COMPOSITE STRUCTURAL ELEMENT AND TORSION BOX

• US 20150239207A1
• Filed: 02/20/2015
• Published: 08/27/2015
• Est. Priority Date: 02/21/2014
• Status: Active Grant

• Current Assignee: Airbus Operations GmbH (Airbus SE)
• Original Assignee: Airbus Operations GmbH (Airbus SE)
• Inventors: SELYUGIN, Sergey, BALZER, Jan-Ronald
• Granted Patent: US 9,827,737 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B29C 70/202 arranged in parallel planes or structures of fibres crossing at substantial angles, e.g. cross-moulding compound [XMC] B29C70/207 takes precedence
• CPC Class Codes: B29C 70/30 Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core
• CPC Class Codes: B29C 70/543 Fixing the position or configuration of fibrous reinforcements before or during moulding for non-woven fabrics D04H3/08
• CPC Class Codes: B29K 2105/105 uni directionally
• CPC Class Codes: B29K 2105/108 arranged in parallel planes and crossing at substantial angles B29K2105/206 takes precedence
• CPC Class Codes: B29K 2307/04 Carbon
• CPC Class Codes: B29L 2031/3076 Aircrafts blades, propellers B29L2031/08
• CPC Class Codes: B32B 2260/021 Fibrous or filamentary layer layers of natural mineral fibres or particles being impregnated in a plastic substance B32B19/02
• CPC Class Codes: B32B 2260/046 Synthetic resin
• CPC Class Codes: B32B 2262/106 Carbon fibres, e.g. graphite fibres
• CPC Class Codes: B32B 2305/08 Reinforcements
• CPC Class Codes: B32B 2307/542 Shear strength
• CPC Class Codes: B32B 2307/544 Torsion strength; Torsion stiffness
• CPC Class Codes: B32B 2605/18 Aircraft blades, propellers B32B2603/00
• CPC Class Codes: B32B 5/12 characterised by the relative arrangement of fibres or filaments of different layers, e.g. the fibres or filaments being parallel or perpendicular to each other
• CPC Class Codes: B32B 5/26 another layer next to it also being fibrous or filamentary relative arrangement of fibres or filaments of different layers B32B5/12
• CPC Class Codes: B64C 3/185 Spars
• CPC Class Codes: B64C 3/187 Ribs
• CPC Class Codes: B64C 3/20 Integral or sandwich constructions
• CPC Class Codes: Y02T 50/40 Weight reduction
• CPC Class Codes: Y10T 428/24116 : Oblique to direction of web
• CPC Class Codes: Y10T 428/24124 : Fibers

Abstract

This relates to a composite structural element, in particular a rib or a spar, specifically for use in a torsion box of an aircraft structure such as a vertical tailplane, wherein the structural element defines a coordinate system with a first axis “a” wherein the structural element comprises a substantially planar main section defining a coordinate system with a first axis “a” extending along the longitudinal axis “L” of the structural element and a second axis “b” extending perpendicular to said longitudinal axis “L” within the planar main section and defining an angle of +90° with the first axis “a”, wherein the structural element contains a lay-up of single plies consisting of a fiber-reinforced composite material with a substantially unidirectional fiber orientation.

Claims

1. A composite structural element, for use in a torsion box of an aircraft structural component, comprising;

a substantially planar main section defining a coordinate system with a first axis extending along a longitudinal axis of the structural element and a second axis extending perpendicular to the longitudinal axis within a planar main section and defining an angle of +90°

with the first axis; and

a lay-up of single plies comprised of a fiber-reinforced composite material with a substantially unidirectional fiber orientation,

wherein the lay-up comprises at least one symmetrically arranged pair of a first and a second ply which are arranged in the lay-up such that the direction of fiber orientation extends in the coordinate system at an angle in the range of substantially −

17°

to −

23°

for the first ply and substantially +37°

to +43°

for the second ply.

2. The composite structural element of claim 1,

wherein the direction of fiber orientation of the first ply extends in the coordinate system at an angle of approximately −

20°

.

3. The composite structural element of claim 1,

wherein the direction of fiber orientation of the second ply extends in the coordinate system at an angle of approximately +40°

.

4. The composite structural element of claim 1,

wherein the first ply forms an outermost layer of the lay-up.

5. The composite structural element of claim 1,

wherein the lay-up comprises at least part of a web of the structural element.

6. The composite structural element of claim 1,

wherein the structural element is configured as a unitary member comprising the lay-up.

7. The composite structural element of claim 1,

wherein the lay-up comprises at least one symmetrically arranged pair of first and second plies.

8. The composite structural element of claim 1,

wherein the lay-up further comprises at least one ply with a direction of fiber orientation extending in the coordinate system at an angle in the range of substantially −

3°

to +3°

.

9. The composite structural element of claim 1,

wherein the lay-up further comprises at least one ply with a direction of fiber orientation extending in the coordinate system at an angle in the range of substantially +87°

to +93°

.

10. The composite structural element of claim 1,

further comprising at least two stiffeners extending substantially in a direction of +90°

in the coordinate system along the planar main section of the structural element.

11. The composite structural element of claim 10,

wherein the area between the two stiffeners has an aspect ratio as defined by the ratio of its longest and shortest extension of not less than 1.5.

12. The composite structural element of claim 10,

wherein area between the two stiffeners has an aspect ratio as defined by the ratio of its longest and shortest extension of not more than 4.0.

13. The composite structural element of claim 11,

wherein area between the two stiffeners has an aspect ratio as defined by the ratio of its longest and shortest extension of not more than 4.0.

14. The composite structural element of claim 1,

wherein the lay-up does not comprise more than 32 plies.

15. The composite structural element of claim 1,

wherein the lay-up does not exceed a thickness of 8 mm.

16. (canceled)