Boom deploy system

• US 6,779,758 B2
• Filed: 05/06/2003
• Issued: 08/24/2004
• Est. Priority Date: 05/07/2002
• Status: Expired due to Fees

• Current Assignee: Whippany Actuation Systems LLC (Transdigm Group Incorporated)
• Original Assignee: Smiths Aerospace, Inc. (Smiths Group International Holdings Ltd.)
• Inventors: Barba, Valentin G., Vu, Khoi T.
• Primary Examiner(s): ELDRED, JOHN W
• Application Number:
  US10/431,024
• Publication Number:
  US 20030218097A1
• Time in Patent Office: 476 Days
• Field of Search: 244/135.A, 244/135.R
• US Class Current: 244/135.00A
• CPC Class Codes: B64D 39/00 Refuelling during flight filling or emptying fuel tanks B64D37/14
• CPC Class Codes: B64D 39/02 Means for paying-in or out hose

Abstract

A boom deploy actuator with improved maintainability and simplicity has an electric motor and control circuitry for selectively powering the motor to develop torque with either rotational direction for rotating a capstan to vary the length of a boom cord extending from the capstan to a boom. In a preferred embodiment, the motor is a brushless electric motor. The control circuitry preferably includes circuit components for limiting the speed of the motor.

Claims

1. A method for deploying a tanker boom comprising:

developing a deploy starting torque having a first rotational direction using a boom deploy actuator for rotating a capstan to move the boom from a stowed position toward a fully deployed position;

developing a slack remover torque having a second rotational direction opposite the first rotational direction using the boom deploy actuator for rotating the capstan to remove any slack in a boom cord extending from the capstan to the boom;

developing a stow operation torque having the second rotational direction using the boom deploy actuator for rotating the capstan to move the boom from its fully deployed position to its stowed position.

2. The method as defined in claim 1, further comprising:

developing a damping torque having the second rotational direction using the boom deploy actuator for rotating the capstan to provide smooth deployment of the boom.

3. The method as defined in claim 2, wherein developing the damping torque comprises:

sensing a rotational speed of an actuator motor;

sensing a first current supplied to the motor; and

reducing the first current when one condition from the group consisting of the following is true;

     1) the rotational speed is higher than a maximum speed and

     2) the first current is higher than a maximum current.

4. The method as defined in claim 3, wherein developing the damping torque further comprises:

shunting a second current generated by the motor into a damper circuit to place an electrical load on the motor if the rotational speed is higher than the maximum speed.

5. The method as defined in claim 3, wherein sensing the rotational speed of the motor comprises measuring a frequency of a Hall effect sensor signal.

6. The method as defined in claim 3, wherein sensing the rotational speed of the motor comprises measuring a back electro-motive force generated by the motor.

7. The method as defined in claim 3, wherein reducing the first current comprises reducing a voltage supplied to the motor.

8. The method as defined in claim 3, wherein reducing the first current comprises pulse-width-modulating a power signal supplied to the motor.

9. The method as defined in claim 1, further comprising:

controlling a rotational velocity of the boom deploy actuator.

10. The method as defined in claim 9, wherein controlling the rotational velocity of the boom deploy actuator comprises:

sensing a rotational speed of an actuator motor;

sensing a first current supplied to the motor; and

reducing the first current when one condition from the group consisting of the following is true;

     1) the rotational speed is higher than a maximum speed and

     2) the first current is higher than a maximum current.

11. The method defined in claim 10, wherein controlling the rotational velocity of the boom deploy actuator further comprises:

shunting a second current generated by the motor into a damper circuit to place an electrical load on the motor if the first current is substantially zero and the rotational speed is higher than the maximum speed.

12. The method as defined in claim 10, wherein sensing the rotational speed of the motor comprises measuring a frequency of a Hall effect sensor signal.

13. The method as defined in claim 10, wherein sensing the rotational speed of the motor comprises measuring a back electro-motive force generated by the motor.

14. The method as defined in claim 10, wherein reducing the first current comprises reducing a voltage supplied to the motor.

15. The method as defined in claim 10, wherein reducing the first current comprises pulse-width-modulating a power signal supplied to the motor.

16. The method as defined in claim 1, wherein developing the deploy starting torque further comprises:

providing a signal to a lock/unlock actuator for unlocking the boom in its stowed position;

switching a first switch for providing power to the boom deploy actuator; and

supplying a first current to an actuator motor using a control block.

17. The method as defined in claim 16, wherein the first current is dependent upon the weight of the boom.

18. The method as defined in claim 16, wherein developing the slack remover torque further comprises:

supplying a second current to the actuator motor using the control block.

19. The method as defined in claim 18, wherein the second current is dependent upon the weight of the boom cord.

20. The method as defined in claim 18, wherein developing the stow operation torque further comprises:

switching a second switch for providing power to stow operation circuitry; and

supplying a third current to the actuator motor using the stow operation circuitry.

21. The method as defined in claim 20, wherein the third current is dependent upon the weight of the boom and the weight of the boom cord.

