US3922899A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming sandwich materials
Assignee: Airbus Group SAS
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Filing: 1974-07-08
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Granted: 1975-12-02
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Expires: 1994-07-08
Abstract
Abstract The invention provides a method of forming sandwich materials. The area subjected to forming stresses is heated locally in such manner that the strength properties of the skin metals governing the permissible stress limits in that area are constantly monitored without the structure as a whole being subjected to oxidation.
Inventors
- 👤 Maurice Henri Louis Fremont
- 👤 Jean-Francois Denis
- 👤 Serve Yvan Dzalba-Lyndis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 09:09
CPC Classifications
B; B21; B21D; B21D47/00; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24149
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
103 words
A method of forming a metallic panel sandwich comprising two thin metal sheets maintained in mutually spaced relationship by a spacer element of honeycomb structure, corrugated elements, or the like, wherein the said method includes: a. placing one sheet of a metallic panel sandwich against a rotating former of rounded surface; b. applying radiant heat to the immediate proximity of points where said metallic panel sandwich is tangential to said rotating former whereby a localized and differential heating effect is provided in the two thin sheets passing thereby; and c. simultaneously rotating said former to thereby effect formation of said metallic panel sandwich.
Claim 2
Independent Claim
103 words
A method of forming a metallic panel sandwich comprising two thin metal sheets maintained in mutually spaced relationship by a spacer element of honeycomb structure, corrugated elements, or the like, wherein the said method includes: a. placing one sheet of a metallic panel sandwich against a rotating former of rounded surface; b. applying radiant heat to the immediate proximity of points where said metallic panel sandwich is tangential to said rotating former whereby a localized and differential heating effect is provided in the two thin sheets passing thereby; and c. simultaneously rotating said former to thereby effect formation of said metallic panel sandwich.
Claim 3
Dependent Claim
18 words
The method of claim 1 wherein said radiant heat is obtained from an iodine vapour or infrared-tube radiator.
Claim 4
Dependent Claim
22 words
The method of claim 1 wherein said heat is supplied from a source spaced from and not contacting said metallic panel sandwich.
Claim 5
Dependent Claim
47 words
The method of claim 1 wherein said application of radiant heat is set to provide a temperature of 770*C in one of said two sheets and a temperature of 480*C in the other of said two sheets, where said two sheets are of titanium or titanium alloys.
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) | 1978-12-01 | 1979-06-02 | 1979-12-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-01 | 1983-06-02 | 1983-12-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-01 | 1987-06-02 | 1987-12-02 | $7700.00 | Window Closed / Lapsed |