Patent US3154171A successfully refreshed from Google Patents.
US3154171A
Expired / Lapsed
US
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Noise suppressing filter for microphone
Assignee: Vicon Instrument Co
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Filing: 1962-04-02
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Granted: 1964-10-27
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Expires: 1982-04-02
Abstract
No abstract record available.
Inventors
- 👤 Oliver J Knutson
- 👤 Armin E Graber
- 👤 Jr Wilbur H Wandell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:54
CPC Classifications
H; H04; H04R; H04R1/00; H04R1/08; H04R1/083; H04R1/086; H04R2410/00; H04R2410/07
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) | 1967-10-27 | 1968-04-27 | 1968-10-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-10-27 | 1972-04-27 | 1972-10-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-10-27 | 1976-04-27 | 1976-10-27 | $7700.00 | Window Closed / Lapsed |