US3886024A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thick-walled, fiber-reinforced composite structures and method of making same
Assignee: Whittaker Corp
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Filing: 1972-10-12
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Granted: 1975-05-27
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Expires: 1992-10-12
Abstract
Abstract Residual internal stresses in thick-walled, fiber-reinforced composite structures are minimized by fabricating the latter from a plurality of cured, thin-walled, fiber-reinforced shells in which the resin is a high temperature curing resin and which are telescoped together and bonded to each other at low temperatures using low temperature curing adhesive. The thin-walled shells may be unitary structures or they may be built up from segments. The shells are preferably tapered in their longitudinal direction when making long structures.
Inventors
- 👤 Vance A Chase
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:43
CPC Classifications
F; F16; F16L; F16L9/00; F16L9/12; F16L9/121; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/1352; Y10T428/1372
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
168 words
A method of making a thick-walled, fiber-reinforced composite structure comprising the steps of: fabricating a plurality of thin-walled, fiber-reinforced resin shells of differing diameter such that said shells, when cured, can be telescoped together to produce a thick-walled structure, said resin in said shells being a high temperature curing resin selected from the group consisting of epoxy, phenolic and polyimide resins, each said shell having a thickness substantially less than the diameter of said thick-walled, composite structure and not being greater than about 0.250 in.; curing said thin-walled shells at the cure temperature for said resin; interposing a low temperature curing epoxy adhesive between confronting surfaces of said cured shells so that the walls of said cured shells alternate with said adhesive when said cured shells are telescoped together; telescoping said cured shells together to build up a thick-walled composite structure; and curing said adhesive at a temperature within its low temperature curing range to thereby bond said cured shells together to produce a cured, thick-walled composite structure.
Claim 2
Independent Claim
168 words
A method of making a thick-walled, fiber-reinforced composite structure comprising the steps of: fabricating a plurality of thin-walled, fiber-reinforced resin shells of differing diameter such that said shells, when cured, can be telescoped together to produce a thick-walled structure, said resin in said shells being a high temperature curing resin selected from the group consisting of epoxy, phenolic and polyimide resins, each said shell having a thickness substantially less than the diameter of said thick-walled, composite structure and not being greater than about 0.250 in.; curing said thin-walled shells at the cure temperature for said resin; interposing a low temperature curing epoxy adhesive between confronting surfaces of said cured shells so that the walls of said cured shells alternate with said adhesive when said cured shells are telescoped together; telescoping said cured shells together to build up a thick-walled composite structure; and curing said adhesive at a temperature within its low temperature curing range to thereby bond said cured shells together to produce a cured, thick-walled composite structure.
Claim 3
Dependent Claim
72 words
The method of claim 1 wherein at least one of said thin-walled shells is radially segmented, said segmented shell(s) being formed by: fabricating a plurality of thin-walled, fiber-reinforced, radially arcuate segments which, when radially assembled together, form a shell; curing each said segment at the cure temperature for said high temperature-curing resin; and applying a low temperature curing adhesive between confronting surfaces of said cured segments when assembled in a shell pattern.
Claim 4
Dependent Claim
20 words
The method of claim 2 wherein said composite structure is made by alternating segmented, thin-walled shells with non-segmented, thin-walled shells.
Claim 5
Dependent Claim
51 words
The method of claim 2 including, in addition: fabricating said segments to provide them with a longitudinal taper such that when said segments are paired in over-lapping relationship, they form a shell wall of substantially uniform thickness; and applying a low temperature curing adhesive to confronting surfaces of said paired segments.
Claim 6
Dependent Claim
51 words
The method of claim 1 wherein said shells are provided with a longitudinal taper so that each pair of said tapered shells forms a thin-walled shell of substantially uniform thickness when paired in overlapping relation and wherein confronting surfaces of said tapered shells are coated with a low temperature curing adhesive.
Claim 7
Dependent Claim
38 words
The method of claim 1 wherein said high temperature curing resin is curable in the temperature range between about 300*F and about 350*F and wherein said low temperature curing adhesive is curable at a temperature below about 150*F.
Claim 8
Dependent Claim
112 words
S METHOD OF MAKING A THICK-WALLED, FIBER-REINFORCED COMPOSITE STRUCTURE COMPRISING THE STEPS OF: FABRICATING A PLURALITY OF THIN-WALLED, FIBER-REINFORCED RESIN SHELLS OF DIFFERING DIAMETER SUCH THAT SAID SHELLS, WHEN CURED, CAN BE TELESCOPED TOGETHER TO PRODUCE A THICKWALLED STRUCTURE, SAID RESIN IN SAID SHELLS BEING A HIGH TEMPERATURE CURING RESIN CURABLE AT A TEMPERATURE BETWEEN ABOUT 300*F AND ABOUT 350*F, EACH SAID SHELL HAVING A THICKNESS SUBSTANTIALLY LESS THAN THE DIAMETER OF SAID THICK-WALLED COMPOSITE STRUCTURE AND NOT BEING GREATER THAN ABOUT 0.250 IN.; CURING SAID THIN-WALLED SHELLS AT THE CURE TEMPERATURE FOR SAID RESIN; INTERPOSING A LOW TEMPERATURE CURING ADHESIVE BETWEEN CONFRONTING SURFACES OF SAID CURED SHELLS SO THAT THE WALLS
Claim 9
Dependent Claim
112 words
S METHOD OF MAKING A THICK-WALLED, FIBER-REINFORCED COMPOSITE STRUCTURE COMPRISING THE STEPS OF: FABRICATING A PLURALITY OF THIN-WALLED, FIBER-REINFORCED RESIN SHELLS OF DIFFERING DIAMETER SUCH THAT SAID SHELLS, WHEN CURED, CAN BE TELESCOPED TOGETHER TO PRODUCE A THICKWALLED STRUCTURE, SAID RESIN IN SAID SHELLS BEING A HIGH TEMPERATURE CURING RESIN CURABLE AT A TEMPERATURE BETWEEN ABOUT 300*F AND ABOUT 350*F, EACH SAID SHELL HAVING A THICKNESS SUBSTANTIALLY LESS THAN THE DIAMETER OF SAID THICK-WALLED COMPOSITE STRUCTURE AND NOT BEING GREATER THAN ABOUT 0.250 IN.; CURING SAID THIN-WALLED SHELLS AT THE CURE TEMPERATURE FOR SAID RESIN; INTERPOSING A LOW TEMPERATURE CURING ADHESIVE BETWEEN CONFRONTING SURFACES OF SAID CURED SHELLS SO THAT THE WALLS
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) | 1978-05-26 | 1978-11-25 | 1979-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-26 | 1982-11-25 | 1983-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-26 | 1986-11-25 | 1987-05-27 | $7700.00 | Window Closed / Lapsed |