Aircraft Engine-Driven Pumps

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The engine-driven pump (EDP) product line, designed and manufactured by the Parker Aerospace Hydraulic Systems Division (HSD), provides the primary hydraulic power for many of today's leading military and commercial aircraft including:
• Airbus A320, A340, and A350 XWB
• Boeing 737,747, 757, 767, 777, and 787
• Bombardier CRJ 700/900/100, Dash 8/Q-400, Global Express, and Challenger 300
• Cessna Sovereign and Citation X
• Dassault Falcon 7X
• Embraer 170/190
• Lockheed Martin F-16 Fighting Falcon
• Gulfstream G450, G500, G550
• Sukhoi Superjet

Ranging in size from 0.03 to 5.5 in³/rev and capable of operation at system pressures between 1,000 and 8,000 psi, Parker Aerospace EDPs provide unmatched efficiency and reliability in a compact, lightweight package, with a superior power-to-weight ratio.

OPERATION:
EDPs serve as the primary supply of hydraulic flow and pressure for the hydraulic users within the aircraft system. The typical EDP configuration is a pressure-compensated, variable- displacement axial piston pump capable of varying the volume of fluid delivered to maintain hydraulic system pressure.

The rotating group is made up of the components that accomplish the pumping task. The cylinder barrel, containing the piston shoe subassemblies, is driven via a splined drive shaft. The piston shoe subassemblies are constrained by a hold-down plate and utilize hydrostatically balanced shoes that run on the hanger surface.

As the barrel rotates, the pistons reciprocate within their bores, taking in and discharging fluid through a stationary valve plate interfacing with the port cap.

The hanger is supported by bearings that permit angular rotation about an axis perpendicular to the cylinder barrel centerline. By changing the angle of the hanger, the length of the piston stroke varies, resulting in a change in pump displacement.

During operation, pump discharge pressure is controlled by the compensator. The pressure compensator maintains the delivery pressure by regulating the hanger angle and subsequent discharge flow in response to changes in system pressure.

OPTIONAL FEATURES:
• Impeller – For performance at low inlet pressures, an impeller is used to ensure that the piston bores fill properly.
• Gerotor – A gerotor ensures case drain flow against the maximum back pressure of the system at the case drain port, decreasing the operating temperature of the rotating group and minimizing the pressure loads on the rotating group components.
• Depressurization – A depressurizing circuit overrides normal pressure compensator regulation, allowing for discharge pressure reduction and a subsequent input torque decrease.
• Blocking valve – Incorporated in conjunction with a depressurization circuit, a blocking valve will block flow out of the discharge port during depressurization.
• Attenuation – To minimize pressure ripple, pulsation dampeners can be incorporated into the pump design.
• Advanced bearings – This aerospace technology is designed to minimize weight and envelope.