Reinforced fan blade construction

Abstract

There is provided herein a reinforced fan blade construction which is reinforced at a proximal end thereof utilising a pair of opposing reinforcement brackets, typically metallic. In this way, the fan blade member may be manufactured from Acrylonitrile butadiene styrene (ABS) plastic or the like which is typically cheaper, lighter and easier to colour as opposed to other fan blade materials. Furthermore, plastic is noncorrosive allowing for outdoor application. The reinforcement brackets may comprise an elongate stem and an orthogonal cross piece. The orthogonal cross piece (which may be semicircular) may attached directly to the drive motor annulus such that inertial strain imparted thereon is spread along the elongate stem thereby reinforcing the proximal end of the fan blade.

1 . A reinforced fan blade construction comprising:
 an elongate fan blade member defining a distal end and an opposite proximal attachment end; and   upper and lower reinforcing brackets engaged oppositely through the proximal end for reinforcement.   
     
     
         2 . A reinforced fan blade construction as claimed in  claim 2 , wherein the reinforcement brackets are planar. 
     
     
         3 . A reinforced fan blade construction as claimed in  claim 2 , wherein the proximal end is shaped to define a planar engagement piece against which the respective upper and lower planar reinforcement brackets lie flush. 
     
     
         4 . A reinforced fan blade construction as claimed in  claim 3 , wherein the planar engagement piece and the reinforcing brackets define corresponding rivet accommodation apertures and wherein the brackets are riveted to the planar engagement piece. 
     
     
         5 . A reinforced fan blade construction as claimed in  claim 2 , wherein each reinforcement bracket comprises an elongate stem and a cross piece. 
     
     
         6 . A reinforced fan blade construction as claimed in  claim 5 , wherein the elongate stem defines a plurality of rivet attachment apertures. 
     
     
         7 . A reinforced fan blade construction as claimed in  claim 5 , wherein the cross piece defines a plurality of attachment fastener apertures. 
     
     
         8 . A reinforced fan blade construction as claimed in  claim 8 , wherein the cross piece is semicircular. 
     
     
         9 . A reinforced fan blade construction as claimed in  claim 3 , wherein the upper surface of the proximal end defines a predominance and a corresponding undersurface of the proximal end defines a recess and wherein the upper enforcement brackets locates on or within the predominance and the lower reinforcement bracket locates within the recess. 
     
     
         10 . A reinforced fan blade construction as claimed in  claim 9 , further comprising an under covering for covering the recess. 
     
     
         11 . A reinforced fan blade construction as claimed in  claim 10 , wherein the under covering comprises a cross-section conforming to that of the recess. 
     
     
         12 . A reinforced fan blade construction as claimed in  claim 10 , wherein the under covering is configured to lie flush when in the recess. 
     
     
         13 . A reinforced fan blade construction as claimed in  claim 12 , wherein the covering comprises proximal fastener attachment apertures. 
     
     
         14 . A reinforced fan blade construction as claimed in  claim 13 , wherein the covering defines a distal end and wherein the distal end is devoid of fastener apertures. 
     
     
         15 . A reinforced fan blade construction as claimed in  claim 12 , wherein an upper surface of the distal end comprises a centreboard comprising a linear edge for abutting against a corresponding undersurface of the adjacent lower attachment bracket. 
     
     
         16 . A reinforced fan blade construction as claimed in  claim 2 , wherein the proximal end further defines a prow, the prow supporting the planar engagement piece therein and comprising lateral edges which fall away to the predominance. 
     
     
         17 . A reinforced fan blade construction as claimed in  claim 18 , wherein the prow extends into a trailing edge pitch transition. 
     
     
         18 . A reinforced fan blade construction as claimed in  claim 9 , wherein the recess comprises a cross-section conforming to that of the reinforcement bracket. 
     
     
         19 . A reinforced fan blade construction as claimed in  claim 18 , wherein the covering comprises a cross-section conforming to that of the reinforcement bracket. 
     
     
         20 . A reinforced fan blade construction as claimed in  claim 1 , wherein the fan blade member comprises Acrylonitrile butadiene styrene (ABS) plastic.