Flared tip fan blade and method of manufacturing same

Abstract

A fan blade assembly is provided. The fan blade assembly may include; a fan blade having an airfoil shaped section, formed by being run lengthwise though a die and a flap portion integral with the airfoil section also run lengthwise through the die, the fan blade having a hub end and a tip end, a tapering trailing edge on a trailing edge of the fan blade defined by removing a portion of the trailing edge of the fan blade after it has been run through the die, the tapering trailing edge defining the fan blade to be narrower moving from the hub end toward the tip end, and a flared portion interrupting the tapering trailing edge near the tip end, the flared portion defining the fan blade to become wider from the beginning of the flared portion to the tip end. A method for making a fan blade may also be provided.

1 . A fan blade assembly comprising:
 a fan blade having an airfoil shaped section, formed by being run lengthwise though a die and a flap portion integral with the airfoil section also run lengthwise through the die, the fan blade having a hub end and a tip end;   a tapering trailing edge on a trailing edge of the fan blade defined by removing a portion of the trailing edge of the fan blade after it has been run through the die, the tapering trailing edge defining the fan blade to be narrower moving from the hub end toward the tip end; and   a flared portion interrupting the tapering trailing edge near the tip end, the flared portion defining the fan blade to become wider from the beginning of the flared portion to the tip end.   
     
     
         2 . The fan blade assembly of  claim 1 , wherein the flap portion slopes upward when viewed from the side of the fan blade. 
     
     
         3 . The fan blade assembly of  claim 1 , further comprising plastic insert attached to the fan blade at the tip end. 
     
     
         4 . The fan blade assembly of  claim 3 , wherein the plastic insert is injection molded. 
     
     
         5 . The fan blade assembly of  claim 3 , further comprising rivets connecting the plastic insert to the fan blade. 
     
     
         6 . The fan blade assembly of  claim 1 , further comprising a hub cap located on the hub end of the fan blade. 
     
     
         7 . The fan blade assembly of  claim 1 , further comprising an attaching shank located in an interior of the airfoil portion and configured to attach the fan blade to a hub. 
     
     
         8 . The fan blade assembly of  claim 1 , further comprising a shroud containing the fan blade and a hub. 
     
     
         9 . The fan blade assembly of  claim 1 , further comprising a cooling tower having the fan blade attached to a hub and figured to provide airflow through the cooling tower. 
     
     
         10 . A method of manufacturing a fan blade assembly comprising:
 extruding a metal through a die forming the metal in the shape of fan blade having an airfoil portion and a flap portion;   removing material from the extruded metal on a trailing edge fan blade to be narrower moving from a hub end of the fan blade toward a tip end of the fan blade and shaping the trailing edge of the fan blade to interrupt the tapering trailing edge near the tip end, and forming a flared portion defining the fan blade to become wider from the beginning of the flared portion to the tip end.   
     
     
         11 . The method of  claim 10 , wherein the metal is aluminum. 
     
     
         12 . The method of  claim 10 , further comprising attaching an injection molded plastic cap on the tip end of the blade. 
     
     
         13 . The method of  claim 10 , further wherein the die forms the flap to extend in an upward direction. 
     
     
         14 . The method of  claim 10 , further comprising installing the fan blade in a cooling tower. 
     
     
         15 . The method of  claim 10  further comprising operating a fan comprised of the fan blades. 
     
     
         16 . A method of manufacturing a fan blade assembly comprising:
 pultruding fiberglass wetted with resin through a die forming the fiberglass in the shape of fan blade having an airfoil portion and a flap portion;   removing material from the pultruded fiberglass on a trailing edge fan blade to be narrower moving from a hub end of the fan blade toward a tip end of the fan blade; and   shaping the trailing edge of the fan blade to interrupt the tapering trailing edge near the tip end, and forming a flared portion defining the fan blade to become wider from the beginning of the flared portion to the tip end.   
     
     
         17 . The method of  claim 16 , further comprising attaching an injection molded plastic cap on the tip end of the blade. 
     
     
         18 . The method of  claim 16 , further wherein the die forms the flap to extend in an upward direction. 
     
     
         19 . The method of  claim 16 , further comprising installing the fan blade in a cooling tower. 
     
     
         20 . The method of  claim 16  further comprising operating a fan comprised of the fan blades.