Patent ID: 8585367

Claim:
A wind turbine comprising a nacelle and a rotor, said rotor being rotatably mounted on said nacelle by means of at least one main bearing unit characterized in that said main bearing unit comprises at least one outer ring, at least one centre ring being radially positioned inwardly in relation to said outer ring, a first bearing assembly disposed between said outer ring and said centre ring and having an outer race, an inner race, and rolling elements disposed between said outer and inner races, at least one inner ring being radially positioned inwardly in relation to said centre ring, a second bearing assembly disposed between said centre ring and said inner ring and having an outer race, an inner race, and rolling elements disposed between said outer and inner races, and wherein said centre ring is capable of rotation in relation to said outer ring and said inner ring, or said outer ring and said inner ring are capable of rotation in relation to said centre ring, subsequent to assembly of said wind turbine.