A system composed of a water sleeve and a spark plug for an internal combustion engine. The spark plug has a supply passage, a center conductor, an insulator surrounding the center conductor, and a metallic body surrounding the insulator. A center electrode and at least one ground electrode form a spark air gap. In the region of its front end, the spark plug has an external thread for screwing the spark plug into a component of the internal combustion engine and has at least one discharge opening of the supply passage. The spark plug, at its front end, has, attached to the body, a sleeve that contains the external thread; the body has, on its outside, at least one groove that forms a section of the supply passage; and the sleeve has a heat conducting section that contains at least a part of the external thread and that is in contact with the body and covers at least portions of the groove.

A shielded igniter includes a positive-ignition source surrounded by a shield defining a shielded space. The shield includes an inlet hole, a first outlet hole and a second outlet hole. The shielded igniter is disposed within a cylinder of an internal combustion engine adjacent a fuel injector such that a first fuel jet is directed towards the inlet hole such that fuel enters the inlet hole and forms an ignitable fuel-air mixture. The positive-ignition source ignites the fuel within the shielded space such that combustion products exit the first and second outlet holes on a trajectory tangential to a circumference axisymmetric with a longitudinal axis of the fuel injector. Combustion products emanating from the first and second outlet holes ignite respective second and third fuel jets adjacent the first fuel jet on opposite sides thereof.

A hydrogen engine in which hydrogen gas is supplied into a combustion chamber as fuel, comprises: an injector for injecting hydrogen gas; a pressure accumulation chamber communicating with an injection hole of the injector; a communication hole communicating with the pressure accumulation chamber and the combustion chamber; and a pressure accumulation chamber defining portion provided between the injector and the combustion chamber and defining the pressure accumulation chamber and the communication hole. The pressure accumulation chamber defining portion is formed separately from the injector and has a thermal conductivity equal to or higher than a thermal conductivity of a combustion chamber wall defining the combustion chamber.

A hydrogen engine in which hydrogen gas is supplied into a combustion chamber as fuel, comprises: an injector for injecting hydrogen gas; a pressure accumulation chamber communicating with an injection hole of the injector; a communication hole communicating with the pressure accumulation chamber and the combustion chamber; and a pressure accumulation chamber defining portion provided between the injector and the combustion chamber and defining the pressure accumulation chamber and the communication hole. The pressure accumulation chamber defining portion is formed separately from the injector and has a thermal conductivity equal to or higher than a thermal conductivity of a combustion chamber wall defining the combustion chamber.

An improved apparatus for injecting and igniting fuel in an internal combustion engine includes a nozzle with a bore and a tip at a distal end. The bore includes a longitudinal axis and an annular valve seat. A needle reciprocates within the bore and in combination with the annular valve seat forms an injection valve where in a closed position the needle abuts the annular valve seat and in an open position the needle is spaced apart from the annular valve seat. A retainer axially protrudes from the tip of the nozzle along the longitudinal axis thereof whereby an annular mixing space extends between the retainer and the tip of the nozzle. There is an igniter secured to the nozzle that includes a positive-ignition source forming an ignition zone within a portion of the annular mixing space. Nozzle arrangements include those with both pilot hole and main holes in the nozzle extending between the plenum and outside the nozzle where the main hole longitudinal axis bypasses the retainer and a pilot fuel jet from the pilot hole(s) is retained and redirected such that an ignitable fuel-air mixture is formed within the annular mixing space. Nozzle arrangements also include nozzles with a plurality of main holes and no separate pilot holes in which the main longitudinal axis bypasses the retainer such that a main fuel jet is scraped by the retainer and scraped fuel is retained and redirected such that an ignitable fuel-air mixture is formed within the annular mixing space. The igniter is actuated to ignite the ignitable fuel-air mixtures.

