A controller for a spark plug of an engine is provided. The controller is configured to receive a signal indicative of an operational parameter of the engine. The controller is configured to define a breakdown time duration for the spark plug. Further, the controller is configured to determine an optimum amount of energy required to generate a spark for the spark plug based on the defined breakdown time duration and the operational parameter. The controller is further configured to cause the optimum amount of energy to be supplied to the spark plug to cause the spark to be generated for the spark plug.

To improve a propagation speed of a flame by effectively utilizing energy of the electromagnetic wave in the combustion chamber in an internal combustion engine that promotes combustion of fuel air mixture in a combustion chamber by means of an electromagnetic wave. The internal combustion engine includes, in addition to an internal combustion engine main body and an ignition device, an electromagnetic wave emission device and a control device. The electromagnetic wave emission device emits an electromagnetic wave to the combustion chamber while the flame is being propagated after ignition of the fuel air mixture. The control device controls a frequency of the electromagnetic wave emitted to the combustion chamber in view of a resonant frequency of the combustion chamber in accordance with an operation condition of the internal combustion engine main body or a propagation condition of the flame.

To improve a propagation speed of a flame by effectively utilizing energy of the electromagnetic wave in the combustion chamber in an internal combustion engine that promotes combustion of fuel air mixture in a combustion chamber by means of an electromagnetic wave. The internal combustion engine includes, in addition to an internal combustion engine main body and an ignition device, an electromagnetic wave emission device and a control device. The electromagnetic wave emission device emits an electromagnetic wave to the combustion chamber while the flame is being propagated after ignition of the fuel air mixture. The control device controls a frequency of the electromagnetic wave emitted to the combustion chamber in view of a resonant frequency of the combustion chamber in accordance with an operation condition of the internal combustion engine main body or a propagation condition of the flame.

An engine has an ignition source in a combustion chamber of the engine. An inner housing is provided that includes one or more jet apertures and defines an inner chamber containing the ignition source. An outer housing (or pre-chamber) is provided that includes one or more jet apertures in communication with the main combustion chamber and defines an outer chamber containing the inner housing.

An engine has an ignition source in a combustion chamber of the engine. An inner housing is provided that includes one or more jet apertures and defines an inner chamber containing the ignition source. An outer housing (or pre-chamber) is provided that includes one or more jet apertures in communication with the main combustion chamber and defines an outer chamber containing the inner housing.

Disclosed is a piston ported two-stroke compression ignition internal combustion engine comprising: a cylinder having a fixed closed end, and a piston for reciprocation within the cylinder, wherein the closed end of the cylinder and the piston together define a combustion chamber therebetween; at least one heater to heat the combustion chamber; and a controller to control the heater to heat the combustion chamber when the controller determines that a temperature of the combustion chamber has fallen below a threshold temperature during reciprocation of the piston within the cylinder.

An engine has an ignition source in a combustion chamber of the engine. An inner housing is provided that includes one or more jet apertures and defines an inner chamber containing the ignition source. An outer housing (or pre-chamber) is provided that includes one or more jet apertures in communication with the main combustion chamber and defines an outer chamber containing the inner housing.

A glow plug (1) provided with heater (2); tubular main metal shell (4) with shaft hole (43); conductive member (3) extending in the shaft hole toward a rear end side GK; metal terminal member (5) with one part (55) positioned in the shaft hole and another part (56) protruding from a rear end (48) of the main metal shell toward the rear end side GK, the terminal member including an enclosing portion (51) opened toward a front end side GS housing a rear end portion (32) of the conductive member and having electrical continuity with the rear end portion, the terminal member being disposed in the shaft hole while spaced apart from an inner peripheral surface 43m of the main metal shell; and sealing member (7) made of an insulator and airtightly sealing and insulating between the inner peripheral surface and the terminal member in the shaft hole.

A glow plug (1) provided with heater (2); tubular main metal shell (4) with shaft hole (43); conductive member (3) extending in the shaft hole toward a rear end side GK; metal terminal member (5) with one part (55) positioned in the shaft hole and another part (56) protruding from a rear end (48) of the main metal shell toward the rear end side GK, the terminal member including an enclosing portion (51) opened toward a front end side GS housing a rear end portion (32) of the conductive member and having electrical continuity with the rear end portion, the terminal member being disposed in the shaft hole while spaced apart from an inner peripheral surface 43m of the main metal shell; and sealing member (7) made of an insulator and airtightly sealing and insulating between the inner peripheral surface and the terminal member in the shaft hole.

Described is a glow plug with a glow pencil that comprises a forward end with a glow tip and a rearward end, a housing in which the rearward end of the glow pencil is arranged and in relation to which the glow pencil is movable in its longitudinal direction, and a bellows that is connected to the housing and the glow pencil. According to this disclosure, it is provided that a forward end of the bellows is attached to the housing and a rearward end of the bellows is attached to the glow pencil.