FIELD: mechanical engineering. SUBSTANCE: invention relates to air supply systems of free piston engines. According to said method of scavenging of free piston engine through engine piston valves, direction of scavenging is changed periodically to opposite one. Said device consists of pistons with valves, intake and outlet manifolds and scavenging set with compression and gas ports. Intake and outlet manifolds are combined into common system which is connected with compression and gas ports of scavenging set through gas and scavenging guide which periodically changes direction of scavenging air into opposite one. EFFECT: reduced heat stresses of pistons and improved reliability of engine. 3 cl, 1 dwg
