Single piece co-cure composite wing

• US 20060249626A1
• Filed: 09/23/2005
• Published: 11/09/2006
• Est. Priority Date: 11/18/1999
• Status: Active Grant

• Current Assignee: General Atomics Aeronautical Systems Incorporated (General Atomic Technologies Corporation)
• Original Assignee: Rocky Mountain Composites, Inc.
• Inventors: Ashton, Larry J., Simpson, Craig B., Tuttle, Steven T., Allman, Mike G.
• Granted Patent: US 7,681,835 B2
• Time in Patent Office: Days
• US Class Current: 244/123.100
• CPC Class Codes: B64C 3/20 Integral or sandwich constructions
• CPC Class Codes: Y10T 428/24107 including mechanically interengaged strands, strand-portions or strand-like strips
• CPC Class Codes: Y10T 428/24124 Fibers
• CPC Class Codes: Y10T 428/24612 Composite web or sheet

Abstract

A single piece co-cured composite wing is disclosed. The wing has a flying surface and structural members. In one embodiment the structural members may be a plurality of spars. The spars may have various shapes to increase the buckling strength. The spars may be wave shaped, such as a sinusoidal shape. The flying surface and the structural members are co-cured in order to form a single piece, integral wing structure. A process for manufacturing a single piece co-cured wing is also disclosed. The process may include laying out composite sheets for the flying surface of the wing. Then, the composite material of the spars is arranged around a plurality of pressurizable forms. Finally, the composite material is cured in a clamshell frame. A single piece co-cured composite structure is also disclosed that includes an outer skin, and inner skin, a frame, and a stringer.

Claims

26. A composite wing structure comprising:

a composite flying surface defining a leading edge and a trailing edge; and

a plurality of spars extending lengthwise along the flying surface to structurally support the flying surface, wherein each of the spars comprises an I-shaped cross sectional shape having fibers substantially uncommingled with fibers of any of the other spars or with fibers of the flying surface, wherein the spars are integrally formed with the flying surface via co-curing of the spars and flying surface.

28. The apparatus, as recited in claim 26, wherein each spar cap is comprised of filament bands orientated generally parallel from the flying surface.

30. The apparatus, as recited in claim 28, wherein each webbing is comprised of filament bands orientated about 45°

relative to the length of the spar.

40. A co-cured composite wing structure comprising:

a composite flying surface having an inner skin and an outer skin; and

a plurality of spars extending lengthwise along the flying surface to structurally support the flying surface, wherein the spars extend inward from the outer skin through the inner skin and are interwoven with the flying surface, wherein the spars are integrally formed with the flying surface via co-curing of the spars and flying surface.

1. A single piece co-cured composite wing comprising:

a composite flying surface defining a leading edge and a trailing edge;

a composite wing box; and

composite structural members, wherein the flying surface, wing box, and the structural members form a single piece co-cured composite wing, wherein each of the composite flying surface and the composite structural members is constructed independent of any pre-formed composite components.

2. The apparatus, as recited in claim 1, wherein the structural member comprises at least one spar.

3. The apparatus, as recited in claim 2, wherein the spar has a spar cap.

4. The apparatus, as recited in claim 3, wherein the spar cap is comprised of filament bands orientated generally parallel to the flying surface.

5. The apparatus, as recited in claim 2, wherein the spar has a webbing.

6. The apparatus, as recited in claim 5, wherein the webbing is comprised of filament bands orientated about 45°

relative to the length of the spar.

7. The apparatus, as recited in claim 2, wherein the spar is comprised of two substantially C-shaped composite sections.

8. The apparatus, as recited in claim 7, wherein the C-shaped sections are positioned in opposing orientations to form an I-beam.

9. The apparatus, as recited in claim 2, wherein the spar has a substantially J-shaped cross-section.

10. The apparatus, as recited in claim 2, wherein the spar has a C-shaped cross-section.

11. The apparatus, as recited in claim 2, wherein the spar is sinusoidal shaped.

12. The apparatus, as recited in claim 2, wherein the spar comprises a plurality of alternating bends.

13. The apparatus, as recited in claim 12, wherein the alternating bends provide a varying frequency.

14. The apparatus, as recited in claim 12, wherein the alternating bends provide a varying amplitude.

15. The apparatus, as recited in claim 12, wherein the alternating bends provide a plurality of step waves.

16. The apparatus, as recited in claim 2, wherein the spar has a substantially flat section to allow attachment of intersecting structures.