An improved apparatus for injecting and igniting fuel in an internal combustion engine includes a nozzle with a bore and a tip at a distal end. The bore includes a longitudinal axis and an annular valve seat. A needle reciprocates within the bore and in combination with the annular valve seat forms an injection valve where in a closed position the needle abuts the annular valve seat and in an open position the needle is spaced apart from the annular valve seat. A retainer axially protrudes from the tip of the nozzle along the longitudinal axis thereof whereby an annular mixing space extends between the retainer and the tip of the nozzle. There is an igniter secured to the nozzle that includes a positive-ignition source forming an ignition zone within a portion of the annular mixing space. Nozzle arrangements include those with both pilot hole and main holes in the nozzle extending between the plenum and outside the nozzle where the main hole longitudinal axis bypasses the retainer and a pilot fuel jet from the pilot hole(s) is retained and redirected such that an ignitable fuel-air mixture is formed within the annular mixing space. Nozzle arrangements also include nozzles with a plurality of main holes and no separate pilot holes in which the main longitudinal axis bypasses the retainer such that a main fuel jet is scraped by the retainer and scraped fuel is retained and redirected such that an ignitable fuel-air mixture is formed within the annular mixing space. The igniter is actuated to ignite the ignitable fuel-air mixtures.

Disclosed is a valve ignition prechamber for an internal combustion engine which includes a combustion chamber in which a main load more or less diluted with a neutral gas is ignited, the prechamber including a lamination cavity into which an ignition unit opens and in which a lamination injector can inject under pressure an easily flammable pilot load, a lamination valve being able to close all or part of the lamination duct, in particular under the effect of the pressure of the gases prevailing in the combustion chamber.

Disclosed is a valve ignition prechamber for an internal combustion engine which includes a combustion chamber in which a main load more or less diluted with a neutral gas is ignited, the prechamber including a lamination cavity into which an ignition unit opens and in which a lamination injector can inject under pressure an easily flammable pilot load, a lamination valve being able to close all or part of the lamination duct, in particular under the effect of the pressure of the gases prevailing in the combustion chamber.

The object is to provide an injector with a built-in ignition device that can achieve downsize of device as a whole without changing significantly the structure of a fuel injection device. The injector with the built-in ignition device comprises an ignition device 3 and a fuel injection device 2. In the ignition device 3, an electromagnetic wave oscillated from an electromagnetic wave oscillator MW is boosted by a booster that is constituted by a resonance structure, a potential difference between a ground electrode 51 and a discharge electrode 31 is increased, and a discharge is caused. In the fuel injection device 2, a valve body part of a nozzle needle 24 is moved toward or away from a valve seat (orifis) 23a, and thereby, the fuel injection control is performed. Then, the resonance structure is formed by a dielectric member 30 that is connected to the electromagnetic wave oscillator and formed on the surface of a fuel injection pipe 21, and an inner wall surface 50a of a mounting port 50 for an injector of a cylinder head 5. A discharge electrode 31 is a projection that is formed on the surface of the fuel injection pipe 21, and a discharge is caused by making a position of the wall surface of the mounting port 5 that is closest to the discharge electrode 31 as a ground electrode 51.

The object is to provide an injector with a built-in ignition device that can achieve downsize of device as a whole without changing significantly the structure of a fuel injection device. The injector with the built-in ignition device comprises an ignition device 3 and a fuel injection device 2. In the ignition device 3, an electromagnetic wave oscillated from an electromagnetic wave oscillator MW is boosted by a booster that is constituted by a resonance structure, a potential difference between a ground electrode 51 and a discharge electrode 31 is increased, and a discharge is caused. In the fuel injection device 2, a valve body part of a nozzle needle 24 is moved toward or away from a valve seat (orifis) 23a, and thereby, the fuel injection control is performed. Then, the resonance structure is formed by a dielectric member 30 that is connected to the electromagnetic wave oscillator and formed on the surface of a fuel injection pipe 21, and an inner wall surface 50a of a mounting port 50 for an injector of a cylinder head 5. A discharge electrode 31 is a projection that is formed on the surface of the fuel injection pipe 21, and a discharge is caused by making a position of the wall surface of the mounting port 5 that is closest to the discharge electrode 31 as a ground electrode 51.