Method of manufacturing curved composite structural elements

Patent metadata

Field	Value
Publication number	US-9630390-B2
Application number	US-201314082839-A
Country	US
Kind code	B2
Filing date	Nov 18, 2013
Priority date	May 3, 2005
Publication date	Apr 25, 2017
Grant date	Apr 25, 2017

Abstract

A method of manufacturing curved composite structural elements can include fabricating a web ply in a flat curve over a removable substrate and laying up the ply on a curved web surface of a manufacturing tool. The method also can include laying up a diagonal ply with fibers oriented at +/−45° from the centerline of the web surface. The method further can include cutting a unidirectional composite tape into segments and laying up the tape segments to form a cross ply with a fiber orientation normal to the centerline of the web surface. One or both edges of the diagonal and cross plies may be folded over one or two sides of the manufacturing tool to form one or two flange surfaces. Additionally, a cap ply can be laid up on one or both flange surfaces using composite tape. The structural element layup can then be inspected and any excess composite material can be trimmed away.

First claim

What is claimed is:

1. A method of manufacturing a curved composite structural element, the method comprising the steps of:
laying up a 0-degree web ply formed of contiguously joined fiber composite strips onto a web surface of a manufacturing tool, the web surface having the shape of a planar arc as a flat curve, the manufacturing tool also having a first cap surface adjacent the web surface at one side thereof so as to form a first angle at a first corner with the web surface, and the first cap surface having a longitudinal centerline defining an inward or outward curve along which the first corner runs, whereby fibers of the laid up web ply are aligned in a 0-degree direction with a full length of a longitudinal centerline of the planar arc without substantial distortion;
laying up a 0-degree cap ply of fiber composite tape onto the first cap surface to form a splice with an edge of the laid up web ply along the first corner, the laid up cap ply comprising a plurality of tape fibers having 0-degree fiber orientation substantially aligned with the longitudinal centerline of the curved cap surface, and the splice resulting in a continuous, substantially 0-degree ply lying across the web and first cap surfaces;
laying up a diagonal ply comprising a composite material with a plurality of fibers over the continuous ply on the manufacturing tool by initially adhering an edge of the diagonal ply on the first cap surface of the manufacturing tool;
after said adhering, folding the diagonal ply over the first corner and onto the web surface of the manufacturing tool in order to form a first corner in the diagonal ply between the first cap surface and the web surface;
uniformly spreading the folded diagonal ply over the web surface so as to avoid wrinkles in the diagonal ply on the web surface; and
curing the resulting layup of the diagonal and continuous plies after said spreading.

2. The method of claim 1 , wherein the plurality of fibers of the diagonal ply form approximate 45-degree angles with a tangent of the longitudinal centerline of the web surface at all points thereof.

3. The method of claim 1 , further comprising:
after said uniformly spreading but prior to said curing, additionally folding the diagonal ply over a second cap surface of the manufacturing tool in order to form a second corner in the diagonal ply between the web surface and the second cap surface, the second cap surface arranged at an opposite side of the web surface with respect to the first cap surface so as to form a second angle at a second corner with the web surface, and the second cap surface having the opposite of an inward or outward curve with respect to the first cap surface.

4. The method of claim 3 , wherein said additional folding results in the diagonal ply having a “C” shape.

5. The method of claim 1 , further comprising the step of laying up a cross ply over the web surface.

6. The method of claim 1 , wherein the composite material of one or more of the web, cap, and diagonal plies is selected from the group consisting of: a polymer matrix, epoxy, polyether ether ketone, polyether ketone ketone, and polyphenylene sulfide.

7. The method of claim 6 , wherein the fibers of one or more of the web, cap, and diagonal plies are selected from the group consisting of: carbon, aramid, glass, poly paraphenylene terephthalamide, boron, and quartz, and wherein the fibers of one or more of the web, cap, and diagonal plies are intermixed with a substance selected from the group consisting of: a metal, a TiGr metal foil, and a fiber metal laminate.

