US3718113A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Buried pipeline signal
Assignee: 3M Co
•
Filing: 1970-07-13
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Granted: 1973-02-27
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Expires: 1990-07-13
Abstract
Abstract A BURIED VISUAL WARNING DEVICE CAPABLE OF PRODUCING A RISABLE VISIBLE SIGNAL, COMPRISING AN UNDERGROUND CORROSION-RESISTANT, FLEXIBLE, RUPTURABLE, ESSENTIALLY MOISTURE AND OXYGEN PROOF TUBULAR MEMBER CONTAINING A VISUAL SIGNAL PRODUCING MEANS RELEASED INTO THE AIR UPON RUPTURE OF THE TUBULAR MEMBER. ALSO CONTEMPLATED IS THE USE OF A PLURALITY OF THE WARNING DEVICES IN SPACED PROTECTIVE RELATIONSHIP ABOUT AND PARALLEL TO A UTILITY CONDUIT. D R A W I N G
Inventors
- 👤 P Schertler
- 👤 R Strobel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:37
CPC Classifications
H; H02; H02G; H02G9/00; F; F16; F16L; F16L1/00; F16L1/024; F16L1/06; F16L1/11; F16L55/00; F17; F17D; F17D5/00; F17D5/02; H02G9/02; H02G9/025; Y; Y10; Y10S; Y10S116/00; Y10S116/14
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-27 | 1976-08-28 | 1977-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-27 | 1980-08-28 | 1981-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-27 | 1984-08-28 | 1985-02-27 | $7700.00 | Window Closed / Lapsed |