US3421290A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Indoor smoke removal system
Assignee: United Air Specialists Inc
•
Filing: 1967-02-16
•
Granted: 1969-01-14
•
Expires: 1987-02-16
Abstract
No abstract record available.
Inventors
- 👤 William A Cheney
- 👤 Durwood G Rorie Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:57
CPC Classifications
B; B08; B08B; B08B15/00; B08B15/002
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US3123988A
Cited
US1138470A
Cited
US1508367A
Cited
US1502844A
Cited
US2084408A
Cited
US2210458A
Cited
US2181851A
Cited
US2255677A
Cited
US2318093A
Cited
US2363839A
Cited
US2565933A
Cited
US3011230A
Cited
US3028715A
Cited
US3173980A
Cited
US3233391A
Cited
US3257778A
Cited
US3271932A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-01-14 | 1972-07-15 | 1973-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-01-14 | 1976-07-15 | 1977-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-01-14 | 1980-07-15 | 1981-01-14 | $7700.00 | Window Closed / Lapsed |