ROTATING PROPROTOR ARRANGEMENT FOR A TILTROTOR AIRCRAFT

• US 20180079503A1
• Filed: 09/21/2016
• Published: 03/22/2018
• Est. Priority Date: 09/21/2016
• Status: Active Grant

• Current Assignee: Textron Innovations Incorporated (Textron Inc)
• Original Assignee: Bell Helicopter Textron Incorporated (Textron Inc)
• Inventors: Ivans, Steven Ray, Ross, Brent Chadwick
• Granted Patent: US 10,279,901 B2
• Time in Patent Office: Days
• CPC Class Codes: B64C 29/0033 the propellers being tiltable relative to the fuselage
• CPC Class Codes: B64C 3/18 Spars; Ribs; Stringers
• CPC Class Codes: B64D 27/02 Aircraft characterised by the type or position of power plants fuselages specially adapted for mounting power plants B64C1/16; wings specially adapted for power plants B64C3/32
• CPC Class Codes: B64D 33/02 of combustion air intakes air intakes for gas-turbine plants or jet-propulsion plants per se F02C7/04; air intakes for combustion engines in general F02M35/00
• CPC Class Codes: B64D 33/04 of exhaust outlets or jet pipes exhaust outlets for combustion engines in general F01N; jet pipes or nozzles for jet-propulsion plants per se F02K; plants characterised by the form or arrangement of the jet pipe or nozzle F02K ; attitude, flight direction, or altitude control by jet reaction B64C
• CPC Class Codes: B64D 35/04 characterised by the transmission driving a plurality of propellers or rotors
• CPC Class Codes: B64D 35/08 characterised by the transmission being driven by a plurality of power plants
• CPC Class Codes: B64U 30/10 Wings
• CPC Class Codes: B64U 30/20 Rotors; Rotor supports
• CPC Class Codes: B64U 50/13 using external fans or propellers
• CPC Class Codes: F16H 1/203 with non-parallel axes F16H1/22 takes precedence
• CPC Class Codes: F16H 35/008 for variation of rotational phase relationship, e.g. angular relationship between input and output shaft couplings F16D3/10

Abstract

A propulsion system includes an engine disposed within a fuselage, a first gearbox coupled to the engine, a wing member having an upper wing skin and torque box formed by a first rib, a second rib, a first spar and second spar, a drive shaft coupled to the first gearbox and disposed within the wing member, a second gear box coupled to the drive shaft and disposed outboard from the second rib or inboard from the first rib, and a rotatable proprotor coupled to the second gear box. The rotatable proprotor includes a plurality of rotor blades, a rotor mast having a mast axis of rotation, and a proprotor gearbox coupled to the rotor mast. The proprotor gearbox is rotatable about a conversion axis, which intersects with the mast axis of rotation at a point within a central region of the torque box and above the upper wing skin.

Claims

1. A propulsion system for a tiltrotor aircraft, the propulsion system comprising:

an engine disposed within a fuselage;

a first gearbox coupled to the engine;

a wing member having a first rib, a second rib, a first spar, second spar and an upper wing skin, wherein the first rib, the second rib, the first spar and the second spar are coupled together to form a torque box;

a drive shaft mechanically coupled to the first gearbox and disposed within the wing member;

a second gear box coupled to the drive shaft and disposed either outboard from the second rib or inboard from the first rib;

a rotatable proprotor mechanically coupled to the second gear box, the rotatable proprotor comprising;

a plurality of rotor blades;

a rotor mast having a rotor mast axis of rotation; and

a proprotor gearbox coupled to the rotor mast, the proprotor gearbox being rotatable about a conversion axis, the conversion axis and the rotor mast axis of rotation intersecting at an intersection point, the intersection point being located in a central region within the torque box and above an airfoil surface profile of the upper wing skin.

2. The propulsion system as recited in claim 1, wherein the engine is disposed forward of the wing member, under the wing member or aft of the wing member.

3. The propulsion system as recited in claim 1, wherein the engine comprises two engines.

4. The propulsion system as recited in claim 1, further comprising an exhaust connected to the engine and extending to an upper portion of the fuselage aft of the wing member.

5. The propulsion system as recited in claim 1, further comprising an exhaust connected to the engine and extending to either side of the fuselage aft of the wing member.

6. The propulsion system as recited in claim 1, further comprising an inlet connected to the engine and blended into each side of the fuselage.

7. The propulsion system as recited in claim 1, further comprising an inlet connected to the engine and blended into a forward facing upper surface of the fuselage.

