion event during a current combustion event.

Abstract: A spark plug is disclosed that includes at least one bore extending through a shell of the spark plug in order to form a passageway between an annular volume around the spark plug insulator nose and a pre-chamber volume of a pre-chamber device, thus directing a purge of exhaust gases trapped in the annular volume to a space formed by the exterior of the spark plug body and the interior of the pre-chamber device.

Abstract: In a spark-ignition internal combustion engine in which a protrusion including an intake-side inclined surface and an exhaust-side inclined surface is formed on a top surface of a piston, and a cavity is formed in the protrusion at a position associated with a spark plug, the intake-side inclined surface and the exhaust-side inclined surface are formed in such a way that an inclination angle of the exhaust-side inclined surface is smaller than an inclination angle of the intake-side inclined surface, and a difference in inclination angle between the intake-side inclined surface and the exhaust-side inclined surface is 4 degrees or larger.

Abstract: Methods and systems are provided for multiplexing ignition signals in an engine system based on engine operating conditions, each cylinder of the engine system including a main chamber spark plug and a pre-chamber system. In one example, a method may include multiplexing spark signals to a first spark plug and a second spark plug, the first spark plug coupled to a pre-chamber of a first cylinder and the second spark plug coupled to a main chamber of a second cylinder. In this way, one ignition coil may be used to actuate two different spark plugs coupled to separate cylinders.

Abstract: A pre-chamber spark plug having a shell, an insulator disposed at least partially within the shell, a center electrode disposed at least partially within the insulator, a ground electrode forming a spark gap with the center electrode, and a pre-chamber cap connected to the shell and forming a pre-chamber. The pre-chamber cap includes two or more openings that are configured so that at least one inflowing fuel-air mixture jet is directed to a pre-chamber wall gap so as to flush out or remove gas from a previous ignition cycle. The two or more openings are angled so that a first inflowing fuel-air mixture jet of a first opening does not intersect with a second inflowing fuel air-mixture jet of a second opening.

Abstract: An ignition control device includes a main ignition circuit to generate a spark discharge to a spark plug by controlling energization of a primary coil of an ignition coil for an internal combustion engine, an energy supply circuit that supplies energy based on a discharge continuation signal by controlling the energization of the primary coil during the spark discharge started by the operation of the main ignition circuit to supply a secondary current in the same direction as a main ignition continuously in a secondary coil of the ignition coil, a secondary current command circuit for outputting a command value of the secondary current based on the secondary current command signal, and an ignition control unit for setting signal values of the secondary current command signal and the discharge continuation signal.

Abstract: The invention relates to a drive-in device, comprising a drive-in piston, guided in a cylinder, for driving a nail member into a workpiece, and a combustion chamber arranged above the drive-in piston, said combustion chamber being Tillable with a combustion gas, wherein the combustion chamber has a bottom that is adjustable along an axis, wherein the bottom has a groove that extends in the circumferential direction and has an inserted seal which bears in a radial direction against a rigid combustion-chamber wall, wherein a front surface, in the axial direction, of the seal protrudes in the direction of the axis from a terminating plane of the groove.

Abstract: A diesel combustion system including a piston, an annular impinging block, and a combustion chamber. The combustion chamber is divided by the annular impinging block into an upper chamber and a lower chamber. The annular impinging block includes a lower guide surface that is adjacent to the lower chamber and that extends from a trough line connected to the piston to a crest line. The ratios among the inner diameter of the top of the piston, the outer diameter of the top of the piston, the diameter of the trough line, and the diameter of the crest line define the shape of the combustion chamber which leads to increased rate of combustion, reduced soot emission, and increased fuel efficiency.

Abstract: 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.

