US4576776A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flow forming of composite material
Assignee: Boeing Commercial Airplane Co
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Filing: 1984-08-13
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Granted: 1986-03-18
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Expires: 2004-08-13
Abstract
Abstract This invention relates to methods and apparatus for forming composite material components that have relatively complex surfaces. Currently such components are very expensive to manufacture because forming them requires a good deal of time and hand working of the material. In the system of the invention, a flexible membrane (38) is heated to a forming temperature. Composite material (70) is laid on membrane (38) and heated evenly by contact with membrane (38). Fluid pressure is applied to membrane (38) to force membrane (38) and material (70) upwardly against a mold surface. While it is urged against the mold surface, material (70) flow forms to the shape of the mold surface. Preferably, the mold surface and membrane (38) are rotated about a horizontal axis approximately 180° to position the mold surface below membrane (38) before the fluid pressure is removed to allow membrane (38) to move out of contact with material (70).
Inventors
- 👤 Marlow C. Anderson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:12
CPC Classifications
B; B29; B29C; B29C70/00; B29C70/04; B29C70/28; B29C70/40; B29C70/42; B29C70/44; B29C35/00; B29C35/02; B29C35/0227; B29C35/0233; B29C43/00; B29C43/32; B29C43/52; B29C43/02; B29C43/10; B29C43/12
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
178 words
A method of forming into a desired shape composite material that includes a matrix material which is reinforced with a fibrous material and which has a critical cure temperature, comprising: positioning a mold surface generally above and spaced from and facing a flexible membrane; heating the membrane to a forming temperature at which the matrix material will flow into the desired shape and which is below the critical cure temperature of the matrix material; laying the composite material on the membrane, and allowing the matrix material to be heated evenly by contact with the membrane; when the matrix material has been heated to said forming temperature, applying fluid pressure to the heated membrane opposite the mold surface to force the membrane and the material thereon to move upwardly into contact with and against the mold surface; while maintaining the fluid pressure, allowing the matrix material to flow and the composite material to take the desired shape; and then removing the fluid pressure from the membrane to allow the membrane to move out of contact with the composite material.
Claim 2
Independent Claim
178 words
A method of forming into a desired shape composite material that includes a matrix material which is reinforced with a fibrous material and which has a critical cure temperature, comprising: positioning a mold surface generally above and spaced from and facing a flexible membrane; heating the membrane to a forming temperature at which the matrix material will flow into the desired shape and which is below the critical cure temperature of the matrix material; laying the composite material on the membrane, and allowing the matrix material to be heated evenly by contact with the membrane; when the matrix material has been heated to said forming temperature, applying fluid pressure to the heated membrane opposite the mold surface to force the membrane and the material thereon to move upwardly into contact with and against the mold surface; while maintaining the fluid pressure, allowing the matrix material to flow and the composite material to take the desired shape; and then removing the fluid pressure from the membrane to allow the membrane to move out of contact with the composite material.
Claim 3
Independent Claim
191 words
A method of forming into a desired shape composite material that includes a matrix material which is reinforced with a fibrous material and which has a critical cure temperature, comprising: positioning a mold surface generally above and spaced from and facing a flexible membrane; heating the membrane to a forming temperature at which the matrix material will flow into the desired shape and which is below the critical cure temperature of the matrix material; laying the composite material on the membrane, and allowing the matrix material to be heated evenly by contact with the membrane; when the matrix material has been heated to said forming temperature, applying fluid pressure to the heated membrane opposite the mold surface to force the membrane and the material thereon to move upwardly into contact with and against the mold surface; while maintaining the fluid pressure, allowing the matrix material to flow and the composite material to take the desired shape and rotating the mold surface and membrane about a horizontal axis about 180°; and then removing the fluid pressure from the membrane to allow the membrane to move out of contact with the composite material.
