Patent US2981147A successfully refreshed from Google Patents.
US2981147A
Expired / Lapsed
US
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Apparatus for forming contour lines
Assignee: LANGE INSTR Co
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Filing: 1955-06-02
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Granted: 1961-04-25
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Expires: 1975-06-02
Abstract
No abstract record available.
Inventors
- 👤 Willis M Carter
- 👤 Karl O Lange
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:08
CPC Classifications
G; G02; G02B; G02B21/00; G02B21/0004; G02B21/0016
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1546636A
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US1719483A
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US2163125A
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US2163124A
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US2244687A
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US2350796A
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US2703755A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-04-24 | 1964-10-24 | 1965-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-04-24 | 1968-10-24 | 1969-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-04-24 | 1972-10-24 | 1973-04-25 | $7700.00 | Window Closed / Lapsed |