Actuator Assembly

• US 20180031093A1
• Filed: 07/26/2017
• Published: 02/01/2018
• Est. Priority Date: 07/27/2016
• Status: Active Grant

• Current Assignee: Ratier Figeac (Raytheon Technologies Corporation d/b/a RTX)
• Original Assignee: Ratier Figeac (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: SEMINEL, Bruno, VERMANDE, Frdric
• Granted Patent: US 10,598,265 B2
• Time in Patent Office: Days
• CPC Class Codes: B64C 13/341 having duplication or stand-by provisions
• CPC Class Codes: B64D 2045/0085 Devices for aircraft health monitoring, e.g. monitoring flutter or vibration
• CPC Class Codes: F16H 2025/2037 Actuator supports or means for fixing piston end, e.g. flanges
• CPC Class Codes: F16H 2025/2081 Parallel arrangement of drive motor to screw axis
• CPC Class Codes: F16H 2057/012 of gearings
• CPC Class Codes: F16H 25/2015 Means specially adapted for stopping actuators in the end position; Position sensing means
• CPC Class Codes: F16H 25/2021 with means for avoiding overloading
• CPC Class Codes: F16H 25/2454 Brakes; Rotational locks
• CPC Class Codes: F16H 57/01 Monitoring wear or stress of gearing elements, e.g. for triggering maintenance
• CPC Class Codes: F16H 57/025 Support of gearboxes, e.g. torque arms, or attachment to other devices
• CPC Class Codes: G01L 1/26 Auxiliary measures taken, or devices used, in connection with the measurement of force, e.g. for preventing influence of transverse components of force, for preventing overload
• CPC Class Codes: G01L 5/0061 Force sensors associated with industrial machines or actuators for the specific machine or actuator involved see relevant class, e.g. F01, F04, F16, B66, E21
• CPC Class Codes: G07C 5/0808 Diagnosing performance data testing of vehicles G01M17/00; testing of electrical installation on vehicles G01R31/005
• CPC Class Codes: G07C 5/0816 Indicating performance data, e.g. occurrence of a malfunction

Abstract

An actuator assembly may comprise a screw shaft having a shaft axis; a drive arrangement pivotally supported about the screw shaft axis for driving the screw shaft, e.g., about the shaft axis or along the shaft axis, and a rod mounted to the drive arrangement at a location off the shaft axis for providing a primary function of reacting torque about the shaft axis on the drive arrangement. The rod may comprise a rod axis and provide a load path along the rod axis for reacting torque. The rod may also comprise a device for which provides a secondary function for the actuator assembly based on the load experienced along the load path provided by the rod.

Claims

1. An actuator assembly comprising:

a screw shaft having a shaft axis;

a drive arrangement pivotally supported about the screw shaft axis for driving the screw shaft; and

a rod mounted to the drive arrangement at a location off the shaft axis for providing a primary function of reacting torque about the shaft axis on the drive arrangement, the rod having a rod axis and being arranged to provide a load path that experiences load in a direction along the rod axis in reaction to torque on the drive arrangement,

wherein the rod comprises a device which provides a secondary function for the actuator assembly based on the load experienced along the rod load path.

2. The actuator assembly as claimed in claim 1, wherein the device comprises a resilient mechanism, preferably a spring arrangement.

3. The actuator assembly as claimed in claim 2, wherein the device comprises a load limiter which activates to limit axial forces in the rod.

4. The actuator assembly as claimed in claim 3, wherein relative movement of a nut along the screw shaft is limited by metal end stops.

5. The actuator assembly as claimed in claim 1, wherein the device is for detecting a performance of the actuator assembly based on load experienced along the rod load path reacting torque on the drive arrangement, wherein the device comprises a load limiter configured to control a change in length of the rod through axial movement of one portion relative to another when a load along the rod load path exceeds a pre-load of the load limiter, and wherein the device comprises an activation sensor for detecting a change of length of the rod.

