| abstract |
A rotary pump for pumping fluid through a patient comprises:n (a) a housing (324) (b) a stator member (320) attached to said housing (324) andnhaving a first portion, a second portion, and anplurality of stationary blades (334) attached to saidnstator member (320) at said first portion thereof,nwherein said stator member is generally axiallynsymmetric having a substantially conical-shaped tail andna substantially conical-shaped nose; (c) an impeller (322) positioned within said housing andnhaving an exterior wall, an interior wall forming anvoid, a plurality of outboard blades (360) extendingnoutwardly from said exterior wall, and a plurality ofninboard blades (372) extending inwardly from saidninterior wall, wherein said stator member second portionnextends within said interior wall of said impeller, andnwherein said inboard impeller blades (372) are concavenor convex (longitudinal curve) such that the curvaturenthereof corresponds with the curvature of said statornmember (320); (d) means for levitating said impeller (322) which centresnsaid impeller within said housing (324); and (e) means for rotating said impeller (322) which exerts andnforce on said plurality of impeller blades (372) tonrotate said impeller. n The impeller preferably has an ellipsoidal configuration. |