Patent ID: 7390169

Claim:
A wind turbine rotor including a rotor hub ( 3 ) and a plurality of blades ( 4 ), and where each blade root ( 16 ) is connected to said rotor hub through a pitch bearing ( 5 ) in such a manner that the pitch angle of the blade is adjustable by a turning of the blade about its longitudinal axis relative to the rotor hub, and where the blade is provided with at least one electrically conducting lightening down-conductor ( 6 ) extending in the longitudinal direction of the blade to the blade root and being electrically isolated from the pitch bearing ( 5 ), and where a spark gap ( 15 ) is provided between the lightning down-conductor and the rotor hub, said spark gap ( 15 ) being adapted to conduct a lightning current passing through the lightning down-conductor to the rotor hub, characterised in that a sliding contact connection ( 7 , 12 ) is provided parallel to the spark gap ( 15 ) between the lightning down-conductor ( 6 ) and the rotor hub ( 3 ), said sliding contact connection ensuring electrical contact between said lightening down-conductor ( 6 ) and said rotor hub ( 3 ) irrespective of the pitch angle of the blade.