Method of forming a reinforced foam-filled composite stringer

• US 9,694,895 B2
• Filed: 06/18/2013
• Issued: 07/04/2017
• Est. Priority Date: 11/25/2008
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Rotter, Daniel M., Senibi, Simon D., Van West, Barry P., Guzman, Juan Carlos, McCarville, Douglas A.
• Primary Examiner(s): Golden, Chinessa
• Application Number:
  US13/920,085
• Publication Number:
  US 20130280491A1
• Time in Patent Office: 1,477 Days
• Field of Search: None
• CPC Class Codes: B32B 1/08 Tubular products
• CPC Class Codes: B32B 15/046 of foam
• CPC Class Codes: B32B 15/18 comprising iron or steel B32B15/011, B32B15/012 and B32B15/013 take precedence
• CPC Class Codes: B32B 15/20 comprising aluminium or copper B32B15/016 and B32B15/017 take precedence
• CPC Class Codes: B32B 2266/08 Closed cell foam
• CPC Class Codes: B32B 2307/558 Impact strength, toughness
• CPC Class Codes: B32B 2605/18 Aircraft
• CPC Class Codes: B32B 27/00 Layered products comprising a layer of synthetic resin fibrous or filamentary layer made of a synthetic resin B32B5/02; particulate layer made of a synthetic resin B32B5/16; foamed layer made of a synthetic resin B32B5/18
• CPC Class Codes: B32B 3/26 characterised by a particular shape of the outline of the cross-section of a continuous layer; characterised by a layer with cavities or internal voids foam layer B32B5/18; layer of synthetic resin characterised by fillers that create voids or cavities B32B27/205; characterised by an apertured layer
• CPC Class Codes: B32B 3/28 characterised by a layer comprising a deformed thin sheet , i.e. the layer having its entire thickness deformed out of the plane, e.g. corrugated, crumpled B32B29/08 takes precedence
• CPC Class Codes: B32B 5/18 characterised by features of a layer of foamed material
• CPC Class Codes: B32B 9/005 comprising one layer of ceramic material, e.g. porcelain, ceramic tile layered products with at least two ceramic layers composed mainly of ceramic B32B18/00
• CPC Class Codes: B32B 9/007 comprising carbon, e.g. graphite, composite carbon
• CPC Class Codes: B64C 1/064 Stringers; Longerons
• CPC Class Codes: Y10T 428/233 Foamed or expanded material encased
• CPC Class Codes: Y10T 428/24504 Component comprises a polymer [e.g., rubber, etc.]

Abstract

A method and apparatus for manufacturing a composite stringer. A composite material and foam are laid up onto a tool in the form of a stringer. The foam has a plurality of structural members within the foam. The plurality of structural members has a number of orientations to resist a number of loads. The composite material, the foam in the form of the stringer, and the plurality of structural members are cured to form the composite stringer.

Claims

1. An apparatus comprising:

a composite material defining a channel;

a structure that comprises a skin ply connected to the composite material such that the skin ply retains a foam disposed in the channel; and

a plurality of pins in the foam and the composite material, such that the plurality of pins remain located completely between interior surfaces of the structure and arranged in a three dimensional grid that comprises;

a resistance to loads on the composite material;

a first set of pins, in the plurality of pins, that comprises a first orientation approximately 45 degrees offset relative to an orientation of the skin ply; and

a second set of pins in the plurality of pins, that comprises a second orientation approximately 135 degrees offset relative to the orientation of the skin ply.

2. The apparatus of claim 1, wherein the plurality of pins contact the composite material, and the loads on the composite material are compression loads.

3. The apparatus of claim 1, wherein the composite material is cured.

4. The apparatus of claim 1, wherein the plurality of pins extend from the skin ply to a first wall and a second wall of the channel.

5. The apparatus of claim 1, wherein the composite material comprises a hollow stringer of an aircraft.

6. The apparatus of claim 1, wherein the plurality of pins comprise a material selected from the group consisting of aluminum, steel, carbon, titanium, metal alloy, and ceramic material.

7. The apparatus of claim 1, wherein the foam comprises a material selected from the group consisting of polyisocyanurate, aromatic polyester, polyimide, styrene acrylo-nitrile, polymethacrylimide, polyetherimide, polyphenylene, polyetherether-ketone, polyvinylidene fluoride, and poly vinyl chloride.

8. The apparatus of claim 1, wherein the foam comprises a cellular polymer foam.

9. The apparatus of claim 1, wherein a pin in the plurality of pins is one of hollow or solid.

10. The apparatus of claim 1, wherein a pin in the plurality of pins comprises a shape selected from the group consisting of circular, square, rectangular, and triangular.

11. The apparatus of claim 1, further comprising a plurality of structural members, wherein the plurality of structural members comprise a third orientation, relative to the orientation of the skin ply, configured to resist a number of compression loads.

12. A noise attenuator that comprises:

a composite material formed into a hat shape, the composite material defining a channel;

a structure that comprises a skin ply connected to the composite material such that the skin ply retains a foam disposed in the channel; and

a plurality of pins in the foam, such that the plurality of pins remain located completely between interior surfaces of the structure and arranged in a three dimensional grid that comprises a first set of pins, in the plurality of pins, that comprises a first orientation, and a second set of pins in the plurality of pins, that comprises a second orientation, each orientation offset respectively relative to the orientation of the skin ply, such that the plurality of pins comprise a resistance to a load on the composite material.

13. The noise attenuator of claim 12, wherein the plurality of pins have a first density in a first area of the noise attenuator and a second density in a second area of the noise attenuator, the first density different from the second density.

14. The noise attenuator of claim 13, wherein the first area of the noise attenuator is subject to higher compression loads than the second area, and the first density is greater than the second density.

15. The noise attenuator of claim 12, wherein the plurality of pins extend from the skin ply to a first wall and a second wall of the channel.

16. A structure-that comprises:

a composite material that comprises a shape that comprises a channel;

a skin ply connected to the composite material and configured to retain a foam disposed in the channel; and

a plurality of tubes in the foam such that the plurality of tubes remain located completely between inside surfaces of the channel and arranged in a three dimensional grid that comprises a first set of tubes in the plurality of tubes, that comprises a first orientation and a second set of tubes in the plurality of tubes, that comprises a second orientation approximately normal to the first orientation, and each orientation offset respectively relative to the orientation of the skin ply, such that the plurality of tubes comprise a resistance to a load on the composite material.

17. The structure of claim 16, wherein the composite material, the foam, and the plurality of tubes comprise a first stringer and further comprising a second stringer connected to the skin ply.

18. The structure of claim 17, wherein the first stringer, the second stringer, and the skin ply comprise an aircraft panel.

19. The structure of claim 17, wherein the structure comprises a structural vibration dampener.

20. The structure of claim 17, wherein the structure comprises a noise attenuator.