Abstract: A driving stage of a servo valve, including a hydraulic ejector and a hydraulic receiver able to be moved relative to each other, one of the two hydraulic units being integral with a mobile unit, movable relative to a body of the servo valve through actuation means, characterized in that the actuation means comprise two piezoelectric actuators connected in series. Control device comprising a servo valve comprising such a driving stage.

Abstract: A driving stage of a servo valve, including a hydraulic ejector and a hydraulic receiver able to be moved relative to each other, one of the two hydraulic units being integral with a mobile unit, movable relative to a body of the servo valve through actuation means, characterized in that the actuation means comprise two piezoelectric actuators connected in series. Control device comprising a servo valve comprising such a driving stage.

Abstract: Hydraulic servo valve (1) comprising: a power stage (3) comprising a power distribution member able to move between two extreme positions in order to place one or more service portions (C1, C2) in communication with a feed port (P) supplying hydraulic fluid and with a return port (R); a control stage (4) for controlling the position of the power distribution member, the control stage (4) comprising a torque motor (MC) that can be operated in such a way as to actuate a fluid ejection member secured to an elastically deformable element and designed to cause a control pressure of the power distribution member to vary; characterized in that the fluid ejection member comprises a first and a second fluid injector (60, 63) which are fed by fluid feed means able to feed either just one of the first and second fluid injectors (60, 63) or both injectors simultaneously.

Abstract: Hydraulic servo valve (1) comprising: a power stage (3) comprising a power distribution member able to move between two extreme positions in order to place one or more service portions (C1, C2) in communication with a feed port (P) supplying hydraulic fluid and with a return port (R); a control stage (4) for controlling the position of the power distribution member, the control stage (4) comprising a torque motor (MC) that can be operated in such a way as to actuate a fluid ejection member secured to an elastically deformable element and designed to cause a control pressure of the power distribution member to vary; characterized in that the fluid ejection member comprises a first and a second fluid injector (60, 63) which are fed by fluid feed means able to feed either just one of the first and second fluid injectors (60, 63) or both injectors simultaneously.

Abstract: A servo-control system for actuating an aircraft flight control member, the system including at least one hydraulic actuator together with actuation means for actuating said actuator, said hydraulic actuator being duplicated, said actuation means including first and second actuation assemblies each comprising two hydraulic circuits each controlled by a respective mechanically-controlled distributor valve, the two distributor valves of the same actuation assembly being actuated by common mechanical elements caused to move by motor means, the actuation means including control means controlling said motor means as a function of the position of the flight control member and of piloting orders received by the control means, detection means for detecting failures, and a selector valve which controls switching of the actuation assemblies between an active state and a reserve state.