US2561084A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Piezoelectric microphone
Assignee: George W Borg Corp
•
Filing: 1946-05-01
•
Granted: 1951-07-17
•
Expires: 1966-05-01
Abstract
No abstract record available.
Inventors
- 👤 Parker B Wickham
- 👤 Samuel A Johnston
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:41
CPC Classifications
H; H04; H04R; H04R17/00; H04R17/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1619854A
Cited
US1802781A
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US2045404A
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US2045427A
Cited
US2145449A
Cited
US2175021A
Cited
US2305369A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-07-16 | 1955-01-15 | 1955-07-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-07-16 | 1959-01-15 | 1959-07-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-07-16 | 1963-01-15 | 1963-07-17 | $7700.00 | Window Closed / Lapsed |