FIELD: mechanical engineering; transport vehicles. SUBSTANCE: invention relates to internal combustion engines of power plants in which liter capacity it of vital importance. Proposed method includes suction of fresh fuel air mixture into crank chamber and compression of mixture, bypassing of prepared fuel air mixture into working chamber of cylinder, compression and ignition of mixture, expansion of gases formed at combustion which make piston move, opening of exhaust ports and discharge of exhaust gases into atmosphere, opening of scavenging ports and scavenging of cylinder working space, and delivery of fresh portion of charge into cylinder working space. Beginning and end of crank chamber filling phase is set by angular forming to shape of slots in cheeks-balances of engine crankshaft. Mixing and compressing of fresh fuel-air mixture is carried out in rotating crank chamber in which position of front and rear sharp edges playing the part of spool is set on outer circumference of formed-to-shaped cheeks-balances by angular coordinates equal to θf = 25-50° from bottom dead center for front edge and θr = 0-95° from top dead center for rear edge. Said method is provided in internal combustion engine containing one or more working cylinders with liners, pistons mechanically connected through connecting rods and cranks with cheeks-balances of crankshaft and spool devices. Cylinder liners have scavenging and exhaust ports and cheeks-balances of crankshaft have slots pneumatically coupled with intake and bypass branch pipes. Ratio of volume of rotating crank chambers formed by formed-to-shape slots of crankshaft cheeks-balances and formed-to-shape bypass branch pipes to full volume of each crank chamber is from Vrot = 30% to Vrot = 50%. EFFECT: improved performance characteristics of two-stroke internal combustion engine by perfecting gas exchange process and transfer to asymmetrical phases of valve actuating. 13 cl, 7 dwg
