US3836458A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Water purification means
Assignee: Unifrax I LLC
•
Filing: 1973-04-20
•
Granted: 1974-09-17
•
Expires: 1993-04-20
Abstract
Abstract A FILTER SYSTEM IS PROVIDED FOR THE PURIFICATION OF WATER, WHEREBY PARTICULATES AND VIRUSES MAY BE ECONOMICALLY AND RELIABLY REMOVED. THE SYSTEM COMPRISES A FILTER MEANS FOR REMOVAL OF SILTS AND COLLOIDAL MATERIALS, A TREATED CARBON VIRUS FILTER, AND A SPECIALLY TREATED HONEYCOMB CARTRIDGE FOR REMOVAL OF MICROBIOLOGICAL FLOR, E.G., BBACTERIA, FUNGI, MOLDS, AND ALGE ONE MICRON OR LARGER. OPTIONALLY, THE SYSTEM MAY INCLUDE REVERSE OSMOSIS MEANS, AN ION EXCHNGE DEMINERALIZER, AND AN ULTRAFINE MEMBRANE FILTER.
Inventors
- 👤 C Wallis
- 👤 J Melnick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 07:29
CPC Classifications
B; B01; B01D; B01D61/00; B01D61/02; B01D61/025; B01D39/00; B01D39/14; B01D39/16; B01D39/18; B01D61/08; B01D61/10; C; C02; C02F; C02F1/00; C02F1/001; C02F1/004; C02F1/28; C02F1/283; C02F1/288; C02F1/50; B01D2311/00; B01D2311/04; C02F1/42; C02F1/44; C02F1/441; C02F1/444; C02F2303/00; C02F2303/04
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-09-16 | 1978-03-18 | 1978-09-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-16 | 1982-03-18 | 1982-09-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-16 | 1986-03-18 | 1986-09-17 | $7700.00 | Window Closed / Lapsed |