Spirally Formed Patents (Class 210/493.4)
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Patent number: 7329326Abstract: Fluted filter media includes filter material having a plurality of flutes formed therein having alternating ends of adjacent flutes closed to force fluid through filter material. A first embodiment of the filter media includes tapered flutes which have the open ends of the flutes larger in cross-section than the closed flutes, wherein the upstream open flutes converge toward the downstream end and the upstream closed end flutes diverge toward the downstream end. A second embodiment includes filter media which is asymmetric formed with dissimilar upstream and downstream flute cross-sections with larger flute openings to the upstream side of the filter. A third embodiment includes filter media with an upstream edge crushed to improve flow at the upstream edge. A fourth embodiment includes filter media with the upstream sealing material recessed from the upstream edge for reducing effects from blockages at the upstream edge of the filter.Type: GrantFiled: February 21, 2003Date of Patent: February 12, 2008Assignee: Donaldson Company, Inc.Inventors: Wayne M. Wagner, Gary R. Gillingham, Joseph C. Tokar, Daniel T. Risch, Jim C. Rothman, Fred H. Wahlquist, Bernard A. Matthys, Gregory L. Reichter, Stephen W. Sabelko, Bryan D. Patten
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Patent number: 7323105Abstract: A direct flow filter includes a pleated filter element filtering fluid flowing axially therethrough parallel to the wall segment pleat tip bend lines. Embossments on the wall segments have a height extending along a lateral direction into a respective flow channel to maintain channel width and guiding and directing fluid axially into and along the flow channels from the upstream ends of the wall segments.Type: GrantFiled: August 11, 2004Date of Patent: January 29, 2008Assignee: Fleetguard, Inc.Inventors: Eric A. Janikowski, Jason E. Dorgan, Christopher E. Holm, Z. Gerald Liu
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Patent number: 7311831Abstract: A filtration membrane and method of making the same wherein the filtration membrane comprises obstructions and/or spacers.Type: GrantFiled: March 5, 2003Date of Patent: December 25, 2007Assignee: MIOX CorporationInventors: Wesley L. Bradford, Rodney E. Herrington, Allen D. Clement
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Patent number: 7264725Abstract: The instant invention is a hollow fiber membrane contactor, and method of making same. The hollow fiber membrane contactor includes (1) a shell, said shell having a internal bonding surface, an interlocking geometry ring being provided on said internal bonding surface; (2) a unitized structure; (3) a potting material joining said unitized structure to said shell at said interlocking geometry ring thereby forming an interlocking seal therebetween; and (4) end caps, said end caps being adjoined to lateral ends of said shell. The method of making a hollow fiber membrane contactor includes (1) providing a shell, said shell having a internal bonding surface; (2) providing an interlocking geometry ring on said internal bonding surface; (3) forming a unitized structure; (4) placing the unitized structure into said shell (5) potting said unitized structure to said shell at said interlocking geometry ring thereby forming an interlocking seal therebetween; and (6) adjoining end caps to lateral ends of said shell.Type: GrantFiled: March 4, 2004Date of Patent: September 4, 2007Assignee: Celgard Inc.Inventors: Tony R. Vido, William K. Jackson
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Patent number: 7125490Abstract: A filter has a longitudinal axis with an inner diameter defined by a hollow longitudinally extending center. The filter has fingers extend radially outwardly arcuately from the longitudinal axis. The fingers have base ends near the longitudinal axis and outer edges at extremities spaced from the longitudinal axis. The outer diameter of the filter is defined by the outer edges of the fingers. The filter is formed from a sintered porous molded thermoplastic or another material resulting in a filter more rigid than standard filters. The fingers are spaced apart from one another a predetermined, substantially fixed distance to form slots therebetween sized to capture contaminants therein.Type: GrantFiled: May 29, 2003Date of Patent: October 24, 2006Assignee: Porex CorporationInventors: Michael Andrew Clendenning, Thomas Henry Ramsey, Tripp Augustus Avett, Timothy Allen Martin
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Patent number: 7063789Abstract: A coupler for a spiral membrane filtration element having a spiral membrane enclosed within a rigid outerwrap includes a center support, a plurality of spokes extending outwardly from the center support, a circular rim coupled with the spokes, with the face of the rim being perpendicular to the axis of the overwrap. The rim includes a channel on its face for receiving a compressible seal, and a plurality of receptacles around its outer surface for joining two face-to-face adjacent couplers when a pair of aligned keepers is place in each receptacle. Exemplary embodiments of the coupler and filtration elements and filtration assemblies are provided, as well as an associated method.Type: GrantFiled: January 9, 2004Date of Patent: June 20, 2006Assignee: Koch Membrane Systems, Inc.Inventors: David M. Colby, Frederick K. Lesan, Alan M. Franks, Chang-Li Hsieh, Anjan Kumar Mukherjee
