US2859540A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical educational device
Assignee: Individual
•
Filing: 1955-05-20
•
Granted: 1958-11-11
•
Expires: 1975-05-20
Abstract
No abstract record available.
Inventors
- 👤 Walter S Himpele
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:15
CPC Classifications
G; G09; G09B; G09B23/00; G09B23/06; G09B23/18; G09B23/183; G09B23/185
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US405572A
Cited
US1911243A
Cited
US2256862A
Cited
US2592552A
Cited
US2610229A
Cited
US2611008A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-11-10 | 1962-05-12 | 1962-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-11-10 | 1966-05-12 | 1966-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-11-10 | 1970-05-12 | 1970-11-11 | $7700.00 | Window Closed / Lapsed |