US2807091A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Keyway checkers
Assignee: Individual
•
Filing: 1954-07-26
•
Granted: 1957-09-24
•
Expires: 1974-07-26
Abstract
No abstract record available.
Inventors
- 👤 Fred E Michelson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:50
CPC Classifications
G; G01; G01B; G01B5/00; G01B5/0018
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US1455083A
Cited
US2494152A
Cited
US2522886A
Cited
US2569873A
Cited
US2650437A
Cited
US2677894A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-09-23 | 1961-03-25 | 1961-09-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-09-23 | 1965-03-25 | 1965-09-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-09-23 | 1969-03-25 | 1969-09-24 | $7700.00 | Window Closed / Lapsed |