US3429397A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Laminated conduit and acoustic silencer
Assignee: Walker Manufacturing Co
•
Filing: 1967-09-26
•
Granted: 1969-02-25
•
Expires: 1987-09-26
Abstract
No abstract record available.
Inventors
- 👤 David A Case
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:16
CPC Classifications
F; F01; F01N; F01N1/00; F01N1/003; F01N1/006; F01N1/02; F01N1/023; F01N2490/00; F01N2490/20
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USRE25909E
Cited
US2297046A
Cited
US2926743A
Cited
US3209787A
Cited
US3176790A
Cited
US3276108A
Cited
US3263772A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-02-25 | 1972-08-26 | 1973-02-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-02-25 | 1976-08-26 | 1977-02-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-02-25 | 1980-08-26 | 1981-02-25 | $7700.00 | Window Closed / Lapsed |