17. The apparatus, as recited in claim 1, wherein the composite flying surface comprises an upper flying surface, the apparatus further comprising a lower flying surface.

18. The apparatus, as recited in claim 17, wherein the upper flying surface is substantially comprised of a first sheet of composite material and the lower flying surface is substantially comprised of a second sheet of composite material.

19. The apparatus, as recited in claim 18, wherein first sheet and the second sheet intersect at a location below a leading edge of the wing.

20. The apparatus, as recited in claim 1, wherein the composite structural member is a rib.

21. The apparatus, as recited in claim 1, wherein the wing structure is a complete wing span.

22. The apparatus, as recited in claim 21, wherein the complete wing span has a spar that is continuous through the complete wing span.

23. The apparatus, as recited in claim 1, wherein the flying surface further defines a wingtip.

24. The apparatus, as recited in claim 1, wherein the wing structure has strands of conductive material imbedded in the composite material.

25. The apparatus, as recited in claim 1, further comprising a layer of primer co-cured to the flying surface.

27. The apparatus, as recited in claim 25, wherein each spar has a spar cap.

29. The apparatus, as recited in claim 25, wherein each spar has a webbing.

31. The apparatus, as recited in claim 25, wherein each spar is comprised of two substantially C-shaped composite sections positioned in opposing orientations to form the I-shaped cross sectional shape.

32. The apparatus, as recited in claim 25, wherein the at least one spar is sinusoidal shaped.

33. The apparatus, as recited in claim 25, wherein the composite flying surface comprises an upper flying surface, the apparatus further comprising a lower flying surface.

34. The apparatus, as recited in claim 32, wherein the upper flying surface is substantially comprised of a first sheet of composite material and the lower flying surface is substantially comprised of a second sheet of composite material.

35. The apparatus, as recited in claim 33, wherein first sheet and the second sheet intersect at a location below a leading edge of the composite wing structure.

36. The apparatus, as recited in claim 25, wherein the composite wing structure is a complete wing span.

37. The apparatus, as recited in claim 35, wherein the complete wing span has a spar that is continuous through the complete wing span.

38. The apparatus, as recited in claim 25, wherein the composite wing structure is at least one of an aileron, a wing tip, a horizontal stabilizer, a vertical stabilizer, a flap, an elevator and a canard.

39. The apparatus, as recited in claim 25, further comprising a layer of primer co-cured to the flying surface.

41. The apparatus, as recited in claim 40, wherein each spar has a spar cap, the spar cap extending parallel to the outer skin and between the outer skin and the inner skin.

42. The apparatus, as recited in claim 40, wherein each spar has a webbing, wherein the inner skin extends partially onto the webbing.

43. The apparatus, as recited in claim 42, wherein the webbing is comprised of filament bands orientated about 45°

relative to the length of the spar.

44. The apparatus, as recited in claim 40, wherein at least one spar has an I-shaped cross sectional shape.

45. The apparatus, as recited in claim 40, wherein at least one spar has a C-shaped cross sectional shape.

46. The apparatus, as recited in claim 40, wherein at least one spar has a J-shaped cross sectional shape.

47. The apparatus, as recited in claim 46, wherein the complete wing span has a spar that is continuous through the complete wing span.

48. The apparatus, as recited in claim 40, wherein the composite wing structure is at least one of an aileron, a wing tip, a horizontal stabilizer, a vertical stabilizer, a flap, an elevator and a canard.

45-1. The apparatus, as recited in claim 40, wherein the at least one spar is sinusoidal shaped.

46-2. The apparatus, as recited in claim 40, wherein the composite wing structure is a complete wing span.

49. A single piece co-cured composite structure comprising:

a composite skin, the skin comprising an inner skin and an outer skin;

a composite frame having a length, the frame comprising a core of fibers, wherein the frame extends inward from the outer skin; and

a composite stringer having a length, the stringer comprising a core of fibers, wherein the stringer extends inward from the outer skin, wherein the fibers of the core of the frame is interwoven with the fibers of the core of the stringer, wherein the skin, the frame, and the stringer form a single piece co-cured composite structure.

50. The apparatus, as recited in claim 49, wherein the core of the frame comprises unidirectional fibers aligned along the length of the frame.

51. The apparatus, as recited in claim 49, wherein the core of the stringer comprises unidirectional fibers aligned along the length of the stringer.

52. The apparatus, as recited in claim 49, wherein the fibers of the frame and stringer are woven together in successive layers.

