Abstract: An actuator (30) for actuating translation movement of a component (32) (e.g., a horizontal stabilizer) relative to a structure (34) (e.g., an aircraft's rear fuselage). The actuator (30) comprises a control-motion-providing assembly (40) having a drive path from a motion provider (52) to the component (32), a motion-permit-prevent assembly (42), and a sensing system (94) which senses a failure in the drive path. The motion-permit-prevent assembly (42) comprises a screw member (74), which is not part of the drive path, and a nut member (76). Upon detection drive-path failure by the sensing system (94), the motion-permit-prevent assembly (42) converts from a motion-permitting mode (whereat relative rotation between the screw-nut members (74/76) is permitted) to a motion-preventing mode (whereat relative rotation of the screw-nut members (74/76) is prevented). In the motion-preventing mode, the component (32) is locked or immobilized.

Abstract: The invention provides a method for controlling an electromechanical servomechanism (20) for moving an output member relative to a variable load (38). The servomechanism includes: a motor (37) having at least one coil (32A, 32B or 32C) adapted to be supplied with current and having a rotor (33) with an output shaft (35); a mechanical transmission (36) arranged between the output shaft and the load, the transmission having a mechanical friction related to the load; a servoamplifier (30) arranged to supply current to the motor coil in response to an input signal (in line 29); a command signal (in line 21) for commanding the position of the load; a load position feedback signal (in line 23) compared (in summing point 22) to the command signal and arranged to produce an error signal (in line 24); and means (28) for generating an offset signal (in line 26) that is summed (in summing point 25) with the error signal to modify the servoamplifier input signal (in line 29).

Abstract: The invention provides a method for controlling an electromechanical servo-mechanism (20) for moving an output member relative to a variable load (38). The servomechanism includes: a motor (37) having at least one coil (32A, 32B or 32C) adapted to be supplied with current and having a rotor (33) with an output shaft (35); a mechanical transmission (36) arranged between the output shaft and the load, the transmission having a mechanical friction related to the load; a servoamplifier (30) arranged to supply current to the motor coil in response to an input signal (in line 29); a command signal (in line 21) for commanding the position of the load; a load position feedback signal (in line 23) compared (in summing point 22) to the command signal and arranged to produce an error signal (in line 24); and means (28) for generating an offset signal (in line 26) that is summed (in summing point 25) with the error signal to modify the servoamplifier input signal (in line 29).

Abstract: A pressure-control device (20) includes a controllable variable-displacement reversible hydraulic motor (21) having a pressure port (22) and a return port (23); a source of pressurized fluid (Ps); a fluid return (R); and a pressure regulating valve (24) operatively interposed between the source, return and pressure port. The pressure regulating valve is operatively arranged to maintain a predetermined pressure at the pressure port regardless of the direction of flow through the pressure port.

Abstract: A pressure-control device (20) includes a controllable variable-displacement reversible hydraulic motor (21) having a pressure port (22) and a return port (23); a source of pressurized fluid (Ps); a fluid return (R); and a pressure regulating valve (24) operatively interposed between the source, return and pressure port. The pressure regulating valve is operatively arranged to maintain a predetermined pressure at the pressure port regardless of the direction of flow through the pressure port.

Abstract: A skewed roller brake assembly (20) has a main axis of rotation (x—x), has a first plate (21) adapted to be rotated about the main axis, has a second plate (22) adapted to be rotated relative to the first plate about the main axis, and has an intermediate plate (23) positioned between the first and second plates. The first and second plates are adapted to be axially loaded with respect to one another. The intermediate plate has a plurality of slots (25). Each slot is bounded by a first wall (26) that is arranged at a first angle (&thgr;1) with respect to a radius from the main axis. A cylindrical roller (25) is arranged in each slot for rolling engagement with the first and second plates about the axis of the roller such that the roller axis (y—y) is parallel to the first wall when the first and second plates are rotated relative to one another in one angular direction.

Abstract: A force-limiting rotary lock (20) for a shaft (21) mounted on a housing (22) for rotational and axial movement relative thereto, broadly includes a lug member (28) provided on the shaft, and a pawl (51) mounted on the housing. The pawl is movable relative to the housing between first and second positions. The pawl is operatively arranged to engage the lug when the pawl is in its first position (shown in FIG. 3) to prevent further rotation of the shaft in one angular direction, and to be disengaged from the lug when the pawl is in its second position (shown in FIG. 2) to permit rotation of the shaft in either angular direction. A cam (25) is mounted on the shaft, and a follower (49) is mounted on the housing for selectively moving the pawl between the first and second positions when the shaft is axially displaced from its predetermined position.

Abstract: A force-limiting rotary lock (20) for a shaft (21) mounted on a housing (22) for rotational and axial movement relative thereto, broadly includes a lug member (28) provided on the shaft, and a pawl (51) mounted on the housing. The pawl is movable relative to the housing between first and second positions. The pawl is operatively arranged to engage the lug when the pawl is in its first position (shown in FIG. 3) to prevent further rotation of the shaft in one angular direction, and to be disengaged from the lug when the pawl is in its second position (shown in FIG. 2) to permit rotation of the shaft in either angular direction. A cam (25) is mounted on the shaft, and a follower (49) is mounted on the housing for selectively moving the pawl between the first and second positions when the shaft is axially displaced from its predetermined position.

Abstract: A differential coupling (20) has a body (21), a rotary input member (22), and two rotary output shafts (23, 24). The algebraic sum of the angular displacements of the output shafts is proportional to the rotation of the input member. The improvement includes mechanical means (39), such as a planetary gear (42), for sensing a torque differential between the output shafts, and a brake (38) mounted on the body and operatively arranged to selectively brake rotation of the input member, or both output members, when the difference between the torques on the outputs exceeds a predetermined first value.

Abstract: A differential coupling (20) has a body (21), a rotary input member (22), and two rotary output shafts (23, 24). The algebraic sum of the angular displacements of the output shafts is proportional to the rotation of the input member. The improvement includes mechanical means (39), such as a planetary gear (42), for sensing a torque differential between the output shafts, and a brake (38) mounted on the body and operatively arranged to selectively brake rotation of the input member, or both output members, when the difference between the torques on the outputs exceeds a predetermined first value.