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Patent number: 7048855Abstract: Cross flow filtration cartridges are made using semipermeable membrane of sheet formation that was cast upon an integral polymeric fibrous support material which exhibits excellent permeate flow in the plane thereof and serves as both backing material and permeate carrier. A fibrous support having a thickness between about 0.4 mm and about 2 mm and at least one surface region with a mean pore size no greater than about 300 microns has a semipermeable membrane cast in situ thereupon from a liquid solution. After gelling to form a polymeric semipermeable membrane, the product is spirally wound about a porous tube in association with feed-passageway-providing sheet material, but in the absence of any separate permeate carrier, to form an effective cross-flow filtration cartridge wherein the feed flow may be spiral and the permeate discharge through one of the side edges.Type: GrantFiled: December 21, 2001Date of Patent: May 23, 2006Assignee: GE Osmonics, Inc.Inventor: Deborah de la Cruz
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Patent number: 7033497Abstract: A filter cartridge formed by winding, in a twill construction, a band-shaped unwoven cloth, which contains thermoplastic fibers and at least a part of its fiber intersections are stuck thereon, so that a cylindrical shape can be obtained, wherein 1. two types of filtrating layers are used, 2. unwoven cloth having opening hole parts is used, 3. an end face seal part is provided on both end parts of the cartridge, 4. unwoven cloth having a tongue piece part is used, or 5. two or more pieced of unwoven cloth are wound simultaneously, whereby those characteristic of the filter cartridge such as liquid permeability, filterable life, and stability of filtration accuracy can be kept in balance with each other.Type: GrantFiled: March 30, 2000Date of Patent: April 25, 2006Assignee: Chisso CorporationInventors: Osamu Yamaguchi, Shigenori Fukuda, Hideo Nobuhara
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Patent number: 7014050Abstract: A filter cartridge comprising a strip, long fiber non-woven fabric which comprises a thermoplastic fiber and in which at least a part of fiber intersections is adhered, which is wound around a perforated cylinder in a twill form, has made it possible to obtain a cylindrical filter cartridge which is excellent in a liquid-passing property, a filter life and a stability in a filtering accuracy. The thermoplastic fiber constituting the above long fiber non-woven fabric is particularly preferably a thermally adhesive composite fiber comprising a low melting point resin and a high melting point resin and having a melting point difference of 10° C. or more between those of both resins.Type: GrantFiled: November 19, 1999Date of Patent: March 21, 2006Assignee: Chisso CorporationInventors: Satoshi Ogata, Youzou Higuchi, Osamu Yamaguchi
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Patent number: 6989097Abstract: The invention disclosed relates to feed spacers used in various filtration membrane modules, such as in spiral wound membranes, used in cross-flow filtration. Such spacers have an influence in promoting the mixing between the bulk of the fluid and the fluid element adjacent to the membrane surface so as to keep the membrane surface relatively clean. To optimize these properties, novel spacer designs are disclosed having a plurality of rows of elongated strands, the strands in each row being arranged substantially in parallel to one another, with adjacent rows being attached and disposed at an angle to one another, the strands of at least one row when viewed in cross-section having a central portion of a width smaller than the width of its extremities. Novel membrane modules incorporating such feed spacers are also disclosed.Type: GrantFiled: May 16, 2003Date of Patent: January 24, 2006Assignee: National Research Council of CanadaInventors: Sandeep K. Karode, Ashwani Kumar
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Patent number: 6887343Abstract: A coating system (66, 68), winding system (158), finishing system (274, 276) and manufacturing system (FIGS. 6, 7, 22-29) is provided for spiral-wound fluted filter media (74, 130).Type: GrantFiled: December 20, 2002Date of Patent: May 3, 2005Assignee: Fleetguard, Inc.Inventors: Murray R. Schukar, Brian K. Fillbach, Gary J. Frank, Craig A. Clayton, Douglas P. Marquis, Matthew P. Henrichsen, Robert K. Miller, William C. Haberkamp, Darryl J. Gust, Kurt M. A. Badeau, Steven D. Stokstad, Travis E. Goodlund, Thomas A. Fosdal, O. Michael Bowling, Randolph G. Zoran
