Automated fiber-placement systems and methods

Patent metadata

Field	Value
Publication number	US-10828848-B2
Application number	US-201916363772-A
Country	US
Kind code	B2
Filing date	Mar 25, 2019
Priority date	Mar 25, 2019
Publication date	Nov 10, 2020
Grant date	Nov 10, 2020

Abstract

An automated fiber-placement method comprises delivering a first quantity of pulsed energy to first portions of at least one fiber-reinforced tape strip, and delivering a second quantity of pulsed energy to second portions of at least the one fiber-reinforced tape strip, alternating with the first portions. Each one of the second portions at least partially overlaps two adjacent ones of the first portions such that overlapping regions of the first portions and the second portions have a higher temperature than non-overlapping regions of the first portions and the second portions. The automated fiber-placement method further comprises laying down at least the one fiber-reinforced tape strip against a substrate along a virtual curvilinear path, such that (i) at least the one fiber-reinforced tape strip is centered on the virtual curvilinear path, and (ii) the overlapping regions are transformed into discrete tape-regions, geometrically different from the overlapping regions.

First claim

The invention claimed is:

1. An automated fiber-placement method, comprising steps of:
delivering a first quantity of pulsed energy to first portions of at least one fiber-reinforced tape strip;
delivering a second quantity of pulsed energy to second portions of at least the one fiber-reinforced tape strip, alternating with the first portions, and wherein:
each one of the second portions of at least the one fiber-reinforced tape strip at least partially overlaps two adjacent ones of the first portions of at least the one fiber-reinforced tape strip such that overlapping regions of the first portions and the second portions have a higher temperature than non-overlapping regions of the first portions and the second portions;
at least the one fiber-reinforced tape comprises a first longitudinal tape-edge and a second longitudinal tape-edge, parallel to the first longitudinal tape-edge and spaced from the first longitudinal tape-edge by a tape-strip width; and
at least the one fiber-reinforced tape strip comprises a resin tape-matrix and unidirectional reinforcement fibers, imbedded in the resin tape-matrix; and

laying down at least the one fiber-reinforced tape strip against a substrate along a virtual curvilinear path, such that:
at least the one fiber-reinforced tape strip is centered on the virtual curvilinear path; and
the overlapping regions of at least the one fiber-reinforced tape strip are transformed into discrete tape-regions, geometrically different from the overlapping regions.

2. The automated fiber-placement method according to claim 1 , wherein the overlapping regions are smaller than the non-overlapping regions.

3. The automated fiber-placement method according to claim 1 , wherein:
the virtual curvilinear path comprises an arc, having a radius that is measured from a virtual point on a virtual line that is perpendicular to the virtual curvilinear path and intersects the first longitudinal tape-edge and the second longitudinal tape-edge;
a ratio of the tape-strip width to the radius is equal to or greater than 0.003;
within each of the discrete tape-regions, one of the unidirectional reinforcement fibers that is closest to the first longitudinal tape-edge is more buckled than another one of the unidirectional reinforcement fibers that is closest to the second longitudinal tape-edge; and
ones of the unidirectional reinforcement fibers that are buckled are parallel to the substrate.

4. The automated fiber-placement method according to claim 3 , wherein the arc has an arc length that is equal to or greater than a product of the radius and π/64.

5. The automated fiber-placement method according to claim 3 , wherein:
the steps of delivering the first quantity of pulsed energy to the first portions of at least the one fiber-reinforced tape strip and delivering the second quantity of pulsed energy to the second portions of at least the one fiber-reinforced tape strip comprise heating a first array of locations within the overlapping regions of the first portions and the second portions of at least the one fiber-reinforced tape strip to a higher temperature than a second array of locations within the overlapping regions of the first portions and the second portions of at least the one fiber-reinforced tape strip; and
locations in the first array of locations are closer to the virtual point than locations in the second array of locations.

