Patents Assigned to USF Filtration & Separations Group, Inc.
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Patent number: 6277281Abstract: Highly asymmetric polymeric membranes with large pores which yield bubble points in the range of 0.5 to 25 psid and superior flow characteristics. The membranes can be cast from both metastable dispersions and from homogenous casting formulations. The technique of synthesis involves exposure of the cast membrane to humid air to create large surface pores on the exposed side.Type: GrantFiled: May 15, 2000Date of Patent: August 21, 2001Assignee: USF Filtration and Separations Group Inc.Inventors: Jerome Ditter, Richard A. Morris, Robert Zepf
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Patent number: 6258272Abstract: The present invention relates to hydrophilic membranes containing blends of polysulfone polymers and sulfonated polymers or copolymers, where the sulfonated polymers or copolymers are sulfonated before blending with the polysulfone polymer. The invention also relates to methods of preparing the hydrophilic membranes. In one aspect of the invention, the membranes are formed by casting a mixed polymer solution comprising a sulfone polymer and a copolymer of a sulfonated polymer and a sulfone polymer and quenching the film in an aqueous bath to produce a coagulated membrane. The membranes can be ultrafiltration or microfiltration membranes, symmetric or asymmetric.Type: GrantFiled: April 9, 1999Date of Patent: July 10, 2001Assignee: USF Filtrations and Separations Group, Inc.Inventors: I-fan Wang, Richard A. Morris, Richard McDonogh
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Patent number: 6254773Abstract: A filter assembly 1 comprising an elongate housing 2 having therein a plurality of discrete filter bundle lengths 3 disposed end to end in a series configuration. Each filter bundle length 3 comprises a multitude of micro-porous polymeric hollow fibers of the kind wherein feed to be filtered is fed to the outside of the bundle of fibers and permeate is extracted from one or both permeate discharge ends 4 of the fiber lumens. The system also includes one or more longitudinally extending feed passages 6 and 7 and one or more longitudinally extending permeate return passages, each of the permeate return passages being in fluid flow communication with each of the permeate discharge ends 4 of the fiber lumens, desirably via connecting passages 9.Type: GrantFiled: March 31, 1999Date of Patent: July 3, 2001Assignee: USF Filtration and Separations Group, Inc.Inventor: Bruce G. Biltoft
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Patent number: 6248192Abstract: A process is disclosed for making an alloy comprising the steps of cladding with a tube a plurality of metal members including a first and a second metal to form a metal composite. The metal composite is drawn for reducing the diameter thereof. The tube is removed to provide a remainder. The remainder is heated to convert the remainder to alloy. A multiplicity of composites may be processed simultaneously for producing fine alloy fibers.Type: GrantFiled: May 7, 1999Date of Patent: June 19, 2001Assignee: USF Filtration and Separations Group, IncInventors: Nathaniel R. Quick, Michael Liberman, Alexander Sobolevsky
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Patent number: 6217763Abstract: Filter cartridge assemblies are provided with a generally cylindrical filter medium which defines a cylindrically shaped core space, and a pair of end caps. A threaded base member having detent projections receives at least one of the end caps, which itself is annular and has an interior cylindrical surface defining an interior space in alignment with the core space. The interior space is also provided with interrupted threads defining detent spaces. In use, therefore, the lower end cap may be threadably coupled with the threaded base member such that the detent projections are seated in respective ones of the detent, thereby minimizing the unintended threaded uncoupling therebetween. In another aspect, the filter cartridge is most preferably “coreless” and is capable of being sleeved over a permanent, reusable perforated core element. However, the core element is removably insertable within a base member to which the filter cartridge may be coupled.Type: GrantFiled: August 11, 1999Date of Patent: April 17, 2001Assignee: USF Filtration and Separation Group, Inc.Inventors: Dianna L. Lawrence, Brian M. Raab, Carolyn A. Williams, Carl H. Hohenberger
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Patent number: 6215648Abstract: An apparatus and process is disclosed for making a capacitor having the steps of covering a first capacitor plate element with a dielectric material. The process includes encasing the first capacitor plate element and the dielectric material with a second capacitor element. The second capacitor plate element is drawn for reducing the outer diameter thereof and for forming a capacitor element. A multiplicity of the capacitor elements are encased within a second capacitor plate connector. The second capacitor plate connector is drawn for reducing the outer diameter of the metallic tube and for electrically interconnecting the multiplicity of the second capacitor plate elements with the second capacitor plate connector to form a second capacitor plate. The multiplicity of the first capacitor elements are interconnected with a first capacitor plate connector to form a first capacitor plate.Type: GrantFiled: April 27, 2000Date of Patent: April 10, 2001Assignee: USF Filtration and Separations Group, Inc.Inventors: Nathaniel R. Quick, Clinton V. Kopp, Michael Liberman, Alexander Sobolevsky
