FIELD: mechanical engineering. SUBSTANCE: engine has housing 1 with ring working chamber 2 and vane working members. Major working member 3 is rigidly connected with the housing. Auxiliary working member 4 is connected with shaft 5 for periodic changing in the rotation speed and kinematically connected with the flywheel through the crank transmission. The length of the connecting rod and distance between the axle for securing the connecting rod to the auxiliary vane working member and center of the shaft for periodical changing in the rotation speed is greater than the crank length by a factor of 1.2. The distance between the center of rotation of the crank and center of the shaft for periodical changing in the rotation speed is greater than the length of the crank by a factor of 1.2. EFFECT: enhanced efficiency. 2 dwg
