US3476180A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Studded heat exchanger tubes
Assignee: ExxonMobil Technology and Engineering Co
•
Filing: 1967-06-30
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Granted: 1969-11-04
•
Expires: 1987-06-30
Abstract
No abstract record available.
Inventors
- 👤 Harry E Straight Jr
- 👤 John A Kivlen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:26
CPC Classifications
F; F28; F28F; F28F1/00; F28F1/10; F28F1/12; F28F1/124; F22; F22B; F22B37/00; F22B37/02; F22B37/10; F22B37/106
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
FR743795A
Cited
US1390783A
Cited
US1521864A
Cited
US1942211A
Cited
FR827519A
Cited
GB545608A
Cited
US3163153A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-11-03 | 1973-05-05 | 1973-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-11-03 | 1977-05-05 | 1977-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-11-03 | 1981-05-05 | 1981-11-04 | $7700.00 | Window Closed / Lapsed |