US2617872A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency signaling system
Assignee: Automatic Electric Laboratories Inc
•
Filing: 1949-04-02
•
Granted: 1952-11-11
•
Expires: 1969-04-02
Abstract
No abstract record available.
Inventors
- 👤 Roswell H Herrick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:13
CPC Classifications
H; H04; H04W; H04W88/00; H04W88/18; H04W88/185; H04W88/188
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1786805A
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US1904929A
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US2325829A
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US2396134A
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US2477973A
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US2485580A
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US2483445A
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US2457149A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-11-11 | 1956-05-12 | 1956-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-11-11 | 1960-05-12 | 1960-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-11-11 | 1964-05-12 | 1964-11-11 | $7700.00 | Window Closed / Lapsed |