US2516093A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat pump water heater and method of heat exchange
Assignee: V C Patterson & Associates Inc
•
Filing: 1949-05-05
•
Granted: 1950-07-18
•
Expires: 1969-05-05
Abstract
No abstract record available.
Inventors
- 👤 Alonzo W Ruff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 01:41
CPC Classifications
F; F24; F24H; F24H4/00; F24H4/02; F24H4/04; F25; F25B; F25B30/00; F25B30/02; F25B2339/00; F25B2339/04; F25B2339/047; F25B2400/00; F25B2400/04; F25B2400/0411; F25B2400/0415; F25B2400/07; F25B2400/071; F25B40/00; F25B40/02; F25B40/04
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) | 1953-07-17 | 1954-01-16 | 1954-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-07-17 | 1958-01-16 | 1958-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-07-17 | 1962-01-16 | 1962-07-18 | $7700.00 | Window Closed / Lapsed |