8. The method of claim 1 , wherein said folding results in the diagonal ply having an “L” shape.

9. A method of manufacturing a curved composite structural element, the method comprising the steps of:
laying up a 0-degree web ply formed of contiguously joined fiber composite strips onto a web surface of a manufacturing tool, the web surface having the shape of a planar arc as a flat curve, the manufacturing tool also having first and second cap surfaces each adjacent the web surface at opposed sides thereof so as to form first and second angles with the web surface at first and second corners respectively, and the first and second cap surfaces having an inward and outward curve respectively, whereby fibers of the laid up 0-degree web ply are aligned in a 0-degree direction with a full length of a longitudinal centerline of the planar arc without substantial distortion;
laying up a 0-degree cap ply of fiber composite tape onto the first or second cap surface to form a splice with an edge of the laid up web ply along the first or second corner respectively, the laid up cap ply comprising a plurality of tape fibers having 0-degree fiber orientation substantially aligned with a longitudinal centerline of the respective cap surface onto which the cap ply is laid UP, and the splice resulting in a continuous, substantially 0-degree ply lying across the web surface and respective cap surface;
cutting a composite tape into a plurality of segments, wherein the composite tape includes a plurality of tape fibers having a general tape fiber orientation;
laying up a cross ply over the continuous ply by first laying up the plurality of segments on the first cap surface of the manufacturing tool;
after said laying up of the cross ply, folding the cross ply over the first corner onto the web surface and then over the second corner onto the second cap surface of the manufacturing tool in order to form a first corner in the cross ply between the web surface and the first cap surface and a second corner in the cross ply between the web surface and the second cap surface wherein the tape fiber orientation of the cross ply substantially forms a right angle with a tangent of the longitudinal centerline of the web surface at all points thereof; and
curing the resulting layup of the cross and continuous plies after said folding.

10. The method of claim 9 , wherein said cutting of the plurality of segments comprises cutting the plurality of segments into trapezoidal shapes such that as a result of said laying up of the cross ply on the web surface of the manufacturing tool, a pair of nonparallel sides of ones of the plurality of segments substantially form right angles with the longitudinal centerline of the web surface.

11. The method of claim 9 , wherein the folding of the cross ply comprises uniformly spreading the cross ply over the web surface so as to avoid wrinkles in the composite material of the cross ply on the web surface, and wherein the method further comprises curing the resulting layup of cross and continuous plies.

12. The method of claim 9 , wherein the composite material of one or more of the web, cap, and cross plies is selected from the group consisting of: a polymer matrix, epoxy, polyether ether ketone, polyether ketone ketone, and polyphenylene sulfide.

13. The method of claim 12 , wherein the fibers of one or more of the web, cap, and cross plies are selected from the group consisting of: carbon, aramid, glass, poly paraphenylene terephthalamide, boron, and quartz, and wherein the fibers of one or more of the web, cap, and cross plies are intermixed with a substance selected from the group consisting of: a metal, a TiGr metal foil, and a fiber metal laminate.

14. The method of claim 9 , wherein the composite tape forming the segments comprises a pre-preg tape.

15. The method of claim 9 , wherein said folding results in the cross ply having a “C” shape.

16. A method comprising:
forming a 0-degree web ply of fiber composite strips by placing the strips to lay contiguously adjoined on a fla

Assignees

• Boeing Co

Inventors

• Brown Todd A
• Friddell Stephen Douglas
• Harris Christopher G
• Modin Andrew E

Classifications

• Y10T156/1051

  by folding · CPC title

• Y10T156/108

  Flash, trim or excess removal · CPC title

• B29L2031/3082

  Fuselages · CPC title

• Y10T156/1075

  of plural laminae from single stock and assembling to each other or to additional lamina · CPC title

• B29K2067/00

  Use of polyesters {or derivatives thereof}, as moulding material · CPC title