Two-stroke internal combustion engine

Claim 1

A two-stroke internal combustion engine, comprising a cylinder having a pair of combustion chambers, a symmetrical, free floating differential piston freely movable within the cylinder, and having two spaced main piston portions each movable in a respective combustion chamber, the combustion chambers being arranged axially inwardly of the respective piston portions and each having exhaust means, an axially extending piston rod connecting said main piston portions, a pre-compression chamber arranged between said combustion chambers, a central, double-acting piston portion on said piston rod movable in said pre-compression chamber and dividing the same into two separate compression chambers, channels of hollow cylindrical configuration connecting the pre-compression chamber with each combustion chamber, said channels being located about said piston rod, and piston type valve means formed on said piston rod for closing the channel leading from one compression chamber to one combustion chamber and for opening the channel leading to the other combustion chamber when its main piston portion is in its bottom dead center position, whereby upon expansion occurring in said one combustion chamber material exchange occurs in the other, and a fuel mixture inlet port communicating with said pre-compression chamber, said double-acting piston portion adapted to close said inlet port and to alternately allow fuel mixture inlet into the separate compression chambers.