Patent 7108482 was granted and assigned to Bosch on September, 2006 by the United States Patent and Trademark Office.
The present invention provides a centrifugal fan including a hub adapted for rotation about a central axis and a plurality of blades arranged about the central axis and coupled for rotation with the hub. Each of the blades includes a curvature in a plane that extends through the blade and is tangent to a cylinder which extends through the blade and is centered along the central axis.