Patent attributes
An electro hydrostatic actuator system for retracting/extending a landing gear includes a plurality of hydraulic actuators, a plurality of hydraulic supply sources each including a single hydraulic pump and a single electric motor, provided in parallel to each other and joined at the downstream ends, a plurality of switching valves provided in parallel on a supply path that connects the hydraulic actuators to a junction of the hydraulic supply sources, and a controller configured to sequentially operate the hydraulic actuators. The hydraulic supply sources each include a check valve which prevents operation oil from flowing toward the hydraulic pump. In a normal state, the hydraulic supply sources together supply operation oil sequentially to the hydraulic actuators. When any of the hydraulic supply sources is failed, the other hydraulic supply source(s) other than the failed hydraulic supply source supplies operation oil sequentially to the hydraulic actuators.