Claim 4
Independent Claim
191 words
A method of forming into a desired shape composite material that includes a matrix material which is reinforced with a fibrous material and which has a critical cure temperature, comprising: positioning a mold surface generally above and spaced from and facing a flexible membrane; heating the membrane to a forming temperature at which the matrix material will flow into the desired shape and which is below the critical cure temperature of the matrix material; laying the composite material on the membrane, and allowing the matrix material to be heated evenly by contact with the membrane; when the matrix material has been heated to said forming temperature, applying fluid pressure to the heated membrane opposite the mold surface to force the membrane and the material thereon to move upwardly into contact with and against the mold surface; while maintaining the fluid pressure, allowing the matrix material to flow and the composite material to take the desired shape and rotating the mold surface and membrane about a horizontal axis about 180°; and then removing the fluid pressure from the membrane to allow the membrane to move out of contact with the composite material.
Claim 5
Dependent Claim
42 words
A method as recited in claim 2, further comprising, after allowing the matrix material to flow and before removing the fluid pressure, applying a vacuum between the composite material and the mold surface to ensure that the composite material is completely formed.
Claim 6
Dependent Claim
44 words
A method as recited in claim 2, further comprising, after allowing the membrane to move out of contact, moving the mold surface and the composite material formed thereon away from the membrane and into an autoclave, and curing the composite material in said autoclave.
Claim 7
Independent Claim
269 words
A method of forming into a desired shape composite material that includes a matrix material which is reinforced with a fibrous material and which has a critical cure temperature, comprising: positioning a mold surface generally above and facing a flexible membrane; heating the membrane to a forming temperature at which the matrix material will flow into the desired shape and which is below the critical cure temperature of the matrix material; laying the composite material on the membrane, and allowing the matrix material to be heated evenly by contact with the membrane; applying fluid pressure to the heated membrane opposite the mold surface to force the membrane and the material thereon upwardly against the mold surface; while maintaining the fluid pressure, allowing the matrix material to flow and the composite material to take the desired shape and rotating the mold surface and membrane about a horizontal axis about 180°; then removing the fluid pressure from the membrane to allow the membrane to move out of contact with the composite material; and after allowing the membrane to move out of contact: moving the mold surface and the composite material formed thereon away from the membrane; positioning a second mold surface generally below and facing the membrane; rotating the second mold surface and the membrane about said axis about 180° to position the second mold surface generally above and facing the membrane; laying unformed composite material on the membrane, and allowing said unformed material to be heated evenly by contact with the membrane; and repeating the steps of applying, maintaining, and then removing fluid pressure to form said unformed composite material.
Claim 8
Independent Claim
269 words
A method of forming into a desired shape composite material that includes a matrix material which is reinforced with a fibrous material and which has a critical cure temperature, comprising: positioning a mold surface generally above and facing a flexible membrane; heating the membrane to a forming temperature at which the matrix material will flow into the desired shape and which is below the critical cure temperature of the matrix material; laying the composite material on the membrane, and allowing the matrix material to be heated evenly by contact with the membrane; applying fluid pressure to the heated membrane opposite the mold surface to force the membrane and the material thereon upwardly against the mold surface; while maintaining the fluid pressure, allowing the matrix material to flow and the composite material to take the desired shape and rotating the mold surface and membrane about a horizontal axis about 180°; then removing the fluid pressure from the membrane to allow the membrane to move out of contact with the composite material; and after allowing the membrane to move out of contact: moving the mold surface and the composite material formed thereon away from the membrane; positioning a second mold surface generally below and facing the membrane; rotating the second mold surface and the membrane about said axis about 180° to position the second mold surface generally above and facing the membrane; laying unformed composite material on the membrane, and allowing said unformed material to be heated evenly by contact with the membrane; and repeating the steps of applying, maintaining, and then removing fluid pressure to form said unformed composite material.
Claim 9
Dependent Claim
39 words
A method as recited in claim 5, comprising, following heating the membrane to said forming temperature, maintaining the membrane essentially at said forming temperature at least through the step of repeating the steps of applying and maintaining fluid pressure.
Claim 10
Dependent Claim
48 words
A method as recited in claim 5, further comprising, after moving the first mold surface and the composite material formed thereon away from the membrane, placing said first mold surface and composite material formed thereon inside an autoclave, and curing said composite material formed thereon in said autoclave.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-03-17 | 1989-09-16 | 1990-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-03-17 | 1993-09-16 | 1994-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-03-17 | 1997-09-16 | 1998-03-18 | $7700.00 | Window Closed / Lapsed |