US3864184A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Technique for forming laminated filamentary composites utilizing prestressing
Assignee: Northrop Grumman Systems Corp
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Filing: 1973-08-22
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Granted: 1975-02-04
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Expires: 1993-08-22
Abstract
Abstract Strips or sheets of material comprising filaments impregnated in a binder material are stressed in a stressing machine to a sufficient degree to cuase a number of the filaments to break. The strips or sheets are then layered and molded together to form a laminated composite. The composite material so formed is found to have significantly improved structural characteristics.
Inventors
- 👤 Walter E Crandall
- 👤 George J Mills
- 👤 Gary G Brown
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:23
CPC Classifications
B; B29; B29C; B29C70/00; B29C70/04; B29C70/28; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24058
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
58 words
A TECHNIQUE FOR FABRICATING FIBERED LAMINATED COMPOSITES FROM A PLURALITY OF SECTIONS FORMED OF SIMILAR TYPE OF LOAD BEARING FILAMENTS IMPREGANTED WITH A MATRIX MATERIAL COMPRISING THE STEPS OF: STRESSING EACH OF SAID SECTIONS UNTIL A NUMBER OF THE FILAMENTS THEREOF ARE BROKEN, LAYERING SAID SECTIONS AGAINST EACH OTHER, AND MOLDING SAID LAYERED SECTIONS INTO A LAMINATED COMPOSITE.
Claim 2
Dependent Claim
58 words
A TECHNIQUE FOR FABRICATING FIBERED LAMINATED COMPOSITES FROM A PLURALITY OF SECTIONS FORMED OF SIMILAR TYPE OF LOAD BEARING FILAMENTS IMPREGANTED WITH A MATRIX MATERIAL COMPRISING THE STEPS OF: STRESSING EACH OF SAID SECTIONS UNTIL A NUMBER OF THE FILAMENTS THEREOF ARE BROKEN, LAYERING SAID SECTIONS AGAINST EACH OTHER, AND MOLDING SAID LAYERED SECTIONS INTO A LAMINATED COMPOSITE.
Claim 3
Dependent Claim
23 words
The process of claim 1 wherein said sections are molded into a composite by simultaneously applying heat and pressure to the layered structure.
Claim 4
Dependent Claim
16 words
The technique of claim 1 wherein said layered sections comprise boron filaments impregnated with epoxy resin.
Claim 5
Dependent Claim
16 words
The technique of claim 1 wherein said layered sections comprise boron filaments impregnated with polyimide resin.
Claim 6
Dependent Claim
18 words
The process of claim 1 wherein said sections are stressed until approximately half the filaments thereof are broken.
Claim 7
Dependent Claim
16 words
The technique of claim 1 wherein said layered sections comprise graphite filaments impregnated with epoxy resin.
Claim 8
Dependent Claim
37 words
The technique of claim 1 wherein said sections are cut from a tape, said tape being stressed in a stressing machine over rollers having a predetermined radius by the application of a predetermined load to said tape.
Claim 9
Dependent Claim
20 words
The technique of claim 1 wherein said sections are stressed until approximately 12 percent of the filaments thereof are broken.
Claim 10
Dependent Claim
73 words
A TECHNIQUE FOR FABRICATING SECTIONS FORMED OF SIMILARLY TYPE OF LOAD BEARING FILAMENTS IMPREGNATED WITH A MATRIX MATERIAL FOR USE IN MAKING A LAMINATED COMPOSITE FORMED FROM A PLURALITY OF SUCH SECTIONS LAYERED AGAINST EACH OTHER AND MOLDED TOGETHER COMPRISING: STRESSING EACH OF SAID SECTIONS AND ALL OF THE FILAMENTS THEREOF UNIFORMLY WITH A PREDETERMINED FORCE SUCH AS TO BREAK A NUMBER OF THE WEAKER FILAMENTS AND TO LEAVE THE STRONGER FILAMENTS UNBROKEN.
Claim 11
Dependent Claim
73 words
A TECHNIQUE FOR FABRICATING SECTIONS FORMED OF SIMILARLY TYPE OF LOAD BEARING FILAMENTS IMPREGNATED WITH A MATRIX MATERIAL FOR USE IN MAKING A LAMINATED COMPOSITE FORMED FROM A PLURALITY OF SUCH SECTIONS LAYERED AGAINST EACH OTHER AND MOLDED TOGETHER COMPRISING: STRESSING EACH OF SAID SECTIONS AND ALL OF THE FILAMENTS THEREOF UNIFORMLY WITH A PREDETERMINED FORCE SUCH AS TO BREAK A NUMBER OF THE WEAKER FILAMENTS AND TO LEAVE THE STRONGER FILAMENTS UNBROKEN.
Claim 12
Dependent Claim
16 words
The technique of claim 9 wherein said layered sections comprise boron filaments impregnated with epoxy resin.
Claim 13
Dependent Claim
16 words
The technique of claim 9 wherein said layered sections comprise boron filaments impregnated with polyimide resin.
Claim 14
Dependent Claim
18 words
The process of claim 9 wherein said sections are stressed until approximately half the filaments thereof are broken.
Claim 15
Dependent Claim
16 words
The technique of claim 9 wherein said layered sections comprise graphite filaments impregnated with epoxy resin.
Claim 16
Dependent Claim
37 words
The technique of claim 9 wherein said sections are cut from a tape, said tape being stressed in a stressing machine over rollers having a predetermined radius by the application of a predetermined load to said tape.
Claim 17
Dependent Claim
20 words
The technique of claim 9 wherein said sections are stressed until approximately 12 percent of the filaments thereof are broken.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-02-03 | 1978-08-05 | 1979-02-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-03 | 1982-08-05 | 1983-02-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-03 | 1986-08-05 | 1987-02-04 | $7700.00 | Window Closed / Lapsed |