Abstract: A pitch system (20) for rotating a blade (4) of a wind turbine relative to a hub (6) generally comprises a bearing (22) having an inner bearing ring (30) configured to be mounted to the hub and an outer bearing ring (32) configured to be mounted to the blade. A first coupling member (24) positioned between the hub and inner bearing ring extends radially inward. A second coupling member (26) positioned between the blade and outer bearing ring extends radially inward and over the inner bearing ring. A drive system (28) includes a first drive member (34) coupled to the first coupling member and a first driven member (36) coupled to the second coupling member. The first drive member is configured to move the first driven member to rotate the outer bearing ring relative to the inner bearing ring and thereby pitch the blade.

Abstract: The invention provides a hub for a wind turbine, the hub comprising a continuous shell being assembled from at least two shell parts. To improve stiffness of the hub, a plate element is attached within blade flanges of the assembled hub. Due to the combination between shell parts and a plate element, manufacturing and transportation is facilitated while strength and rigidity is ensured.