US2580757A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alarm sending circuit
Assignee: AT&T Inc
•
Filing: 1948-10-29
•
Granted: 1952-01-01
•
Expires: 1968-10-29
Abstract
No abstract record available.
Inventors
- 👤 Charles E Germanton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:50
CPC Classifications
H; H04; H04Q; H04Q1/00; H04Q1/18; H04Q1/20; H04Q1/22; H04Q1/26
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1610346A
Cited
US1616738A
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US1569678A
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US1708946A
Cited
US1805726A
Cited
GB391857A
Cited
US1912450A
Cited
US1899112A
Cited
US2262595A
Cited
US2268635A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-12-31 | 1955-07-02 | 1956-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-12-31 | 1959-07-02 | 1960-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-12-31 | 1963-07-02 | 1964-01-01 | $7700.00 | Window Closed / Lapsed |