Method for monitoring a no-back device of an adjustable horizontal trim actuator, corresponding system and aircraft

• US 20110127375A1
• Filed: 09/23/2010
• Published: 06/02/2011
• Est. Priority Date: 11/27/2009
• Status: Active Grant

• Current Assignee: Airbus Operations (European Aeronautic Defence and Space Company EADS NV)
• Original Assignee: Airbus Operations (European Aeronautic Defence and Space Company EADS NV)
• Inventors: Ferreol, Ivan, TALLOT, Cédric, Baxerres, Laura
• Granted Patent: US 8,918,291 B2
• Time in Patent Office: Days
• US Class Current: 244/99.9
• CPC Class Codes: B64C 13/24 Transmitting means
• CPC Class Codes: B64C 5/10 adjustable
• CPC Class Codes: B64D 2045/0085 Devices for aircraft health monitoring, e.g. monitoring flutter or vibration
• CPC Class Codes: B64D 45/00 Aircraft indicators or protectors not otherwise provided for camouflage F41H3/00
• CPC Class Codes: F16H 25/2021 with means for avoiding overloading

Abstract

The present invention relates to a method and a system for monitoring of an actuator equipped with a no-back device or no-back brake and in particular an adjustable horizontal trim actuator provided in aircraft.

The method comprises the steps consisting in:

determining a value representative of the mechanical work produced by the said actuator;

comparing the said determined value with ranges of values so as to detect a dysfunctioning of the said no-back device.

In the case of an actuator of screw/nut type and a hydraulic motor, the said value representative of the mechanical work is determined from an algebraic velocity of the motor and an algebraic differential of hydraulic pressure at the terminals of the said motor.

A negative value corresponding to negative mechanical work then identifies a failure of the no-back device.

Claims

1. A method for monitoring of an actuator equipped with a no-back device, comprising the steps consisting in:

determining a value representative of the mechanical work produced by the said actuator;

comparing the said determined value with ranges of values so as to detect dysfunctioning of the said no-back device.

2. A method according to the preceding claim, wherein the said actuator comprises a screw/nut assembly driven by a motor, and the said determination of a value representative of the mechanical work comprises the measurement of at least one physical value relating to the said motor.

3. A method according to the preceding claim, wherein the actuator has a hydraulic channel, and the said value representative of the mechanical work is determined from an algebraic velocity of the said motor and an algebraic differential of hydraulic pressure at the terminals of the said motor.

4. A method according to the preceding claim, wherein the dysfunctioning of the said no-back device is detected when the said value representative of the mechanical work is of given sign, and the said algebraic hydraulic pressure differential and algebraic velocity each has an absolute value greater than a corresponding threshold value.

5. A method according to claim 1, wherein the detection of dysfunctioning is temporarily inhibited as a function of a parameter relating to reversal of the direction of movement of the said actuator.

6. A method according to claim 1, wherein the detection of dysfunctioning is temporarily inhibited as a function of a parameter representative of a rate of deceleration of the said motor.

7. A method according to claim 1, wherein the detection of dysfunctioning is a function of the algebraic sign of the said value representative of the determined mechanical work.

8. A method according to claim 1, comprising a step of indicating a dysfunctioning of the said no-back device when a dysfunctioning of the said no-back device is detected for several said consecutive determined values.

9. A system for monitoring an actuator equipped with a no-back device, comprising:

a determination module for determining a value representative of the mechanical work produced by the said actuator;

a comparison module for comparing the said determined value with ranges of values so as to detect a dysfunctioning of the said no-back device.

10. A monitoring system according to the preceding claim, wherein the said actuator comprises a screw/nut assembly driven by a motor, and the module for determining a value representative of the mechanical work is configured to measure at least one physical value relating to the said motor.

11. A monitoring system according to the preceding claim, wherein the actuator has a hydraulic channel, and the determination module is configured to determine the said value representative of the mechanical work from an algebraic velocity of the said motor and an algebraic differential of hydraulic pressure at the terminals of the said motor.

12. A monitoring system according to the preceding claim, configured to detect dysfunctioning of the said no-back device when the said value representative of the mechanical work is of given sign, and the said algebraic hydraulic pressure differential and algebraic velocity each has an absolute value greater than a corresponding threshold value.

13. A monitoring system according to claim 9, configured to inhibit the detection of dysfunctioning temporarily as a function of a parameter relating to reversal of the direction of movement of the said actuator.

14. A monitoring system according to claim 9, configured to inhibit the detection of dysfunctioning temporarily as a function of a parameter representative of a rate of deceleration of the said motor.

15. A monitoring system according to claim 9, wherein the comparison module is configured to detect dysfunctioning as a function of the algebraic sign of the said value representative of the mechanical work determined.

16. A monitoring system according to claim 9, comprising an indicating means configured to indicate a dysfunctioning of the said no-back device when a dysfunctioning of the said no-back device is detected for several said consecutive determined values.

17. An aircraft comprising an actuator equipped with a no-back device and a system for monitoring the said actuator according to claim 9.