Abstract: A failsafe vale provides “Hole-In-The-Wall” failsafe functionality for thin-wing aircraft control surface actuation systems having a geared rotary actuator powered by a hydraulic rotary motor. The failsafe valve is associated with the hydraulic rotary motor and mechanically connected to the control surface, and enables the flight control surface to return to an aerodynamically neutral failsafe position if electrical control and/or hydraulic pressure is lost. When the failsafe valve receives a normal command pressure from the hydraulic system, the valve is inactive and the actuation system operates normally. However, if there is a loss of electrical command capacity to control hydraulic valves and/or a loss of hydraulic pressure, the failsafe valve is activated and connects one of the motor hydraulic control lines to the case return line for the motor if the control surface is away from its failsafe position.

Abstract: A stop module for non-jamming end-of-stroke stoppage of a rotary drive actuator includes timing gears to articulate a stopping pawl, and a low inertia, deformable stopping disk arranged to safely dissipate excess rotational kinetic energy of the rotary actuator. The stop module does not rely on friction to stop and dissipate the excess kinetic energy, but instead relies on predictable deformation of a metallic stopping disk which may be provided in a stopping cartridge of the stop module. Use of a deformable element to dissipate excess energy allows the disclosed stop module to be lighter and smaller than conventional end-of-stroke stopping mechanisms.

Abstract: A stop module for non-jamming end-of-stroke stoppage of a rotary drive actuator includes timing gears to articulate a stopping pawl, and a low inertia, deformable stopping disk arranged to safely dissipate excess rotational kinetic energy of the rotary actuator. The stop module does not rely on friction to stop and dissipate the excess kinetic energy, but instead relies on predictable deformation of a metallic stopping disk which may be provided in a stopping cartridge of the stop module. Use of a deformable element to dissipate excess energy allows the disclosed stop module to be lighter and smaller than conventional end-of-stroke stopping mechanisms.

Abstract: A failsafe vale provides “Hole-In-The-Wall” failsafe functionality for thin-wing aircraft control surface actuation systems having a geared rotary actuator powered by a hydraulic rotary motor. The failsafe valve is associated with the hydraulic rotary motor and mechanically connected to the control surface, and enables the flight control surface to return to an aerodynamically neutral failsafe position if electrical control and/or hydraulic pressure is lost. When the failsafe valve receives a normal command pressure from the hydraulic system, the valve is inactive and the actuation system operates normally. However, if there is a loss of electrical command capacity to control hydraulic valves and/or a loss of hydraulic pressure, the failsafe valve is activated and connects one of the motor hydraulic control lines to the case return line for the motor if the control surface is away from its failsafe position.

Abstract: A power spring passively applies tension to a cable connected to an aircraft refueling boom. The power spring has a first end engaging a fixed arbor and second end engaging a rotatable spooling drum around which a portion of the cable is wound. The power spring biases the drum to rotate in a winding direction to apply tension to the cable, and the power spring stores energy when the drum rotates in an unwinding direction. The power spring may be located inside the drum or outside the drum. The drum may be actively driven by a motor that may be uncoupled from the drum to permit freewheeling rotation of the drum, wherein the power spring continues to apply tension to the cable. The invention eliminates reliance on one or more powered motors for removing unwanted slack in the cable.

Abstract: A low-cost method of manufacturing a composite tube assembly having a composite fiber tube connected to metallic end fittings includes placing at least one end fitting on a mandrel, the end fitting including a grip region having a plurality of external surfaces, wrapping a fiber tow around the grip region of each end fitting and the mandrel to form a fiber-wrapped assembly, curing the fiber tow, and removing the mandrel to yield a completed tube assembly. The method may include positioning a plurality of compression inserts around the grip region after some of the fiber tow has been wrapped around the grip region, and wrapping additional fiber tow around the compression inserts and the grip region. The compression inserts may have a rounded outer surface such that an end portion of the tube wound around the compression inserts has a round outer cross-sectional shape.

