Abstract: A flight control surface actuation system includes a rotary actuator having an output part configured to rotate about an axis (R-R), a connecting rod for connecting a flight control surface to the rotary actuator, and a connection mechanism connecting a first end of the connecting rod to the output part such that rotation of the output part about the axis causes at least part of the connection rod to rotate about the axis. The connection mechanism comprises a connection structure fixed to the output part and an engagement part mounted for rotation about a longitudinal axis. The engagement part extends through the connecting rod and is fixed to it. A position sensor is arranged to measure the angular displacement of the first end of the connecting rod about the axis.

Abstract: A strain wave gear mechanism includes: a casing; an elliptical drive shaft; an outer ring arranged coaxially around the elliptical drive shaft and rotationally fixed to the casing, the outer ring having a toothed inner circumference; a flexible ring mounted around the elliptical drive shaft radially inwards of the outer ring, the flexible ring having a toothed outer circumference. Rotation of the elliptical drive shaft causes elliptical rotation of the flexible ring relative to the outer ring such that teeth of the flexible ring engage with teeth of the outer ring at points corresponding to the major axis of the ellipse of the drive shaft to cause movement of the flexible ring in a direction opposite to rotation of the drive shaft. The outer ring is rotationally fixed to the casing via a solenoid operated disconnect gear configured to selectively disconnect the outer ring from the casing.

Abstract: A method of manufacturing a gear includes: providing a shaft; forming a groove into the shaft; and inserting a tooth into the groove such that the tooth is retained in the groove by an interference fit. A retainer can also be fixed to the shaft such that the tooth is retained in the groove by the retainer in addition to the interference fit.

Abstract: An electromechanical actuator assembly operable in a plurality of modes.

Abstract: A device for selectively transmitting torque between an input shaft and an output shaft includes: a first plurality of friction disks configured to rotate with the input shaft; a second plurality of friction disks configured to rotate with the output shaft and interdigitated with the first plurality of friction disks; a plurality of roller disks wherein each of the plurality of roller disks includes a first disk-to-roller interface with one of the first plurality of friction disks and a second disk-to-roller interface with one of the second plurality of friction disks; a first resilient member configured to provide a force (FSPR) through the first and second plurality of friction disks and roller disks; a solenoid configured to overcome the force (FSPR) from the resilient member when energised. the device may be selectively placed in one of a first mode and a second mode depending on torque requirements.

Abstract: A gear device for a gear system for an aircraft includes: an input stage epicyclic gear comprising an input stage sun, an input stage carrier and an input stage ring; and an output stage epicyclic gear comprising an output stage sun, an output stage carrier and an output stage ring. A first input stage component of the input stage sun, the input stage carrier and the input stage ring is fixed to a corresponding first output stage component of the output stage sun, the output stage carrier and the output stage ring, wherein a second input stage component of the input stage sun, the input stage carrier and the input stage ring is fixed to a corresponding second output stage component of the output stage sun, the output stage carrier and the output stage ring. The second input stage component is different from the first input stage component.

Abstract: An actuator system includes a motor and an actuator positioning member to be driven by the motor from a start position to an actuated position. The system also includes a harmonic drive assembly between the motor and the actuator positioning member arranged to transfer torque from the motor to the actuator positioning member at a gear ratio of greater than 1:1. The system further includes means for disconnecting the harmonic drive assembly in response to failure of the motor and/or torque transfer such as to allow the positioning member to return to the start position.

Abstract: An electromechanical actuator comprises: a motor; a gearbox; an anti-extension device mounted between the motor and the gearbox. The motor and anti-extension device are mounted on a housing of the actuator. The actuator further comprises a screw shaft; a nut mounted on the screw shaft; an output rod connected to the nut, the output rod having a linear range of motion defined between full extension of the output rod at a first end point (A) and full retraction of the output rod at a second end point (C). The screw shaft, nut, and output rod are located in a cavity of the housing. The output rod and nut are held against rotation relative to the housing, such that rotation of the screw shaft drives the output rod to move linearly within the housing.

Abstract: A strain wave gear mechanism includes: a casing; an elliptical drive shaft; an outer ring arranged coaxially around the elliptical drive shaft and rotationally fixed to the casing, the outer ring having a toothed inner circumference; a flexible ring mounted around the elliptical drive shaft radially inwards of the outer ring, the flexible ring having a toothed outer circumference. Rotation of the elliptical drive shaft causes elliptical rotation of the flexible ring relative to the outer ring such that teeth of the flexible ring engage with teeth of the outer ring at points corresponding to the major axis of the ellipse of the drive shaft to cause movement of the flexible ring in a direction opposite to rotation of the drive shaft. The outer ring is rotationally fixed to the casing via a solenoid operated disconnect gear configured to selectively disconnect the outer ring from the casing.

Abstract: An assembly is provided for an aircraft. This aircraft assembly includes an aircraft control surface. The aircraft control surface includes a first skin, a second skin and a support structure laterally between and connected to the first skin and the second skin. The support structure includes a spar, a first stiffener and a second stiffener. The spar extends spanwise within the aircraft control surface. The first stiffener extends longitudinally within the aircraft control surface to the spar. The second stiffener extends longitudinally within the aircraft control surface to the spar. An actuator receptacle projects longitudinally into the aircraft control surface from a base of the aircraft control surface to the spar. The actuator receptacle extends spanwise within the aircraft control surface between the first stiffener and the second stiffener.

