US3675780A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filter device
Assignee: Individual
•
Filing: 1970-09-25
•
Granted: 1972-07-11
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Expires: 1990-09-25
Abstract
Abstract A compact device for filtering microorganisms such as bacteria from water or other liquid containing the same has a generally flat, envelope-type structure wherein the envelope is divided into a liquid-receiving upper chamber and a lower filtratereceiving chamber by a flexible microporous membrane.
Inventors
- 👤 Robert A Marshall
- 👤 Howard J Barach
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 05:49
CPC Classifications
B; B01; B01D; B01D35/00
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
287 words
A normally flat, flexible, easily compacted liquid filtering device comprising an envelope defined by front and back wall portions of flexible, liquid-impermeable polymeric sheet material in generally superposed relationship; a flexible filter element comprising a flexible microporous sheet of thermoplastic polymeric material to which is bonded a supporting screen of synthetic resinous material, said filter element having a pore size in the range of 0.2 to 0.45 micron and being disposed between said front and back wall portions and being further disposed in a plane parallel to the plane of said wall portions, said filter element having upper, lower and side edges; a pair of hollow frames of flexible, liquid-impermeable polymeric sheet material each coextensive with said microporous sheet, one of said frames being disposed between said microporous sheet and said front wall, the other of said frames being disposed between said microporous sheet and said back wall, said upper edge of said filter element forming a liquid-impermeable joint with an upper edge of one of said frames and with one of said wall portions, said lower edge of said filter forming a liquidimpermeable joint with the lower edge of the other of said frames and with the other of said wall portions, and each of said side portions of said filter forming a liquid-impermeable joint with the side portion of said frames and with both of said wall portions whereby and upper and a lower compartment is formed within said envelope separated by said flexible filter element, said filter element providing the sole means for liquid passing between said compartments, said upper compartment having inlet means whereby said upper compartment receives liquid to be filtered and said lower compartment having outlet means to discharge filtered liquid.
Claim 2
Dependent Claim
287 words
A normally flat, flexible, easily compacted liquid filtering device comprising an envelope defined by front and back wall portions of flexible, liquid-impermeable polymeric sheet material in generally superposed relationship; a flexible filter element comprising a flexible microporous sheet of thermoplastic polymeric material to which is bonded a supporting screen of synthetic resinous material, said filter element having a pore size in the range of 0.2 to 0.45 micron and being disposed between said front and back wall portions and being further disposed in a plane parallel to the plane of said wall portions, said filter element having upper, lower and side edges; a pair of hollow frames of flexible, liquid-impermeable polymeric sheet material each coextensive with said microporous sheet, one of said frames being disposed between said microporous sheet and said front wall, the other of said frames being disposed between said microporous sheet and said back wall, said upper edge of said filter element forming a liquid-impermeable joint with an upper edge of one of said frames and with one of said wall portions, said lower edge of said filter forming a liquidimpermeable joint with the lower edge of the other of said frames and with the other of said wall portions, and each of said side portions of said filter forming a liquid-impermeable joint with the side portion of said frames and with both of said wall portions whereby and upper and a lower compartment is formed within said envelope separated by said flexible filter element, said filter element providing the sole means for liquid passing between said compartments, said upper compartment having inlet means whereby said upper compartment receives liquid to be filtered and said lower compartment having outlet means to discharge filtered liquid.
Claim 3
Dependent Claim
33 words
The filtering device of claim 1 wherein said wall portions frames and said filter element are of heat-sealable polymeric sheet material and said liquid-impermeable joints are formed by heat sealing said sheet material.
Claim 4
Dependent Claim
19 words
The device of claim 1 wherein said polymeric material is an acrylic polymer and said resinous material is nylon.
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) | 1975-07-11 | 1976-01-10 | 1976-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-11 | 1980-01-10 | 1980-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-11 | 1984-01-10 | 1984-07-11 | $7700.00 | Window Closed / Lapsed |