Patent ID: 7771308

Claim:
A drive assembly for a wind turbine, comprising: a rotor hub; supporting structure; a planetary type gear transmission unit comprising a sun gear, a ring gear with a toothed inner surface, and a planet carrier having a plurality of planet gears arranged thereon, said ring gear being non-rotatably secured to said supporting structure and the planet carrier being co-rotatingly secured to the rotor hub; and a main bearing which rotatably supports the rotor hub relative to said supporting structure, the main bearing having a stationary part being non-rotatably secured to said supporting structure and a co-rotating part secured to the rotor hub; wherein the ring gear is flexibly arranged and connected to a stationary part of the main bearing by means of an intermediate connector part having a first flange secured to the ring gear and a second flange secured to the stationary part of the main bearing, the intermediate connector part being of a flexible structure so as to allow for temporary radial displacements of a toothed inner surface of the ring gear during ordinary operation of the wind turbine so that a shape of the ring gear temporarily deviates from circular while the stationary part of the main bearing is configured to remain stable in shape and the radial forces between the planet gears and the ring gear are substantially equalized between the plurality of planet gears.