Electrohydraulic servo-distributor for aircraft braking systems - has primary controller electrically activated and secondary controller operating only when brake pedal is pushed

摘要

The appts. has a first inlet for pressurised fluid, a working outlet, a fluid recovery outlet and an electromagnetically actuated pilot stage to a second fluid inlet. A group of outlets is also provided, with the second inlet being linked to the first inlet by a fluidic conduit. A secondary control stage has a slider in a passage, together defining at least three chambers with the slider moving to interlink in various combinations the outlets of the pilot stage, the recovery outlet, and the working outlet. A spring acts on the slider. A second spring acts on the slider in opposition to the first spring to keep the slider in a preferred location. A linkage exerts a force on the second spring, and hence on the slider. The linkage comprises a displaceable rod, forming the valve of a tap in the first fluid conduit linking primary and secondary stages. The tap is operated by a linkage coupled to the brake pedal in the aircraft cockpit.