22. A boom deploy actuator comprising:

an electric motor coupled to a capstan for rotating the capstan in either rotational direction, wherein the length of a boom cord extending from the capstan to a boom varies with the rotation of the capstan; and

control circuitry for selectively powering the motor to develop torque with either rotational direction.

23. The boom deploy actuator as defined in claim 22, wherein the electric motor is an electric brushless motor.

24. The boom deploy actuator as defined in claim 22, wherein the control circuitry comprises circuit components for limiting the speed of the motor.

25. The boom deploy actuator as defined in claim 24, wherein the circuit components for limiting the speed of the motor comprise:

damper circuitry for selectively applying electrical current generated by the motor to an electrical load to thereby retard the motor.

26. The boom deploy actuator as defined in claim 25, wherein the circuit components for limiting the speed of the motor further comprise:

hall effect sensors for measuring the rotational speed of the motor.

27. The boom deploy actuator as defined in claim 22 further comprising:

first circuitry for selectively commanding the control circuitry to power the motor to develop a first torque with a first rotational direction for urging the boom to move in a predetermined one of its linear directions.

28. The boom deploy actuator as defined in claim 27, wherein the first torque is a boom deploying torque.

29. The boom deploy actuator as defined in claim 27, wherein the first circuitry comprises:

circuit components for selectively commanding the control circuitry to power the motor to develop a second torque with a second rotational direction for removing slack from the boom cord.

30. The boom deploy actuator as defined in claim 29 further comprising:

damper circuitry for selectively effecting the motor to develop a third torque with the second rotational direction for limiting the rotational speed of the capstan.

31. The boom deploy actuator as defined in claim 30, wherein the third torque is a damping torque.

32. The boom deploy actuator as defined in claim 30 further comprising:

torque setting circuitry for selectively commanding the control circuitry to power the motor to develop a fourth torque with the second rotational direction for urging the boom to move in the other predetermined one of its linear directions.

33. The boom deploy actuator as defined in claim 32, wherein the fourth torque is a stow operation torque.

34. A system for providing improved maintainability in the boom deploy actuator as defined in claim 22 comprising apparatus for:

locking and unlocking the boom in a stowed position; and

powering the boom deploy actuator when the boom is not locked by the locking and unlocking apparatus.

35. A system for providing improved maintainability in an aircraft boom deploy actuator comprising apparatus for:

locking and unlocking a boom in a stowed position;

powering the boom deploy actuator when the boom is not locked by the locking and unlocking apparatus; and

controlling a rotational velocity of the actuator.

36. A system for providing improved maintainability in an aircraft boom deploy actuator comprising apparatus for:

locking and unlocking a boom in a stowed position;

powering the boom deploy actuator when the boom is not locked by the locking and unlocking apparatus; and

controlling a rotational velocity of the actuator, wherein the apparatus for controlling the rotational velocity of the actuator comprises apparatus for;

sensing a rotational speed of an actuator motor;

sensing a first current supplied to the motor; and

reducing the first current when one condition from the group consisting of the following is true;

     1) the rotational velocity is higher than a first speed and

     2) the first current is higher than a first threshold current.

37. The system as defined in claim 36, wherein the apparatus for controlling the rotational velocity of the actuator further comprises apparatus for:

shunting a second current generated by the motor into a damper circuit to place an electrical load on the motor if the rotational speed is higher than the maximum speed.

38. The system as defined in claim 36, wherein the apparatus for sensing the rotational speed of the motor comprises apparatus for:

measuring a frequency of a Hall effect sensor signal.

39. The system as defined in claim 36, wherein the apparatus for sensing the rotational speed of the motor comprises apparatus for:

measuring a back electro-motive force generated by the motor.

40. The system as defined in claim 36, wherein the apparatus for reducing the first current comprises apparatus for:

reducing a voltage supplied to the motor.

41. The system as defined in claim 36, wherein the apparatus for reducing the first current comprises apparatus for:

pulse-width-modulating a power signal supplied to the motor.

42. A system for providing improved maintainability in an aircraft boom deploy actuator comprising apparatus for:

locking and unlocking a boom in a stowed position;

powering the boom deploy actuator when the boom is not locked by the locking and unlocking apparatus; and

controlling a rotational velocity of the actuator, wherein the apparatus for controlling the rotational velocity of the actuator comprises apparatus for;

powering a brushless electric motor to rotate a capstan in either rotational direction, wherein the length of a boom cord extending from the capstan to the boom varies with the rotation of the capstan; and

commanding the apparatus for powering the motor to power the motor to rotate in a first rotational direction for urging the boom to move in a predetermined one of its linear directions.

43. The system as defined in claim 42, wherein the apparatus for commanding further comprises apparatus for:

selectively commanding the apparatus for powering the motor to power the motor to rotate in a second rotational direction for removing slack from a boom cord extending from the capstan to the boom.

44. The system as defined in claim 43 further comprising apparatus for:

selectively commanding the apparatus for powering the motor to power the motor to rotate in the second rotational direction for urging the boom to move in the other predetermined one of its linear directions.