US4591400A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming a fiber reinforced composite article of a complex configuration
Assignee: RTX Corp
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Filing: 1984-05-15
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Granted: 1986-05-27
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Expires: 2004-05-15
Abstract
Abstract The present invention is a method of making fiber reinforced composite articles using match molds to compact a partially hollow fiber/matrix lay-up. The method comprises wrapping the matrix and fiber reinforcement about a mandrel, removing the mandrel from the lay-up or chilling the wrapped mandrel allowing for easy removal of the mandrel resulting in a relatively stiff hollow lay-up. The lay-up is then placed in a mold and compacted and cured to form the desired composite article. Such a method provides an easy method to form such complex composite article shapes as I-beam, C-beam, etc.
Inventors
- 👤 Evan A. Fradenburgh
- 👤 Edmond F. Kiely
- 👤 Gordon G. Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 16:16
CPC Classifications
B; B29; B29D; B29D99/00; B29D99/0003; B29D99/0007; B29C; B29C33/00; B29C33/44; B29C33/48; B29C70/00; B29C70/04; B29C70/28; B29C70/30; B29C70/34; B29C70/347; B29C70/68; B29C70/86
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
128 words
A method of making a composite flexbeam of complex configuration having an inboard end and an outboard end comprising: (a) forming a lay-up of fiber reinforcing material and matrix material about a rectangular mandrel, (b) chilling the lay-up to a temperature at which the lay-up will substantially retain its shape when the mandrel is removed, (c) removing the mandrel from the formed, chilled, hollow lay-up, (d) inserting, while still chilled, reinforcing doublers into the inboard and the outboard ends, (e) placing a matched mold about the exterior of the chilled, reinforced lay-up and forming the lay-up, under pressure to conform to the mold, (f) applying sufficient heat to the lay-up to cure the matrix and form the complex configured composite article a portion of which is not hollow.
Claim 2
Independent Claim
128 words
A method of making a composite flexbeam of complex configuration having an inboard end and an outboard end comprising: (a) forming a lay-up of fiber reinforcing material and matrix material about a rectangular mandrel, (b) chilling the lay-up to a temperature at which the lay-up will substantially retain its shape when the mandrel is removed, (c) removing the mandrel from the formed, chilled, hollow lay-up, (d) inserting, while still chilled, reinforcing doublers into the inboard and the outboard ends, (e) placing a matched mold about the exterior of the chilled, reinforced lay-up and forming the lay-up, under pressure to conform to the mold, (f) applying sufficient heat to the lay-up to cure the matrix and form the complex configured composite article a portion of which is not hollow.
Claim 3
Dependent Claim
29 words
The method of claim 1 wherein the fiber reinforcement is glass fibers, the matrix material is epoxy and the reinforcing doublers are comprised of graphite fibers and epoxy resin.
Claim 4
Independent Claim
99 words
A method of making a composite article of complex configuration comprising: (a) forming a lay-up of fiber reinforcing material and uncured matrix material about a mandrel, (b) chilling the matrix material to a temperature wherein the matrix material is no longer tacky and the mandrel is easily removed from the lay-up, (c) removing the mandrel from the lay-up, (d) placing a matched mold about the exterior of the hollow lay-up and forming the lay-up under pressure to conform to the mold, and (e) curing the matrix material to form the composite article a portion of which is not hollow.
Claim 5
Independent Claim
99 words
A method of making a composite article of complex configuration comprising: (a) forming a lay-up of fiber reinforcing material and uncured matrix material about a mandrel, (b) chilling the matrix material to a temperature wherein the matrix material is no longer tacky and the mandrel is easily removed from the lay-up, (c) removing the mandrel from the lay-up, (d) placing a matched mold about the exterior of the hollow lay-up and forming the lay-up under pressure to conform to the mold, and (e) curing the matrix material to form the composite article a portion of which is not hollow.
Claim 6
Dependent Claim
27 words
The method of claim 3 wherein said matched mold cavity describes an article having first and second substantially rigid end portions and a torsionally flexible medial portion.
Claim 7
Dependent Claim
16 words
The method of claim 4 wherein the flexible medial portion is substantially I-shaped in cross section.
Claim 8
Dependent Claim
25 words
The method of claim 5 wherein the substantially I-shaped cross-sectional medial portion is characterized by a central web of increasing thickness in longitudinally opposite directions.
Claim 9
Independent Claim
105 words
A method of making a composite article of complex configuration comprising: (a) forming a lay-up of fiber reinforcing material and uncured matrix material about a mandrel, (b) chilling the lay-up to a temperature wherein the matrix material is no longer tacky and the mandrel is easily removed from the lay-up; (c) removing the mandrel from the lay-up, (d) inserting reinforcing doublers into at least one end of the chilled hollow lay-up, (e) placing a matched mold about the exterior of the hollow lay-up and forming the lay-up, under pressure to conform to the mold, and (f) curing the matrix material to form the composite article.
Claim 10
Independent Claim
105 words
A method of making a composite article of complex configuration comprising: (a) forming a lay-up of fiber reinforcing material and uncured matrix material about a mandrel, (b) chilling the lay-up to a temperature wherein the matrix material is no longer tacky and the mandrel is easily removed from the lay-up; (c) removing the mandrel from the lay-up, (d) inserting reinforcing doublers into at least one end of the chilled hollow lay-up, (e) placing a matched mold about the exterior of the hollow lay-up and forming the lay-up, under pressure to conform to the mold, and (f) curing the matrix material to form the composite article.
Claim 11
Independent Claim
109 words
A method of making a composite article of complex configuration comprising: (a) forming a lay-up of fiber reinforcing material and uncured matrix material about a mandrel, (b) chilling the lay-up to a temperature wherein the matrix material is no longer tacky and the mandrel is easily removed from the lay-up, (c) removing the mandrel from the lay-up, (d) wrapping the chilled hollow lay-up in a layer of positioning fabric, (e) placing a matched mold about the exterior of the hollow lay-up and forming the lay-up under pressure to conform to the mold, (f) curing the matrix material to form the composite article a portion of which is not hollow.
Claim 12
Independent Claim
109 words
A method of making a composite article of complex configuration comprising: (a) forming a lay-up of fiber reinforcing material and uncured matrix material about a mandrel, (b) chilling the lay-up to a temperature wherein the matrix material is no longer tacky and the mandrel is easily removed from the lay-up, (c) removing the mandrel from the lay-up, (d) wrapping the chilled hollow lay-up in a layer of positioning fabric, (e) placing a matched mold about the exterior of the hollow lay-up and forming the lay-up under pressure to conform to the mold, (f) curing the matrix material to form the composite article a portion of which is not hollow.
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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) | 1989-05-26 | 1989-11-25 | 1990-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-05-26 | 1993-11-25 | 1994-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-05-26 | 1997-11-25 | 1998-05-27 | $7700.00 | Window Closed / Lapsed |