Patent US1920567A successfully refreshed from Google Patents.
US1920567A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heating system
Assignee: Paper Patents Co
•
Filing: 1930-04-03
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Granted: 1933-08-01
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Expires: 1950-04-03
Abstract
No abstract record available.
Inventors
- 👤 Daniel H Keck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:21
CPC Classifications
D; D21; D21F; D21F5/00; D21F5/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1936-07-31 | 1937-01-30 | 1937-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1940-07-31 | 1941-01-30 | 1941-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1944-07-31 | 1945-01-30 | 1945-08-01 | $7700.00 | Window Closed / Lapsed |