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US2540339A
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Assignee: Individual
•
Filing: 1948-06-14
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Granted: 1951-02-06
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Expires: 1968-06-14
Abstract
No abstract record available.
Inventors
- 👤 Richard W Kritzer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 11:39
CPC Classifications
F; F28; F28F; F28F1/00; F28F1/10; F28F1/12; F28F1/24; F28F1/32; F28F1/325; F28F2215/00; F28F2215/12; Y; Y10; Y10S; Y10S165/00; Y10S165/454; Y10S165/495; Y10S165/497; Y10S165/498
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) | 1954-02-05 | 1954-08-07 | 1955-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-02-05 | 1958-08-07 | 1959-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-02-05 | 1962-08-07 | 1963-02-06 | $7700.00 | Window Closed / Lapsed |