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Patent number: 6858141Abstract: The present Application relates to a process for the preparation of ultrafiltration membranes from polyacrylonitrile using malic acid as additives, with said membrane of molecular weight ranging between 80 to 180K, showing high purification and water permeating ability.Type: GrantFiled: August 30, 2002Date of Patent: February 22, 2005Assignee: Council of Scientific & Industrial Research (CSIR)Inventors: Sudhir Sharadchandra Kulkarni, Madhuri Himmatrao Shinde, Deepak Anandrao Musale
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Publication number: 20040238440Abstract: A filter has a longitudinal axis with an inner diameter defined by a hollow longitudinally extending center. The filter has fingers extend radially outwardly arcuately from the longitudinal axis. The fingers have base ends near the longitudinal axis and outer edges at extremities spaced from the longitudinal axis. The outer diameter of the filter is defined by the outer edges of the fingers. The filter is formed from a sintered porous molded thermoplastic or another material resulting in a filter more rigid than standard filters. The fingers are spaced apart from one another a predetermined, substantially fixed distance to form slots therebetween sized to capture contaminants therein.Type: ApplicationFiled: May 29, 2003Publication date: December 2, 2004Inventors: Michael Andrew Clendenning, Thomas Henry Ramsey, Tripp Augustus Avett, Timothy Allen Martin
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Patent number: 6797167Abstract: A composite filter medium for removing at least 99.95 percent of particulates of a size in the 3 to 4 micron range and dissolved chemical contaminants from a fluid and filters of various configurations employing the composite filter medium are disclosed. The composite filter medium comprises an adsorbent layer containing an adsorbent agent and a hydrophilic particulate intercepting layer disposed adjacent to the adsorbent layer. The composite medium has a mean flow pore diameter of about 1 to 10 microns, a bubble point of about 3 to 15 microns and an air permeability of about 0.5 to 7 liters per minute/cm2 with a pressure drop of about 0.1 bar.Type: GrantFiled: November 8, 2002Date of Patent: September 28, 2004Assignee: Koslow Technologies Corp.Inventor: Evan E. Koslow
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Publication number: 20040118771Abstract: A coating system (66, 68), winding system (158), finishing system (274, 276) and manufacturing system (FIGS. 6,7, 22-29) is provided for spiral-wound fluted filter media (74, 130).Type: ApplicationFiled: December 20, 2002Publication date: June 24, 2004Inventors: Murray R. Schukar, Brian K. Fillbach, Gary J. Frank, Craig A. Clayton, Douglas P. Marquis, Matthew P. Henrichsen, Robert K. Miller, William C. Haberkamp, Darryl J. Gust, Kurt M. A. Badeau, Steven D. Stokstad, Travis E. Goodlund, Thomas A. Fosdal, O. Michael Bowling, Randolph G. Zoran
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Publication number: 20040060861Abstract: A filter element for end face inlet formed of triangular channels which are alternately closed such that the fluid to be filtered must pass through the filter material in order to flow from the inlet side (22) to the discharge side (23). The channels are formed by alternating flat layers (17) and folded layers (18), whereby all sides of the inlet channels face a discharge channel. A particularly high filter efficiency is thereby achieved such that a large filter surface area and a high filter capacity are attained with a relatively small structural volume. The filter can be used, for example, as an air filter for various air filtration applications.Type: ApplicationFiled: June 20, 2003Publication date: April 1, 2004Applicant: Mann & Hummel GmbHInventors: Manfred Winter, Guenter Goerg, Ralf Poh
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Publication number: 20040011723Abstract: A filtration membrane and method of making the same wherein the filtration membrane comprises obstructions and/or spacers.Type: ApplicationFiled: March 5, 2003Publication date: January 22, 2004Inventors: Wesley L. Bradford, Rodney E. Herrington, Allen D. Clement
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Patent number: 6673242Abstract: There is disclosed a spiral-wound membrane module design for various membrane filtration techniques having significantly reduced fluid flow resistance in the feed stream path. Specifically, the inventive spiral-wound membrane module is designed having a corrugated entrance and exit spacers together over less than 10% of the length of the spiral wound module and a stiffener sheet wound to provide for uniform feed channel gap width.Type: GrantFiled: October 15, 2000Date of Patent: January 6, 2004Assignee: Osmotek, Inc.Inventor: Jack Herron
