US2828946A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air heater
Assignee: EIDP Inc
•
Filing: 1954-12-29
•
Granted: 1958-04-01
•
Expires: 1974-12-29
Abstract
No abstract record available.
Inventors
- 👤 William J Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:33
CPC Classifications
F; F28; F28D; F28D9/00; F28D9/0012; F28D9/0018; Y; Y10; Y10S; Y10S165/00; Y10S165/051; Y10S165/052; Y10S165/07
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) | 1961-03-31 | 1961-09-30 | 1962-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-03-31 | 1965-09-30 | 1966-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-03-31 | 1969-09-30 | 1970-04-01 | $7700.00 | Window Closed / Lapsed |