US4155970A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for making a hollow composite using a destructible core
Assignee: McDonnell Douglas Corp
•
Filing: 1977-11-04
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Granted: 1979-05-22
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Expires: 1997-11-04
Abstract
Abstract A method of making a high temperature fluted core composite radome structure.
Inventors
- 👤 George J. Cassell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:33
CPC Classifications
H; H01; H01Q; H01Q1/00; H01Q1/42; B; B29; B29C; B29C33/00; B29C33/44; B29C33/52; B29C61/00; B29C61/02; B29C70/00; B29C70/04; B29C70/28; B29C70/30; B29D; B29D22/00; B29D24/00; B29D24/002; B29D24/008; B29K; B29K2105/00; B29K2105/06; B29L; B29L2031/00; B29L2031/34; B29L2031/3456; Y; Y10; Y10S; Y10S428/00; Y10S428/913; Y10T; Y10T428/00; Y10T428/13; Y10T428/131; Y10T428/1314; Y10T428/29; Y10T428/2913; Y10T428/2933; Y10T428/2935; Y10T428/2936; Y10T428/31504; Y10T428/31551; Y10T428/31623
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
116 words
A method for making a hollow composite structure comprising the steps of: forming a meltable mandrel with fixed rectangular cross section; enclosing the mandrel with an inert heat shrinkable material; heating the inert heat shrinkable material to shrink it tightly around the mandrel; covering the enclosed mandrel with fiber reinforcing material; impregnating the fiber reinforcement with curable binder; curing the binder in the fiber reinforcing material, thereby forming said hollow composite structure; venting the meltable mandrel; melting the mandrel with heat and removing the melted mandrel from the heat shrinkable material; then additionally heating the heat shrinkable material to reduce its cross-sectional area; and removing the heat shrinkable material from inside of the hollow composite structure.
Claim 2
Independent Claim
116 words
A method for making a hollow composite structure comprising the steps of: forming a meltable mandrel with fixed rectangular cross section; enclosing the mandrel with an inert heat shrinkable material; heating the inert heat shrinkable material to shrink it tightly around the mandrel; covering the enclosed mandrel with fiber reinforcing material; impregnating the fiber reinforcement with curable binder; curing the binder in the fiber reinforcing material, thereby forming said hollow composite structure; venting the meltable mandrel; melting the mandrel with heat and removing the melted mandrel from the heat shrinkable material; then additionally heating the heat shrinkable material to reduce its cross-sectional area; and removing the heat shrinkable material from inside of the hollow composite structure.
Claim 3
Dependent Claim
10 words
Method of claim 1 wherein the meltable mandrel is lead.
Claim 4
Dependent Claim
14 words
Method of claim 2 wherein the heat shrinkable material is a Teflon shrink tube.
Claim 5
Dependent Claim
21 words
The method of claim 3 including applying facing sheets of binder impregnated fabric to opposite sides of the fiber covered mandrel.
Claim 6
Dependent Claim
12 words
Method of claim 4 wherein the binder is a polyimide resinous material.
Claim 7
Dependent Claim
15 words
Method of claim 5 wherein the fiber reinforcement is a glass or fused silica material.
References Cited (Backward Citations)
US3126680A
Cited
US1504547A
Cited
US2345977A
Cited
US2755216A
Cited
US3225129A
Cited
US3795559A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-05-21 | 1982-11-20 | 1983-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-05-21 | 1986-11-20 | 1987-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-05-21 | 1990-11-20 | 1991-05-22 | $7700.00 | Window Closed / Lapsed |