ROTARY POSITIVE DISPLACEMENT MACHINE Russian patent published in 2003 - IPC

FIELD: mechanical engineering; pumps and compressors. SUBSTANCE: proposed machine has housing, driving and driven rotors with cylindrical hubs with at least two radial projections with outer cylindrical surface and with side surfaces with concave sections. Each rotor has fixed cylindrical bushing enclosing the shaft and located in inner spaces made in hubs coaxially with shafts. Open parts of spaces are arranged on opposite faces of hubs. Cylindrical longitudinal groove is made on outer surface of each bushing. Grooves are arranged symmetrically with axis connecting centers of rotor rotation. Length of groove arc is smaller than length of arc of mating of radial projections and hubs. Uniform - pitch rectangular slots are made over entire outer convex cylindrical surfaces of bushings. EFFECT: increased efficiency and improved reliability owing to reduction of leaks of working medium. 3 cl, 4 dwg