US2540141A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Longitudinal seam for corrugated metal pipe for light duty tunnel liners
Assignee: Armco Inc
•
Filing: 1946-03-06
•
Granted: 1951-02-06
•
Expires: 1966-03-06
Abstract
No abstract record available.
Inventors
- 👤 George E Shafer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:06
CPC Classifications
E; E21; E21D; E21D11/00; E21D11/14; E21D11/15; F; F16; F16L; F16L9/00; F16L9/22
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US181297A
Cited
US613053A
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US915086A
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US934574A
Cited
US970772A
Cited
US1140362A
Cited
US1232043A
Cited
US1208708A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-02-05 | 1954-08-07 | 1955-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-02-05 | 1958-08-07 | 1959-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-02-05 | 1962-08-07 | 1963-02-06 | $7700.00 | Window Closed / Lapsed |