Abstract: A wind turbine rotor includes a hub, a plurality of blades, and a pitch system for rotating a blade substantially along its longitudinal axis. The pitch system includes a bearing, a motor, and a gear system, wherein the gear system has a driving pinion operationally connected with the motor, an annular gear arranged to mesh with the driving pinion. Additional gear teeth are arranged to mesh with other parts of the gear system in a predefined blade position for wind speeds at or below a nominal wind speed such that upon movement from the predefined blade position, the additional gear teeth come into contact with the other parts of the gear system before the driving pinion comes into contact with the annular gear.

Abstract: Wind turbine rotor comprising a hub, a plurality of blades, at least one pitch system for rotating a blade substantially along its longitudinal axis and at least one pitch retention system, wherein a pitch retention system comprises a cam profile and a cam follower, and one of the hub and a blade comprises said cam profile and the other of the hub and blade comprises said cam follower, and wherein the cam follower comprises a pushing member and a contact member, wherein the pushing member is arranged to push the contact member towards the cam profile, and the cam profile comprises a local depression, and wherein the cam follower and cam profile are arranged such that when the blade is in a pitch position at or below nominal wind speed, the contact member can be retained in said local depression.

Abstract: Wind turbine rotor comprising a hub, a plurality of blades and at least one pitch system for rotating a blade substantially along its longitudinal axis, the pitch system comprising a bearing, a motor and a gear system, said gear system comprising a driving pinion operationally connected with the motor, an annular gear arranged to mesh with the driving pinion, and additional gear teeth, the additional gear teeth being arranged to mesh with other parts of the gear system at least in a predefined blade position for wind speeds at or below nominal wind speed, and arranged such that upon movement from said predefined blade position, the additional gear teeth come into contact with said other parts of the gear system before the driving pinion comes into contact with the annular gear.

Abstract: Wind turbine rotor comprising a hub, a plurality of blades, at least one pitch system for rotating a blade substantially along its longitudinal axis and at least one pitch retention system, wherein a pitch retention system comprises a cam profile and a cam follower, and one of the hub and a blade comprises said cam profile and the other of the hub and blade comprises said cam follower, and wherein the cam follower comprises a pushing member and a contact member, wherein the pushing member is arranged to push the contact member towards the cam profile, and the cam profile comprises a local depression, and wherein the cam follower and cam profile are arranged such that when the blade is in a pitch position at or below nominal wind speed, the contact member can be retained in said local depression.