| 摘要 |
<p>BLADE PITCH ACTUATION SYSTEM Blade pitch actuation system wherein the blades are hydraulically maintained in phase with one another. The system comprises hydraulic actuators each adapted to drive a single blade in a pitch change mode of operation. Fluid flow to the actuators is controlled by a blade actuator control valve in fluid communication with the actuators and an hydraulic fluid source and drain. An input member of the control valve is provided with passages which provide selected communication between the hydraulic fluid source and drain and passages in cooperating control valve feedback members each operated by, and in fluid communication with one of the blade actuators. The input and feedback members are positionable along one another such that selective positioning of the input member causes simultaneous selected pressurization and draining of the blade actuators through the feedback members thereby effecting a desired, phased blade pitch setting. The phased movement of the blades to such setting causes a corresponding movement of the feedback members nulling the actuator control valve and preventing deviation in blade pitch from the desired setting.</p> |
