FIELD: engine engineering. SUBSTANCE: engine has chambers 1 and 2 of variable volume for providing working process and combustion chamber of a constant volume that are coaxial to chambers 1 and 2 and interposed between them. The chambers are interposed between rotors 3 and 5 that rotate synchronously in one direction. The engine is provided with a facility for by-passing fluid through combustion chambers 7. The facility has disk 14 from the side of the inlet. The disk is provided with three opening and rigidly secured to central shaft 8. Wall 6 of each combustion chamber 7 from the side of the outlet is provided with three passageways 16 that are arranged so that they are overlapped fully with the end faces of rotators 5 when the openings in disk 14 are coincident with openings 29 of the inlet of combustion chamber 7. Rotors 3 and 5 are mounted in pair on shafts 8 and 9 and arranged on both side of combustion chambers 7. Shafts 8 and 9 are set in rolling bearings inside the housing of the engine. A gear transmission that consists of seven driving gears 22, three parasite unit-gears 23, and driven gear 24, synchronizes rotation of rotors 3 and 5 and torque applied to output shaft 25 of the engine. EFFECT: enhanced efficiency. 3 cl, 8 dwg
