An apparatus for cleaning a surface of an optical window includes a first electrode that is provided inside the optical window and is covered with a dielectric material forming the optical window. A second electrode is provided around the optical window and is exposed on at least one surface of the optical window. A power supply is electrically coupled between the first electrode and the second electrode. The apparatus further includes a controller that controls the power supply so as to generate dielectric barrier discharge along the surface of the optical window by applying a high-frequency or pulsed voltage between the first electrode and the second electrode.

A control apparatus for a compression-ignition type engine is applied to an engine capable of carrying out partial compression ignition combustion in which an air-fuel mixture is subjected to CI combustion by self-ignition. The control apparatus creates a lean A/F environment where an air-fuel ratio as a ratio between air and fuel in a cylinder exceeds 20 and is lower than 35, or a lean G/F environment where a gas air-fuel ratio as a ratio between entire gas and the fuel in the cylinder exceeds 18 and is lower than 50 and the air-fuel ratio substantially matches a stoichiometric air-fuel ratio. Prior to planned timing of the CI combustion, in the lean A/F environment or the lean G/F environment, the control apparatus causes an ignition plug to generate a spark and to generate a high-temperature portion.

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. Timing of the preceding ignition is set to be more retarded when an engine speed is high than when the engine speed is low.

Apparatuses, methods, and systems for igniting fuel for an internal combustion engine, an ignition system include a first ignition device associated with a pre-combustion chamber of a cylinder and a second ignition device associated with a main combustion chamber of the cylinder. An engine control unit is operably connected to both the engine and the ignition system to ignite fuel for the cylinder with the first ignition device independently of igniting fuel with the second ignition device. The engine control unit determines an occurrence of a combustion condition and in response thereto (i) ignites fuel for combustion with both the first and the second ignition devices or (ii) ignites fuel for combustion only with the second ignition device. The engine control unit determines a second combustion condition and in response thereto ignites fuel only with the first ignition device.

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.

An engine includes a cylinder block in which a cylinder is formed, a piston arranged to be reciprocally movable in the cylinder, a cylinder head that is arranged on an upper side of the cylinder block and forms a combustion chamber between an inner peripheral surface of the cylinder and an upper surface of the piston, and an ignition plug arranged in the cylinder head. An inner peripheral portion of the cylinder head includes an inner peripheral side portion formed to be flush with the inner peripheral surface of the cylinder, and a tilting portion tilting from the upper surface of the piston to a side surface is formed on the piston.

An engine includes a cylinder block in which a cylinder is formed, a piston arranged to be reciprocally movable in the cylinder, a cylinder head that is arranged on an upper side of the cylinder block and forms a combustion chamber between an inner peripheral surface of the cylinder and an upper surface of the piston, and an ignition plug arranged in the cylinder head. An inner peripheral portion of the cylinder head includes an inner peripheral side portion formed to be flush with the inner peripheral surface of the cylinder, and a tilting portion tilting from the upper surface of the piston to a side surface is formed on the piston.

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.

A marine outboard engine includes an internal combustion engine assembly that includes an internal combustion engine, a fuse assembly, a fuel filter, a spark plug, a gearcase including one of a propeller and an impeller, a swivel bracket, and a cowling. The cowling includes a service panel disposed on a first lateral side of the internal combustion engine assembly, and an affixed panel disposed on a second lateral side of the internal combustion engine assembly. The service and affixed panels define a split line therebetween and are removably attached to each other. The fuse assembly, the fuel filter, and the spark plug are mounted to one of the first lateral side and the affixed panel proximate to the split line and are at least in part accessible from the first lateral side when the service panel is detached and removed from the affixed panel.

A marine outboard engine includes an internal combustion engine assembly that includes an internal combustion engine, a fuse assembly, a fuel filter, a spark plug, a gearcase including one of a propeller and an impeller, a swivel bracket, and a cowling. The cowling includes a service panel disposed on a first lateral side of the internal combustion engine assembly, and an affixed panel disposed on a second lateral side of the internal combustion engine assembly. The service and affixed panels define a split line therebetween and are removably attached to each other. The fuse assembly, the fuel filter, and the spark plug are mounted to one of the first lateral side and the affixed panel proximate to the split line and are at least in part accessible from the first lateral side when the service panel is detached and removed from the affixed panel.