6. The automated fiber-placement method according to claim 3 , wherein:
at least the one fiber-reinforced tape strip is a plurality of fiber-reinforced tape strips;
the step of laying down at least the one fiber-reinforced tape strip against the substrate along the virtual curvilinear path comprises laying down the plurality of fiber-reinforced tape strips in a parallel array of continuous strips;
the steps of delivering the first quantity of pulsed energy to the first portions of at least the one fiber-reinforced tape strip and delivering the second quantity of pulsed energy to the second portions of at least the one fiber-reinforced tape strip comprise heating the overlapping regions of a first subset of the plurality of fiber-reinforced tape strips to a higher temperature than the overlapping regions of a second subset of the plurality of fiber-reinforced tape strips; and
strips of the second subset of the plurality of fiber-reinforced tape strips are farther away from the virtual point than strips of the first subset of the plurality of fiber-reinforced tape strips.

7. The automated fiber-placement method according to claim 6 , further comprising steps of:
detecting a property of the plurality of fiber-reinforced tape strips after delivery of the first quantity of pulsed energy and delivery of the second quantity of pulsed energy; and
controlling at least one of the first quantity of pulsed energy, the second quantity of pulsed energy, or a rate of laying down at least the one fiber-reinforced tape strip against the substrate along the virtual curvilinear path responsive to the property of the plurality of fiber-reinforced tape strips.

8. The automated fiber-placement method according to claim 1 , wherein the tape-strip width is between 5 millimeters (0.2 inches) and 15 millimeters (0.6 inches).

9. The automated fiber-placement method according to claim 1 , wherein, within each of the discrete tape-regions, at least one of the unidirectional reinforcement fibers that are buckled comprises a plurality of folds.

10. The automated fiber-placement method according to claim 1 , wherein the discrete tape-regions are trapezoidal.

11. The automated fiber-placement method according to claim 1 , wherein the step of laying down at least the one fiber-reinforced tape strip against the substrate along the virtual curvilinear path results in the non-overlapping regions becoming intermediate tape-regions, separated from each other by the discrete tape-regions.

12. The automated fiber-placement method according to claim 11 , wherein within each of the intermediate tape-regions, all of the unidirectional reinforcement fibers are only straight.

13. The automated fiber-placement method according to claim 1 , wherein each of the unidirectional reinforcement fibers that are buckled within the discrete tape-regions are less buckled within the intermediate tape-regions than within the discrete tape-regions.

14. The automated fiber-placement method according to claim 11 , wherein the intermediate tape-regions are rectangular.

15. The automated fiber-placement method according to claim 1 , further comprising steps of:
detecting a property of at least the one fiber-reinforced tape strip after delivery of the first quantity of pulsed energy and delivery of the second quantity of pulsed energy; and
controlling at least one of the first quantity of pulsed energy, the second quantity of pulsed energy, or a rate of laying down at least the one fiber-reinforced tape strip against the substrate along the virtual curvilinear path responsive to the property of at least the one fiber-reinforced tape strip.

16. The automated fiber-placement method according to claim 15 , wherein the property is temperature.

17. The automated fiber-placement method according to claim 1 , wherein the virtual curvilinear path is nonplanar.

18. The automated fiber-placement method according to claim 1 , wherein the overlapping regions and the non-overlapping regions are identical in size.

19. The automated fiber-placement method according to claim 1 , wherein the discrete tape-regions are structurally different from the overlap

Assignees

• Boeing Co

Inventors

• Johnson Brice A
• Ghose Sayata
• Malik Kevin F

Classifications

• B29C35/0288

  Controlling heating or curing of polymers during moulding, e.g. by measuring temperatures or properties of the polymer and regulating the process (controlling or regulating chemical, physical or physico- chemical processes in general B01J19/0006) · CPC title

• B29L2031/3082

  Fuselages · CPC title

• B29C66/944

  by controlling or regulating the time · CPC title

• B29C66/939

  characterised by specific speed values or ranges · CPC title

• B29C66/934

  by controlling or regulating the speed · CPC title