PLANETARY DE-ROTATION SYSTEM FOR A SHAFT FAIRING SYSTEM

• US 20100270423A1
• Filed: 01/02/2008
• Published: 10/28/2010
• Est. Priority Date: 01/02/2008
• Status: Active Grant

• Current Assignee: Sikorsky Aircraft Corporation (Martin Marietta Corporation)
• Original Assignee: Sikorsky Aircraft Corporation (Martin Marietta Corporation)
• Inventors: Lauder, Timothy Fred
• Granted Patent: US 8,534,596 B2
• Time in Patent Office: Days
• US Class Current: 244/17.190
• CPC Class Codes: B64C 1/00 Fuselages; Constructional features common to fuselages, wings, stabilising surfaces or the like
• CPC Class Codes: B64C 27/04 Helicopters
• CPC Class Codes: B64C 27/10 arranged coaxially
• CPC Class Codes: B64C 27/12 Rotor drives
• CPC Class Codes: B64C 27/14 Direct drive between power plant and rotor hub
• CPC Class Codes: B64C 27/20 Rotorcraft characterised by having shrouded rotors, e.g. flying platforms
• CPC Class Codes: B64C 7/00 Structures or fairings not otherwise provided for

Abstract

A de-rotation system includes a planetary gear set, and a fairing support structure mounted for rotation with a first ring gear.

Claims

1. A de-rotation system comprising:

a first ring gear defined about an axis;

a second ring gear defined about said axis;

a planetary gear set in meshing engagement with said first ring gear and said second ring gear;

a cage assembly which supports said planetary gear set; and

a support structure mounted for rotation with said first ring gear.

2. The system as recited in claim 1, wherein said second ring gear is fixed relative to said axis.

3. The system as recited in claim 1, wherein said planetary gear set is in meshing engagement with an inner diameter of said first ring gear and an inner diameter of said second ring gear.

4. The system as recited in claim 1, wherein said planetary gear set comprises a multitude of planet gear assemblies.

5. The system as recited in claim 4, wherein each of said multitude of planet gear assemblies comprise an upper planet gear, a lower planet gear and a shaft that rotationally connects said upper planet gear and said lower planet gear.

6. The system as recited in claim 1, further comprising a drive system which selectively rotates said second ring gear.

7. The system as recited in claim 6, further comprising a control system in communication with said drive system to selectively rotate said second ring gear to azimuthally position said second ring gear in response to a flight control system.

8. A fairing system comprising:

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

a planetary gear set configured to control a position of said shaft fairing about said axis of rotation.

9. The system as recited in claim 8, further comprising:

an upper hub fairing defined about said axis; and

a lower hub fairing defined about said axis,

wherein said shaft fairing is mounted for relative rotation between said upper hub fairing and said lower hub fairing.

10. The system as recited in claim 8, wherein said planetary gear set further comprises:

a first ring gear defined about said axis;

a second ring gear defined about said axis;

a planetary gear set in meshing engagement with said first ring gear and said second ring gear;

a cage assembly which supports said planetary gear set; and

a fairing support structure mounted for rotation with said first ring gear and said shaft fairing.

11. The system as recited in claim 10, further comprising a drive system which selectively rotates said second ring gear.

12. The system as recited in claim 11, further comprising a control system in communication with said drive system to selectively rotate said second ring gear to azimuthally position said second ring gear in response to a flight control system.

13. The system as recited in claim 10, wherein said second ring gear is fixed relative to said axis.

14. A coaxial rotor system comprising:

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

an upper rotor hub mounted to an upper rotor shaft which is 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 axis of rotation;

a planetary gear set configured to control a position of said shaft fairing about said axis of rotation.

15. The system as recited in claim 14, wherein said planetary gear set further comprises:

a first ring gear defined about said axis;

a second ring gear defined about said axis;

a planet gear assembly in meshing engagement with said first ring gear and said second ring gear;

a cage assembly which supports said planet gear assembly; and

a fairing support structure mounted for rotation with said first ring gear and said shaft fairing.

16. The system as recited in claim 15, further comprising a drive system which selectively rotates said second ring gear.

17. The system as recited in claim 16, further comprising a control system in communication with said drive system to selectively rotate said second ring gear to azimuthally position said second ring gear in response to a flight control system.

18. The system as recited in claim 15, wherein said second ring gear is fixed relative to said axis.

19. The system as recited in claim 15, wherein said cage assembly rotates with said lower rotor hub.

20. 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 axis of rotation;

a planetary gear set configured to control a position of said shaft fairing about said axis of rotation.

21. The aircraft as recited in claim 20, wherein said aircraft is a helicopter.