Bearing for wind turbine

Abstract

A bearing assembly ( 12 ) for a rotating element ( 13 ) has one race ( 15 ) adapted to be fixed relative to ground ( 11 ) and to selectively be free for arcuate movement relative to ground. In a preferred embodiment a selective locking device ( 18 ) is provided for the relatively fixed/movable race ( 15 ).

1 . A bearing assembly for rotatably supporting a rotating element relative to ground and comprising:
 a race adapted to be fixed relative to ground and adapted to be freed relative to ground in arcuate movement;   a mechanism adapted to selectively free the race which is fixed relative to ground for arcuate movement relative to ground; and   an actuator adapted to move the race which is freed relative to ground arcuately.   
     
     
         2 . A bearing assembly according to  claim 1 , wherein the race comprises an inner race, and an outer race concentric with the inner race, one of the inner race or outer race being adapted for fixing against rotation on a ground element. 
     
     
         3 . A bearing assembly according to  claim 2 , further including a locking device adapted to engage one of the inner race or the outer race on demand. 
     
     
         4 . A bearing assembly according to  claim 3 , wherein the locking device is adapted to engage a peripheral surface of one of the inner and outer races. 
     
     
         5 . A bearing assembly according to  claim 4 , wherein the locking device is adapted to engage a circumferential surface of one of the inner and outer races. 
     
     
         6 . A bearing assembly according to  claim 5 , wherein the ground is a shaft and the locking device is an axially movable wedge. 
     
     
         7 . A bearing assembly according to  claim 1 , wherein the actuator comprises a cam ring rotatable about a rotational axis of the bearing assembly. 
     
     
         8 . A bearing assembly according to  claim 1 , wherein the bearing assembly is confined within a tubular envelope defined by an outer diameter of the outer race and an inner diameter of the inner race. 
     
     
         9 . A bearing assembly, comprising:
 an inner race and an outer race, at least one of the inner race and outer race being selectively rotatable or locked against rotation relative to each other or a ground;   a locking device to selectively rotationally lock or unlock at least one of the inner race and outer race relative to each other or ground; and   an actuator to rotate an unlocked race.   
     
     
         10 . A bearing assembly according to  claim 9 , wherein the inner and outer races are concentric. 
     
     
         11 . A bearing assembly according to  claim 10 , wherein the locking device is adapted to engage one of the races on demand. 
     
     
         12 . A bearing assembly according to  claim 11 , wherein the locking device is adapted to engage a peripheral surface of one of the races. 
     
     
         13 . A bearing assembly according to  claim 12 , wherein the locking device is adapted to engage a circumferential surface of one of the races. 
     
     
         14 . A bearing assembly according to  claim 13 , wherein the locking device is an axially movable wedge. 
     
     
         15 . A bearing assembly according to  claim 9 , wherein the actuator comprises a cam ring rotatable about a rotational axis of the bearing assembly. 
     
     
         16 . A bearing assembly according to  claim 9 , wherein the assembly is confined within a tubular envelope defined by an outer diameter of the outer race and an inner diameter of the inner race.