Abstract: A torque transmission apparatus incorporates a differential gear system and a stationary sensor connected to the differential gear system for measuring output torque. The stationary sensor may be connected to a measurement output element of the differential gear system by a torsionally compliant measurement member, wherein the stationary sensor measures torsional deformation of the measurement member. The torsional deformation may be measured directly, or it may be measured following amplification by a gear train. A rotary position sensor may be used as the stationary sensor. Alternatively, the stationary sensor may be connected to the measurement output element of the differential gear system by way of a rigid measurement member, wherein the stationary sensor measures force applied by the measurement member. In this alternative, a force sensor may be used as the stationary sensor.

Abstract: An apparatus for connecting a rotational drive member to a rotational driven member brakes rotation when either the torque transmitted between the members exceeds a predetermined torque limit or the rotational speed of the drive member exceeds a predetermined rotational speed limit. The apparatus includes a torque limiter configured to actuate a braking mechanism or disconnect transmission when the torque limit is exceeded, and an over-speed governor configured to trigger the torque limiter when the rotational speed of the input element exceeds the rotational speed limit. The over-speed governor may trigger the torque limiter by reducing the torque limit of the torque limiter, or by introducing rotational drag in the apparatus to increase transmitted torque.

Abstract: An apparatus for connecting a rotational drive member to a rotational driven member brakes rotation when either the torque transmitted between the members exceeds a predetermined torque limit or the rotational speed of the drive member exceeds a predetermined rotational speed limit. The apparatus includes a torque limiter configured to actuate a braking mechanism or disconnect transmission when the torque limit is exceeded, and an over-speed governor configured to trigger the torque limiter when the rotational speed of the input element exceeds the rotational speed limit. The over-speed governor may trigger the torque limiter by reducing the torque limit of the torque limiter, or by introducing rotational drag in the apparatus to increase transmitted torque.

Abstract: A low-cost, lightweight telescoping torque tube assembly is reliable, safe, and easy to operate. The assembly has no loose fasteners, and no tools are required to operate the telescoping assembly. The telescoping torque tube assembly has only two parts, namely an end fitting and a torque tube. A resiliently deflectable locking tab is provided on one of the parts, and the locking tab is received by a corresponding locking slot formed in the other part. The locking tab has an abutment edge, and the locking slot has a limit edge facing the abutment edge for engaging the abutment edge when the locking tab is undeflected to prevent axially directed adjustment of the end fitting relative to the torque tube from an extended position toward a retracted position. A user deflects the locking tab to enable adjustment of the end fitting from the extended position to the retracted position.

Abstract: An electromechanical actuator (“EMA”) is provided with redundant load paths for driving the actuator stroke. The EMA includes a rotatable screw, a nut mated with the screw and having an external toothed surface, and a rotatable spline member having a splined surface engaging the external toothed surface of the nut. An actuator rod is coupled to the nut for linear movement with the nut. A first motor is operable to rotate the screw relative to the nut to cause the nut to travel linearly along the screw, and a second motor is operable to rotate the spline member and nut such that the nut travels linearly along the screw. Consequently, the actuator rod moves linearly by operation of the first motor alone, by operation of the second motor alone, and by simultaneous operation of the first and second motors. A no-back device may be incorporated into each load path.

Abstract: A low-cost method of manufacturing an all-composite composite torque tube includes winding fiber tow around a cylindrical mandrel and a plurality of eyelet forms held by an end fixture on the mandrel, whereby a flanged end coupling is formed. The method may include the use of a pre-woven composite fiber end sleeve configured to define the flanged end coupling. The wound fiber, and the end sleeve, are cured together in a single step. Metal eyelets may be installed in the bolt holes.

Abstract: A rotary lock apparatus comprises a structural ground and a shaft rotatable about a shaft axis relative to the structural ground, wherein the shaft includes a detent portion. First and second locking components are displaceable along the shaft axis in opposite directions to cause the detent portion to be engaged and coupled to the structural ground in a manner preventing rotation of the shaft about the shaft axis. The locking components are actuated through a combined displacement distance and are configured such that at least one of the first and second locking components positively causes the shaft to be engaged and coupled to the structural ground to thereby lock the shaft against rotation.

