Patent ID: 7419359

Claim:
An axial flow impeller ( 1 ), rotationally driven by a motor ( 3 a ) about an axis ( 2 ) in a direction (V) in a plane (XY), comprising a central hub ( 3 ) of diameter (D 1 ), a plurality of blades ( 4 ), each blade having a base ( 5 ) with a theoretical starting radius (Rmin), and a tip ( 6 ) that extends to an end radius (Rmax), the blades ( 4 ) being delimited by a concave leading edge ( 7 ) and a convex trailing edge ( 8 ), characterised in that the blades ( 4 ) include box-shaped portions ( 20 ) that define a seat ( 21 ) with a diameter (D 2 ) greater than the diameter (D 1 ) of the housing of the electric motor ( 3 a ).