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Patent number: 6202475Abstract: A method of predicting logarithmic reduction values for a membrane filtration system having a filtrate flow portion and a bypass flow portion relative to a filtrate permeable membrane with stable input gas flow comprising: determining the filtrate flow rate through the membrane under the action of an applied test pressure, determining the membrane bypass flow rate using integrity test measurements and estimating the logarithmic reduction value using the ratio of determined filtrate flow rate and determined bypass flow rate. Methods of testing the integrity of a porous membrane are also disclosed.Type: GrantFiled: August 31, 1999Date of Patent: March 20, 2001Assignee: USF Filtration and Separations Group, Inc.Inventors: Michael R. L. Selbie, Humphrey J. J. Drummond, Warren T. Johnson
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Patent number: 6200523Abstract: An apparatus and a method is disclosed for sintering a matrix of elements such as fibers or particles by infrared heating. A multiplicity of the elements are arranged into a matrix of substantially randomly oriented elements to form a web. The web is irradiated with infrared energy for a period of time sufficient to sinter bond each of the elements to adjacent elements of the matrix randomly oriented elements.Type: GrantFiled: September 30, 1999Date of Patent: March 13, 2001Assignee: USF Filtration and Separations Group, Inc.Inventors: Nathaniel R. Quick, Tao Li, Robert Malanga, Michael Liberman, Alexander Sobolevsky, James A. McGrath
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Patent number: 6193865Abstract: Electrochemical cell having a porous substrate and a first and a second electrodes separated by an ion diffusion inhibiting partition is disclosed. The ion diffusion inhibiting partition between the two electrodes is defined by compressing the substrate and/or blocking pores of the substrate so as to inhibit but not entirely block ion diffusion between the two electrodes.Type: GrantFiled: March 15, 1999Date of Patent: February 27, 2001Assignee: USF Filtration and Separations Group, Inc.Inventors: Alastair McIndoe Hodges, Oddvar Johansen, Ronald Christopher Chatelier, Ian Andrew Maxwell, Thomas William Beck
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Patent number: 6183640Abstract: The present invention relates to anionically charge-modified membranes and methods of preparing such membranes. In one major aspect of the invention, the membranes are internally hydrophilic and formed from casting a film of a mixed polymer solution that includes an anionic agent.Type: GrantFiled: April 9, 1999Date of Patent: February 6, 2001Assignee: USF Filtration and Separations Group, Inc.Inventor: I-fan Wang
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Patent number: 6180909Abstract: An apparatus and method is disclosed for sealing a filter element to a support member. An array of bonding fibers is interposed between the filter element and the support member. Infrared energy is applied for a period of time sufficient to at least partially melt the array of bonding fibers to sinter bond the filter element to the support member.Type: GrantFiled: September 30, 1999Date of Patent: January 30, 2001Assignee: USF Filtration and Separations Group, Inc.Inventors: Nathaniel R. Quick, Tao Li, Robert Malanga, Vinod K. Sikka, Craig A. Blue
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Patent number: 6179979Abstract: A method of manufacture of a thin layer electrochemical cell (FIGS. 12, 14) comprising the steps of: forming an aperture (11) extending through a sheet (1) of electrically resistive material, said aperture defining a side wall of the cell; mounting a first thin electrode layer (13) to one side of the sheet and extending over aperture (11) whereby to define a cell first end wall; mounting a second thin electrode layer (13) to the other side of the sheet and extending over aperture (11) whereby to define a second cell end wall in substantial overlying registration with the first electrode; and providing means (16) for admission of a liquid into the cell.Type: GrantFiled: March 15, 1999Date of Patent: January 30, 2001Assignee: USF Filtration & Separations Group, Inc.Inventors: Alastair McIndoe Hodges, Thomas William Beck, Oddvar Johansen, Ian Andrew Maxwell
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Patent number: 6174420Abstract: A method of manufacture of a thin layer electrochemical cell (FIGS. 12, 14) comprising the steps of: forming an aperture (11) extending through a sheet (1) of electrically resistive material, said aperture defining a side wall of the cell, mounting a first thin electrode layer (13) to one side of the sheet and extending over aperture (11) whereby to define a cell first end wall, mounting a second thin electrode layer (13) to the other side of the sheet and extending over aperture (11) whereby to define a second cell end wall in substantial overlying registration with the first electrode, and providing means (16) for admission of a liquid into the cell.Type: GrantFiled: May 18, 1999Date of Patent: January 16, 2001Assignee: USF Filtration and Separations Group, Inc.Inventors: Alastair McIndoe Hodges, Thomas William Beck, Oddvar Johansen, Ian Andrew Maxwell
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Patent number: 6159373Abstract: A method and apparatus for recovering fine solids from a liquid feed suspension is disclosed. The apparatus has an operating cycle including a concentration part of the cycle in which solids present in the feed suspension are concentrated and a backwash part of the cycle in which supply of feed suspension to the concentrator is interrupted, the concentrator comprises a shell (11), and a plurality of elastic, hollow, microporous, polymer fibers (12) being fixed at their ends within the shell (11). Pressurized feed suspension is supplied to the outside of the fibers during said concentration part of the cycle and the filtrate may be withdrawn from the fiber lumens during the operating cycle. During the backwash cycle the concentration part of the cycle is terminated by ceasing supply of feed to said exterior surface of the fibers (12). The shell (11) is then sealed and the remaining filtrate removed from the lumens.Type: GrantFiled: August 8, 1997Date of Patent: December 12, 2000Assignee: USF Filtration & Separations Group, Inc.Inventors: Thomas William Beck, Humphrey John Jardine Drummond, Matthew Brian Lee, Clint Virgil Kopp, Warren Thomas Johnson
