HORIZONTAL STABILIZER TRIM ACTUATOR FAILURE DETECTION SYSTEM AND METHOD USING POSITION SENSORS

• US 20130001357A1
• Filed: 07/02/2012
• Published: 01/03/2013
• Est. Priority Date: 06/30/2011
• Status: Active Grant

• Current Assignee: Parker Intangibles LLC (Parker-Hannifin Corporation)
• Original Assignee: Parker-Hannifin Corporation
• Inventors: Cyrot, Luc P.
• Granted Patent: US 10,065,728 B2
• Time in Patent Office: Days
• US Class Current: 244/99.4
• CPC Class Codes: B64C 13/341 having duplication or stand-by provisions
• CPC Class Codes: B64C 13/343 overriding of personal controls; with automatic return to inoperative position
• CPC Class Codes: B64C 13/505 having duplication or stand-by provisions
• CPC Class Codes: B64C 13/506 overriding of personal controls; with automatic return to inoperative position

Abstract

An actuator assembly having a primary load path for tightly coupling an actuated surface to a reference structure and a secondary load path having a backlash portion for coupling the actuated surface to the reference structure with backlash, wherein the secondary load path is unloaded during an operative state of the primary load path and loaded during a failure state of the primary load path. The actuator assembly includes at least one sensor configured to sense the failure state of the primary load path when a relative displacement between a portion of the primary load path and a portion of the secondary load path exceeds a predetermined value or is within a predetermined range of values.

Claims

1. An actuator assembly comprising:

a primary load path for tightly coupling an actuated surface to a reference structure;

a secondary load path having a backlash portion for coupling the actuated surface to the reference structure with backlash, wherein the secondary load path is unloaded during an operative state of the primary load path and loaded during a failure state of the primary load path; and

a first sensor configured to sense the failure state of the primary load path when a relative displacement between a portion of the primary load path and a portion of the secondary load path exceeds a predetermined value.

2. The actuator system of claim 1, wherein the sensor is a position sensor.

3. The actuator system of claim 2, wherein the sensor is a linear variable differential transducer.

4. The actuator system of claim 1, wherein the first sensor is configured to detect a failure state in one of an upper or lower primary attachment system.

5. The actuator system of claim 4, wherein the first sensor is configured to detect a failure state in at least one of a main housing, gimbal, primary attachment pins, or the ballscrew of the primary load path.

6. The actuator system of claim 4, wherein the first sensor configured to detect a failure state in at least one of a primary nut gimbal housing, primary ball nut assembly, or trunnion.

7. The actuator system of claim 4, further comprising a second sensor configured to detect a failure state in the other one of an upper or lower primary attachment system.

8. The actuator system of claim 1, further comprising a locking mechanism for engaging the secondary load path including manually resettable locking keys engageable under a tension load.

9. The actuator system of claim 8, wherein the locking mechanism for engaging the secondary load path further includes manually resettable locking key retainers triggerable under a tension load.

10. A method for handling failure of a primary load path of an actuator comprising:

receiving sensor signals from one or more sensors;

determining a relative displacement between a portion of the primary load path and a portion of a secondary load path based on the received signals;

comparing the relative displacement to a predetermined range of values; and

annunciating a failure of the primary load path if the relative displacement is within the predetermined range of values.

11. The method of claim 10, wherein the predetermined range of values is a range centered around a value determined by a summation of the amount of structural deformation in the primary load path during an operative state and an amount of backlash required for triggering a locking key to engage the secondary load path.

12. The method of claim 10, wherein annunciating the failure includes locking the actuator.

13. The method of claim 12, further comprising:

notifying an automatic control unit of the failure so that the actuator remains locked if the automatic control unit initiates control of a system including the actuator after the actuator has been locked.

14. The method of claim 10, wherein the one or more sensors include one set of upper load path sensors or lower load path sensors to monitor respective upper or lower system components.

15. The method of claim 14 further comprising:

excluding a signal from an individual sensor in the set of sensors when the signal from the individual sensor indicates a relative displacement greater than the predetermined range of values.

16. The method of claim 14, further comprising:

locking the actuator when signals from two or more individual sensors of the set of sensors indicate a relative displacement greater than the predetermined range of values.

17. The method of claim 14, wherein the one or more sensors include the other set of upper load path sensors or lower load path sensors.