Abstract: An object is to provide a precombustion-chamber gas engine in which occurrence of knocking is restricted. The precombustion-chamber gas engine includes: a cylinder; a cylinder head; a piston delimiting a main combustion chamber with the cylinder head; a precombustion-chamber cap delimiting a precombustion chamber inside thereof and including a plurality of nozzle holes through which the precombustion chamber is in communication with the main combustion chamber; an intake valve for opening and closing an intake port that opens on the cylinder head; and an exhaust valve for opening and closing an exhaust port that opens on the cylinder head. In a planar view where the cylinder head is seen from below, there are at least one intake-side nozzle hole and at least one exhaust-side nozzle hole, and a total nozzle-hole area of the at least one intake-side nozzle hole is larger than that of the at least one exhaust-side nozzle hole.

Abstract: A laser igniter that avoids autoignition and soot formation within the prechamber and will minimize the formation of Nitrogen Oxides (NOx). The laser igniter has a laser spark plug with a microlaser and a prechamber integrally formed with the laser spark plug. The prechamber has six nozzle holes with three of the nozzle holes having a large diameter and three of the nozzle holes having a small diameter. The large and small nozzle holes are in a staggered arrangement.

Abstract: An ignition coil for an internal combustion engine includes an annular elastic seal which is tightly attached to a high-voltage tower and a plug installed in the high-voltage tower to be conductible with a spark plug. The elastic seal hermetically seals a gap between the high-voltage tower and the plug and also functions as a buffer to absorb stress, as exerted from the plug on a case of the ignition coil. This enables the case to be reduced in size as a whole without having to partially increase the wall thickness of the case to ensure a required degree of stiffness of the case and also results in improved degree of hermetic sealing between the plug and the high-voltage tower.

Abstract: A prechamber spark plug for igniting a fuel-air mixture in an internal combustion engine, in particular a gas engine, having a spark plug body (1) comprising a prechamber housing (2) and a cap (4) that closes the prechamber (3) at least partially, a ground electrode (10) and a central electrode (7) isolated from the ground electrode and projecting into the prechamber, is designed and developed with simple structural means in order to obtain advantageous igniting properties, the ground electrode (10) being designed for that purpose essentially as a cylindrical pin (11) that can be welded in a passage (12), preferably a bore (12), in the spark plug body (1).

Abstract: A pre-chamber is provided. In one embodiment, the pre-chamber is part of a two-stroke combustion engine having a cylinder head with a sparkplug receptacle that has a generally frustoconical shape, and the pre-chamber is coupled to the sparkplug receptacle. The pre-chamber may include a cooling jacket with a generally frustoconical shape and a combustion chamber having an upper zone and a lower zone, which may be narrower than the upper zone.

Abstract: A gasoline direct-injection engine is provided. The engine performs compression self-ignition combustion, and includes a cylinder, an injector, intake and exhaust ports, intake and exhaust valves, and an ozone generating system for generating ozone inside the cylinder. The system includes an electrode projecting into the cylinder while being partially electrically insulated from walls of the cylinder, and a high-voltage control device for applying a controlled pulse-shaped voltage to the electrode. When the voltage is applied, electric discharge occurs between the non-insulated part of the electrode and the walls of the cylinder, and ozone is generated inside the cylinder due to an effect of the electric discharge. A combustion pattern is provided, in which a compression stroke injection is performed and mixture gas formed by the fuel injection self-ignites to combust. When the combustion pattern is applied, the high-voltage control device is operated on intake stroke or the compression stroke.

Abstract: What is described is a method for igniting a fuel/air mixture in a combustion chamber of an engine, wherein a pencil, which is electrically insulated with respect to walls of the combustion chamber and contains a heating resistor, is electrically heated to a temperature of at least 800° C. in the combustion chamber of the engine by applying a heating voltage, and a high voltage of at least 500 V, which is different from the heating voltage, is applied to the pencil and thereby ions are generated in the combustion chamber by field emission of electrons. The invention additionally relates to an ignition system and a glow plug.

