US2907832A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Crossbar relay private branch exchange telephone system
Assignee: LEICH ELECTRIC CO
•
Filing: 1957-02-28
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Granted: 1959-10-06
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Expires: 1977-02-28
Abstract
No abstract record available.
Inventors
- 👤 Hans P Boswau
- 👤 Robert V Oldham
- 👤 Harry G Evers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 06:12
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/0004
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) | 1962-10-05 | 1963-04-06 | 1963-10-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-10-05 | 1967-04-06 | 1967-10-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-10-05 | 1971-04-06 | 1971-10-06 | $7700.00 | Window Closed / Lapsed |