Patent US2813699A successfully refreshed from Google Patents.
US2813699A
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Pebble heater apparatus
Assignee: Phillips Petroleum Co
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Filing: 1953-03-09
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Granted: 1957-11-19
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Expires: 1973-03-09
Abstract
No abstract record available.
Inventors
- 👤 Robert L Mcintire
- 👤 John W Begley
- 👤 Louis C Bearer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:19
CPC Classifications
F; F28; F28C; F28C3/00; F28C3/10; F28C3/12; F28C3/14
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2636805A
Cited
US2101490A
Cited
US2441335A
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US2446986A
Cited
US2451924A
Cited
US2530274A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-11-18 | 1961-05-20 | 1961-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-11-18 | 1965-05-20 | 1965-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-11-18 | 1969-05-20 | 1969-11-19 | $7700.00 | Window Closed / Lapsed |