Abstract: A high-efficiency explosion engine has a double-acting central piston mounted on a shaft within a cylinder to form two combustion chambers. Auxilliary pistons mounted on the ends of the shaft control the intake of gases to the combustion chambers. In one embodiment, the auxilliary pistons are mounted axially offset from the piston shaft. In a further embodiment, fuel is provided through the piston shaft into the combustion chambers dependant upon the position of the piston within the cylinder.

Abstract: The present invention refers to a double-acting, single-cylinder, explosion engine whose peculiarity is to be provided with auxiliary components which permit to optimize the inlet stroke because such auxiliary components are arranged in a way that the gases to be burnt are not inlet by the piston. Such gases are inlet by the auxiliary components.In general the present engine (1) comprises a cylinder (2) in which a piston (3) may run. The median axis of the piston (3) is interested by a through-shaft which is fixed and coaxial to the piston itself. The shaft is divided in two half-shafts (4, 5) having the same size and shape by the piston.The half-shafts (4, 5) comprise pistons (14, 15) which may run in inlet chambers (10, 11) and narrowings (12, 13) or holes, openings, leaks or the like through which the inlet gas passes to reach the respective explosion chambers through heads (8, 9). The cylinder (2) is provided with exhausts (21) at its median part.