Patent attributes
A pump assembly that includes a pump housing defining an inlet for receiving fluid to be pumped and an outlet for discharging fluid. A rotatable impeller operatively coupled to a drive motor includes a plurality of vane structures integrally formed with a shroud. Each vane structure includes a curved, axial vane segment extending axially from the shroud. A compound, multi-step auxiliary vane extends transversely from each axial vane segment. The auxiliary vane or wing includes at least first and second sections, with the second section overlying the first section in a staggered configuration such that the trailing edges of the first and second sections are spaced apart to form a step. The second auxiliary vane section includes an axial surface that also forms a working vane surface for the auxiliary vane.