US1820922A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Relay and meter testing and calibrating switch
Assignee: ELECTRIC PROGRESS Co Inc
•
Filing: 1930-06-13
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Granted: 1931-09-01
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Expires: 1950-06-13
Abstract
No abstract record available.
Inventors
- 👤 Sporn Philip
- 👤 Henry D Freitag
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:51
CPC Classifications
A; A43; A43B; A43B13/00; A43B13/02; A43B13/08; A43B13/14; A43B13/141; H; H01; H01H; H01H21/00; H01H21/54; H01H21/58
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) | 1934-08-31 | 1935-03-02 | 1935-09-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1938-08-31 | 1939-03-02 | 1939-09-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1942-08-31 | 1943-03-02 | 1943-09-01 | $7700.00 | Window Closed / Lapsed |