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Patent number: 6656362Abstract: A spiral reverse osmosis membrane element of the present invention includes a plurality of bag-shaped reverse osmosis membranes, permeated liquid passage members arranged inside the reverse osmosis membranes, and a plurality of feed liquid passage members interposed between the reverse osmosis membranes, those membranes and passage members being wound around an outer surface of a hollow pipe in a manner that only the interiors of the reverse osmosis membranes communicate with through-holes formed in the surface of the hollow pipe. Each of the feed liquid passage members is a mesh member having series of quadrilateral meshes formed by a plurality of linear members crossing each other. Two opposite cross-points out of four cross-points of each of the quadrilateral meshes are in line in parallel with an axial direction of the hollow pipe. And relations 2 mm≦X≦5 mm and X≦Y≦1.Type: GrantFiled: February 18, 2000Date of Patent: December 2, 2003Assignee: Toray Industries, Inc.Inventors: Masahiro Kihara, Shinichi Minegishi, Takayuki Nakanishi
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Patent number: 6632357Abstract: A permeable membrane system (10) for the separation of fluid components includes a laminated composition (12) having two sheets (14 and 16) formed from a polymer and positioned adjacent one another to form a fluid passage (18) therebetween. The outside surfaces (20 and 22) of the sheets (14 and 16) are permeable to allow fluid flow from the outside surface (20 and 22) to the fluid passage (18). The outside surface (20 and 22) of the laminated composition (12) includes a plurality of embossed islands spaced from one another to define feed pathways (26) around and between the embossed islands.Type: GrantFiled: November 8, 2000Date of Patent: October 14, 2003Assignee: University of South FloridaInventors: Marilyn Barger, Drew Hoff, Robert P. Carnahan, Richard A. Gilbert
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Patent number: 6598749Abstract: A filter is disclosed that includes a cylindrical filter element having a longitudinal axis, an outer periphery, an inner periphery, and a plurality of longitudinal pleats arranged in a spiral configuration in close proximity to one another. Each of the pleats has a pair of legs, and the legs of each pleat are joined to one another at a root. The roots of adjacent pleats are radially spaced from one another about the inner periphery of the filter element.Type: GrantFiled: September 12, 2001Date of Patent: July 29, 2003Assignee: CUNO IncorporatedInventors: C. Thomas Paul, Scott D. Wofsy
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Patent number: 6565747Abstract: A spiral wound type separation membrane element includes a spiral wound type membrane component formed by superposing separation membranes of membrane materials supported on nonwoven fabric members on both surfaces of a permeated liquid passage forming member and bonding three sides with an adhesive thereby defining an envelope-like membrane, mounting an opening of the envelope-like membrane on a water collection pipe and bonding the same with an adhesive and spirally winding the envelope-like membrane around the outer peripheral surface of the water collection pipe along with a raw liquid passage forming member. The outer peripheral surface of the envelope-like membrane forming the spiral wound type membrane component is covered with a sheath member, and anti-telescopic members are mounted on both end surfaces of the envelope-like membrane respectively. Each of the aforementioned components forming the spiral wound type separation membrane element is made of heat-resistant alkali-resistant plastic.Type: GrantFiled: April 11, 2000Date of Patent: May 20, 2003Assignee: Nitto Denko CorporationInventors: Takuji Shintani, Hisao Hachisuka, Katsumi Ishii
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Patent number: 6454942Abstract: A liquid separation membrane module includes a semipermeable membrane receiving a pressure of a feed liquid, and a channel material arranged so as to support the back side of the semipermeable membrane. The channel material is a tricot knitted fabric knitted by a tricot knitting machine with two reeds and has a ground stitch portion and a convex portion. The tricot knitted fabric includes a thermoplastic synthetic filament yarn with a core/sheath type conjugated fiber having a high melting point polymer as a core component and a low melting point polymer as a sheath component. Thermoplastic synthetic filament yarns for forming the ground stitch portion and the convex portion have a substantially same fineness, and the yarns in the tricot knitted fabric are bonded with one another by melt adhesion of the low melting point component to rigidity the entire knitted fabric.Type: GrantFiled: January 18, 2000Date of Patent: September 24, 2002Assignee: Nitto Denko CorporationInventors: Takuji Shintani, Hiroki Ito, Masahiko Hirose, Masaaki Ando
