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US3271520A
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Acoustic reflex ear protective system
Assignee: Individual
•
Filing: 1962-12-04
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Granted: 1966-09-06
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Expires: 1982-12-04
Abstract
No abstract record available.
Inventors
- 👤 John L Fletcher
- 👤 Arthur J Riopelle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:18
CPC Classifications
G; G10; G10K; G10K11/00; G10K11/16; A; A61; A61F; A61F11/00; A61F11/06; A61F11/14; A61F11/145
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2768371A
Cited
US3068319A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-09-05 | 1970-03-07 | 1970-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-09-05 | 1974-03-07 | 1974-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-09-05 | 1978-03-07 | 1978-09-06 | $7700.00 | Window Closed / Lapsed |