US2531895A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical system
Assignee: International Business Machines Corp
•
Filing: 1945-05-09
•
Granted: 1950-11-28
•
Expires: 1965-05-09
Abstract
No abstract record available.
Inventors
- 👤 Orville B Shafer
- 👤 John J Sullivan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:10
CPC Classifications
H; H01; H01J; H01J17/00; H01J17/02; H01J17/30; H01J17/50; H01J17/52; H01J17/54; H01J17/56; H03; H03K; H03K17/00; H03K17/51; H03K17/52
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1365157A
Cited
US1577846A
Cited
US1661579A
Cited
US2104128A
Cited
US2250874A
Cited
US2183399A
Cited
US2269442A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-11-27 | 1954-05-29 | 1954-11-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-11-27 | 1958-05-29 | 1958-11-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-11-27 | 1962-05-29 | 1962-11-28 | $7700.00 | Window Closed / Lapsed |