8. The propulsion system as recited in claim 1, wherein the conversion axis is parallel to a lengthwise axis of the wing member.

9. The propulsion system as recited in claim 1, further comprising:

a direction change gearbox coupled to the engine; and

a riser shaft coupled to the direction change gearbox and the first gearbox.

10. The propulsion system as recited to claim 1, wherein the first gearbox comprises a single spiral bevel gear or a dual spiral bevel gear.

11. The propulsion system as recited in claim 1, wherein:

the second gearbox comprises an interconnect gearbox; and

the proprotor gearbox comprises a single spiral bevel gear, or a quill shaft and a spindle gearbox.

12. The propulsion system as recited in claim 1, further comprising:

an outboard housing;

an inboard housing; and

wherein an outboard portion of the proprotor gearbox is rotatably coupled to the outboard housing, and the inboard portion of the proprotor gearbox is rotatably coupled to the inboard housing.

13. The propulsion system as recited in claim 12, wherein the inboard housing and the outboard housing are structurally located above the upper wing skin of the wing member.

14. The propulsion system as recited in claim 1, wherein the tiltrotor aircraft comprises an unmanned aerial vehicle.

15. A tiltrotor aircraft, comprising:

a fuselage;

an engine disposed within the fuselage;

a first gearbox coupled to the engine;

a wing member having a first rib, a second rib, a first spar, second spar and an upper wing skin, wherein the first rib, the second rib, the first spar and the second spar are coupled together to form a torque box;

a drive shaft mechanically coupled to the first gearbox and disposed within the wing member;

a second gear box coupled to the drive shaft and disposed either outboard from the second rib or inboard from the first rib;

a rotatable proprotor mechanically coupled to the second gear box, the rotatable proprotor comprising;

a plurality of rotor blades;

a rotor mast having a rotor mast axis of rotation; and

a proprotor gearbox coupled to the rotor mast, the proprotor gearbox being rotatable about a conversion axis, the conversion axis and the rotor mast axis of rotation intersecting at an intersection point, the intersection point being located in a central region within the torque box and above an airfoil surface profile of the upper wing skin.

16. The tiltrotor aircraft as recited in claim 15, wherein the engine is disposed forward of the wing member, under the wing member or aft of the wing member.

17. The tiltrotor aircraft as recited in claim 15, wherein the engine comprises two engines.

18. The tiltrotor aircraft as recited in claim 15, further comprising an exhaust connected to the engine and extending to an upper portion of the fuselage aft of the wing member.

19. The tiltrotor aircraft as recited in claim 15, further comprising an exhaust connected to the engine and extending to either side of the fuselage aft of the wing member.

20. The tiltrotor aircraft as recited in claim 15, further comprising an inlet connected to the engine and blended into each side of the fuselage.

21. The tiltrotor aircraft as recited in claim 15, further comprising an inlet connected to the engine and blended into a forward facing upper surface of the fuselage.

22. The tiltrotor aircraft as recited in claim 15, wherein the conversion axis is parallel to a lengthwise axis of the wing member.

23. The tiltrotor aircraft as recited in claim 15, further comprising:

a direction change gearbox coupled to the engine; and

a riser shaft coupled to the direction change gearbox and the first gearbox.

24. The tiltrotor aircraft as recited to claim 15, wherein the first gearbox comprises a single spiral bevel gear or a dual spiral bevel gear.

25. The tiltrotor aircraft as recited in claim 15, wherein:

the second gearbox comprises an interconnect gearbox; and

the proprotor gearbox comprises a single spiral bevel gear, or a quill shaft and a spindle gearbox.

26. The tiltrotor aircraft as recited in claim 15, further comprising:

an outboard housing;

an inboard housing; and

wherein an outboard portion of the proprotor gearbox is rotatably coupled to the outboard housing, and the inboard portion of the proprotor gearbox is rotatably coupled to the inboard housing.

27. The tiltrotor aircraft as recited in claim 26, wherein the inboard housing and the outboard housing are structurally located above the upper wing skin of the wing member.

28. The tiltrotor aircraft as recited in claim 15, further comprising a wing extension extending outboard from the rotatable proprotor.

29. The tiltrotor aircraft as recited in claim 28, wherein the wing extension includes a straight portion and an upwardly canted portion.

30. The tiltrotor aircraft as recited in claim 28, wherein the wing extension is rotatable or foldable.

31. The tiltrotor aircraft as recited in claim 15, wherein the tiltrotor aircraft comprises an unmanned aerial vehicle.