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Patent number: 6156200Abstract: A method and apparatus for removing fouling materials from the surface of a plurality of porous membranes (9) arranged in a membrane module (4) by providing, from within the module, by means (10) other than gas passing through the pores of said membranes, gas bubbles in a uniform distribution relative to the porous membrane array such that the bubbles move past the surfaces of the membranes (9) to dislodge fouling materials therefrom. The membranes (9) are arranged in close proximity to one another and mounted to prevent excessive movement therebetween. The bubbles also produce vibration and rubbing together of the membranes to further assist removal of fouling materials.Type: GrantFiled: December 8, 1998Date of Patent: December 5, 2000Assignee: USF Filtration & Separations Group, Inc.Inventors: Fufang Zha, Clinton V. Kopp, Robert J. McMahon, Warren T. Johnson, Thomas W. Beck
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Patent number: 6146747Abstract: The present invention relates to the field synthetic polymeric membrane materials formed from casting polyvinylidene difluoride (PVDF) polymer solutions and/or dispersions. Membranes formed in accordance with the present invention are all highly porous. Both internally isotropic membranes and highly asymmetric PVDF membranes are disclosed. Membranes of the invention may be hydrophobic or hydrophilic. The membranes of the invention are useful in a variety of microfiltration and ultrathin applications.Type: GrantFiled: May 18, 1998Date of Patent: November 14, 2000Assignee: USF Filtration and Separations Group Inc.Inventors: I-Fan Wang, Jerome F. Ditter, Robert Zepf
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Patent number: 6112395Abstract: A process is disclosed for making fine metallic fibers comprising forming a continuous tube about a plurality of coated metallic wires for providing a first cladding. The first cladding is drawn for reducing the outer diameter and for diffusion welding the coating within the cladding. The tube is mechanically removed to provide a first remainder. The first remainder is drawn for reducing the diameter thereof to transform the plurality of metallic wires into a plurality of fine metallic fibers. In one example, the diffusion welded coating is removed for providing the plurality of fine metallic fibers. In another example, a plurality of the first remainders are assembled and a continuous tube is formed about a the first remainders for providing a second cladding. The second cladding is drawn for reducing the outer diameter. The tube is mechanically removed to provide a second remainder.Type: GrantFiled: November 12, 1998Date of Patent: September 5, 2000Assignee: USF Filtration and Separations Group, Inc.Inventors: Nathaniel R. Quick, Michael Liberman, Alexander Sobolevsky, Raymond R. McNeice
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Patent number: 6110309Abstract: The present invention relates to the field synthetic polymeric membrane materials formed from casting polyvinylidene difluoride (PVDF) polymer solutions and/or dispersions. Membranes formed in accordance with the present invention are all highly porous. Both internally isotropic membranes and highly asymmetric PVDF membranes are disclosed. The membranes of the invention are useful in a variety of microfiltration and ultrathin applications.Type: GrantFiled: August 20, 1998Date of Patent: August 29, 2000Assignee: USF Filtration and Separations Group, Inc.Inventors: I-Fan Wang, Jerome F. Ditter, Robert Zepf
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Patent number: 6110369Abstract: Highly asymmetric polymeric membranes with large pores which yield bubble points in the range of 0.5 to 25 psid and superior flow characteristics. The membranes can be cast from both metastable dispersions and from homogenous casting formulations. The technique of synthesis involves exposure of the cast membrane to humid air to create large surface pores on the exposed side.Type: GrantFiled: July 29, 1997Date of Patent: August 29, 2000Assignee: USF Filtration and Separations Group, Inc.Inventors: Jerome Ditter, Richard A. Morris, Robert Zepf
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Patent number: 6096207Abstract: A filter cartridge assembly includes a filter cartridge having a generally cylindrical filter medium which defines a cylindrically shaped core space, and a pair of end caps fixed to opposite ends of the filter medium. Most preferably, the filter cartridge is "coreless" in that it is not provided with an integral support core structure. At least one of the end caps (e.g., the proximal end cap) is annular and has an interior cylindrical surface defining an interior space in alignment with the core space. A truncated generally conically shaped seal skirt is operatively associated with the annular end caps. The filter cartridge is sleeved over reusable support core structure which includes a base having a truncated conically shaped seal skirt, and a tubular perforated rigid core element fixed at one end to the base. The annular end-cap and the base of the support core structure are removably mechanically coupled to one another, most preferably by being threadably interconnected.Type: GrantFiled: September 16, 1998Date of Patent: August 1, 2000Assignee: USF Filtration and Separations Group Inc.Inventors: Charles S. Hoffman, Jr., Norman F. Robillard, Robert H. Sumner