Patent ID: 7410442

Claim:
In a wind turbine having a wind-driven rotor and an electrical generator, a transmission located between the rotor and the generator for transferring power between them, said transmission comprising: a housing; a shaft in the housing; a helical gear on the shaft and meshing with another helical gear such that torque applied to the gears imparts a thrust load to the shaft, with the direction of the thrust depending on the direction of rotation, one direction of rotation normally resulting in a greater thrust than the other direction of rotation; a first bearing supporting the shaft in the housing and being capable of transferring radial loads between the shaft and the housing; a second bearing supporting the shaft in the housing and being capable of transferring both radial loads and thrust loads in both axial directions between the shaft and the housing, the second bearing including: a cone located around the shaft and having a tapered raceway presented outwardly away from the shaft; a cup located in the housing and having a tapered raceway presented inwardly toward the raceway on the cone; a small rib at the small end of the tapered raceway on the cone; a large rib at the large end of the tapered raceway on the cup; and tapered rollers located in a single row between the raceways and between the ribs and having their tapered side faces against the raceways and their large and small end faces along the large and small ribs, respectively; whereby thrust loads in one direction are applied to the rollers at the raceways and in the other direction are applied to the rollers at the ribs, the bearing being oriented such that the normally greater thrust loads are applied to the rollers at the raceways.