Abstract: A torque transmission apparatus incorporates a differential gear system and a stationary sensor connected to the differential gear system for measuring output torque. The stationary sensor may be connected to a measurement output element of the differential gear system by a torsionally compliant measurement member, wherein the stationary sensor measures torsional deformation of the measurement member. The torsional deformation may be measured directly, or it may be measured following amplification by a gear train. A rotary position sensor may be used as the stationary sensor. Alternatively, the stationary sensor may be connected to the measurement output element of the differential gear system by way of a rigid measurement member, wherein the stationary sensor measures force applied by the measurement member. In this alternative, a force sensor may be used as the stationary sensor.

Abstract: A low-cost method of manufacturing an all-composite composite torque tube includes winding fiber tow around a cylindrical mandrel and a plurality of eyelet forms held by an end fixture on the mandrel, whereby a flanged end coupling is formed. The method may include the use of a pre-woven composite fiber end sleeve configured to define the flanged end coupling. The wound fiber, and the end sleeve, are cured together in a single step. Metal eyelets may be installed in the bolt holes.

Abstract: A stop mechanism for a drive system includes a one-way clutch, a brake, a stop feature, and a linkage. The one-way clutch couples with a drive shaft of the system when the drive shaft is rotating in a first direction but not in an opposite direction. The brake is connected to the drive shaft through the first one-way clutch and is operable to stop drive shaft rotation in the first direction. The stop feature is carried by an output element driven by the drive shaft and actuates the linkage to operate the first brake when the output element reaches a predetermined limit position when moving in a direction corresponding to the first drive direction of the drive shaft. A bidirectional stop mechanism is provided by adding a second one-way clutch, a second brake, and a second stop feature arranged to act in the opposite rotational direction of the drive shaft.

Abstract: A low-cost method of manufacturing a composite tube assembly having a composite fiber tube connected to metallic end fittings includes placing at least one end fitting on a mandrel, the end fitting including a grip region having a plurality of external surfaces, wrapping a fiber tow around the grip region of each end fitting and the mandrel to form a fiber-wrapped assembly, curing the fiber tow, and removing the mandrel to yield a completed tube assembly. The method may include positioning a plurality of compression inserts around the grip region after some of the fiber tow has been wrapped around the grip region, and wrapping additional fiber tow around the compression inserts and the grip region. The compression inserts may have a rounded outer surface such that an end portion of the tube wound around the compression inserts has a round outer cross-sectional shape.

Abstract: A stop mechanism for a drive system includes a one-way clutch, a brake, a stop feature, and a linkage. The one-way clutch couples with a drive shaft of the system when the drive shaft is rotating in a first direction but not in an opposite direction. The brake is connected to the drive shaft through the first one-way clutch and is operable to stop drive shaft rotation in the first direction. The stop feature is carried by an output element driven by the drive shaft and actuates the linkage to operate the first brake when the output element reaches a predetermined limit position when moving in a direction corresponding to the first drive direction of the drive shaft. A bidirectional stop mechanism is provided by adding a second one-way clutch, a second brake, and a second stop feature arranged to act in the opposite rotational direction of the drive shaft.

Abstract: A low-cost, lightweight telescoping torque tube assembly is reliable, safe, and easy to operate. The assembly has no loose fasteners, and no tools are required to operate the telescoping assembly. The telescoping torque tube assembly has only two parts, namely an end fitting and a torque tube. A resiliently deflectable locking tab is provided on one of the parts, and the locking tab is received by a corresponding locking slot formed in the other part. The locking tab has an abutment edge, and the locking slot has a limit edge facing the abutment edge for engaging the abutment edge when the locking tab is undeflected to prevent axially directed adjustment of the end fitting relative to the torque tube from an extended position toward a retracted position. A user deflects the locking tab to enable adjustment of the end fitting from the extended position to the retracted position.

Abstract: A rotary lock apparatus comprises a structural ground and a shaft rotatable about a shaft axis relative to the structural ground, wherein the shaft includes a detent portion. First and second locking components are displaceable along the shaft axis in opposite directions to cause the detent portion to be engaged and coupled to the structural ground in a manner preventing rotation of the shaft about the shaft axis. The locking components are actuated through a combined displacement distance and are configured such that at least one of the first and second locking components positively causes the shaft to be engaged and coupled to the structural ground to thereby lock the shaft against rotation.