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US3864184A Expired / Lapsed US ⏱️ 0.0 years remaining

Technique for forming laminated filamentary composites utilizing prestressing

Assignee: Northrop Grumman Systems Corp
•
Filing: 1973-08-22
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Granted: 1975-02-04
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Expires: 1993-08-22
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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)

US3127306A Cited
US3283389A Cited
US3395744A Cited
US3674581A Cited
US3682731A Cited

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

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