Abstract: A torque motor has a mechanical reference member, an armature, and a field assembly. The field assembly includes field pole pieces defining a pole opening, and the armature is mounted to the mechanical reference member for rotation about a motor axis and extends into the pole opening with respective gaps to the field pole pieces. The field assembly is secured to the mechanical reference member and spaced therefrom by elastically deformable flexures, deformed sufficiently to locate the armature at a predetermined position within the pole openings with corresponding lengths of the gaps. During manufacture, a load can be applied to move the field assembly relative to the mechanical reference member against the deformation force of the flexures to locate the pole opening relative to the armature pole piece such that the gaps of desired lengths are formed.

Abstract: A thrust reverser actuation system for a jet engine having a turbine engine surrounded by a nacelle to define an annular air flow path between the turbine engine and the nacelle, with a thrust reverser having a movable element to reverse the direction of at least a portion of the air flow along the air flow path, where the thrust reverser actuation system includes a hydraulic actuator configured to be operably coupled to the movable element, and a remote actuator that controls the inhibit function of the hydraulic system.

Abstract: In some aspects, an aircraft engine thrust reverser lock system includes a pin-capturing member. The pin-capturing member includes a body that is rotatable about an axis defined by a pivot extending through the body. The body includes an interior surface that defines a slot. The slot has an opening that is sized to receive a pin into the slot. One side of the slot includes a protruded sidewall surface that protrudes into the slot toward an another sidewall surface of the slot. The protruded sidewall surface defines an apex between the open and closed ends of the slot. Between the apex and the closed end of the slot, the protruded sidewall surface faces the rotational axis.

Abstract: An apparatus includes a housing which defines a longitudinal axis; a positioning element which, relative to the housing, translates linearly along the longitudinal axis; and a rotational member which, relative to the housing, rotates about the longitudinal axis as the positioning element translates linearly along the longitudinal axis. The rotational member defines a helix to receive torque from the positioning element as the positioning element translates linearly along the longitudinal axis. The apparatus further includes a first sensor assembly to detect minor angular displacement of the rotational member (e.g., less than 360 degrees). The apparatus further includes a second sensor assembly to detect major angular displacement of the rotational member (e.g., a number of full 360 degree rotations). Such detection is capable of identifying a full angular displacement of the rotational member in response to linear translation of the positioning element from an initial position to a sensed position.

Abstract: A thrust reverser actuation system for a jet engine having a turbine engine surrounded by a nacelle to define an annular air flow path between the turbine engine and the nacelle, with a thrust reverser having a movable element to reverse the direction of at least a portion of the air flow along the air flow path, where the thrust reverser actuation system includes a hydraulic actuator configured to be operably coupled to the movable element, and a remote actuator that controls the inhibit function of the hydraulic system.

Abstract: In some aspects, an aircraft engine thrust reverser lock system includes a pin-capturing member. The pin-capturing member includes a body that is rotatable about an axis defined by a pivot extending through the body. The body includes an interior surface that defines a slot. The slot has an opening that is sized to receive a pin into the slot. One side of the slot includes a protruded sidewall surface that protrudes into the slot toward an another sidewall surface of the slot. The protruded sidewall surface defines an apex between the open and closed ends of the slot. Between the apex and the closed end of the slot, the protruded sidewall surface faces the rotational axis.

Abstract: An apparatus includes a housing which defines a longitudinal axis; a positioning element which, relative to the housing, translates linearly along the longitudinal axis; and a rotational member which, relative to the housing, rotates about the longitudinal axis as the positioning element translates linearly along the longitudinal axis. The rotational member defines a helix to receive torque from the positioning element as the positioning element translates linearly along the longitudinal axis. The apparatus further includes a first sensor assembly to detect minor angular displacement of the rotational member (e.g., less than 360 degrees). The apparatus further includes a second sensor assembly to detect major angular displacement of the rotational member (e.g., a number of full 360 degree rotations).

Abstract: A method of locking a linear output member in a retracted position within a linear actuator, where the linear output member is capable of axial motion within a housing of the linear actuator, includes rotating a generally tubular rotor disposed within a rotary lock assembly of the actuator to a first rotor position, and shifting a lock capable of radial displacement within the rotary lock assembly based on rotating the rotor to the first position. The lock engages a radial groove of the linear output member when the linear output member is in a retracted position. The rotary lock assembly is constrained from axial motion. The radial groove of the linear output member includes an axially angled, substantially planar surface. The lock is configured to include an axially angled surface shaped complimentary to the axially angled, substantially planar surface of the radial groove.

Abstract: A direct drive servovalve (10) includes redundant drive motors (14) coupled to a common valve drive shaft (22,24) by a connection device (26). The connection device (26) is configured to allow operation of the servovalve (10) in the case where one or more of the drive motors (14) becomes inoperable, such as caused by jamming or binding of a rotor associated with the drive motor. By use of the connection device (26), in the event that one of the drive motors (14) was to become jammed, the remaining operable motors (14) can continue to stroke or cause translation of a valve member (18) of the direct drive servovalve (10) to allow its continued operation.

Abstract: An improved technique for controlling an electro-mechanical actuator combines a sliding mode of control with a second mode of control. An error signal is generated based on the difference between an input position signal and a feedback position signal. When the error signal is above a predetermined threshold, the actuator is controlled in the sliding control mode. When the error signal is below the predetermined threshold, the actuator is controlled in the second control mode. The combination of the sliding control mode with the second control mode yields a robust controller that can tolerate large parameter variations and uncertainties without sacrificing precise steady state tracking.

