US2564258A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multiple annular heat transfer element forced flow air heater
Assignee: 8600 DENISON Co
•
Filing: 1950-04-21
•
Granted: 1951-08-14
•
Expires: 1970-04-21
Abstract
No abstract record available.
Inventors
- 👤 George B Herbster
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 05:48
CPC Classifications
F; F24; F24H; F24H3/00; F24H3/02; F24H3/06; F24H3/065
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
FR530879A
Cited
US2135089A
Cited
US2153120A
Cited
US2277247A
Cited
US2307586A
Cited
US2314825A
Cited
US2370309A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-08-13 | 1955-02-12 | 1955-08-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-08-13 | 1959-02-12 | 1959-08-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-08-13 | 1963-02-12 | 1963-08-14 | $7700.00 | Window Closed / Lapsed |