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Publication number: 20020117439Abstract: A filter cartridge is provided having a filter element including media preferably constructed from continuous, reinforced, geometrically symmetrical, microporous membranes having three distinct pore zones. Preferred filter elements are assembled with high and/or increased filtration area to yield increased throughput cartridge elements. Preferred filter elements are constructed from reinforced microporous membranes that include a scrim having two sides at least substantially encapsulated within a first dope and at least one additional dope coated onto each side of the encapsulated scrim prior to the first dope being quenched.Type: ApplicationFiled: September 13, 2001Publication date: August 29, 2002Inventors: C. Thomas Paul, Jeffrey A. Lucas
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Patent number: 6413424Abstract: A new sanitary filter element is described which provides a structure which cannot harbor contaminants and is readily and thoroughly cleaned as needed. The new device utilizes a uniquely configured adhesive component and membrane and tricot channel sheets which are significantly trimmed in size following adhesive curing. Such configuration eliminates structures within the filter where bacterial and other contamination, or materials which support such contaminants, can accumulate. In addition, a novel cage structure provides turbulent fluid flow while having improved strength and furnishes a site for permanent identification indicia. Finally, an improved step in the manufacturing process, in which a temporary separation sheet is positioned between the membrane and the feed spacer, prevents the occurrence of random unwanted contact adhesions between the two before and during the curing of the adhesive bonding membranes and their adjacent tricot channeling sheets.Type: GrantFiled: May 9, 2000Date of Patent: July 2, 2002Assignee: HydranauticsInventor: Irving Shelby
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Publication number: 20020070158Abstract: The invention relates to novel membrane elements, a process for their production and their use as filters, for example for ultrafiltration, nanofiltration, reverse osmosis, gas separation or pervaporation. The invention relates in particular to a membrane element comprising a core 9 and a sheath which encapsulates the core, where the sheath is formed from polymer films 10 which overlap one another at least to some extent and have been fused to one another in the overlap area.Type: ApplicationFiled: June 10, 1999Publication date: June 13, 2002Inventors: KLAUS BUECHER, ULRICH MEYER-BLUMENROTH, KLAUS NOLL, TODD REUS
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Patent number: 6375842Abstract: A desalination plant is disclosed which includes a pump for pumping water at a pressure of between 50 and 65 Bar to a generally cylindrical filter element which includes a plurality of reverse osmosis membranes defining salt passages. Immediately upstream of the filter element there is a disc with a plurality of holes in it. The disc forms an obstruction which causes a pressure drop between the upstream side thereof and the downstream side. It also divides the water flow into a series of separate streams which impinge on the end of the filter element and flow into the salt passages. The water downstream of the obstruction is not only at a lower pressure than the water upstream of the obstruction but also is flowing turbulently. The disc and filter element are in a cylindrical casing. The brine which emerges from the filter element, and which is still at a substantial pressure, can be fed through a device such as a Pelton wheel to recover some of the residual energy therefrom.Type: GrantFiled: May 31, 2000Date of Patent: April 23, 2002Assignee: Garfield International Investments LimitedInventor: William Graham
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Publication number: 20020027111Abstract: A spiral wound membrane module comprises a spiral wound membrane element including a separation membrane having high back pressure strength. In filtration running, raw water introduced from a raw water inlet of a pressure vessel is subjected to dead end filtration, and permeate is taken out from a permeate outlet. In washing, wash water containing a chemical having a contaminant separating function is introduced from an end of a water collection pipe through the permeate outlet for performing back wash reverse filtration with a back pressure of 0.05 to 0.3 MPa. The filtration running is temporarily stopped for maintaining the pressure vessel in a state sealed with the raw water and the permeate for a prescribed time. Thus, contaminants adhering to the membrane surface of the spiral wound membrane element are separated. A treatment system is formed by connecting units comprising spiral wound membrane modules in parallel with each other.Type: ApplicationFiled: July 18, 2001Publication date: March 7, 2002Applicant: Nitto Denko CorporationInventors: Masaaki Ando, Satoru Ishihara, Katsumi Ishii
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Patent number: 6352641Abstract: An improvement to a spiral wound filtration membrane is the provision of a fluid-permeable protective sheath around the inner spacer of the membrane pocket.Type: GrantFiled: June 12, 2000Date of Patent: March 5, 2002Assignee: Sartorius AGInventor: Hans-Weddo Schmidt