Abstract: An automatically locking actuator includes a first end connector, a rotatable drive screw operably coupled to the first end connector, a nut assembly threadably mounted on the drive screw, a second end connector operably coupled to the nut assembly and a rotary lock having a rotor and where the actuator moves between extended and retracted positions in response to rotation of the rotor.

Abstract: In some aspects, an aircraft engine thrust reverser lock system includes a pin-capturing member. The pin-capturing member includes a body that is rotatable about an axis defined by a pivot extending through the body. The body includes an interior surface that defines a slot. The slot has an opening that is sized to receive a pin into the slot. One side of the slot includes a protruded sidewall surface that protrudes into the slot toward an another sidewall surface of the slot. The protruded sidewall surface defines an apex between the open and closed ends of the slot. Between the apex and the closed end of the slot, the protruded sidewall surface faces the rotational axis.

Abstract: A method of locking a linear output member in a retracted position within a linear actuator, where the linear output member is capable of axial motion within a housing of the linear actuator, includes rotating a generally tubular rotor disposed within a rotary lock assembly of the actuator to a first rotor position, and shifting a lock capable of radial displacement within the rotary lock assembly based on rotating the rotor to the first position. The lock engages a radial groove of the linear output member when the linear output member is in a retracted position. The rotary lock assembly is constrained from axial motion. The radial groove of the linear output member includes an axially angled, substantially planar surface. The lock is configured to include an axially angled surface shaped complimentary to the axially angled, substantially planar surface of the radial groove.

Abstract: A thrust reverser actuation system for a jet engine having a turbine engine surrounded by a nacelle to define an annular air flow path between the turbine engine and the nacelle, with a thrust reverser having a movable element to reverse the direction of at least a portion of the air flow along the air flow path, where the thrust reverser actuation system includes a hydraulic actuator configured to be operably coupled to the movable element, and a remote actuator that controls the inhibit function of the hydraulic system.

Abstract: A thrust reverser assembly for use in a turbofan engine assembly. The engine assembly includes a core gas turbine engine and a core cowl which circumscribes the core gas turbine engine. A nacelle is positioned radially outward from the core cowl to define a fan nozzle duct between the core cowl and a portion of the nacelle. The nacelle includes a stationary cowl. The thrust reverser assembly includes a first translating cowl that is slidably coupled to the nacelle. The first translating cowl is positionable with respect to the stationary cowl. A second translating cowl is slidably coupled to the nacelle such that the first translating cowl is positioned between the stationary cowl and the second translating cowl. The second translating cowl is positionable with respect to the first translating cowl. A positioning assembly is coupled to the first translating cowl. An actuator assembly is operatively coupled to the second translating cowl for selectively moving the second translating cowl.

Abstract: A linear actuator is disclosed. The linear actuator includes a housing, a linear output member, and a rotary lock assembly. The linear output member includes a radial groove and is axially movable from a retracted position within the housing. The rotary lock assembly is constrained from axial motion within the housing and includes a rotor and a lock. The rotor is capable of rotation from a first to a second position. When the linear output member is in the retracted position, the rotor surrounds the radial groove. When the rotor rotates to the first position, the lock engages the radial groove and prevents axial motion of the output member from the retracted position.

Abstract: An improved technique for controlling an electro-mechanical actuator combines a sliding mode of control with a second mode of control. An error signal is generated based on the difference between an input position signal and a feedback position signal. When the error signal is above a predetermined threshold, the actuator is controlled in the sliding control mode. When the error signal is below the predetermined threshold, the actuator is controlled in the second control mode. The combination of the sliding control mode with the second control mode yields a robust controller that can tolerate large parameter variations and uncertainties without sacrificing precise steady state tracking.

Abstract: A floating piston actuator for use with multiple hydraulic systems includes a housing and a piston assembly. The piston assembly includes an elongate shaft or ram, at least one secured piston coupled to the ram, and a set of moveable pistons moveably disposed within the housing chamber on the ram such that the set of moveable pistons are translatable relative to a longitudinal axis of the ram. The set of moveable pistons form at least three hydraulically separate actuator cylinders where each of the three hydraulically separate actuator cylinders are disposed in fluid communication with a corresponding pressurized fluid source. The floating piston actuator allows hydraulic redundancy while maintaining a similar length compared to existing multi-system actuators. The floating pistons can be arranged in multiple configurations to allow operation with a hydraulic system failure without force fight or binding and with a higher output force than conventional multi-system actuators.

Abstract: A shift lock assembly includes a drive member carried by a drive shaft and configured to rotatably couple to a drive motor and a shift mechanism disposed between the drive member and a ground plate, the shift mechanism configured to move between a first position and a second position relative to the drive member and the ground plate. When disposed in the first position, the shift mechanism is configured to couple the drive shaft to the ground plate and decouple the drive shaft from the drive member to allow rotation of the drive member relative to the drive shaft. When disposed in the second position, the shift mechanism is configured to couple the drive shaft to the drive member and decouple the drive shaft from the ground plate to allow rotation of the drive shaft in response to rotation of the drive member.

Abstract: A servovalve torque motor includes first and second pole pieces and an armature. Each of the first and second pole pieces includes an armature face that opposes the armature. The area of the armature face of the second pole piece is smaller than the area of the armature face of the first pole piece. The unequal areas of the first and second armature faces create a bias in the servovalve torque motor while allowing the first and second pole pieces to be disposed at equal distances from the armature to define substantially equal air gaps. The inclusion of substantially equal air gaps between the pole pieces and the armature reduces the maximum flux in the armature for the same bias and torque output, compared to conventional servovalve torque motors. The reduction in maximum armature flux decreases armature saturation and improves linearity during operation.