US2716975A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Combustion type air heater for drying purposes
Assignee: HARTZELL INDUSTRIES
•
Filing: 1951-11-14
•
Granted: 1955-09-06
•
Expires: 1971-11-14
Abstract
No abstract record available.
Inventors
- 👤 Danal W Johnston
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 18:20
CPC Classifications
F; F26; F26B; F26B21/00; F26B21/001
Claims Analysis
Total Claims: 0
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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) | 1958-09-05 | 1959-03-07 | 1959-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-09-05 | 1963-03-07 | 1963-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-09-05 | 1967-03-07 | 1967-09-06 | $7700.00 | Window Closed / Lapsed |