Patent ID: 7490460
Filing Date: 2009-02-17
Classification: F02C,F02K,F05D,F16H,Y02T

Abstract:
1. A method for assembling a gas turbine engine, said method comprising: providing a core gas turbine engine at least partially defined by a frame and having a drive shaft rotatable about a longitudinal axis of the core gas turbine engine; coupling a low-pressure turbine to the core gas turbine engine; coupling a counter-rotating fan assembly including a first fan assembly and a second fan assembly to the low-pressure turbine such that the first fan assembly rotates in a first direction and the second fan assembly rotates in an opposite second direction; coupling a gearbox between the shaft and the counter-rotating fan assembly so that the gear box extends substantially circumferentially about the drive shaft, the gearbox including a support structure including a first portion and a second portion; coupling a gearbox input to the low-pressure turbine; coupling a gearbox output to the counter-rotating fan assembly; and coupling a thrust spring between the gearbox input and the gearbox output to at least partially absorb the thrust generated by the counter-rotating fan assembly the thrust spring formed unitarily with the first and second portions, a plurality of openings formed through the thrust spring to facilitate adjusting the thrust absorbed by the thrust spring.