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US2976948A
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Mechanical device for distance discrimination of sounds
Assignee: National Research Council Canada
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Filing: 1958-01-03
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Granted: 1961-03-28
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Expires: 1978-01-03
Abstract
No abstract record available.
Inventors
- 👤 Thiessen George Jacob
- 👤 Embleton Tony Frederic Wallace
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 17:24
CPC Classifications
A; A61; A61F; A61F11/00; A61F11/06; A61F11/14
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2553539A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-03-27 | 1964-09-26 | 1965-03-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-03-27 | 1968-09-26 | 1969-03-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-03-27 | 1972-09-26 | 1973-03-28 | $7700.00 | Window Closed / Lapsed |