AN IMPROVED ROTARY POSITIVE DISPLACEMENT SINGLE SCREW PUMP

摘要

An improved rotary positive displacement single screw pump comprising a sold driving shaft connected to a rotor by means of a parallel shaft universal coupling being adapted to rotate at large angles upto a maximum of 36degrees; the said rotor being tubular to reduce the dead-weight on account of its additional eccentricity and being characterised by a longitudinal single threaded central bore therethrough, so that the cross section at every point is such that the central bore and the outer circumference are truly concentric; the said parallel shaft universal coupling comprising a shaft holder, a central holder and a rotor holder connected in series by means of link members; the said shaft holder having a cylindrical body with a longitudinal threaded bore on its centre and a longitudinal recess on the outer surface thereof a circular plate integral with the body at right angles to its longitudinal axis, the said plate being provided with two lugs protruding in the direction of the said axis of the cylindrical body with holes synchronised with respect to said link members and perpendicular to said axis of cylindrical body; the said central bore and two lugs at each end with synchronised holes perpendicular to the axis of the cylindrical body to each other; the said rotor holder having the same constructional features as the said shaft holder; each said link member being a square or cylindrical element having two skewed through holes.