Methods And Systems For Forming Reinforced Composite Articles Having Variable Thickness Corners

• US 20130189482A1
• Filed: 07/25/2012
• Published: 07/25/2013
• Est. Priority Date: 07/27/2011
• Status: Active Grant

• Current Assignee: DIEFFENBACHER GmbH Maschinen- und Anlagenbau
• Original Assignee: Fiberforge Corporation
• Inventors: Dequine, Dustin Louis
• Granted Patent: US 8,771,575 B2
• Time in Patent Office: Days
• US Class Current: 428/130
• CPC Class Codes: B29C 43/003 characterised by the choice of material
• CPC Class Codes: B29C 43/52 Heating or cooling
• CPC Class Codes: B29C 70/207 arranged in parallel planes of fibres crossing at substantial angles
• CPC Class Codes: B29C 70/46 using matched moulds, e.g. for deforming sheet moulding compounds [SMC] or prepregs
• CPC Class Codes: B29D 99/0003 Producing profiled members, e.g. beams
• CPC Class Codes: Y10T 428/2419 Fold at edge
• CPC Class Codes: Y10T 428/24264 Particular fold structure [e.g., beveled, etc.]

Abstract

A method for making parts with variable thickness corners and parts with variable thickness corners are disclosed. The method includes laying up multiple plies to form a tailored blank, associating the blank with a convex and concave die, and applying pressure and heat so that material from at least one of the plies migrates towards a voided corner area formed between the dies.

Claims

1. A method for manufacturing a composite part from a blank having a first ply oriented in a first direction and a second ply oriented in a second direction transverse to the first direction, the method comprising:

positioning the blank between a convex die and a concave die, with the first ply oriented generally parallel to a longitudinal direction in which a corner of the concave die extends, and with the second ply oriented generally transverse to the longitudinal direction in which the corner of the concave die extends; and

pressing the blank between the convex die and concave die such that a portion of the first ply migrates into the corner.

2. The method of claim 1, wherein the blank comprises resin, and wherein the method comprises pressing the blank between the convex die and concave die such that the resin migrates toward the corner in between plies.

3. The method of claim 1, wherein the blank has a first outer ply facing the concave die and a second outer ply facing the convex die, and wherein the first and second outer plies are positioned at approximately 90 degrees with respect to the first ply.

4. The method of claim 3, wherein the blank has a plurality of plies that are oriented in the first direction and are positioned near the first outer ply.

5. The method of claim 4, wherein a portion of each of the plurality of plies migrates into the corner.

6. The method of claim 1, wherein a radius of the concave die that generates the corner of the composite part is less than a radius of the convex die that generates the corner plus the thickness of a section adjacent to the corner.

7. The method of claim 1, wherein the composite part comprises an elongated member, and wherein the first ply is oriented generally parallel to a longitudinal axis of the elongated member and the second ply is oriented generally transverse to the longitudinal axis of the elongated member.

8. The method of claim 1, wherein the blank further comprises a third ply between the first ply and the second ply, and wherein the third ply is oriented at an angle to the first ply and the second ply.

9. The method of claim 8, wherein the first ply is oriented at approximately 0 degrees, the second ply is oriented at approximately 90 degrees, and the third ply is oriented at approximately 45 degrees.

10. The method of claim 1, further comprising heating the blank.

11. The method of claim 10, further comprising heating one or both dies.

12. A method for manufacturing a composite part from a blank, having a first ply oriented in a first direction and a second ply oriented in a second direction, wherein the second direction is different from the first direction, the method comprising:

positioning the blank between a convex die and a concave die, with the second ply oriented generally parallel to a longitudinal direction in which a corner of the concave die extends; and

pressing the blank between the convex die and concave die such that the thickness of a portion of the second ply in the corner increases and the thickness of a portion of the first ply in the corner does not substantially change.

13. The method according to claim 12, wherein the blank further comprises a third ply oriented in a third direction and wherein the third direction is different from the second direction and wherein the second ply is disposed between the first ply and the third ply.

14. The method according to claim 12, wherein pressing the blank between the convex die and the concave die comprises using hydrostatic pressure.

15. The method according to claim 12, wherein pressing generates a structural member that is thicker at the corners than in the adjacent non-corner regions.

16. The method according to claim 12, wherein the first direction is angled with respect to the second direction by an angle in the range between 10 degrees and 80 degrees.

17. The method according to claim 12, wherein the blank further includes a third ply and wherein the first ply interfaces with the convex die and the third ply interfaces with the concave die, and wherein the first ply and the third ply are oriented at any angle between 45 degrees and 90 degrees or between negative 45 degrees and negative 90 degrees with respect to the longitudinal direction.

18. The method according to claim 17, wherein the second ply is disposed between the first ply and the third ply and wherein the second ply is generally oriented at an angle between negative five degrees and five degrees with respect to the longitudinal direction of the dies.

19. The method according to claim 12, wherein the first ply comprises a composite material including resin and reinforcing fibers, and wherein the relative locations of the reinforcing fibers disposed in the corner changes as the blank is pressed.

20. The method according to claim 12, wherein the first ply is pulled in from outside the part and conformed to the concave die.

21. The method according to claim 12, wherein the die material is comprised of one of metal and metal alloy.

22. The method according to claim 12, wherein the concave die is one of coated and plated with a non-stick material.

23. The method according to claim 12, wherein the convex die and concave die provide a hard-tooled gap on one side of a variable-thickness corner that is less than a hard-tooled gap on the other side of the variable-thickness corner.

24. A composite part, comprising:

a corner associated with the interface of a first adjacent section of the part and a second adjacent section of the part;

the corner having a first thickness, wherein the first thickness is measured between an interior surface of the corner and an exterior surface of the corner;

the first adjacent part and the second adjacent part having thicknesses greater than or equal to a second thickness; and

wherein the first thickness is substantially greater than the second thickness.

25. The composite part according to claim 24, wherein the interior surface of the corner is associated with an interior radius of curvature and the external surface is associated with an external radius of curvature and wherein the external radius of curvature is less than the internal radius of curvature plus the second thickness.

26. The composite part according to claim 24, wherein the first adjacent section is a substantially flat section with approximately constant thickness.

27. The composite part according to claim 24, wherein the part is a stringer-type part.

28. The composite part according to claim 27, wherein the first adjacent section is a flange section and wherein the second adjacent section is a web section