53. The apparatus, as recited in claim 49, wherein the frame extends through the inner skin.

54. The apparatus, as recited in claim 49, wherein the stringer extends through the inner skin.

55. The apparatus, as recited in claim 49, wherein the frame comprises a frame base, wherein the frame base is interwoven with the skin.

56. The apparatus, as recited in claim 49, wherein the stringer comprises a stringer base, wherein the stringer base is interwoven with the skin.

57. The apparatus, as recited in claim 49, wherein the frame comprises a frame shear-ply that extends partially around the core of the frame.

58. The apparatus, as recited in claim 57, wherein the frame shear-ply is comprised of fibers orientated about 45°

relative to the length of the frame.

59. The apparatus, as recited in claim 49, wherein the stringer comprises a stringer shear-ply that extends partially around the core of the stringer.

60. The apparatus, as recited in claim 59, wherein the stringer shear-ply is comprised of fibers orientated about 45°

relative to the length of the stringer.

61. A single piece co-cured composite structure comprising:

a composite skin comprising an inner skin and an outer skin;

a composite frame having fibers, the frame extending inward from the outer skin; and

a composite stringer having fibers, the stringer extending inward from the outer skin, wherein the fibers of the stringer are interwoven with the fibers of the frame, wherein the skin, the frame, and the stringer form a single piece co-cured composite structure.

62. The apparatus, as recited in claim 61, wherein the fibers of the frame and the fibers of the stringer are interwoven with the skin.

63. The apparatus, as recited in claim 61, wherein the frame comprises a frame shear-ply, wherein the frame shear-ply is comprised of fibers orientated about 45°

relative to the length of the frame.

64. The apparatus, as recited in claim 61, wherein the stringer comprises a stringer shear-ply, wherein the stringer shear-ply is comprised of fibers orientated about 45°

relative to the length of the stringer.

65. The apparatus, as recited in claim 61, wherein the frame comprises fibers aligned along the length of the frame.

66. The apparatus, as recited in claim 61, wherein the stringer comprises fibers aligned along the length of the stringer.

67. A method for manufacturing a single piece co-cured structure comprising a skin, a frame, and a stringer, the skin comprising an inner skin and an outer skin, wherein the skin, frame, and stringer are interwoven together, the method comprising:

forming the inner skin of composite material on a mandrel comprising a frame provision and a stringer provision;

cutting the inner skin along the frame provision;

disposing a frame shear-ply of composite material within the frame provision to form the frame, the frame shear-ply covering a portion of the inner skin;

cutting the inner skin along the stringer provision;

disposing a stringer shear-ply of composite material within the stringer provision to form the stringer, the stringer shear-ply covering a portion of the inner skin;

forming the outer skin of composite material over the inner skin, frame shear-ply, and stringer shear-ply;

co-curing the skin, the frame, and the stringer as a single piece composite structure.

68. The method of claim 67, further comprising cutting the frame shear-ply along the stringer provision.

69. The method of claim 67, further comprising cutting the stringer shear-ply along the stringer provision.

70. The method of claim 67, further comprising removing the mandrel.

71. The method of claim 67, further comprising disposing frame core composite material within frame provision so that the frame shear-ply material partially surrounds the frame core composite material.

72. The method of claim 71, wherein the frame core composite material comprises unidirectional fibers aligned with the length of the frame provision.

73. The method of claim 67, further comprising disposing stringer core composite material within stringer provision so that the stringer shear-ply material partially surrounds the stringer core composite material.

74. The method of claim 73, wherein the stringer core composite material comprises unidirectional fibers aligned with the length of the stringer provision.

75. The method of claim 73, wherein frame comprises frame core composite material, the frame core composite material interwoven with the stringer core composite material.

76. The method of claim 67, further comprising disposing an insert tool within the frame provision of the mandrel.

77. The method of claim 76, wherein the insert tool comprises an insert stringer provision to facilitate interweaving the stringer with the frame.

78. The method of claim 76, further comprising disposing an inner support skin on the insert tool to help form the frame.

79. The method of claim 76, further comprising removing the insert tool from the frame provision of the mandrel, once the single piece composite structure has been cured.

80. The method of claim 67, further comprising disposing an insert tool within the stringer provision.

81. The method of claim 80, further comprising removing the insert tool from the stringer provision of the mandrel, once the single piece composite structure has been cured.

82. The method of claim 81, wherein an insert tool is disposed within the frame provision, wherein the insert tool disposed within the frame provision and the insert tool disposed within the stringer provision overlap.

83. The method of claim 67, further comprising disposing intersection pads at an intersection of the frame provision with the stringer provision on the mandrel.