Patent US2920340A successfully refreshed from Google Patents.
US2920340A
Expired / Lapsed
US
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Hinge means for a self-closing, gravityactuated door panel
Assignee: National Manufacturing Co
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Filing: 1956-06-25
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Granted: 1960-01-12
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Expires: 1976-06-25
Abstract
No abstract record available.
Inventors
- 👤 Edward H Hopkins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:22
CPC Classifications
E; E05; E05F; E05F1/00; E05F1/02; E05F1/04; E05F1/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US353962A
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US373837A
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US557473A
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US1312667A
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US1225899A
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US1327045A
Cited
US1583084A
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US1393190A
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US2603825A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-01-11 | 1963-07-13 | 1964-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-01-11 | 1967-07-13 | 1968-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-01-11 | 1971-07-13 | 1972-01-12 | $7700.00 | Window Closed / Lapsed |