Abstract: A 2-cycle uni-flow spark-ignition engine has an annular scavenging chamber which is communicated with a crank chamber and which is connected to scavenging ports which are opened in an end period of downward stroking of a piston. A fluid introduced into the crank chamber is pre-compressed by the downward stroking of the engine and is discharged into a cylinder chamber through the annular scavenging chamber and the scavenging ports to form a uni-flow of scavenging fluid with a swirl above the piston. The engine has an exhaust valve provided on a cylinder head and normally opened by being driven with a predetermined force exerted by driving coiled spring towards the inside of the cylinder chamber.

Abstract: A two-stroke-cycle uniflow spark-ignition engine. A fluid sucked and pressurized by a compressor driven by the engine is delivered to an annular scavenging chamber formed in a cylinder around the entire circumference thereof, so as to be accumulated therein. The fluid within the annular scavenging chamber is discharged therefrom, through a plurality of scavenging ports formed in the cylinder and capable of opening into a cylinder chamber toward the end of a descending stroke of a piston, and/or into a recess which is above the piston, the discharged fluid serving as a scavenging fluid that flows generating a swirling uniflow. A mixture compressed within the cylinder chamber during an ascending stroke of the piston is ignited by an ignition plug for combustion.

Abstract: A fuel supply/ignition device for use with a stratified combustion system includes a fuel chamber formed adjacent to a combustion chamber. The fuel chamber is provided with a valve for supplying a liquid fuel and a spark plug for generating a spark. The spark plug is connected to a high-energy generator. When the liquid fuel is charged into the fuel chamber, and a high-energy discharge is generated by the spark plug, the liquid fuel in the fuel chamber is atomized to be sprayed into the combustion chamber, and is simultaneously ignited to provide stratified combustion. Application of the fuel supply/ignition device to an internal combustion engine contributes to a reduction in harmful components such as HC and NOx in an exhaust gas.

Abstract: A two-stroke-cycle uniflow spark-ignition engine generates power by pressurizing fluid introduced into a crank chamber within the crank chamber with a piston as it moves toward its bottom dead center, feeding the pressurized fluid to an annular scavenging chamber provided on the entire periphery of a cylinder where it accumulates, and discharging the fluid in the annular scavenging chamber into a cylinder chamber provided above the piston from a plurality of scavenging ports which are opened at the end of the descending stroke of the piston as a scavenging fluid in the form of a swirling uniflow.