| 摘要 |
<p>A hydraulic system for raising and lowering aircraft landing gear (11, 12) includes an actuator (18) which is extendible and retractable to operate the landing gear, the actuator (18) including a movable member (19) in a casing (20), the movable member (19) being moved relative to the casing (20) in a first direction to extend the actuator (18) when fluid under pressure is supplied to a first side (22) of the movable member (19) whilst fluid is exhausted from a second side (23) of the movable member (19), and the movable member (19) being moved in a second direction to retract the actuator (18) when fluid under pressure is supplied to the second side (23) of the movable member (19) whilst fluid is exhausted from the first side (22) of the movable member (19), and there being selector valve means (25) selectively to supply pressurised fluid to the first (22) or second (23) side of the movable member (19), characterised in that means (40) are provided to permit exhausted fluid from at least one of the first (22) and second (23) sides of the movable member (19) to augment the supplied fluid from the selector valve means (25) and thus be directed with the supplied fluid, to the second (23) or first side (22) respectively of the movable member (19).</p> |
