Patent US2940538A successfully refreshed from Google Patents.
US2940538A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silencer
Assignee: Donaldson Co Inc
•
Filing: 1954-06-28
•
Granted: 1960-06-14
•
Expires: 1974-06-28
Abstract
No abstract record available.
Inventors
- 👤 Leino H Billey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 10:57
CPC Classifications
F; F01; F01N; F01N1/00; F01N1/003
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
FR56523E
Cited
DE452297C
Cited
FR477831A
Cited
US1487312A
Cited
US1821013A
Cited
US2184891A
Cited
US2166417A
Cited
US2189424A
Cited
US2290818A
Cited
US2326612A
Cited
US2357791A
Cited
FR994851A
Cited
US2401570A
Cited
GB610000A
Cited
US2614647A
Cited
US2705541A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-06-14 | 1963-12-14 | 1964-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-06-14 | 1967-12-14 | 1968-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-06-14 | 1971-12-14 | 1972-06-14 | $7700.00 | Window Closed / Lapsed |