Provided is an in-combustion chamber flow control device used in an engine having an intake passage connected to an intake opening formed in a ceiling surface of a combustion chamber, at an angle inclined with respect to a direction of an axis of a cylinder. This in-combustion chamber flow control device comprises a plasma actuator (28) disposed inside the combustion chamber (16). The plasma actuator comprises: a dielectric body (38) disposed along the ceiling surface (16a) of the combustion chamber, at a position closer to a center of the ceiling surface than the intake opening (18a); an exposed electrode (40) disposed on one side of the dielectric body facing the combustion chamber; and an embedded electrode (42) disposed on a side opposite to the exposed electrode across the dielectric body. The embedded electrode is disposed at a position closer to the intake opening than the exposed electrode.

An internal combustion engine with a piston having a piston head with a resonance cavity opening onto the head, and where a fuel nozzle located in a cylinder head is positioned to inject a fuel such as natural gas into the combustion chamber where resonance formed within the resonance cavity will ignite the fuel without the need of a spark plug. Inlet and exhaust ports in the cylinder head allow for air and combustion gas enter or leave the combustion chamber.

An aim of the present invention is, in a plug for high frequency emission disposed at an end of a casing having an emission antenna, to suppress a high frequency noise emitted from the emission antenna. The present invention is directed to a plug for high frequency emission including a transmission line for transmitting an electromagnetic wave, an emission antenna for emitting the electromagnetic wave supplied via the transmission line, and a casing constituted by a cylindrical shaped conductor, provided with the emission antenna at one end of the casing, and accommodating therein the transmission line extending from the emission antenna toward the other end of the casing. Inside of the casing, a central conductor electrically connected to the emission antenna and an outer conductor spaced apart from and surrounding the central conductor are embedded in an insulator so as to collectively constitute the transmission line, and the outer conductor is disposed in and held in non-contact with the casing.

A method for introducing microwave energy into a combustion chamber of an internal combustion engine in which the microwaves reach a combustion chamber through a microwave window, wherein the microwaves are run about a circumference of the combustion chamber and radially coupled into the combustion chamber after passing through the microwave window. Accordingly a device for introducing microwave energy into the combustion chamber of a reciprocating piston internal combustion engine with at least one cylinder with a cylinder head and a combustion chamber in the cylinder includes at least one circumferential annular hollow conductor cavity extending about the combustion chamber and including at least one feed for the microwave and at least one outlet opening for the microwave arranged between the annular hollow conductor cavity and the combustion chamber. An internal combustion engine includes the features of the device.

An ignition source for initiating combustion is provided. The ignition source includes an electrical delivery conductor mounted in a delivery conductor mounting structure. An electrical ground conductor is mounted in a ground conductor mounting structure and extends from the ground conductor mounting structure to a point proximate the delivery conductor to define an ignition spark gap between the delivery conductor and the ground conductor. At least one of the delivery conductor and the ground conductor is mounted so as to be positionable with respect to the other one of the delivery conductor and the ground conductor to selectively adjust a width of the ignition spark gap.

An ignition source for initiating combustion is provided. The ignition source includes an electrical delivery conductor mounted in a delivery conductor mounting structure. An electrical ground conductor is mounted in a ground conductor mounting structure and extends from the ground conductor mounting structure to a point proximate the delivery conductor to define an ignition spark gap between the delivery conductor and the ground conductor. At least one of the delivery conductor and the ground conductor is mounted so as to be positionable with respect to the other one of the delivery conductor and the ground conductor to selectively adjust a width of the ignition spark gap.

In a plasma generation device that generates electromagnetic wave plasma by emitting electromagnetic waves in a target space, the electromagnetic wave plasma is generated in a plurality of locations with a simple configuration and relatively low electromagnetic wave energy. The plasma generation device is provided with an antenna that emits electromagnetic waves supplied from an electromagnetic wave generator in the target space, a discharger that forcibly discharges free electrons from gas molecules in the target space, and an electric field concentration member that concentrates electric field of the electromagnetic wave emitted from the antenna. The electric field concentration member is arranged in non-contact relationship with the antenna. The plasma generation device causes the discharger to discharge free electrons and the antenna to emit electromagnetic waves, thereby generating electromagnetic wave plasma in the vicinity of the antenna and in the vicinity of the electric field concentration member.

In a plasma generation device that generates electromagnetic wave plasma by emitting electromagnetic waves in a target space, the electromagnetic wave plasma is generated in a plurality of locations with a simple configuration and relatively low electromagnetic wave energy. The plasma generation device is provided with an antenna that emits electromagnetic waves supplied from an electromagnetic wave generator in the target space, a discharger that forcibly discharges free electrons from gas molecules in the target space, and an electric field concentration member that concentrates electric field of the electromagnetic wave emitted from the antenna. The electric field concentration member is arranged in non-contact relationship with the antenna. The plasma generation device causes the discharger to discharge free electrons and the antenna to emit electromagnetic waves, thereby generating electromagnetic wave plasma in the vicinity of the antenna and in the vicinity of the electric field concentration member.

To reduce the amount of exhausted unburned fuel and further improve fuel efficiency of an internal combustion engine 10 provided with an ignition device 12 that ignites fuel air mixture more forcefully than a spark discharge in a combustion chamber 20. The internal combustion engine 10 includes an internal combustion engine main body 11 formed with the combustion chamber 20 and the ignition device 12 that ignites the fuel air mixture more forcefully than the spark discharge in the combustion chamber 20. In addition, the internal combustion engine 10 includes an electromagnetic wave emission device 13 that emits an electromagnetic wave supplied from an electromagnetic wave oscillator 32 from an antenna 41. The electromagnetic wave emission device 13 emits the electromagnetic wave from the antenna 41, thereby creating an electric field for accelerating a propagation speed of a flame.

An ignition device for an extraneously igniting combustion piston engine with an ignition chamber located between a cylinder head and a piston, wherein the cylinder head has an end surface which defines the ignition chamber and which is at least partially formed as a cylinder head electrode, and wherein an ignition chamber electrode is disposed within the ignition chamber and forms an ignition gap with the cylinder head electrode.