US3271269A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control system for fractional distillation
Assignee: Phillips Petroleum Co
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Filing: 1961-12-26
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Granted: 1966-09-06
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Expires: 1981-12-26
Abstract
No abstract record available.
Inventors
- 👤 Harry L Walker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:17
CPC Classifications
B; B01; B01D; B01D3/00; B01D3/42; B01D3/4211; B01D3/4233
Claims Analysis
Total Claims: 0
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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) | 1969-09-05 | 1970-03-07 | 1970-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-09-05 | 1974-03-07 | 1974-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-09-05 | 1978-03-07 | 1978-09-06 | $7700.00 | Window Closed / Lapsed |