Patent US2173589A successfully refreshed from Google Patents.
US2173589A
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Piezoelectric apparatus
Assignee: AT&T Inc
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Filing: 1933-12-14
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Granted: 1939-09-19
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Expires: 1953-12-14
Abstract
No abstract record available.
Inventors
- 👤 Warren P Mason
- 👤 Roger A Sykes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 22:16
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/02; H03H9/02007; H03H9/02015; H03H9/02023; H03H9/02086; H03H9/02133; H03H9/05; H03H9/0504
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1942-09-18 | 1943-03-20 | 1943-09-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-09-18 | 1947-03-20 | 1947-09-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-09-18 | 1951-03-20 | 1951-09-19 | $7700.00 | Window Closed / Lapsed |