US3722696A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spiral wound filter
Assignee: EMD Millipore Corp
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Filing: 1971-04-22
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Granted: 1973-03-27
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Expires: 1991-04-22
Abstract
Abstract A filter unit formed by spirally winding a multi-layer material around a core to form a generally cylindrical construction having two opposing spiral end surfaces. The multilayer material used to make the filter unit has at least one filter layer, at least two generally flat spacer layers formed from a material with a high void volume and at least one fluid-impermeable layer. The layers are adhered along the lengthwise and widthwise edges so that, in use, unfiltered fluid supplied to the unit through one spiral end surface must pass through a filter layer before it passes out of the unit through the opposing spiral end surface.
Inventors
- 👤 J Dwyer
- 👤 P Reiman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 07:34
CPC Classifications
B; B01; B01D; B01D25/00; B01D25/001; B01D25/22; B01D25/24
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
217 words
A filter unit construction formed from a spirally-wound multi-layer web having two opposed spiral end surfaces, said multi-layer web comprising at least one fluid-impermeable layer, at least one flat filter layer and a plurality of generally-flat spacer layers, said spacer layers being permeable to edgewise fluid flow; each surface of each filter layer contacting a spacer layer, said spacer layers being sealed so that a first set of spacer layers contacting each filter layer on a first surface is open to the atmosphere on a first spiral end surface and closed to the atmosphere on the second spiral end surface and a second set of spacer layers contacting a second surface of each filter layer is open to the atmosphere on the second spiral end surface and closed to the atmosphere on the first spiral end surface, said spacer layers and each fluid impermeable layer being arranged so that spacer layers open on opposing spiral end surfaces are not in contact, the first set of spacer layers being sealed from the atmosphere along the widthwise edge adjacent the center of the spirally-wound unit and along the widthwise edge remote from the center of the spirally-wound unit and the center of said spirally-wound unit being sealed from the atmosphere adjacent at least one spiral end spirally-wound unit surface.
Claim 2
Dependent Claim
217 words
A filter unit construction formed from a spirally-wound multi-layer web having two opposed spiral end surfaces, said multi-layer web comprising at least one fluid-impermeable layer, at least one flat filter layer and a plurality of generally-flat spacer layers, said spacer layers being permeable to edgewise fluid flow; each surface of each filter layer contacting a spacer layer, said spacer layers being sealed so that a first set of spacer layers contacting each filter layer on a first surface is open to the atmosphere on a first spiral end surface and closed to the atmosphere on the second spiral end surface and a second set of spacer layers contacting a second surface of each filter layer is open to the atmosphere on the second spiral end surface and closed to the atmosphere on the first spiral end surface, said spacer layers and each fluid impermeable layer being arranged so that spacer layers open on opposing spiral end surfaces are not in contact, the first set of spacer layers being sealed from the atmosphere along the widthwise edge adjacent the center of the spirally-wound unit and along the widthwise edge remote from the center of the spirally-wound unit and the center of said spirally-wound unit being sealed from the atmosphere adjacent at least one spiral end spirally-wound unit surface.
Claim 3
Dependent Claim
35 words
The construction of claim 1 wherein the multi-layer web is wound around a core extending across the width of the web, said core being sealed from the atmosphere adjacent at least one spiral end surface.
Claim 4
Dependent Claim
43 words
The construction of claim 1 wherein the multi-layer web comprises a filter layer, two spacer layers and a fluid-impermeable layer, said spacer layers being contiguous each to one surface of the filter layer and said fluid-impermeable layer being contiguous to one spacer layer.
Claim 5
Dependent Claim
27 words
The construction of claim 3 wherein the fluid-impermeable layer is sufficiently longer than the remaining layer so that it circumscribes the outer area surface of the construction.
Claim 6
Dependent Claim
35 words
The construction of claim 3 wherein the multi-layer web is wound around a solid core extending the width of the web, said core being sealed from the atmosphere adjacent at least one spiral end surface.
Claim 7
Dependent Claim
35 words
The filter construction of claim 1 wherein the filter layer is a laminate comprising a microporous filter material at least one surface of which is adhered to a macroporous flexible layer with a fibrouS adhesive.
Claim 8
Dependent Claim
35 words
The filter construction of claim 3 wherein the filter layer is a laminate comprising a microporous filter material at least one surface of which is adhered to a macroporous flexible layer with a fibrous adhesive.
Claim 9
Dependent Claim
40 words
A filter construction comprising the spiral filter construction of claim 1 and a housing to enclose said filter, said housing having an inlet and an outlet and means for sealing the outside cylindrical surface of said filter from said outlet.
Claim 10
Dependent Claim
40 words
A filter construction comprising the spiral filter construction of claim 3 and a housing to enclose said filter, said housing having an inlet and an outlet and means for sealing the outside cylindrical surface of said filter from said outlet.
Claim 11
Dependent Claim
40 words
A filter construction comprising the spiral filter construction of claim 6 and a housing to enclose said filter, said housing having an inlet and an outlet and means for sealing the outside cylindrical surface of said filter from said outlet.
Claim 12
Dependent Claim
36 words
The construction of claim 1 wherein the spacer layers comprise two sets of parallel strands, one set of strands being laid on the other set of strands, adhered thereto and arranged to intersect at an angle.
Claim 13
Dependent Claim
36 words
The construction of claim 2 wherein the spacer layers comprise two sets of parallel strands, one set of strands being laid on the other set of strands, adhered thereto and arranged to intersect at an angle.
Claim 14
Dependent Claim
36 words
The construction of claim 6 wherein the spacer layers comprise two sets of parallel strands, one set of strands being laid on the other set of strands, adhered thereto and arranged to intersect at an angle.
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) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |