US2451227A
Expired / Lapsed
US
⏱️ 0.0 years remaining
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Assignee: Individual
•
Filing: 1944-10-23
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Granted: 1948-10-12
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Expires: 1964-10-23
Abstract
No abstract record available.
Inventors
- 👤 Norman R Krause
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 06:26
CPC Classifications
F; F02; F02M; F02M35/00; F02M35/02; F02M35/08; Y; Y10; Y10T; Y10T137/00; Y10T137/794; Y10T137/7976; Y10T137/8085; Y10T137/8593; Y10T137/877; Y10T137/87788; Y10T137/87812
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) | 1951-10-12 | 1952-04-12 | 1952-10-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-10-12 | 1956-04-12 | 1956-10-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-10-12 | 1960-04-12 | 1960-10-12 | $7700.00 | Window Closed / Lapsed |