Abstract: An internal combustion engine in one embodiment includes a number of cylinders each having a crank piston connected to an engine crankshaft and disposed within a combustion chamber. Each cylinder includes a valve seat projecting inward from cylinder wall offset from the top dead center position of the crank piston. A free piston is slidingly disposed within the cylinder between the head end and the valve seat. The free piston has an outer diameter that is less than the inner diameter of the cylinder to permit leakage of combustion gas past the free piston. The free piston also includes a lower face opposing the crank piston with an annular groove defined in the lower face configured for sealing engagement with the valve seat. The free piston defines a pressure chamber that is pressurized during the by combustion process when the free piston is disposed apart from the valve seat.

Abstract: To minimize an increase in friction during the compression stroke, a part of the force to compress the air in the main combustion chamber is stored as a spring force to prevent an excess rise of compressed air pressure in the main combustion chamber and to keep low the pressure difference between the main combustion chamber and the pre-combustion chamber. The spring force stored in the spring is recovered as a work during the power stroke to reduce the energy that is used in the form of friction and heat, thereby improving the utilization of air in the main combustion chamber, increasing the combustion speed in the main combustion chamber, shortening the combustion period. By applying the spring force stored in the spring to the piston as a work, the fuel cost is reduced.

Abstract: A sub-piston 19 is supported movably in the upward and downward direction on an upper end of a main piston 4 to define an air-fuel mixture cooling chamber 20 between the pistons 4 and 19. The air-fuel mixture cooling chamber 20 communicates with a peripheral edge of a combustion chamber 12. The sub-piston 19 is connected to a cam member 23 which is supported on a crankshaft 7 through a subsidiary connecting rod 21. The volume of the air-fuel mixture cooling chamber 20 is increased and decreased in operative association with the rotation of the crankshaft 7. The air-fuel mixture cooling chamber 20 has an increased volume in a phase from a compression stroke to a point immediately after ignition, and the generation of a knocking is prevented by cooling an air-fuel mixture filled in such air-fuel mixture cooling chamber 20.

Abstract: The two-cycle engine is constructed with a flywheel having pockets spaced about the periphery. The flywheel receives charges of combusted media at spaced apart points so as to rotate the flywheel. Each piston/cylinder arrangement for delivering power to the flywheel cooperates with a spring-biased counter-piston whereby after ignition, the counter-piston moves away from an associated piston to permit exhausting of the combusted mixture into a pocket of the rotating flywheel. The spring stores the energy caused by combustion and delivers the energy into the flywheel during exhaustion of the combusted mixture.

Abstract: A supplemental cylinder head assembly for operation of an engine in a homogeneous charge compression ignition combustion mode. The supplemental cylinder head assembly provides a movable accumulator piston position above the main combustion chamber. The accumulator piston is upwardly responsive to the combustion event in the main combustion chamber and downwardly to a preload force. An engine adapted to receive the supplemental cylinder head assembly is capable of efficiently operating on any fuel in the octane range of zero to 130.

Abstract: An internal combustion engine having at least one volume adjustable cylinder which automatically adjusts its compression ratio during operation. The volume adjustable cylinder includes a movable head insert placed inside the insert space formed on the engine head directly over the piston. An adjustable lock nut is used to attach the head insert to the engine head and to initially set the position of the head insert in the insert space to establish the initial volume of the combustion chamber of the cylinder. An O-ring made of elastomeric material is disposed between the head insert and the inside surface of the engine head which resists movment of the head insert in the insert space. When the engine operates at higher RPMs, the compression pressure increases inside the cylinder which forces the head insert into the insert space to expand the volume of the combustion chamber which, in turn, reduces the combustion pressure of the cylinder.

Abstract: An internal combustion engine and method for operating the same wherein the combustion chamber volume can be varied depending on throttle position by a member that is inserted into the combustion chamber, and wherein the intake valve is closed before the piston completes its intake stroke so that the expansion stroke is effectively lengthened. In the case of a two-stroke engine, some of the intake gas is expelled before combustion to achieve an effective lengthening of the expansion stroke.