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Publication number: 20020020663Abstract: A filter assembly and a method of filtering a fluid using the filter assembly are disclosed. The filter assembly includes wave coils arranged axially to define a filter element. The filter element includes bottom and top ends and an inner cavity. The filter assembly also includes a base plate that engages one, or both, ends to support the wave coils. The fluid flows toward the base plate, and the base plate diverts the fluid inside or outside the inner cavity. The wave coils include crests and troughs engaging one another on adjacent wave coils to define filtration apertures. The diverted fluid is filtered through the filtration apertures such that a filtrate of the fluid passes through the inside or outside of the inner cavity, and a retentate of the fluid is retained on the other of the inside or outside of the inner cavity relative to the filtrate.Type: ApplicationFiled: August 16, 2001Publication date: February 21, 2002Inventor: E. Bayne Carew
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Patent number: 6277282Abstract: A reverse osmosis membrane element is provided that can treat a raw liquid throughout a wide raw liquid pressure range from a low pressure to a high pressure, comprising a reverse osmosis membrane, a permeated liquid passage conduit provided on one surface of the reverse osmosis membrane, and arranged to face it, and a water permeable fabric provided between the reverse osmosis membrane and the permeated liquid passage conduit; it is preferable that the water permeable fabric has an average surface roughness of 2-2 &mgr;m, that is has a pure water permeation coefficient of 0.5-5.0 m3/(m2.MPa.min) and that it is a nonwoven fabric.Type: GrantFiled: May 28, 1998Date of Patent: August 21, 2001Assignee: Toray Industries, Inc.Inventors: Masahiro Kihara, Hiroyuki Yamamura, Kazuhiko Nishimura
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Patent number: 6238561Abstract: A corrugated axial filter (148) has a plurality of flow channels (178, 180, 182, 184, 208, 212) extending axially from the upstream dirty frontside (146) of the filter to the downstream clean backside (160) of the filter. Each channel has an upstream opening (186) at the upstream dirty frontside and has top and bottom walls (188 and 190) and right and left sidewalls (192 and 194) extending from the opening rearwardly toward the downstream clean backside. The right and left sidewalls taper towards each other as they extend rearwardly to define a triangular shaped flow channel. Right and left sidewalls of adjacent flow channels are a single continuous sheet of filter material (130) in a zig-zag pattern (134) with a plurality of fold lines including a first set of fold lines (136, 138, 140, 142, 144) at the upstream dirty frontside and a second set of fold lines (150, 152, 154, 156, 158) at the downstream clean backside.Type: GrantFiled: September 24, 1999Date of Patent: May 29, 2001Assignee: Nelson Industries, Inc.Inventors: Zhili G. Liu, Tadeusz Jaroszczyk, Jerald J. Moy
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Patent number: 6235195Abstract: A filter arrangement includes a filter element configured for straight through flow and a handle member secured to the filter element. The filter element may typically have a plurality of flutes where selected ones of the flutes are open at upstream portions and closed at downstream portions, and where selected ones of the flutes are closed at the upstream portions and open at the downstream portions. In one embodiment, the handle member is secured to the central core member. In some embodiments, the handle member and the central core member are a single molded construction. The handle member can include a single aperture, such as an elongated slot, or a plurality of apertures. A method for servicing a system having a straight through flow filter element includes grasping a handle secured to the filter element, and pulling the handle to remove the filter element from the system.Type: GrantFiled: February 26, 1999Date of Patent: May 22, 2001Assignee: Donaldson Company, Inc.Inventor: Joseph C. Tokar
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Patent number: 6224767Abstract: A fluid separation element assembly comprises a fluid separation element having a membrane unit and a wrapping material formed around the membrane unit, an anti-telescoping plate attached to at least one end of the fluid separation element at a condition free to be detached, and a feed water seal member for preventing feed water from leaking through a gap between the fluid separation element and the anti-telescoping plate. The membrane unit is formed by a separation membrane, a permeate carrier material and a feed carrier material which are spirally wound around a permeate collection tube. By providing the anti-telescoping plate detachably, when the separation membrane has reached its life, it is possible to reuse other members.Type: GrantFiled: March 9, 1999Date of Patent: May 1, 2001Assignee: Toray Industries Inc.Inventors: Koji Fujiwara, Hiroyuki Ikada, Hisaaki Fujino