SELF-PRESSURE-REGULATING COMPRESSED AIR ENGINE COMPRISING AN INTEGRATED ACTIVE CHAMBER

The invention relates to a multimode engine comprising an included active chamber, having c cylinder (1) and piston (2) that divides the cylinder into an active chamber (CA) and an expansion chamber (CD), and in which: compressed air contained in a tank (12) directly feeds the intake of the engine cylinder (1), the included active chamber (CA) is filled at a constant admission pressure in the tank decreases, the volume of the included active chamber (CA) increases progressively as the pressure in the tank (12) decreases, means enable not only the admission opening and conduit (7) to be opened essentially at the top dead centre of the stroke of the piston, but also the modification of the duration and/or the angular sector of the admission, in addition to the opening passage section, and the volume of the included active chamber (CA) is dimensioned for maximum storage pressure, and is then progressively increased, resulting in a self-pressure regulating engine.