Fan blade retaining structure

Abstract

A disk 10 includes a plurality of dovetail grooves 12 which are spaced at a predetermined angular interval in a circumferential direction and extend in an axial direction. A fan blade 20 includes a dovetail part 22 which is fitted to each of the dovetail grooves in an axial direction and capable of transmitting a centrifugal force produced during rotation to the disk. The fan blade 20 further includes a projecting part 24 which is positioned in rear of the dovetail part 22 and projects outward more than the dovetail grooves 12 in a circumferential direction. The projecting part 24 is set to be such a size that the projecting part does not interfere with the dovetail groove 12 when the dovetail part 22 is positioned on the inner side of the dovetail groove 12 in a radial direction.

1 . A fan blade retaining structure in which a plurality of fan blades is configured to be attached to an outer periphery of a disk rotationally driven by a turbine,
 wherein the disk includes a plurality of dovetail grooves configured to be spaced at a predetermined angular interval in a circumferential direction and to extend in an axial direction,   wherein each of the fan blades includes a dovetail part configured to be fitted to each of the dovetail grooves in an axial direction and capable of transmitting a centrifugal force produced during rotation to the disk, and a projecting part configured to be positioned in rear of the dovetail part and to project outward more than the dovetail groove in a circumferential direction, and   wherein the projecting part is set to be such a size that the projecting part does not interfere with the dovetail groove when the dovetail part is positioned on the inner side of the dovetail groove in a radial direction.   
   
   
       2 . The fan blade retaining structure according to  claim 1 , further comprising:
 an auxiliary retainer configured to be fixed to the disk and to prevent the fan blade from moving in an axial forward direction.   
   
   
       3 . The fan blade retaining structure according to  claim 1 , wherein the projecting part is formed by cutting, welding or pressure bonding. 
   
   
       4 . The fan blade retaining structure according to  claim 1 , further comprising:
 a fan spacer configured to be inserted between a lower surface of the dovetail part and a bottom surface of the dovetail groove so as to position the dovetail part on the outer side in a radial direction.