US2349987A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signal system using phase modulation
Assignee: Hitachi Rail STS USA Inc
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Filing: 1942-01-12
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Granted: 1944-05-30
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Expires: 1962-01-12
Abstract
No abstract record available.
Inventors
- 👤 Willard P Place
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:52
CPC Classifications
B; B61; B61L; B61L3/00; B61L3/16; B61L3/22; B61L3/221
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) | 1947-05-30 | 1947-11-29 | 1948-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1951-05-30 | 1951-11-29 | 1952-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1955-05-30 | 1955-11-29 | 1956-05-30 | $7700.00 | Window Closed / Lapsed |