US3474598A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air purifier and humidifier
Assignee: Individual
•
Filing: 1968-02-27
•
Granted: 1969-10-28
•
Expires: 1988-02-27
Abstract
No abstract record available.
Inventors
- 👤 Henry P C Keuls
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:43
CPC Classifications
F; F24; F24F; F24F3/00; F24F3/12; Y; Y10; Y10S; Y10S261/00; Y10S261/15; Y10S55/00; Y10S55/35
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US152744A
Cited
US526653A
Cited
US588944A
Cited
US1097665A
Cited
AT41944B
Cited
US1241524A
Cited
US1391468A
Cited
US1394859A
Cited
US1431909A
Cited
US1586604A
Cited
US1573610A
Cited
US1650569A
Cited
US1668042A
Cited
US1690740A
Cited
US1886028A
Cited
US1960673A
Cited
US2016431A
Cited
US2225104A
Cited
US2639004A
Cited
US3212492A
Cited
US3309021A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-10-27 | 1973-04-28 | 1973-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-10-27 | 1977-04-28 | 1977-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-10-27 | 1981-04-28 | 1981-10-28 | $7700.00 | Window Closed / Lapsed |