Electrohydraulic actuators linear actuation product

The Electrohydraulic actuators is a linear actuator from Parker Aerospace with aerospace-grade grade and dual-use market. Electrohydraulic actuators from Parker Aerospace are linear actuation products that turn an electrical command from a flight control computer into controlled linear movement of a control surface or mechanism through hydraulic force. Parker, a supplier of flight control actuation, offers two related architectures that fall under this heading: electrohydraulic servo actuators and electrohydrostatic actuators.

In an electrohydraulic servo actuator, a servovalve driven by the electrical signal meters hydraulic fluid to a cylinder. Parker describes its fly-by-wire actuators as using Jet-Pipe electrohydraulic servovalve technology or direct drive valve technology, with commands received from the flight control computer and converted into surface motion. These units draw on an aircraft hydraulic supply.

An electrohydrostatic actuator removes the need for a central hydraulic system. A brushless DC motor drives a fixed-displacement, high-speed, reversible pump; the direction of pump rotation sets the direction of the cylinder and the pump speed sets its speed. The fluid circuit is local to the actuator, so the aircraft supplies electrical power and a command signal instead of hydraulic lines. Parker describes fail-safe features, overload protection and packaging that reduces weight in these designs, and its aerospace units cover a power range from 1 kW to 25 kW.

For integration, the mechanical interface, stroke, force, supply voltage and command interface are defined by the actuator configuration for each platform. The control electronics are matched to the brushless motor, so the flight control computer sends a position command and receives feedback. An integrator should review the configuration with the maker.

Typical applications are primary and secondary flight control surfaces of aircraft, and other positioning tasks where high force at a small package size is needed.