US2740400A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Combined respirator and face shield
Assignee: AT&T Inc
•
Filing: 1954-04-30
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Granted: 1956-04-03
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Expires: 1974-04-30
Abstract
No abstract record available.
Inventors
- 👤 William B Wines
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 07:14
CPC Classifications
A; A61; A61F; A61F9/00; A61F9/02; A61F9/029; A62; A62B; A62B18/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-04-03 | 1959-10-03 | 1960-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-04-03 | 1963-10-03 | 1964-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-04-03 | 1967-10-03 | 1968-04-03 | $7700.00 | Window Closed / Lapsed |