Eccentric archimedian screw pump of rotary displacement type

摘要

This disclosure relates to a pump including a stator formed with a spiral pump cavity therethrough, which is generally oval in cross section, and a spiral pump rotor which is generally circular in cross section and extends through the cavity. The rotor has a shaft fixed thereto and the axis of the shaft is eccentrically located from the centerline of the spiral cavity by a distance e, so that the shaft makes a hypocycloidal motion with its axis orbiting in a circle having a radius equal to the distance e. The pump further includes a drum journalled concentrically with the spiral cavity. The shaft is journalled on the drum in parallel with the drum axis but eccentrically therefrom by the distance e.