| 摘要 |
A fan rotor 12 having a hub 16 and plurality of pitch adjustable blades 20, a fluid operated actuator 40 controlled by an electrical actuator 66. The fan control may utilise a solenoid 66 mounted coaxial with the fan hub 16 with windings 80 fixed against rotation, a tapered or profiled plunger 70 as the electrical actuator arranged to provide a variable force, and receiving a PWM signal modulated by one or more parameters. The fluid operated actuator may be a piston 40 which is spring biased 48, connected to the moveable fan blades 20, using fluid pressure generated from an internal gear pump mounted within the fan hub in an epicyclical relationship having a sun 58 and planet 56 gear. The piston 40 displacement may be linearly dependent on the electrical actuator force. Instead of blade control other arrangements may be used such as a viscous clutch included in the rotor drive train. |
