Patent attributes
An impeller for an electric fan, has a central hub for connection to the rotor of an electric motor, and from which a plurality of blades extends. The hub is bowl-shaped, with an end wall which is connected to an annular lateral wall, and its end wall has a plurality of slots, spaced apart circumferentially, which are inclined in the same direction with respect to the radial direction. The inner surface of the end wall of the hub has a plurality of ribs protruding from this surface, between the slots, these ribs also being inclined in the same direction with respect to the radial direction and being adapted to serve as inner fan blades. These ribs have at least one substantially transverse cut-out or interruption in a predetermined position.
