This prototype shows a heat engine with high efficiency which has several characteristics in order to reduce consumption. First and second rate equilibrium and a better durability of the cylinders and pistons are added to these benefits. Its range of application is very wide because of its technical characteristics. 1) It has a big interest in the motor field thanks to its high efficiency and its adaptability to work in the best way in several working conditions. 2) By applying to the static machines, the interest is based on the absence of vibrations, a good efficiency and a small wear of the pistoncylinder-ring. 3) Given the friction between the piston and the cylinder, there is a big interest for the compressor of refrigeration that can use refrigerant without lubricant. In this domain, the possibility of variable compression engine can be used to optimize and regulate these cycles.