Wind-driven electric generator apparatus of the downwind type with flexible changeable-pitch blades

Wind-driven electric generator apparatus of the downwind type, comprising a turbine head supported for wind-driven yaw movement, the turbine head having rotor blades at one end and having a nacelle cover extending from said one end at one side of an axis of said yaw movement, to an opposite end at an opposite side of said yaw axis, said nacelle cover having openings at its ends and defining an airflow path between and through said openings, said blades having a pitch-changing mechanism for changing the pitch of the blades, said mechanism including an airflow responsive device inside said nacelle cover for changing the pitch of said blades depending on predetermined airflow conditions.

Wind-driven electric generator apparatus of the downwind type, comprising a turbine head supported for yaw movement, the turbine head including a drive shaft supported for rotation about an axis transverse to an axis of the yaw movement, the drive shaft having a hub thereon and blades attached to the hub by a mechanism that permits the blades to change pitch, and a blade pitch changing mechanism that comprises a pitch beam having a first portion extending longitudinally of the drive shaft and a second portion extending transversely of the drive shaft and connected to the blades by respective pitch linkages, each pitch linkage including a tie-rod, one end of which is connected to the second portion of the pitch beam by a single-degree-of-freedom pivot and an opposite end of which is connected to a blade by a ball joint, whereby the pitch beam rotates with the drive shaft, and wherein the pitch-changing mechanism moves the first portion of the pitch beam along the drive shaft to change the pitch of the blades.

Wind-driven electric generator apparatus of the downwind type, comprising a turbine head supported for yaw movement, the turbine head including a drive shaft supported for rotation about an axis transverse to an axis of the yaw movement, the drive shaft having a hub thereon with flexible blades, each blade being connected to the hub by a mechanism that comprises a pitch pivot including a stub shaft extending slidably into a ball joint, whereby the pitch of the blades can be changed and the blades can cone.

Wind-driven electric generator apparatus of the downwind type, comprising a turbine head supported for yaw movement, the turbine head including a drive shaft supported for rotation about an axis transverse to an axis of the yaw movement, the drive shaft having a hub thereon and blades attached to the hub by a mechanism that permits the blades to change pitch, and a blade pitch-changing mechanism connected to the blades, wherein the turbine head has a cover with end portions having openings for airflow through the turbine head, and wherein the pitch-changing mechanism includes a device inside the cover that is responsive to airflow therein and that controls the pitch-changing mechanism to pitch the blades to a stall position in the absence of predetermined airflow conditions.