Impeller blade for centrifugal fan and manufacturing method thereof

Abstract

A fan blade made of a solid extruded aluminum alloy having certain cross-section shapes. Also provided is a method of producing fan blade, which includes heating a portion of a stock aluminum alloy material and pushing it through an extrusion die having an aperture while drawing the extruded portion of the material. The aperture can be designed or configured so that the extruded material has a cross section suitable to be used as an impeller blade.

1 . A fan blade made of an extruded aluminum alloy, the fan blade having a width direction and a uniform and solid cross section perpendicular to the width direction, the cross-section having two major opposing sides, a first lateral end, and a second lateral end, the two opposing sides being both smooth curves generally, the two opposing sides defining a thickness therebetween. 
     
     
         2 . The fan blade of  claim 1 , wherein the two major opposing sides curving to opposing directions. 
     
     
         3 . The fan blade of  claim 1 , wherein the two major opposing sides curving to a same direction, and wherein the thickness gradually increases from the first lateral end to the second lateral end. 
     
     
         4 . The fan blade of  claim 3 , wherein the first end has a radius of about 1 mm. 
     
     
         5 . The fan blade of  claim 3 , wherein the second end has an elliptical shape. 
     
     
         6 . The fan blade of  claim 5 , wherein the second end has a thickness of between about 3 mm to about 8 mm. 
     
     
         7 . A centrifugal fan assembly comprising:
 at least one mounting disc having a center and a radius; and   a plurality of fan blades each defined according to  claim 3  mounted on the at least one mounting disc.   
     
     
         8 . The centrifugal fan assembly of  claim 7 , wherein the plurality of fan blades are arranged radially symmetrically with respect to the center of the at least one mounting disc. 
     
     
         9 . The centrifugal fan assembly of  claim 8 , wherein each of the plurality of fan blades are arranged with the first end positioned proximal to the center of the at least one mounting disc and the second end positioned distal to the center of the at least one mounting disc, and wherein the two major opposing sides of all of the plurality of fan blades are curving to the same rotational direction. 
     
     
         10 . The centrifugal fan assembly of  claim 9 , further comprising an electrical motor operatively coupled with the at least one mounting disc, the electrical motor configured to rotate in a direction such that each of the plurality of fan blades are forward-curved. 
     
     
         11 . A method for producing an extruded material, comprising:
 positioning a stock of a metal alloy material such that a first end of the metal alloy material is proximate an extrusion die, the extrusion die having an aperture on an end face;   heating at least a portion of the stock of the metal alloy material proximate the die to soften the portion of the metal alloy material;   pushing the soften portion of the stock of the metal alloy material through aperture along a forward direction such that a portion of the metal alloy material is extruded out of the aperture; and   drawing the portion of the metal alloy material that has been extruded out of the aperture along the forward direction, thereby producing an extruded metal alloy material having a cross section having substantially the shape of the aperture of the extrusion die.   
     
     
         12 . The method of  claim 11 , wherein the metal alloy material comprises aluminum alloy. 
     
     
         13 . The method of  claim 11 , further comprising cutting the extruded material into a plurality of pieces along a direction perpendicular to the forward direction of the extrusion. 
     
     
         14 . The method of  claim 11 , wherein the aperture has a cross-section shape comprising two major opposing sides defining a thickness therebetween, the two major opposing sides both curving in the same direction, wherein one of the sides has a length greater than the other of the sides. 
     
     
         15 . The method of  claim 14 , wherein the thickness gradually increases from the first lateral end to the second lateral end. 
     
     
         16 . The method of  claim 11 , wherein the aperture has a shape comprising two major opposing sides curving in opposite directions. 
     
     
         17 . An extruded metal alloy material or aluminum alloy material made by the method of  claim 11 .