US3220401A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radiant heating units
Assignee: Hazen Engineering Co
•
Filing: 1962-05-21
•
Granted: 1965-11-30
•
Expires: 1982-05-21
Abstract
No abstract record available.
Inventors
- 👤 Robert L Jones
- 👤 Howard H Nichols
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:51
CPC Classifications
F; F23; F23C; F23C3/00; F23C3/002
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2041313A
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GB502112A
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US2201385A
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US2255540A
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GB537657A
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US2504592A
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GB779669A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-11-29 | 1969-05-31 | 1969-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-11-29 | 1973-05-31 | 1973-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-11-29 | 1977-05-31 | 1977-11-30 | $7700.00 | Window Closed / Lapsed |