US3885071A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fiber-reinforced epoxy composite joints
Assignee: Lockheed Martin Corp
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Filing: 1972-08-10
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Granted: 1975-05-20
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Expires: 1992-08-10
Abstract
Abstract An improved manufacture including a fiber-reinforced epoxy composite joint, and the method of producing same, in which the fibers of each of the composite adherends pass through and are intermeshed across the joint bondline. A scarfed mating surface is prepared on the end of each of the adherend elements-to-bejoined, after which a chemical etching of the mating ends to obtain exposed lengths of filaments or fibers is provided. A sheet of unsupported adhesive material is inserted between the scarfed and etched mating surfaces prior to their layup, after which heat and pressure are applied for bonding the joint. The exposed fibers of each element cross the bondline to intermesh with those of the other element during the melting of the unsupported adhesive. This process increases the joint efficiency to 83 percent of the efficiency of a non-joined element.
Inventors
- 👤 Leiv H Blad
- 👤 Robert F Warkow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:14
CPC Classifications
B; B29; B29C; B29C37/00; B29C37/0078; B29C37/0082; B32; B32B; B32B27/00; B32B27/06; B32B27/08; B29C65/00; B29C65/48; B29C65/50; B29C65/5057; B29C66/00; B29C66/01; B29C66/02; B29C66/022; B29C66/0222; B29C66/026; B29C66/05; B29C66/10; B29C66/11; B29C66/116; B29C66/1162; B29C66/14; B29C66/303; B29C66/3032; B29C66/30321; B29C66/40; B29C66/41; B29C66/43; B29C66/70; B29C66/71; B29C66/72; B29C66/721; B29C66/7214; B29C66/72141; B29C66/73; B29C66/739; B29C66/7394; B29C66/73941; B32B27/12; B32B27/38; B29C65/4805; B29C65/481; B29C65/4815; B29C65/483; B29C65/4835; B29C65/82; B29C65/8207; B29C65/8215; B29C66/001; B29C66/0012; B29C66/0014; B29C66/00145; B29C66/0224; B29C66/02245; B29C66/114; B29C66/1142; B29C66/7212; B29C66/74; B29C66/742; B29C66/90; B29C66/91; B29C66/914; B29C66/9141; B29C66/919; B29C66/92; B29C66/929; B29C66/94; B29C66/949; B29K; B29K2063/00; B29K2105/00; B29K2105/06; B29K2105/08; B29K2105/10; B29K2105/101; B29K2277/00; B29K2307/00; B29K2307/02; B29K2309/00; B29K2309/08; H; H05; H05K; H05K1/00; H05K1/02; H05K1/03; H05K1/0313; H05K1/0353; H05K1/0366; H05K1/14; H05K1/142; H05K3/00; H05K3/0011; H05K3/0017; H05K3/36; Y; Y10; Y10S; Y10S273/00; Y10S273/03; Y10S273/23; Y10T; Y10T428/00; Y10T428/19; Y10T428/192; Y10T428/195; Y10T428/249921; Y10T428/249924; Y10T428/24994; Y10T428/249942; Y10T428/249945; Y10T428/249946
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
83 words
AN IMPROVED FIBER-REINFORCED EPOXY COMPOSITE JOINT COMPRISING AT LEAST A PAIR OF FIBER-REINFORCED EPOXY COMPOSITE ADHERENDS HAVING ENDS SCARFED AND MATED IN COMPLEMENTARY RELATION TO EACH OTHER ACROSS AN UNSUPPORTED ADHESIVE, ALL BLONDED TOGETHER, EACH OS SUCH ADHERENDS HAING A PLURAITY OF LAYERS OF SUBSTANTIALLY EQUALLY EXPOSED LENGTHS OF INERT FIBERS DISPOSED WITHIN AND EXTENDING UNIDIRECTIONALLY FROM ITS SCARFED MATING SURFACE SUBSTANTIALLY PARALLED TO THE LONGITUDINAL AXIS OF THE ELEMENTS-TO-BE-JOINED AND BEING INTERMESHED WITH LIKE LENGTHS OF FIBERS EXTENDING FROM THE OTHER ADHEREND.
Claim 2
Dependent Claim
83 words
AN IMPROVED FIBER-REINFORCED EPOXY COMPOSITE JOINT COMPRISING AT LEAST A PAIR OF FIBER-REINFORCED EPOXY COMPOSITE ADHERENDS HAVING ENDS SCARFED AND MATED IN COMPLEMENTARY RELATION TO EACH OTHER ACROSS AN UNSUPPORTED ADHESIVE, ALL BLONDED TOGETHER, EACH OS SUCH ADHERENDS HAING A PLURAITY OF LAYERS OF SUBSTANTIALLY EQUALLY EXPOSED LENGTHS OF INERT FIBERS DISPOSED WITHIN AND EXTENDING UNIDIRECTIONALLY FROM ITS SCARFED MATING SURFACE SUBSTANTIALLY PARALLED TO THE LONGITUDINAL AXIS OF THE ELEMENTS-TO-BE-JOINED AND BEING INTERMESHED WITH LIKE LENGTHS OF FIBERS EXTENDING FROM THE OTHER ADHEREND.
Claim 3
Dependent Claim
33 words
The improved fiber-reinforced epoxy composite joint of claim 1 wherein said inert fibers are selected from the class of materials comprising graphite, boron, glass pitch blend, carbon, and high modulous organic fiber compositions.
Claim 4
Dependent Claim
21 words
The improved fiber-reinforced epoxy composite joint of claim 1 wherein said ends are scarfed at angles of from 4* and 6*.
References Cited (Backward Citations)
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US3431157A
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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) | 1978-05-19 | 1978-11-18 | 1979-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-19 | 1982-11-18 | 1983-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-19 | 1986-11-18 | 1987-05-20 | $7700.00 | Window Closed / Lapsed |