Abstract: A second exhaust poppet valve 9 is provided in a portion of a combustion chamber expanded out of a main cylinder 1. A valve cover 7 reciprocates within a sub-cylinder 4 and covers a bottom surface of the second exhaust poppet valve 9. A first exhaust valve 10 and an intake poppet valve 11 are provided so as to face an upper surface of a piston 2. After the second exhaust poppet valve 9 is opened and hot high-pressure burned gas starts to flow away, the first exhaust poppet valve 10 is opened. As a result, the temperature of the first exhaust poppet valve 10 is reduced and the compression ratio can be increased. Then, a work amount of the piston is increased. The increased work amount compensates an amount of cooling loss due to increasing a surface area of the combustion chamber.

Abstract: An engine has an auxiliary cylinder 2 and a valve body 6 slidable in this cylinder. The valve body 6 has a gas space 7 formed in it. The engine further has an actuator for shifting the valve body 6 to switch the communication between the main combustion chamber and the gas space 7 and the isolation of the chamber and cavity from each other. The slidable valve may function as a compression ratio changer, which switches the communication and the isolation according to the load on the piston. In this case, the engine has a third compression ring 18. The slidable valve may also function as a suction or exhaust valve, which switches the communication between the combustion chamber and auxiliary passage and the isolation of the chamber and passage from each other during the suction or exhaust strokes. This improves the suction or exhaust efficiency of the engine.

Abstract: To achieve high compression ratio and lower temperature of the exhaust poppet valve in an engine provided with a poppet valve on an extend part of a combustion chamber outside a main cylinder, disclosed is a valve cover having a cylindrical side face and upper face, an compression ring either the cylindrical side face and an inner wall of the sub cylinder, means to contact closely a bottom face of a poppet valve and the upper face of the valve cover, the upper part of the valve cover occupying most part of the combustion chamber facing with the bottom face, the valve cover moves along with the poppet valve when the poppet valve is lifted, a combination of overhead valves and the poppet valve including one intake valve and one exhaust valve, and total number of the overhead valve and poppet valve is not less than 3.

Abstract: An engine has an auxiliary cylinder 2 and a valve body 6 slidable in this cylinder. The valve body 6 has a gas space 7 formed in it. The engine further has an actuator for shifting the valve body 6 to switch the communication between the main combustion chamber and the gas space 7 and the isolation of the chamber and cavity from each other. The slidable valve may function as a compression ratio changer, which switches the communication and the isolation according to the load on the piston. In this case, the engine has a third compression ring 18. The slidable valve may also function as a suction or exhaust valve, which switches the communication between the combustion chamber and auxiliary passage and the isolation of the chamber and passage from each other during the suction or exhaust strokes. This improves the suction or exhaust efficiency of the engine.

Abstract: According to a prepared program and the signal from a crank angle sensor, a computer switches two operation modes A and B in which an electric motor operates, and the computer creates a pair or pairs of different operation mode phases during the period from an ignition time to the next ignition time. As a result, the sum of the second period BB of the generating phase B and the first period AA of the succeeding driving phase A is long as compared with a conventional engine. If an initial period in an intake stroke or an exhaust stroke is set within the long period sum, it is possible to reduce intake loss or exhaust loss.

Abstract: A spark ignition internal combustion engine with improved anti-knocking function. The engine comprises: a cylinder; a cylinder head attached to an end of the cylinder; a piston slidably mounted in the cylinder, a center line of a piston pin of the piston is shifted on the thrust side of the piston with respect to a center line of an outer periphery of the piston; a main combustion chamber with an ignition plug; and a sub-combustion chamber with an inlet opening on an inner wall of the main combustion chamber facing an outer surface of the piston on the anti-thrust side thereof, area of the inlet opening is smaller than that of the outer surface.

Abstract: A Stratified Charge Engine where the main combustion chamber is made into one part of the cylinder head is described. The main combustion chamber in this engine is smaller than in Pre-Mixture Combustion Engines. Other main features of this engines are direct and simultaneous air/fuel injection, installation of a squish area and prevention of combustion in the end-gas zone. The thermal load and the weight of the piston in this engine are lower than in normal Stratified Charge Engines with fuel jet impingement. The fuel jet is kept inside the main combustion chamber, resulting in an higher anti-knocking quality of this engine as compared to Pre-Mixture Combustion Engines.

Abstract: A diesel engine using impingement and diffusion is described. In this diesel engine, both low smoke production and reduction of thermal load of the piston, as well as lighter construction of the piston, are realized. The main combustion chamber is situated in a part of the inner wall of the cylinder head. An impinging surface is made at the inner wall of the main combustion chamber in a way that the fuel jet after impingement, is dispersed from the edge of the impinging surface into the area of the main combustion chamber close to the squish area.

Abstract: A Stratified Charge Engine where the main combustion chamber is made into one part of the cylinder head is described. The main combustion chamber in this engine is smaller than in Pre-Mixture Combustion Engines. Other main features of this engines are direct fuel injection, installation of a squish area and prevention of combustion in the end-gas zone. The thermal load and the weight of the piston in this engine are lower than in normal Stratified Charge Engines with fuel jet impingement. The fuel jet is kept inside the main combustion chamber, resulting in an higher anti-knocking quality of this engine as compared to Pre-Mixture Combustion Engines.