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US2491667A
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US
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Hardness tester
Assignee: American Machine and Metals Inc
•
Filing: 1945-11-15
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Granted: 1949-12-20
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Expires: 1965-11-15
Abstract
No abstract record available.
Inventors
- 👤 Carleton V Kent
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:56
CPC Classifications
G; G01; G01N; G01N3/00; G01N3/40; G01N3/42
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
DE503072C
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US1371458A
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US1875134A
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US2217388A
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US2243235A
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US2349989A
Cited
US2335235A
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US2406451A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-12-19 | 1953-06-20 | 1953-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-12-19 | 1957-06-20 | 1957-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-12-19 | 1961-06-20 | 1961-12-20 | $7700.00 | Window Closed / Lapsed |