Methods and apparatus for thermoplastic welding

Patent metadata

Field	Value
Publication number	US-10899081-B2
Application number	US-201816212598-A
Country	US
Kind code	B2
Filing date	Dec 6, 2018
Priority date	Dec 6, 2018
Publication date	Jan 26, 2021
Grant date	Jan 26, 2021

Abstract

An apparatus for thermoplastic welding includes at least one tool configured to support first and second thermoplastic composite parts in a first welding position having one or more joint lines between the first and second thermoplastic composite parts. The tool includes a plurality of induction coils. The apparatus further includes a susceptor removably positioned along the one or more joint lines. The susceptor is configured to heat the one or more joint lines when exposed to a magnetic flux generated by the plurality of induction coils to bond the first and second thermoplastic composite parts along the one or more joint lines. The apparatus also includes a susceptor removal device coupled to the susceptor and configured to remove the susceptor during bonding of the first and second thermoplastic composite parts.

First claim

What is claimed is:

1. An apparatus for thermoplastic welding, the apparatus comprising:
at least one tool configured to support first and second thermoplastic composite parts in a first welding position having one or more joint lines between the first and second thermoplastic composite parts, wherein the at least one tool comprises a plurality of induction coils;
a susceptor removably positioned along the one or more joint lines, the susceptor configured to heat the one or more joint lines when exposed to a magnetic flux generated by the plurality of induction coils to bond the first and second thermoplastic composite parts along the one or more joint lines; and
a susceptor removal device coupled to the susceptor and configured to direct a pulling force parallel to the one or more joint lines to remove the susceptor from the one or more joint lines during bonding of the first and second thermoplastic composite parts.

2. The apparatus of claim 1 , wherein the susceptor removal device comprises a rotating rod positioned adjacent to the first and second thermoplastic composite parts and rotatable to remove the susceptor from the one or more joint lines using the pulling force set at a level to overcome a resistance of melted material during bonding of the first and second thermoplastic parts.

3. The apparatus of claim 2 , wherein the at least one tool is configured to support a third thermoplastic composite part in a second welding position having one or more joint lines between the second and third thermoplastic composite parts, wherein the susceptor removal device is positioned between the first and second welding positions.

4. The apparatus of claim 3 , further comprising a guide rod aligned with each of (i) the first and second thermoplastic composite parts and (ii) the second and third thermoplastic composite parts, the guide rod configured to direct the pulling force in the direction parallel to the one or more joint lines.

5. The apparatus of claim 3 , further comprising a protective layer positioned along an exit direction of the susceptor from the (i) the first and second thermoplastic composite parts and (ii) the second and third thermoplastic composite parts, the protective layer positioned between the susceptor and the first thermoplastic composite part.

6. The apparatus of claim 2 , further comprising a third thermoplastic composite part in a second welding position having one or more joint lines between the second and third thermoplastic composite parts, wherein the susceptor removal device is positioned between the first and second welding positions and rotation of the rotating rod in a first direction removes the susceptor from the one or more joint lines at the first welding position and rotation of the rotating rod in a second direction opposite to the first direction removes the susceptor from the one or more joint lines at the second welding position.

7. The apparatus of claim 1 , further comprising a plurality of tools including a top tool and a bottom tool, the top tool configured to shield induced current within the first and second thermoplastic composite parts and the susceptor.

8. The apparatus of claim 1 , further comprising at least one temperature sensor positioned to measure a temperature of melted resin along the one or more joint lines, and wherein the susceptor removal device is configured to remove the susceptor under a tension loading when the melted resin reaches at least a predetermined temperature.

9. The apparatus of claim 1 , further comprising a plurality of additional welding positions and a plurality of susceptor removal devices between the plurality of additional welding positions, the plurality of susceptor removal devices communicatively coupled to a housing that is one of geared or belted to define a drive system that synchronizes movement of the plurality of susceptor removal devices to remove susceptors at the additional welding positions.

10. A method for thermoplastic welding, the method comprising:
positioning a first thermoplastic composite part at a welding position;
positioning a susceptor along a surface of the first thermoplastic composite part to define one or more joint lines;
positioning a second thermoplastic composite part on the first thermoplastic composite part with the susceptor between the first and second thermoplastic composite parts at the one or more joint lines;
generating a magnetic flux using a plurality of induction coils to cause the susceptor to heat the one or more joint lines between the first and second thermoplastic composite parts; and
removing the susceptor from the one or more joint lines after the heating of the one or more joint lines and prior to bonding of the first and second thermoplastic composite parts by directing a pulling force parallel to the one or more joint lines.

11. The method of claim 10 , wherein the heating by the susceptor causes localized thermoplastic welding along the one or more joint lines to form melted resin along the one or more joint lines with the susceptor removed from the melted resin.

12. The method of claim 10 , wherein the susceptor comprises a plurality of localized susceptor elements along the one or more joint lines, and the plurality of localized susceptor elements are at least one of a predetermined type or positioned at predetermined locations along the one or more joint lines.

13. The method of claim 10 , wherein the removing of the susceptor is performed concurrently with an application of a compactive load and further comprising cooling the one or more joint lines after removal of the susceptor.

14. The method of claim 10 , wherein the generated magnetic flux causes the susceptor to be heated to result in a resin melt bond line along the one or more joint lines, and removing the susceptor comprises drawing out the susceptor from the resin melt bond line under a tension loading when resin in the resin melt bond line reaches a predetermined temperature.

15. The method of claim 10 , further comprising positioning a protective layer between a removed susceptor portion and a portion of a thermoplastic sheet forming one of the first or second thermoplastic composite parts.

16. The method of claim 10 , further comprising removing the susceptor using a rotating rod, wherein the removed susceptor is guided to the rotating rod by one or more guide rods.

17. A system for thermoplastic welding, the system comprising:
a tool configured to support first and second thermoplastic composite parts in a first welding position having one or more joint lines between the first and second thermoplastic composite parts;
a magnetic field generator configured to generate magnetic flux;
a susceptor removably positioned along the one or more joint lines, the susceptor configured to heat the one or more joint lines when exposed to the magnetic flux to bond the first and second thermoplastic composite parts along the one or more joint lines; and
a susceptor removal device coupled to the susceptor and configured to direct a pulling force parallel to the one or more joint lines to remove the susceptor from the one or more joint lines during bonding of the first and second thermoplastic composite parts.

18. The system of claim 17 , wherein the magnetic field generator comprises a plurality of induction coils positioned within the tool.

19. The system of claim 17 , wherein the susceptor is configured to allow for removal by the pulling force in the direction parallel to the one or more joint lines, the pulling force set at a level to overcome a res

Assignees

• Boeing Co

Inventors

• Matsen Marc R
• Voss Bret Alan Mcginness
• Rubin Alexander M
• Prebil Charles R

Classifications

• B29C65/2038

  being a wire · CPC title

• B29C65/1432

  direct heating of the surfaces to be joined · CPC title

• B29C66/721

  Fibre-reinforced materials (B29C66/729 takes precedence) · CPC title

• B29C65/32 Primary

  Induction · CPC title

• B29C66/81455

  being a fluid inflatable bag or bladder, a diaphragm or a vacuum bag for applying isostatic pressure (inflatable element positioned between the joining tool and a backing-up part B29C66/82421) · CPC title