CALCULATION AND PRECISION PROCESSING OF CARDIOCLE AND EXPANDED CARDIOID CASING CURVED SURFACES FOR ECCENTRIC ROTOR VANE PUMPS

摘要

The invention is the derivation of the exact mathematical expressions for the curvature, either cardiocle or expanded cardioid, of the casing of the springless eccentric rotor vane pump, thereby facilitating the precision manufacture of the curved surfaces of the casing using CNC techniques. As a result, the capacity and accuracy of the eccentric rotor vane pump is greatly improved. As the section manufacture and assembly of the casing becomes possible, the mass production of large-sized pumps of 1-meter or larger diameter is now attainable, hitherto regarded as almost impossible, and naturally production cost is also reduced. The unique design which positions the axis of eccentricity in the lower central part or the axis of rotor rotation vertically results in increase in the rotation speed of the rotor, and leads to reduction of friction between the vane ends and the curved surface of the casing as the weight of the vane does not effect the movement of the rotor.