Turbine engine and load reduction device thereof

Abstract

A fan rotor apparatus includes: a rotatable fan disk defining a central aperture and carrying an array of airfoil-shaped fan blades around its periphery, the disk having a forward end and an aft end; and an annular, generally axially-extending forward fan shaft extending through the aperture and coupled to the fan disk for rotation therewith, where the forward fan shaft joins the fan disk at or near the forward end.

1 . A fan rotor apparatus comprising:
 a rotatable fan disk defining a central aperture and carrying an array of airfoil-shaped fan blades around its periphery, the disk having a forward end and an aft end; and   an annular, generally axially-extending forward fan shaft extending through the aperture and coupled to the fan disk for rotation therewith, where the forward fan shaft joins the fan disk at or near the forward end of the fan disk.   
     
     
         2 . The apparatus of  claim 1  wherein a forward end of the forward fan shaft is disposed axially forward of the forward end of the fan disk. 
     
     
         3 . The apparatus of  claim 1  wherein the fan disk comprises a disk arm extending from the forward end which is coupled to the forward fan shaft. 
     
     
         4 . The apparatus of  claim 3  wherein the disk arm comprises:
 a forward portion having a C-shaped cross-section, and 
 an aft portion extending axially between the forward portion and the forward fan shaft. 
 
     
     
         5 . The apparatus of  claim 4  wherein a least a part of the forward portion of the disk arm is disposed axially forward of the forward end of the fan disk. 
     
     
         6 . The apparatus of  claim 1  wherein the forward fan shaft is integrally-formed with the fan disk. 
     
     
         7 . The apparatus of  claim 1  wherein:
 the forward fan shaft is coupled to a rear fan shaft, the two shafts collectively forming an inner shaft; and 
 the inner shaft is mounted for rotation in a plurality of rolling-element bearings axially spaced apart along the inner shaft. 
 
     
     
         8 . The apparatus of  claim 7  wherein at least one of the bearings is mounted a structural support frame by a fuse which is configured to fail at a predetermined radial load. 
     
     
         9 . A turbofan engine, comprising:
 a turbomachinery core operable to produce a flow of pressurized combustion gases;   a turbine disposed aft of the core;   a rotatable fan disk mounted forward of the core, the fan disk defining a central aperture and carrying an array of airfoil-shaped fan blades around its periphery, the disk having a forward end and an aft end;   an annular, generally axially-extending forward fan shaft mechanically coupled to the turbine, the forward fan shaft extending through the aperture and coupled to the fan disk for rotation therewith, where the forward fan shaft joins the fan disk at or near the forward end of the fan disk.   
     
     
         10 . The engine of  claim 9  wherein a forward end of the forward shaft is disposed axially forward of the forward end of the fan disk. 
     
     
         11 . The engine of  claim 9  wherein the fan disk comprises a disk arm extending from the forward end which is coupled to the forward fan shaft: 
     
     
         12 . The engine of  claim 11  wherein the disk arm comprises:
 a forward portion having a C-shaped cross-section, and 
 an aft portion extending axially between the forward portion and the forward fan shaft. 
 
     
     
         13 . The engine of  claim 12  wherein a least a part of the forward portion of the disk arm is disposed axially forward of the forward end of the fan disk. 
     
     
         14 . The engine of  claim 9  wherein the forward fan shaft is integrally-formed with the fan disk. 
     
     
         15 . The engine of  claim 9  wherein:
 the forward fan shaft is coupled to a rear fan shaft, the two shafts collectively forming an inner shaft which extends between the turbine and the fan disk; and 
 the inner shaft is mounted for rotation in a plurality of rolling-element bearings axially spaced apart along the inner shaft. 
 
     
     
         16 . The engine of  claim 15  wherein at least one of the bearings is mounted a structural support frame by a fuse which is configured to fail at a predetermined radial load.