Patent US2628435A successfully refreshed from Google Patents.
US2628435A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Educational device
Assignee: Individual
•
Filing: 1949-08-13
•
Granted: 1953-02-17
•
Expires: 1969-08-13
Abstract
No abstract record available.
Inventors
- 👤 Frank M Minninger
- 👤 Evelyn S Minninger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 19:08
CPC Classifications
G; G09; G09B; G09B17/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1023586A
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US1120681A
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US1286157A
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US1445819A
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US1538530A
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GB238060A
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US2213411A
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US2336742A
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US2361154A
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US2477134A
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US2449116A
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US2453265A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-02-17 | 1956-08-18 | 1957-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-02-17 | 1960-08-18 | 1961-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-02-17 | 1964-08-18 | 1965-02-17 | $7700.00 | Window Closed / Lapsed |