Method of fan blade manufacture

Abstract

A blade for a fan is formed by rotomolding around a pre-positioned support member, part of which extends out of the mold, the support member being shaped, or being provided with one or more projections, which are partly embedded in the plastic material forming a skin of the fan blade. The fan blade is made hollow by this method, but is preferably filled either during molding or subsequently with a hard foam material. A hub is also provided for mounting any fan blades, but in particular those made by the method, in which a hub includes a body portion having a first radial face associated therewith, a plate having a second radial face parallel to the first radial face and spaced therefrom, and a plurality of circumferentially equally spaced depressions facing one another on the first and second radial faces to accommodate the fan blade support members, means being provided to secure the plate to the body portion effective to clamp the fan blade and support members firmly.

Dependencies are inferred from the claim text.