US3445172A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fail-safe system
Assignee: American Gas Association Inc
•
Filing: 1967-08-02
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Granted: 1969-05-20
•
Expires: 1987-08-02
Abstract
No abstract record available.
Inventors
- 👤 Robert J Zielinski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 05:26
CPC Classifications
F; F23; F23N; F23N5/00; F23N5/02; F23N5/12; F23N5/123; F23N2231/00; F23N2231/16
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3174528A
Cited
US2270722A
Cited
US2248737A
Cited
US3273019A
Cited
US3238992A
Cited
US3348104A
Cited
US3364971A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-05-19 | 1972-11-18 | 1973-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-05-19 | 1976-11-18 | 1977-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-05-19 | 1980-11-18 | 1981-05-20 | $7700.00 | Window Closed / Lapsed |