US3521066A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Railroad track alignment indicating system employing modulated infrared techniques
Assignee: FAIRMONT RAILWAY MOTORS Inc
•
Filing: 1969-02-13
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Granted: 1970-07-21
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Expires: 1989-02-13
Abstract
No abstract record available.
Inventors
- 👤 Ivan L Joy
- 👤 Charles D Johnson
- 👤 Ira Sublett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 06:17
CPC Classifications
E; E01; E01B; E01B35/00; E01B2203/00; E01B2203/16
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US830640A
Cited
US3226057A
Cited
US3000099A
Cited
US3129335A
Cited
US3298105A
Cited
US3269017A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-07-20 | 1974-01-19 | 1974-07-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-07-20 | 1978-01-19 | 1978-07-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-07-20 | 1982-01-19 | 1982-07-21 | $7700.00 | Window Closed / Lapsed |