US2541121A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for testing electric heating devices
Assignee: BIRTMAN ELECTRIC Co
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Filing: 1946-11-09
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Granted: 1951-02-13
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Expires: 1966-11-09
Abstract
No abstract record available.
Inventors
- 👤 Charles H Sparklin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:56
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/327; G01R31/3277
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) | 1954-02-12 | 1954-08-14 | 1955-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-02-12 | 1958-08-14 | 1959-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-02-12 | 1962-08-14 | 1963-02-13 | $7700.00 | Window Closed / Lapsed |