Fan Hub Stiffener

Abstract

A fan hub stiffener is provided. The stiffener occupies a gap between parallel fan hub plates to reduce or eliminate stress on the plates during operation. The stiffener may include a body and arms extending radially outward from the body and into the spaces between adjacent fan blades.

1 . A fan hub comprising:
 a front plate comprising an inner facing surface and an outer facing surface, the front plate having a diameter and a perimeter;   a rear plate comprising an inner facing surface and an outer facing surface, the rear plate having a diameter and a perimeter, the front plate and the rear plate each defining a central bore, a plurality of sets of blade fastener apertures arranged circumferentially around each plate near the plate perimeter, a plurality of central hub connection fastener apertures arranged circumferentially around the central bore, and a plurality of stiffener fastener apertures, the central bore, the blade fastener apertures, the central hub connection fastener apertures and the stiffener fastener apertures of the rear plate registering with the central bore, the blade fastener apertures, the central hub connection fastener apertures and the stiffener fastener apertures of the front plate;   an annular central hub connection defining an inner bore registering with the central bores of the front plate and the rear plate, the central hub connection having a cylindrical outer wall facing radially outward, the central hub connection further defining central hub connection apertures registering with the central hub connection fastener apertures of the front plate and the rear plate; and   a stiffener comprising a body and a plurality of arms extending radially outward from a perimeter of the body, the body defining a stiffener central bore registering with central bores of the front plate and the rear plate, the stiffener having an outer diameter no larger than the diameter of the front plate, each arm extending radially outward from the body and between adjacent sets of blade fastener apertures, the stiffener defining apertures for receiving fasteners, the stiffener apertures registering with some or all of the stiffener fastener apertures in the front plate and the rear plate.   
     
     
         2 . The fan hub of  claim 1  wherein the stiffener has a mass that is evenly distributed about the central bore. 
     
     
         3 . The fan hub of  claim 1  wherein the stiffener fastener apertures and the stiffener apertures are distributed symmetrically around the plate central bore. 
     
     
         4 . The fan hub of  claim 1  wherein stiffener fastener apertures and the stiffener apertures are arranged in two or more concentric circular arrays centered around the central bore. 
     
     
         5 . The fan hub of  claim 1  wherein 1 the stiffener defines voids oriented symmetrically about the stiffener central bore. 
     
     
         6 . The fan hub of  claim 1  wherein the stiffener abuts the front plate and the rear plate and wherein the stiffener has an annular inner wall that abuts the central hub connection outer wall. 
     
     
         7 . The fan hub of  claim 1  wherein the front plate, the rear plate and the central hub connection define a gap, and the stiffener is located in the gap. 
     
     
         8 . The fan hub of  claim 1  wherein the stiffener is fastened to the front plate and to the rear plate at two or more annular locations about the central hub connection. 
     
     
         9 . The fan hub of  claim 1  wherein the stiffener is fastened to the front plate and to the rear plate at the stiffener body a short distance from the central hub connection and at radially distal ends of the stiffener arms near the perimeter of the front plate and the rear plate. 
     
     
         10 . The fan hub of  claim 1  wherein the stiffener is of unitary construction. 
     
     
         11 . The fan hub of  claim 1  wherein the stiffener comprises multiple stiffener plates having a total axial thickness equal to an axial thickness of the gap between the plates. 
     
     
         12 . A fan comprising:
 a fan hub comprising a front plate, a rear plate and a central hub connection, the front plate comprising an inner facing surface and an outer facing surface, the front plate having a diameter and a perimeter, the rear plate comprising an inner facing surface and an outer facing surface, the rear plate having a diameter and a perimeter, the front plate and the rear plate each defining a central bore, a plurality of sets of blade fastener apertures arranged circumferentially around each plate near the plate perimeter, a plurality of central hub connection fastener apertures arranged circumferentially around the central bore, and a plurality of stiffener fastener apertures, the central bore, the blade fastener apertures, the central hub connection having a cylindrical outer wall facing radially outward and defining central hub connection apertures registering with the central hub connection fastener apertures of the front plate and the rear plate;   a plurality of fan blades affixed to the fan hub, each blade comprising an inner portion located between the front plate and the rear plate; and   a stiffener comprising a body and a plurality of arms extending radially outward from a perimeter of the body, the body defining a stiffener central bore registering with central bores of the front plate and the rear plate, the stiffener having an outer diameter no larger than the diameter of the front plate, each arm extending radially outward from the body and between adjacent sets of blade fastener apertures, the stiffener defining apertures for receiving fasteners, the stiffener apertures registering with some or all of the stiffener fastener apertures in the front plate and the rear plate.   
     
     
         13 . The fan of  claim 12  wherein the stiffener has a mass that is evenly distributed about the stiffener central bore. 
     
     
         14 . The fan of  claim 12  wherein the stiffener abuts the front plate and the rear plate and wherein the stiffener has an annular inner wall that abuts the central hub connection outer wall. 
     
     
         15 . The fan of  claim 12  wherein the front plate, the rear plate, the central hub connection and the blade inner portions define a gap, and the stiffener is located in the gap. 
     
     
         16 . The fan of  claim 12  wherein the stiffener comprises multiple stiffener plates having a total axial thickness equal to an axial thickness of the gap between the plates. 
     
     
         17 . A work machine comprising a cooling system with a fan, the fan comprising:
 a fan hub comprising a front plate, a rear plate and a central hub connection, the front plate comprising an inner facing surface and an outer facing surface, the front plate having a diameter and a perimeter, the rear plate comprising an inner facing surface and an outer facing surface, the rear plate having a diameter and a perimeter, the front plate and the rear plate each defining a central bore, a plurality of sets of blade fastener apertures arranged circumferentially around each plate near the plate perimeter, a plurality of central hub connection fastener apertures arranged circumferentially around the central bore, and a plurality of stiffener fastener apertures, the central bore, the blade fastener apertures, the central hub connection having a cylindrical outer wall facing radially outward and defining central hub connection apertures registering with the central hub connection fastener apertures of the front plate and the rear plate;   a plurality of fan blades affixed to the fan hub, each blade comprising an inner portion located between the front plate and the rear plate; and   a stiffener comprising a body and a plurality of arms extending radially outward from a perimeter of the body, the body defining a stiffener central bore registering with central bores of the front plate and the rear plate, the stiffener having an outer diameter no larger than the diameter of the front plate, each arm extending radially outward from the body and between adjacent sets of blade fastener apertures, the stiffener defining apertures for receiving fasteners, the stiffener apertures registering with some or all of the stiffener fastener apertures in the front plate and the rear plate.   
     
     
         18 . The work machine of  claim 17  wherein the stiffener has a mass that is evenly distributed about the stiffener central bore. 
     
     
         19 . The work machine of  claim 17  wherein the stiffener abuts the front plate and the rear plate and wherein the stiffener has an annular inner wall that abuts the central hub connection outer wall. 
     
     
         20 . The work machine of  claim 17  wherein the work machine is one of a mining truck, an earth moving machine, an on-road truck, an off-road truck, a construction machine, a tractor, and a people hauler.