Abstract: A prechamber spark plug may have a prechamber having a pre-determined aspect ratio and hole pattern to achieve particular combustion performance characteristics. The aspect ratio and hole pattern may induce a rotational flow of fuel-air in-filling streams inside the prechamber volume. The rotational flow of the fuel-air mixture may include both radial flow and axial flow characteristics based on the aspect ratio and hole pattern. Axial flow characteristics can include a first axial direction proximate the periphery of the rotational flow and a counter second axial direction approaching the center of the rotational flow. The radial and axial flow characteristics may further include radial air-fuel ratio stratification and/or axial air-fuel ratio stratification. The rotational flow, the radial flow and the axial flow may be adjusted by alteration of the aspect ratio and hole pattern to achieve particular combustion performance characteristics in relation to a wide variety of spark gap geometries.

Abstract: A prechamber spark plug may have a prechamber having a pre-determined aspect ratio and hole pattern to achieve particular combustion performance characteristics. The aspect ratio and hole pattern may induce a rotational flow of fuel-air in-filling streams inside the prechamber volume. The rotational flow of the fuel-air mixture may include both radial flow and axial flow characteristics based on the aspect ratio and hole pattern. Axial flow characteristics can include a first axial direction proximate the periphery of the rotational flow and a counter second axial direction approaching the center of the rotational flow. The radial and axial flow characteristics may further include radial air-fuel ratio stratification and/or axial air-fuel ratio stratification. The rotational flow, the radial flow and the axial flow may be adjusted by alteration of the aspect ratio and hole pattern to achieve particular combustion performance characteristics in relation to a wide variety of spark gap geometries.

Abstract: A pre-chamber system for an internal combustion engine, in particular for a gas engine, includes a pre-chamber volume in which an ignitable fuel-air mixture can be fired by an ignition device which can be arranged at the pre-chamber system. The pre-chamber system has a flow transfer passage by which the pre-chamber volume can be connected to a main combustion chamber of the internal combustion engine. The pre-chamber volume includes an ignition region and a flow transfer region which is at least portion-wise delimited from the ignition region by an intermediate wall. The fuel-air mixture can be fired in the ignition region, and the flow transfer passage opens into the flow transfer region and there is provided an air feed passage. Preferably compressed air can be fed to the flow transfer region by way of the air feed passage.

Abstract: Methods, systems, and apparatuses are enclosed for an internal combustion engine system for industrial applications.

Abstract: A laser spark plug, in particular for an internal combustion engine of a motor vehicle, is described. A connection arrangement is provided in an end region of the laser spark plug facing the combustion chamber. The connection arrangement allow the laser spark plug to be connected to a prechamber module.

Abstract: A prechamber spark plug may have a prechamber having a pre-determined aspect ratio and hole pattern to achieve particular combustion performance characteristics. The aspect ratio and hole pattern may induce a rotational flow of fuel-air in-filling streams inside the prechamber volume. The rotational flow of the fuel-air mixture may include both radial flow and axial flow characteristics based on the aspect ratio and hole pattern. Axial flow characteristics can include a first axial direction proximate the periphery of the rotational flow and a counter second axial direction approaching the center of the rotational flow. The radial and axial flow characteristics may further include radial air-fuel ratio stratification and/or axial air-fuel ratio stratification. The rotational flow, the radial flow and the axial flow may be adjusted by alteration of the aspect ratio and hole pattern to achieve particular combustion performance characteristics in relation to a wide variety of spark gap geometries.

Abstract: An igniter system for a reciprocating piston internal combustion engine having one or more cylinders including at least one igniter per cylinder is disclosed. The igniter system can comprise: a combustion chamber connected to a main cylinder of the engine by a restricted diameter bore, wherein a lean burn fuel mixture is introduced into the combustion chamber by the normal compression stroke of the engine; a hydrogen valve that injects a hydrogen rich gas into the combustion chamber forming a mixture of hydrogen and air having a hydrogen concentration above the stoichiometric ratio for hydrogen and air in the combustion chamber; and a spark ignition source that injects hot unburned hydrogen into the main cylinder, thereby initiating ignition.