| 摘要 |
<p>A pitch change system (30) for varying the pitch of the blades (16) of a multibladed propulsor (10) comprises a pitch change actuation assembly (40) and a pitch change drive assembly (70) for selectively actuating the pitch change actuation assembly (40) whenever it is desired to change blade pitch. The pitch change actuation assembly (40) comprises a ballscrew (42), a ballscrew nut (44) threadably mounted to the ballscrew (42), and a pitch stop assembly (100) having a retractable feather stop (135) which in its normal position prevents the ballscrew (42) from driving the ballscrew nut (44) to move the blades (16) beyond the coarse pitch setting corresponding to blade feather, but in its retracted position permits the ballscrew (42) to drive the ballscrew nut (44) to move the blades (16) through feather to a desired reverse pitch setting.</p> |
