Patent ID: 6799944
Filing Date: 2004-10-05
Classification: F04D

Abstract:
A rotary pump for pumping of contaminated water including unscreened sewage water, comprising a pump housing (1) provided with a cylindrical inlet (2) and a pump impeller (3) having a central hub (4) and one or several vanes (5) the leading edges (6) of which being swept backwards and located within the inlet part (2) in a plane mainly perpendicular to the axis of rotation (z), one or several feeding grooves (8) being located in the inner wall of the pump housing (1) in a surface (7) opposing the leading edges of the vanes, said grooves being located upstream of the area of said leading edges and are swept from the inlet towards the outlet in the direction of the impeller rotation, characterized in, that at least one means (10) is attached to the pump housing (1) for scraping off pollutants on the leading edges (6) and feeding them towards the periphery within the area of the groove or grooves (8) in the pump housing wall, said means (10) having a plane surface (11) heading and in parallel with the leading edge (6) and located at a distance of 0.05 to 1 mm from said edge.