US2844820A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Noise protective device
Assignee: MSA Safety Inc
•
Filing: 1955-08-29
•
Granted: 1958-07-29
•
Expires: 1975-08-29
Abstract
No abstract record available.
Inventors
- 👤 Harry W Austin
- 👤 Robert R Hornickel
- 👤 Don E Sietam
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 06:42
CPC Classifications
A; A42; A42B; A42B1/00; A42B1/018; A42B1/0186; A42B1/0188; A42B3/00; A42B3/04; A42B3/16; A42B3/166
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US970544A
Cited
US1225422A
Cited
US1456524A
Cited
US1479017A
Cited
US1774325A
Cited
US2282830A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-07-28 | 1962-01-27 | 1962-07-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-07-28 | 1966-01-27 | 1966-07-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-07-28 | 1970-01-27 | 1970-07-29 | $7700.00 | Window Closed / Lapsed |