US3578175A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Helically wound semipermeable membrane
Assignee: Universal Water Corp
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Filing: 1969-04-23
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Granted: 1971-05-11
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Expires: 1989-04-23
Abstract
Abstract A membrane element, useful in treatment of a solution by osmosis or reverse osmosis, comprises a porous support structure around which is a semipermeable membrane preferably formed by helically winding a strip of semipermeable membrane material. The edges of adjacent turns of membrane strip are preferably overlapped and the overlapped portions are bonded together as by use of adhesive, or solvent bonding. An intermediate layer of porous backing material may be employed between the support structure and the membrane, and this can be formed by helically winding a strip, for example, of nylon cloth, preferably with contiguous edges abutted. The support structure may be of circular cross section outline, or may be of polygonal outline. A helically wound backing layer may be employed with a membrane cast on its surface.
Inventors
- 👤 Serop Manjikian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:59
CPC Classifications
B; B01; B01D; B01D63/00; B01D63/06; B01D63/062; B01D63/065; B01D69/00; B01D69/10; B01D69/107; B01D69/108
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
55 words
A membrane element comprising: a. a permeable support structure, permeable over its central surface area and having impermeable peripheral surface areas at the ends thereof, and b. a membrane comprising a semipermeable membrane strip helically wound around said support structure over said permeable central surface area with adjacent turns having contiguous edges in sealed relationship.
Claim 2
Dependent Claim
55 words
A membrane element comprising: a. a permeable support structure, permeable over its central surface area and having impermeable peripheral surface areas at the ends thereof, and b. a membrane comprising a semipermeable membrane strip helically wound around said support structure over said permeable central surface area with adjacent turns having contiguous edges in sealed relationship.
Claim 3
Dependent Claim
29 words
A membrane element according to claim 1 in which said membrane in (b) comprises a helically wound semipermeable membrane strip with overlapping edges of adjacent turns in sealed relationship.
Claim 4
Dependent Claim
25 words
A membrane element according to claim 2 in which said overlapping edges of said semipermeable membrane strip are maintained in sealed relationship by an adhesive.
Claim 5
Dependent Claim
25 words
A membrane element according to claim 2 in which said overlapping edges of said semipermeable membrane strip are maintained in sealed relationship by solvent bonding.
Claim 6
Dependent Claim
19 words
A membrane element according to claim 1 in which said support structure in (a) is of circular cross section.
Claim 7
Dependent Claim
19 words
A membrane element according to claim 1 in which said support structure in (a) is of polygonal cross section.
Claim 8
Dependent Claim
25 words
A membrane element according to claim 1 in which a permeable backing material is interposed between said support structure in (a) and said membrane (b).
Claim 9
Dependent Claim
29 words
A membrane element according to claim 7 in which a plurality of layers of backing material is interposed between said support structure in (a) and said membrane in (b).
Claim 10
Dependent Claim
20 words
A membrane element according to claim 7 in which said backing material comprises a helically wound strip of porous fabric.
Claim 11
Dependent Claim
20 words
A membrane element according to claim 7 in which said backing material comprises a helically wound strip of filter paper.
Claim 12
Dependent Claim
22 words
A membrane element according to claim 7 in which said helically wound strip of backing material has adjacent turns with abutting edges.
References Cited (Backward Citations)
US2987472A
Cited
US3042216A
Cited
US3044957A
Cited
US3156645A
Cited
US3396103A
Cited
US3446359A
Cited
US3457170A
Cited
US3442392A
Cited
US3457171A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-05-10 | 1974-11-09 | 1975-05-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-10 | 1978-11-09 | 1979-05-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-10 | 1982-11-09 | 1983-05-11 | $7700.00 | Window Closed / Lapsed |