Thermoplastic welding apparatus and related methods

Patent metadata

Field	Value
Publication number	US-2017165902-A1
Application number	US-201715411589-A
Country	US
Kind code	A1
Filing date	Jan 20, 2017
Priority date	May 17, 2011
Publication date	Jun 15, 2017
Grant date	—

Abstract

Thermoplastic welding apparatus and related methods are disclosed. An example method includes providing a smart susceptor between composite parts that are to be joined via thermoplastic welding. The example method includes positioning the composite parts and the smart susceptor on a tooling surface within a cavity of a tooling apparatus and applying a seal to the composite parts and the tooling surface to form a vacuum chamber between the composite parts and the tooling surface at a welding joint of the composite parts; producing a magnetic field at the welding joint. The example method includes providing a vacuum in the vacuum chamber during a welding operation.

First claim

1 . A method comprising:
providing a smart susceptor between composite parts that are to be joined via thermoplastic welding; positioning the composite parts and the smart susceptor on a tooling surface within a cavity of a tooling apparatus; applying a seal to the composite parts and the tooling surface to form a vacuum chamber between the composite parts and the tooling surface at a welding joint of the composite parts; producing a magnetic field at the welding joint; and providing a vacuum in the vacuum chamber during a welding operation.

2 . The method of claim 1 , further including applying the seal to perimeter edges of the composite parts when the composite parts are positioned on the tooling surface of the tooling apparatus, and applying the seal to the tooling surface adjacent the perimeter edges of the composite parts.

3 . The method of claim 1 , further comprising applying a pressure to the composite parts positioned outside of the vacuum chamber that is greater than the vacuum applied to the composite parts positioned inside of the vacuum chamber to provide a welding pressure to compress the smart susceptor between the composite parts during welding.

4 . The method of claim 1 , wherein producing the magnetic field includes generating a magnetic field that is oriented substantially parallel to a plane of the smart susceptor and planes of the composite parts to be joined via thermoplastic welding.

5 . The method of claim 4 , further comprising positioning a ferromagnetic material adjacent the cavity to direct the magnetic field flux to the smart susceptor and reduce leakage of the magnetic field flux to the composite parts.

6 . The method of claim 5 , further comprising positioning a non-electrically conductive material in the cavity of the tooling surface adjacent at least one of the composite parts.

7 . The method of claim 6 , further including positioning a ferromagnetic material in the tooling surface adjacent the non-electrically conductive material.

8 . The method of claim 6 , wherein generating a magnetic field in parallel relationship to the plane of the smart susceptor includes placing a non-electrically conductive material in contact with the at least one of the composite parts and providing at least one ferrite material adjacent the non-electrically conductive material.

9 . The method of claim 1 , further comprising applying a tooling force to compress the smart susceptor between the composite parts during welding.

10 . A method comprising:
positioning a smart susceptor between a first composite part and second composite part; positioning the first composite part, the second composite part and the smart susceptor in a cavity formed between opposing first and second tools of a thermoplastic welding apparatus such that the first composite part engages a first tooling surface of the first tool; applying a tape to a perimeter of the first composite part and the second composite part and only to a portion of the first tooling surface about perimeter edges of the first composite part and the second composite part to form a gas seal over a welding joint defined by the smart susceptor and the first and second composite parts; applying a pressure to cause the smart susceptor to compress between the first composite part and the second composite part; and generating a first magnetic field adjacent the smart susceptor via a first inductor provided in the first tool adjacent the tooling surface.

11 . The method of claim 10 , wherein applying the welding pressure includes providing a pressure differential between the cavity and the gas seal.

12 . The method of claim 11 , wherein providing the pressure differential includes providing a vacuum to the gas seal inside the perimeter defined by the tape and applying a pressure in the cavity and outside of the perimeter defined by the tape that is greater than the vacuum.

13 . The method of claim 12 , wherein the vacuum enables the parts and the smart susceptor to be held in contact at the welding joint when the parts are being welded together.

14 . The method of claim 10 , further including generating a second magnetic field adjacent the smart susceptor via a second magnetic inductor provided in the second tool.

15 . The method of claim 10 , further including applying the tape to the first and second composite parts and the first tooling surface such that the tape forms an L-shape.

16 . The method of claim 15 , further including attaching a first leg of the tape to a first side surface of the first composite part and a first side surface of the second composite part, and attaching a second leg of the tape to the portion of the first tooling surface adjacent the first and second composite parts.

17 . A method comprising:
positioning a smart susceptor between opposing surfaces of at least two component parts; positioning the component parts and the smart susceptor on a tooling surface defining a cavity of the welding tool; sealing a perimeter of the component parts and a portion of the tooling surface adjacent the perimeter of the component parts to provide a sealed portion in communication with the tooling surface and a non-sealed portion in communication with the cavity; applying a pressure differential to a weld joint of the component parts between the sealed portion and the non-sealed portion to compress the smart susceptor between the component parts during a welding operation; and generating a magnetic flux field oriented generally parallel to a plane of the smart susceptor during the welding operation.

18 . The method of claim 17 , wherein applying the pressure differential includes applying a vacuum in the sealed portion and applying a pressure in the non-sealed portion that is greater than the vacuum.

19 . The method of claim 17 , wherein sealing the perimeter includes applying a tape to the perimeter of the component parts and the portion of the tooling surface adjacent the perimeter of the component parts, the tape forming the sealed portion about the perimeter of the component parts and the portion of the tooling surface on which the component parts are positioned.

20 . The method of claim 17 , wherein positioning the smart susceptor between the component parts includes placing a molypermalloy between the opposing surfaces of the component parts.

Assignees

• Boeing Co

Inventors

• Matsen Marc R
• Negley Mark A
• Geren William Preston
• Miller Robert

Classifications

• B29C66/7394

  characterised by the material of at least one of the parts being a thermoset · CPC title

• B29C66/7212

  characterised by the composition of the fibres · CPC title

• B29C66/1122

  Single lap to lap joints, i.e. overlap joints (B29C66/45, B29C66/472, B29C66/52272 take precedence) · CPC title

• B29C66/7392

  characterised by the material of at least one of the parts being a thermoplastic · CPC title

• H05B2206/023

  using the curie point of the material in which heating current is being generated to control the heating temperature · CPC title