Abstract: An actuator pressure intensifying assembly includes a mode valve and a gear motor assembly, the mode valve arranged to receive, at an input port, a supply pressure and to provide, at an output port, a control pressure to an actuator, the mode valve further configured to move, in response to the supply pressure exceeding a predetermined activation threshold, from a first mode in which the supply pressure flows directly from the input port to the output port in a first fluid flow path, and a second mode in which the supply pressure flows from the input port to the output port in a second fluid flow path which includes the gear motor assembly between the input port and the output port which intensifies the supply pressure such that the control pressure is higher than the supply pressure.

Abstract: An asymmetric torque limiter having an axis of rotation including a first annular friction disk, a second annular friction disk a skewed roller disk a first resilient member and a second resilient member. The second annular friction disk is concentrically arranged with the first annular friction disk. The skewed roller disk is in contact with the second annular friction disk. The skewed roller disk includes a plurality of skewed rollers mounted in an annular retainer. The plurality of skewed rollers are about a respective roller axis, each roller axis being skewed to a radial direction passing through the skewed roller from the axis of rotation. The first resilient member is attached to the first annular friction disk and is configured to bias the first annular friction disk toward an input shaft. The second resilient member is configured to bias the skewed roller disk toward the second annular friction disk.

Abstract: A system includes an electrically-actuated clutch arranged to selectively connect a shaft to a motor shaft. Ratchets brake the shaft against rotation in either direction when the output is not within either of the predetermined ranges. Thus, when the motor shaft is connected, via the clutch, to the shaft, the ratchets may act as a brake on the motor shaft.

Abstract: A wing panel actuator assembly includes: an actuator housing; an actuator piston arranged in the actuator housing and axially movable relative to the actuator housing; a connecting rod attached, at one end, to an end of the piston extending from the actuator housing; the actuator housing and piston arranged to be accommodated inside a movable panel of an aircraft wing. The connecting rod is arranged to be attached, in use, at its end opposite the one end attached to the piston, to a wing structure of the aircraft wing, the panel being pivotable about a pivot point P relative to the wing structure by means of the actuator piston.

Abstract: An assembly is provided for an aircraft. This aircraft assembly includes an aircraft control surface. The aircraft control surface includes a first skin, a second skin and a support structure laterally between and connected to the first skin and the second skin. The support structure includes a spar, a first stiffener and a second stiffener. The spar extends spanwise within the aircraft control surface. The first stiffener extends longitudinally within the aircraft control surface to the spar. The second stiffener extends longitudinally within the aircraft control surface to the spar. An actuator receptacle projects longitudinally into the aircraft control surface from a base of the aircraft control surface to the spar. The actuator receptacle extends spanwise within the aircraft control surface between the first stiffener and the second stiffener.

Abstract: An actuation system for a control surface for an aircraft includes a first, second, third and fourth actuator, a first and second bell crank, and at least one push pull rod system. Each of the first and second bell cranks comprises a first and a second crank arm, the first and second crank arms intersect with and are joined to each other at an intersection, the first and second crank arms extend from the intersection at an angle to each other, the first bell crank is pivotally connected to the sub-structure by a first pivot extending through the first bell crank's intersection, and the second bell crank is pivotally connected to the sub-structure by a second pivot extending through the second bell crank's intersection.

Abstract: An electromechanical actuator, EMA, having a plurality of modes. The EMA includes a housing, a motor fixed relative to the housing, the motor having an output shaft, the output shaft defining an axis (X) of the EMA and a first sun gear connected for rotation with the output shaft. The system includes an output arranged to be driven by rotation of the first sun gear, wherein the output is arranged to have a neutral position and to be movable away from the neutral position within a positive quadrant and away from the neutral position within a negative quadrant and a ratchet comprising a ratchet wheel and a pawl. The system also has a torque limiter having a predetermined torque limit and arranged to limit torque transfer between the first sun gear and the output.

Abstract: An assembly is provided for an aircraft. This aircraft assembly includes an aircraft control surface and a hydraulic actuator. The hydraulic actuator includes a housing and a piston within the housing. The housing is formed integral with the aircraft control surface.

Abstract: An electromechanical actuator (EMA) includes a plurality of modes and includes an electrical motor having a motor shaft extending along an axis (A) and that drives the shaft to rotate about the axis and a gear assembly mounted around, and in geared connection with the shaft, to rotate with the shaft. The EMA output is connected to the gear assembly such that rotation of the motor shaft causes rotation of the output via the gear assembly, the output rotating at a speed which is a predetermined fraction of the speed of rotation of the motor shaft based on the gear ratio of the gear assembly. The EMA also includes a synchroniser comprising a first conical portion connected to an end of the motor shaft, and a second conical portion connected to a ratchet. The synchroniser has an engaged position and a disengaged position.

Abstract: A device for damping rotary motion of a component. The device comprises a first part adapted to be mounted to the component so as to rotate therewith, and a second part adapted to be fixed such that the first part moves towards the second part when the component rotates in a first direction (D1). At least one surface of the first part and a corresponding at least one surface of the second part are angled such that, as the first part moves towards the second part, the at least one surface of the first part will move into contact with and then move along the corresponding at least one surface of the second part such that friction between the at least one surface of the first part and the corresponding at least one surface of the second part acts against the movement of the first part.