MAGNETIC DE-ROTATION SYSTEM FOR A SHAFT FAIRING SYSTEM

• US 20100264258A1
• Filed: 12/03/2007
• Published: 10/21/2010
• Est. Priority Date: 12/03/2007
• Status: Active Grant

• Current Assignee: Sikorsky Aircraft Corporation (Martin Marietta Corporation)
• Original Assignee: Sikorsky Aircraft Corporation (Martin Marietta Corporation)
• Inventors: Sirohi, Jayant, Lauder, Timothy Fred
• Granted Patent: US 8,584,983 B2
• Time in Patent Office: Days
• US Class Current: 244/17.270
• CPC Class Codes: B64C 2027/8236 including pusher propellers
• CPC Class Codes: B64C 27/04 Helicopters
• CPC Class Codes: B64C 27/10 arranged coaxially
• CPC Class Codes: B64C 27/82 characterised by the provision of an auxiliary rotor or fluid-jet device for counter-balancing lifting rotor torque or changing direction of rotorcraft

Abstract

A magnetic de-rotation system includes an inner ring which supports an eddy current ring and at least one inner ring magnet and an outer ring which supports at least one outer ring magnet, attraction between the at least one inner ring magnet and the at least one outer ring magnet produces a stable rotational position for a fairing.

Claims

1. A de-rotation system comprising:

a fairing;

an inner ring which supports an eddy current ring and at least one inner ring magnet, said eddy current ring extends for a first axial length of said inner ring while said at least one inner ring magnet extends for a second axial length of said inner ring; and

an outer ring which supports at least one outer ring magnet, said at least one outer ring magnet extends for a third axial length of said outer ring such that said at least one outer ring magnet axially extends between said first axial length and said second axial length, attraction between said at least one inner ring magnet and said at least one outer ring magnet produces a stable rotational position.

2. The system as recited in claim 1, wherein said at least one inner ring magnet includes a multiple of inner ring magnets equally spaced about the circumference of said inner ring and said at least one outer ring magnet includes a multiple of outer ring magnets greater in number than said multiple of inner ring magnets.

3. The system as recited in claim 1, wherein said inner ring is eccentric to said outer ring.

4. A fairing system comprising:

a shaft fairing mounted for rotation about an axis of rotation; and

a magnetic de-rotation system mounted to said shaft fairing to control a rotation of said shaft fairing about said axis of rotation.

5. The system as recited in claim 4, further comprising:

an upper hub fairing defined about said axis; and

a lower hub fairing defined about said axis, said shaft fairing mounted for relative rotation between said upper hub fairing and said lower hub fairing.

6. The system as recited in claim 4, wherein said magnetic de-rotation system further comprises:

an upper magnetic ring assembly affixed to said shaft fairing; and

a lower magnetic ring assembly affixed to said shaft fairing.

7. The system as recited in claim 6, wherein said magnetic de-rotation system further comprises:

each of said upper magnetic ring assembly and said lower magnetic ring assembly comprises an inner ring which supports at least one inner ring magnet and an outer ring which supports at least one outer ring magnet, attraction between said at least one inner ring magnet and said at least one outer ring magnet produces at least one stable rotational position.

8. The system as recited in claim 7, wherein said inner ring is eccentric to said outer ring.

9. The system as recited in claim 7, wherein said inner ring comprises an eddy current ring and said at least one inner ring magnet.

10. The system as recited in claim 9, wherein said eddy current ring extends for a first axial length along said axis of rotation of said inner ring while said at least one inner ring magnet extends for a second axial length along said axis of rotation of said inner ring

11. The system as recited in claim 10, wherein said outer ring comprises at least one outer ring magnet which extends for a third axial length of said outer ring.

12. The system as recited in claim 11, wherein said third axial length is approximately equal to said first axial length plus said second axial length.

13. The system as recited in claim 11, wherein said third axial length is greater than said first axial length.

14. The system as recited in claim 11, wherein said third axial length is greater than said second axial length.

15. The system as recited in claim 9, wherein said at least one inner ring magnet includes a multiple of inner ring magnets equally spaced about the circumference of said inner ring.

16. The system as recited in claim 15, wherein said outer ring comprises a multiple of outer ring magnets, said multiple of outer ring magnets greater in number than said multiple of inner ring magnets, at least one of said multiple of outer ring magnets being of an opposite polarity of at least one of said multiple of inner ring magnets.

17. A counter rotating coaxial rotor system comprising:

a lower rotor hub mounted to a lower rotor shaft and configured to rotate about an axis of rotation;

an upper rotor hub mounted to an upper rotor shaft and configured to rotate about said axis of rotation, said upper rotor shaft mounted through said lower rotor shaft and rotating in a direction opposite a direction of rotation of the lower rotor shaft

an upper hub fairing mounted at least partially about said upper rotor hub;

a lower hub fairing mounted at least partially about said lower rotor hub;

a shaft fairing mounted between said upper hub fairing and said lower hub fairing for rotation about said rotor axis of rotation;

an upper magnetic ring assembly affixed to said upper rotor shaft and said shaft fairing; and

a lower magnetic ring assembly affixed to said lower rotor shaft and said shaft fairing.

18. The system as recited in claim 17, wherein said upper magnetic ring assembly and said lower magnetic ring assembly each comprises:

an inner ring which supports at least one inner ring magnet and an outer ring which supports at least one outer ring magnet, attraction between said at least one inner ring magnet and said at least one outer ring magnet produces a stable rotational position.

19. The system as recited in claim 17, wherein said inner ring is eccentric to said outer ring.

20. The system as recited in claim 17, wherein said inner ring comprises an eddy current ring and said at least one inner ring magnet.

21. The system as recited in claim 20, wherein said eddy current ring extends for a first axial length of said inner ring while said at least one inner ring magnet extends for a second axial length of said inner ring

22. The system as recited in claim 21, wherein said outer ring comprises at least one outer ring magnet which extends for a third axial length of said outer ring, said third axial length.

23. An aircraft comprising:

a lower rotor hub mounted to a lower rotor shaft and configured to rotate about an axis of rotation;

an upper rotor hub mounted to an upper rotor shaft and configured to rotate about said axis of rotation, said upper rotor shaft mounted through said lower rotor shaft and rotating in a direction opposite a direction of rotation of the lower rotor shaft

an upper hub fairing mounted at least partially about said upper rotor hub;

a lower hub fairing mounted at least partially about said lower rotor hub;

a shaft fairing mounted between said upper hub fairing and said lower hub fairing for rotation about said rotor axis of rotation;

an upper magnetic ring assembly affixed to said upper rotor shaft and said shaft fairing; and

a lower magnetic ring assembly affixed to said lower rotor shaft and said shaft fairing.

24. The aircraft as recited in claim 23, wherein said aircraft is a helicopter.