US2539561A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Piezoelectric crystal lapping apparatus
Assignee: Individual
•
Filing: 1946-12-13
•
Granted: 1951-01-30
•
Expires: 1966-12-13
Abstract
No abstract record available.
Inventors
- 👤 John M Wolfskill
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:21
CPC Classifications
B; B24; B24B; B24B37/00; B24B37/04; B24B37/07; B24B37/10; B24B37/105; B24B37/005
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US1147830A
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US1262529A
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US1957299A
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US2023494A
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GB497962A
Cited
US2340843A
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US2353171A
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US2404282A
Cited
US2419033A
Cited
US2423118A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-01-29 | 1954-07-31 | 1955-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-01-29 | 1958-07-31 | 1959-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-01-29 | 1962-07-31 | 1963-01-30 | $7700.00 | Window Closed / Lapsed |