SCREW PUMP Russian patent published in 2001 - IPC

FIELD: mechanical engineering; pumps. SUBSTANCE: proposed screw pump has housing, holder, screw-cut rotors, synchronizing gears, working chamber with suction and discharge spacers, inner space with bearing supports, one sealing device in support of driving rotor at side of power drive and flexible envelope secured on flanges at end faces of housing to form working chamber between outer surface of envelope and surface of holder. Working chamber is isolated by envelope form inner space provided with connector for delivery of compressed air to force envelope form surface of screw-cut profile. Screw cut has smooth profile limiting deformation of envelope within working limits, and system of holes and grooves for delivery of auxiliary material, for instance, lubricant, to reduce friction losses between profile and envelope or to prevent contact of profile and envelope. Invention provides reduction of volumetric losses at operation of pump, improves efficiency of pump handling gas-liquid mixtures, reduces number of working turns of screw cut and makes it possible to dispense with end seals. EFFECT: reduced overall dimensions of pump, provision of pump control by delivery and pressure, increased tolerable temperature of handle medium. 2 dwg