Patent US2938377A successfully refreshed from Google Patents.
US2938377A
Expired / Lapsed
US
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Hardness testers
Assignee: Torsion Balance Co
•
Filing: 1951-09-13
•
Granted: 1960-05-31
•
Expires: 1971-09-13
Abstract
No abstract record available.
Inventors
- 👤 David F Sklar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:19
CPC Classifications
G; G01; G01N; G01N3/00; G01N3/40; G01N3/42; G01N3/44
Claims Analysis
Total Claims: 0
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-05-31 | 1963-11-30 | 1964-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-05-31 | 1967-11-30 | 1968-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-05-31 | 1971-11-30 | 1972-05-31 | $7700.00 | Window Closed / Lapsed |