Abstract: The invention is directed towards adjusting the combustion ratio of an internal combustion engine. The apparatus has a compensator piston which is selectively hydraulically positioned. The piston is linked to a shock adsorber so as to keep the combustion chamber charge from reaching the pressure detonation limit.

Abstract: A variable compression ratio internal combustion engine having at least one cylinder, a piston disposed in the cylinder and a cylinder head disposed at one end of the cylinder. The cylinder head has a combustion chamber and a piston chamber contiguous with the top of the cylinder. A movable piston disposed in the piston chamber to change the effective volume of the combustion chamber. A closed end of the piston chamber is connected to one of the engine's source of pressurized fluid. A solenoid valve is disposed between the source of pressurized fluid and the piston chamber. Energization of the solenoid valve is controlled by a controller to open the solenoid valve when the combustion chamber has a low pressure to displace the movable piston to increase the compression ratio of the engine and to open the solenoid valve when the combustion chamber has a high or peak pressure to displace the movable piston to decrease the compression ratio.

Abstract: An optimized unitary energetic system for an internal combustion engine comprising a gas distribution system for intake and exhaust associated with an optimized variable geometry combustion chamber with a regenerative cylinder wall lining to contain thermal energy and a microprocessor to correlate certain factors and control the gas distribution system and combustion chamber geometry for optimization of engine operation.

Abstract: A variable compression system for internal combustion engines whose compression ratio is varied by hydraulic regulation of back and forth movement of a sub-piston slidably mounted within a sub-cylinder communicated with a combustion chamber, comprising a control valve for controlling pressure oil supply to a pressure oil chamber formed on a back face of the sub-piston and communicated, via passages, with a spill port for pressure oil release which is formed in a hollow, reciprocative member cooperatively connected to the sub-piston and relatively movably mounting a spilling regulation member thereon.

Abstract: A cam operated internal combustion engine of piston type positive displacement variety, having novel piston-to-cam connecting means. The pistons are cam operated to optimize the aspiration, combustion and expansion process. Executed in axial and radial cam versions, with alternatively a two cycle, four cycle or novel three cycle mode of operation. The arrangements provide advantages in manufacturing and construction, as well as improved thermal efficiencies.

Abstract: An improved engine comprises a primary piston and primary cylinder in which air and fuel is precombusted. The piston is reciprocated in the cylinder by an external prime mover. The exhaust of the precombusted air/fuel mixture is controlled by a floating exhaust valve piston which seats against the exhaust port and has its other end pressurized at a set pressure preferably by an inert gas. The precombusted air/fuel mixtures are exhausted to secondary combustion chambers where additional air, fuel and prime mover exhaust gases are added to increase the velocity and pressure of the gas and provide for more complete combustion of the fuel.

Abstract: The clearance volume of a combustion chamber of an internal combustion engine at the same crankangle is varied by changing the location of a small piston reciprocally disposed in a small cylinder formed in a cylinder head, which small cylinder communicates with an engine cylinder. Changing the location of the small piston is controllable through a link mechanism in response to the movement of a throttle valve for controlling the amount of intake air supplied to the combustion chamber.

Abstract: An engine capable of storing high pressure gases and discharging them to increase the pressure of compressed fuel-mixture. A gas storage chamber is provided adjacent to the combustion chamber. The chamber opens to release high pressure gases just prior to ignition and closes just after ignition to store ignited gases until just prior to the next ignition. The working efficiency of an engine goes up as its compression ratio increases.

Abstract: The engine comprises, for each of its cylinders, an auxiliary piston provided with a piston rod. The piston is movable in a cavity which is formed in the cylinder head and opens into the combustion chamber. The cavity defines with the auxiliary piston an annular chamber around the piston rod. A liquid under pressure is supplied to the annular chamber by way of a check-valve. The rod has an axial bore in which is slidable a slide valve member whose position is under the control of a parameter representing the conditions of operation of the engine. The slide valve member cooperates with at least one escape port formed across the hollow rod to constitute a liquid discharge path for the annular chamber.