6. The actuator assembly as claimed in claim 1, comprising a no-back device, wherein the no-back device is connected with a rotational coupling to a frame and the drive arrangement is supported on bearings permitting the drive arrangement to rotate about the screw shaft axis and about the no-back device.

7. The actuator as claimed in claim 6, wherein the device comprises a load sensor for detecting at least a direction of the load along the rod load path, and preferably wherein the load sensor is arranged to transmit load signals to a processor which is programmed with an algorithm to compute parameters comprising a fatigue life consumption and/or endurance life consumption of one or more components of the actuator assembly.

8. The actuator assembly as claimed in claim 6, wherein the actuator assembly comprises a processor configured to receive a movement signal indicating a direction of drive of the screw shaft from a movement sensor and to receive a direction of load signal from the load sensor, wherein the processor is configured to determine, from the direction of load signal and the movement signal, whether or not the drive arrangement is operating in a resistive load quadrant or a load driven quadrant.

9. The actuator assembly as claimed in claim 8, wherein the processor is configured to:

output a performance signal indicating whether the drive arrangement is operating in a resistive load quadrant or a load driven quadrant.

10. The actuator assembly as claimed in claim 1, wherein the actuator assembly further comprises a second rod for reacting torque on the no-back device into the frame, the second rod being provided with a device which provides a secondary function for the actuator assembly based on load experienced along the second rod.

11. The actuator assembly as claimed in claim 10, wherein the device in the second rod is a load sensor which provides a load signal for use in monitoring the operation and/or health of the actuator assembly.

12. A method of reacting torque on an actuator assembly, wherein the actuator assembly comprises a screw shaft having a shaft axis, a drive arrangement pivotally supported about the screw shaft axis for driving the screw shaft, and a rod for connection to a frame, wherein one end of the rod is connected to the drive arrangement at a location off the shaft axis, the rod having a rod axis along which load is experienced resulting from torque on the drive arrangement;

the method comprising;

using the rod to provide a load path which can react torque on the drive arrangement as a primary function of the rod; and

using the rod load path to operate a device which is part of the rod in order to provide a secondary function for the actuator assembly based on the load experienced along the rod load path.

13. The method of reacting torque as claimed in claim 12, wherein the device provides a secondary function of reducing angular impulses on the actuating assembly.

14. The method of reacting torque as claimed in claim 12, wherein the device comprises portions that move with respect to each other against a bias.

15. The method of reacting torque as claimed in claim 12, wherein the method comprises providing a rod with a device comprising a load limiter.

16. The method of reacting torque as claimed in claim 12, wherein the method of reacting torque includes a secondary function of detecting a performance of the actuator assembly based on load experienced along the rod load path in reaction to torque on the drive arrangement.

17. The method of reacting torque as claimed in claim 16, wherein the detecting a performance comprises:

detecting at least a direction of the load along the rod load path using a load sensor which is provided in the rod load path, and preferably wherein the detecting comprises detecting a direction and magnitude of the load along the rod load path.

18. The method of reacting torque as claimed in claim 17, wherein load signals from the load sensor are used to compute parameters comprising a fatigue life consumption and/or endurance life consumption of one or more components of the actuator assembly.

19. The method of reacting torque as claimed in claim 17, wherein the detecting a performance of an actuator assembly comprises:

sensing a direction of drive of the screw shaft; and

processing information concerning the direction of the load and the direction of drive to determine a first performance status of the actuator assembly when the drive arrangement is operating in a resistive load quadrant and to determine a second performance status of the actuator assembly when the drive arrangement is operating in a load driven quadrant,

and preferably wherein a signal is outputted if a second performance status is determined.

20. The method of reacting torque as claimed in claim 16, wherein the detecting a performance of an actuator assembly comprises:

controlling a change in a length of the rod through compaction or stretching of a resilient mechanism when a load along the rod load path exceeds a pre-load of the resilient mechanism;

biasing the rod when the pre-load is exceeded in either tension or compression to return it back to an initial length; and

detecting activation of the resilient mechanism through the change of length of the rod.