Patent US2472691A successfully refreshed from Google Patents.
US2472691A
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Piezoelectric crystal apparatus
Assignee: AT&T Inc
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Filing: 1946-08-16
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Granted: 1949-06-07
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Expires: 1966-08-16
Abstract
No abstract record available.
Inventors
- 👤 Walter L Bond
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:12
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/02; H03H9/02007; H03H9/02015; H03H9/02157
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-06-06 | 1952-12-06 | 1953-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-06-06 | 1956-12-06 | 1957-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-06-06 | 1960-12-06 | 1961-06-07 | $7700.00 | Window Closed / Lapsed |