Fan blade

Abstract

A fan blade which makes use of the difference in the thermal expansion coefficient to enable the angle of attack to be variable without a substantial change in the camber quantity and without the need to employ a temperature-sensitive fan clutch. The blade is provided with two plate-like members having a smaller thermal expansion coefficient than that of the blade in such a manner that one of the plate-like members is provided on the suction-side surface of the blade so as to extend from the forward edge portion at the distal end of the blade toward the rearward edge portion at the proximal end of the blade, and the other plate-like member is provided on the delivery-side surface of the blade so as to extend from the rearward edge portion at the distal end of the blade toward the forward edge portion at the proximal end of the blade, that is, the two plate-like members provided on the obverse and reverse surface, respectively, of the blade cross each other in a substantially X-shape. Accordingly, the angle of attack of the blade is made variable in accordance with a change in temperature of the air delivered by the fan. The blade may be made of a resin material, while the plate-like members may be made of a metal.

Dependencies are inferred from the claim text.